From 01fa7069b33cedd4992f7b0f21b29916b949de1c Mon Sep 17 00:00:00 2001 From: Cubitect Date: Sun, 7 Jan 2024 11:54:31 +0100 Subject: [PATCH] Some changes for v4.0.0 (locations finder + biome sampling + area input change) * added biome samples filter to check biome proportions (#173, #266) * added outline display for the area of selected conditions (WIP) * added "from-visible" to conditions editor (#271) * added Locations to Search tab, to look for positions in the current seed * moved Tiggers to Search tab * changed area/position input fields to use block coordinates (#265) * changed spiral iterator to use an arbitrary, user defined step size * fixed octave options and added generated display texts (#253) --- buildguide.md | 2 +- cubiomes | 2 +- cubiomes-viewer.pro | 11 +- ...thub.cubitect.cubiomes-viewer.metainfo.xml | 4 +- rc/dark.qss | 2 +- src/aboutdialog.h | 6 +- src/conditiondialog.cpp | 355 +++++++----- src/conditiondialog.h | 14 +- src/conditiondialog.ui | 261 +++++++-- src/configdialog.cpp | 4 +- src/formconditions.cpp | 10 +- src/formconditions.h | 1 + src/formsearchcontrol.cpp | 24 +- src/formsearchcontrol.h | 1 + src/formsearchcontrol.ui | 2 +- src/gotodialog.cpp | 2 +- src/layerdialog.cpp | 221 ++++--- src/layerdialog.h | 11 +- src/mainwindow.cpp | 84 ++- src/mainwindow.h | 5 +- src/mainwindow.ui | 153 ++--- src/mapview.cpp | 51 +- src/mapview.h | 4 + src/rangeslider.cpp | 2 +- src/scripts.cpp | 44 +- src/scripts.h | 5 +- src/search.cpp | 546 +++++++++++------- src/search.h | 215 ++++--- src/searchthread.cpp | 9 +- src/tabbiomes.cpp | 17 +- src/tablocations.cpp | 437 ++++++++++++++ src/tablocations.h | 78 +++ src/tablocations.ui | 175 ++++++ src/tabstructures.cpp | 17 +- src/tabtriggers.cpp | 16 +- src/tabtriggers.ui | 2 +- src/util.cpp | 30 +- src/util.h | 6 + src/world.cpp | 26 +- src/world.h | 11 + 40 files changed, 1981 insertions(+), 885 deletions(-) create mode 100644 src/tablocations.cpp create mode 100644 src/tablocations.h create mode 100644 src/tablocations.ui diff --git a/buildguide.md b/buildguide.md index dd1d451..9a39393 100644 --- a/buildguide.md +++ b/buildguide.md @@ -1,7 +1,7 @@ # Cubiomes Viewer Build Instructions Cubiomes Viewer is a Qt5 application and requires: -* Qt5.9 or newer (Qt6 is not supported) and a +* Qt5.9 or newer (Qt6 might work, but isn't currently supported) and a * GNU C++ compiler (GCC or Clang). The cubiomes library is included as a submodule to this repository. diff --git a/cubiomes b/cubiomes index 6b36603..c3ff21a 160000 --- a/cubiomes +++ b/cubiomes @@ -1 +1 @@ -Subproject commit 6b36603d2dc31f6ef8a3d4746c9b64ad3ace0a00 +Subproject commit c3ff21a1a8b6bf362221db3f4dee71a0dc7dba9b diff --git a/cubiomes-viewer.pro b/cubiomes-viewer.pro index c7664ce..d0e284c 100644 --- a/cubiomes-viewer.pro +++ b/cubiomes-viewer.pro @@ -32,6 +32,10 @@ win32: { static_gnu: { LIBS += -static -static-libgcc -static-libstdc++ } +sanitizer: { + QMAKE_CFLAGS += -fsanitize=undefined + LIBS += -lubsan -ldl +} gcc { greaterThan(QMAKE_GCC_MAJOR_VERSION, 9): QMAKE_CXXFLAGS += -Wno-deprecated-copy @@ -39,10 +43,6 @@ gcc { CONFIG(debug, debug|release): { CUTARGET = debug - !win32 { - QMAKE_CFLAGS += -fsanitize=undefined - LIBS += -lubsan -ldl - } } else { CUTARGET = release } @@ -115,6 +115,7 @@ SOURCES += \ src/search.cpp \ src/searchthread.cpp \ src/tabbiomes.cpp \ + src/tablocations.cpp \ src/tabstructures.cpp \ src/tabtriggers.cpp \ src/mainwindow.cpp \ @@ -182,6 +183,7 @@ HEADERS += \ src/searchthread.h \ src/seedtables.h \ src/tabbiomes.h \ + src/tablocations.h \ src/tabstructures.h \ src/tabtriggers.h \ src/mainwindow.h \ @@ -206,6 +208,7 @@ FORMS += \ src/mainwindow.ui \ src/rangedialog.ui \ src/tabbiomes.ui \ + src/tablocations.ui \ src/tabstructures.ui \ src/tabtriggers.ui diff --git a/etc/com.github.cubitect.cubiomes-viewer.metainfo.xml b/etc/com.github.cubitect.cubiomes-viewer.metainfo.xml index 6fa02b5..920fc30 100644 --- a/etc/com.github.cubitect.cubiomes-viewer.metainfo.xml +++ b/etc/com.github.cubitect.cubiomes-viewer.metainfo.xml @@ -9,11 +9,11 @@ Cubiomes Viewer An efficient Minecraft seed finder and map viewer. -

Cubiomes Viewer offers highly customizable seed-finding utilities and a map viewer for the biome and structure generation of Minecraft Java Edition for the main releases up to 1.19.

+

Cubiomes Viewer offers highly customizable seed-finding utilities and a map viewer for the biome and structure generation of Minecraft Java Edition for the main releases up to 1.21.

 - + diff --git a/rc/dark.qss b/rc/dark.qss index 9d754cb..268df81 100644 --- a/rc/dark.qss +++ b/rc/dark.qss @@ -2116,7 +2116,7 @@ https://doc.qt.io/qt-5/stylesheet-examples.html#customizing-qsplitter --------------------------------------------------------------------------- */ QSplitter { - background-color: #455364; + background-color: #19232D; /*#455364;*/ spacing: 0px; padding: 0px; margin: 0px; diff --git a/src/aboutdialog.h b/src/aboutdialog.h index c38e621..9df5e3e 100644 --- a/src/aboutdialog.h +++ b/src/aboutdialog.h @@ -4,9 +4,9 @@ #include #include -#define VERS_MAJOR 3 -#define VERS_MINOR 4 -#define VERS_PATCH 2 // negative patch number designates a development version +#define VERS_MAJOR 4 +#define VERS_MINOR 0 +#define VERS_PATCH -1 // negative patch number designates a development version // returns +1 if newer, -1 if older and 0 if equal inline int cmpVers(int major, int minor, int patch) diff --git a/src/conditiondialog.cpp b/src/conditiondialog.cpp index 8577e1f..ea2055e 100644 --- a/src/conditiondialog.cpp +++ b/src/conditiondialog.cpp @@ -21,29 +21,16 @@ #include -static QString getTip(int mc, int layer, uint32_t flags, int id) -{ - uint64_t mL = 0, mM = 0; - genPotential(&mL, &mM, layer, mc, flags, id); - QString tip = ConditionDialog::tr("Generates any of:"); - for (int j = 0; j < 64; j++) - if (mL & (1ULL << j)) - tip += QString("\n") + getBiomeDisplay(mc, j); - for (int j = 0; j < 64; j++) - if (mM & (1ULL << j)) - tip += QString("\n") + getBiomeDisplay(mc, 128+j); - return tip; -} - #define WARNING_CHAR QChar(0x26A0) -ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcversion, QListWidgetItem *item, Condition *initcond) +ConditionDialog::ConditionDialog(FormConditions *parent, MapView *mapview, Config *config, WorldInfo wi, QListWidgetItem *item, Condition *initcond) : QDialog(parent, Qt::WindowMinMaxButtonsHint | Qt::WindowCloseButtonHint) , ui(new Ui::ConditionDialog) , luahash() + , mapview(mapview) , config(config) , item(item) - , mc(mcversion) + , wi(wi) { memset(&cond, 0, sizeof(cond)); ui->setupUi(this); @@ -55,7 +42,7 @@ ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcv textDescription->setSizeAdjustPolicy(QAbstractScrollArea::AdjustToContents); ui->collapseDescription->init(tr("Description/Notes"), textDescription, true); - const char *p_mcs = mc2str(mc); + const char *p_mcs = mc2str(wi.mc); QString mcs = tr("MC %1", "Minecraft version").arg(p_mcs ? p_mcs : "?"); ui->labelMC->setText(mcs); @@ -86,20 +73,20 @@ ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcv if (c.save == initcond->save) continue; if (c.save == initcond->relative) - initindex = ui->comboBoxRelative->count(); + initindex = ui->comboRelative->count(); } QString condstr = c.summary(false).simplified(); - ui->comboBoxRelative->addItem(condstr, c.save); + ui->comboRelative->addItem(condstr, c.save); } if (initindex < 0) { if (initcond && initcond->relative > 0) { - initindex = ui->comboBoxRelative->count(); + initindex = ui->comboRelative->count(); QString condstr = QString("[%1] %2 broken reference") .arg(initcond->relative, 2, 10, QChar('0')) .arg(WARNING_CHAR); - ui->comboBoxRelative->addItem(condstr, initcond->relative); + ui->comboRelative->addItem(condstr, initcond->relative); } else { @@ -117,6 +104,8 @@ ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcv ui->lineSquare->setValidator(uintval); ui->lineRadius->setValidator(uintval); + ui->lineSpiralStep->setValidator(new QIntValidator(1, 0xffff, this)); + ui->lineBiomeSize->setValidator(new QIntValidator(1, INT_MAX, this)); ui->lineTolerance->setValidator(new QIntValidator(0, 255, this)); @@ -125,28 +114,31 @@ ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcv ui->lineMin->setValidator(new QDoubleValidator(-1e6, 1e6, 4, this)); ui->lineMax->setValidator(new QDoubleValidator(-1e6, 1e6, 4, this)); - ui->comboBoxCat->setItemDelegate(new ComboBoxDelegate(this, ui->comboBoxCat)); - ui->comboBoxType->setItemDelegate(new ComboBoxDelegate(this, ui->comboBoxType)); + ui->lineCoverage->setValidator(new QDoubleValidator(0.0001, 100.0000, 4, this)); + ui->lineConfidence->setValidator(new QDoubleValidator(0.0001, 99.9999, 4, this)); - //qobject_cast(ui->comboBoxCat->view())->setSpacing(1); - //qobject_cast(ui->comboBoxType->view())->setSpacing(1); + ui->comboCat->setItemDelegate(new ComboBoxDelegate(this, ui->comboCat)); + ui->comboType->setItemDelegate(new ComboBoxDelegate(this, ui->comboType)); - ui->comboBoxCat->addItem(tr("Select category")); - ui->comboBoxCat->insertSeparator(1); - ui->comboBoxCat->addItem(getPix("helper"), tr("Algorithm helpers"), CAT_HELPER); - ui->comboBoxCat->addItem(getPix("quad"), tr("Quad-structure"), CAT_QUAD); - ui->comboBoxCat->addItem(getPix("stronghold"), tr("Structures"), CAT_STRUCT); - ui->comboBoxCat->addItem(getPix("overworld"), tr("Biomes"), CAT_BIOMES); - ui->comboBoxCat->addItem(getPix("nether"), tr("Nether biomes"), CAT_NETHER); - ui->comboBoxCat->addItem(getPix("the_end"), tr("End biomes"), CAT_END); - ui->comboBoxCat->addItem(getPix("slime"), tr("Other"), CAT_OTHER); - int fmh = ui->comboBoxCat->fontMetrics().height() + 8; - ui->comboBoxCat->setIconSize(QSize(fmh, fmh)); - ui->comboBoxType->setIconSize(QSize(fmh, fmh)); + //qobject_cast(ui->comboCat->view())->setSpacing(1); + //qobject_cast(ui->comboType->view())->setSpacing(1); + + ui->comboCat->addItem(tr("Select category")); + ui->comboCat->insertSeparator(1); + ui->comboCat->addItem(getPix("helper"), tr("Algorithm helpers"), CAT_HELPER); + ui->comboCat->addItem(getPix("quad"), tr("Quad-structure"), CAT_QUAD); + ui->comboCat->addItem(getPix("stronghold"), tr("Structures"), CAT_STRUCT); + ui->comboCat->addItem(getPix("overworld"), tr("Biomes"), CAT_BIOMES); + ui->comboCat->addItem(getPix("nether"), tr("Nether biomes"), CAT_NETHER); + ui->comboCat->addItem(getPix("the_end"), tr("End biomes"), CAT_END); + ui->comboCat->addItem(getPix("slime"), tr("Other"), CAT_OTHER); + int fmh = ui->comboCat->fontMetrics().height() + 8; + ui->comboCat->setIconSize(QSize(fmh, fmh)); + ui->comboType->setIconSize(QSize(fmh, fmh)); for (int i = 0; i < 256; i++) { - QString bname = getBiomeDisplay(mc, i); + QString bname = getBiomeDisplay(wi.mc, i); if (bname.isEmpty()) continue; QCheckBox *cb = new QCheckBox(bname); @@ -214,7 +206,7 @@ ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcv if (i == NP_DEPTH) { LabeledRange *lr; - if (mc <= MC_1_17) + if (wi.mc <= MC_1_17) lr = new LabeledRange(this, 0, 256); else lr = new LabeledRange(this, -64, 320); @@ -253,15 +245,15 @@ ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcv std::vector ids; for (int id = 0; id < 256; id++) ids.push_back(id); - IdCmp cmp(IdCmp::SORT_LEX, mc, DIM_UNDEF); + IdCmp cmp(IdCmp::SORT_LEX, wi.mc, DIM_UNDEF); std::sort(ids.begin(), ids.end(), cmp); for (int id : ids) { - const int *lim = getBiomeParaLimits(mc, id); + const int *lim = getBiomeParaLimits(wi.mc, id); if (!lim) continue; - NoiseBiomeIndicator *cb = new NoiseBiomeIndicator(getBiomeDisplay(mc, id), this); + NoiseBiomeIndicator *cb = new NoiseBiomeIndicator(getBiomeDisplay(wi.mc, id), this); QString tip = "
";
         for (int j = 0; j < NP_MAX; j++)
         {
@@ -310,6 +302,8 @@ ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcv
     ui->checkSkipRef->setChecked(false);
     ui->radioSquare->setChecked(true);
     ui->checkRadius->setChecked(false);
+    ui->lineCoverage->setText("100");
+    ui->lineConfidence->setText("95");
     onCheckStartChanged(false);
     on_comboClimatePara_currentIndexChanged(0);
 
@@ -328,22 +322,25 @@ ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcv
             ui->comboLua->setCurrentIndex(-1); // force index change
         ui->comboLua->setCurrentIndex(ui->comboLua->findData(QVariant::fromValue(cond.hash)));
 
-        ui->comboBoxCat->setCurrentIndex(ui->comboBoxCat->findData(ft.cat));
-        for (int i = 0; i < ui->comboBoxType->count(); i++)
+        ui->comboCat->setCurrentIndex(ui->comboCat->findData(ft.cat));
+        for (int i = 0; i < ui->comboType->count(); i++)
         {
-            int type = ui->comboBoxType->itemData(i, Qt::UserRole).toInt();
+            int type = ui->comboType->itemData(i, Qt::UserRole).toInt();
             if (type == cond.type)
             {
-                ui->comboBoxType->setCurrentIndex(i);
+                ui->comboType->setCurrentIndex(i);
                 break;
             }
         }
 
-        ui->comboBoxRelative->setCurrentIndex(initindex);
-        on_comboBoxRelative_activated(initindex);
+        ui->comboRelative->setCurrentIndex(initindex);
+        on_comboRelative_activated(initindex);
         ui->textEditLua->document()->setModified(false);
 
-        ui->comboMatchBiome->insertItem(0, getBiomeDisplay(mc, cond.biomeId), QVariant::fromValue(cond.biomeId));
+        if (cond.step)
+            ui->lineSpiralStep->setText(QString::number(cond.step));
+
+        ui->comboMatchBiome->insertItem(0, getBiomeDisplay(wi.mc, cond.biomeId), QVariant::fromValue(cond.biomeId));
         ui->comboMatchBiome->setCurrentIndex(0);
 
         ui->comboClimatePara->setCurrentIndex(ui->comboClimatePara->findData(QVariant::fromValue(cond.para)));
@@ -364,6 +361,10 @@ ConditionDialog::ConditionDialog(FormConditions *parent, Config *config, int mcv
 
         ui->checkApprox->setChecked(cond.flags & Condition::FLG_APPROX);
         ui->checkMatchAny->setChecked(cond.flags & Condition::FLG_MATCH_ANY);
+        ui->lineCoverage->setText(QString::number(cond.converage ? cond.converage * 100 : 100));
+        ui->lineConfidence->setText(QString::number(cond.confidence ? cond.confidence * 100 : 95));
+        ui->checkSamplePos->setChecked(cond.count == 1);
+
         int i, n = ui->comboY->count();
         for (i = 0; i < n; i++)
             if (ui->comboY->itemText(i).section(' ', 0, 0).toInt() == cond.y)
@@ -475,26 +476,40 @@ void ConditionDialog::addTempCat(int temp, QString name)
     int r = temp % Special;
     ui->gridLayoutTemps->addWidget(tempsboxes[temp], r, c * 2 + 0);
     ui->gridLayoutTemps->addWidget(l, r, c * 2 + 1);
-    if (mc > MC_1_6 && mc <= MC_1_17)
-        l->setToolTip(getTip(mc, L_SPECIAL_1024, 0, r + (temp >= Special ? 256 : 0)));
+    if (wi.mc > MC_1_6 && wi.mc <= MC_1_17)
+    {
+        uint64_t mL = 0, mM = 0;
+        genPotential(&mL, &mM, L_SPECIAL_1024, wi.mc, 0, r + (temp >= Special ? 256 : 0));
+        QString tip = ConditionDialog::tr("Generates any of:");
+        for (int j = 0; j < 64; j++)
+            if (mL & (1ULL << j))
+                tip += QString("\n") + getBiomeDisplay(wi.mc, j);
+        for (int j = 0; j < 64; j++)
+            if (mM & (1ULL << j))
+                tip += QString("\n") + getBiomeDisplay(wi.mc, 128+j);
+        l->setToolTip(tip);
+    }
 }
 
 void ConditionDialog::updateMode()
 {
-    int filterindex = ui->comboBoxType->currentData().toInt();
+    int filterindex = ui->comboType->currentData().toInt();
     const FilterInfo &ft = g_filterinfo.list[filterindex];
 
     ui->lineSummary->setPlaceholderText(QApplication::translate("Filter", ft.name));
 
     QPalette pal;
-    if (mc < ft.mcmin || mc > ft.mcmax)
+    if (wi.mc < ft.mcmin || wi.mc > ft.mcmax)
         pal.setColor(QPalette::Normal, QPalette::Button, QColor(255,0,0,127));
-    ui->comboBoxType->setPalette(pal);
+    ui->comboType->setPalette(pal);
 
     ui->groupBoxGeneral->setEnabled(filterindex != F_SELECT);
     ui->groupBoxPosition->setEnabled(filterindex != F_SELECT);
 
-    ui->checkRadius->setEnabled(ft.rmax);
+    ui->checkRadius->setEnabled(ft.loc & FilterInfo::LOC_R);
+
+    bool p1 = ft.loc & FilterInfo::LOC_1;
+    bool p2 = ft.loc & FilterInfo::LOC_2;
 
     if (ui->checkRadius->isEnabled() && ui->checkRadius->isChecked())
     {
@@ -516,28 +531,44 @@ void ConditionDialog::updateMode()
     }
     else
     {
-        bool custom = ui->radioCustom->isChecked();
-
         ui->lineRadius->setEnabled(false);
 
-        ui->radioSquare->setEnabled(ft.area);
-        ui->radioCustom->setEnabled(ft.area);
+        ui->radioSquare->setEnabled(p2);
+        ui->radioCustom->setEnabled(p2);
 
-        ui->lineSquare->setEnabled(!custom && ft.area);
-
-        ui->labelX1->setEnabled(ft.coord && (custom || !ft.area));
-        ui->labelZ1->setEnabled(ft.coord && (custom || !ft.area));
-        ui->labelX2->setEnabled(custom && ft.area);
-        ui->labelZ2->setEnabled(custom && ft.area);
-        ui->lineEditX1->setEnabled(ft.coord && (custom || !ft.area));
-        ui->lineEditZ1->setEnabled(ft.coord && (custom || !ft.area));
-        ui->lineEditX2->setEnabled(custom && ft.area);
-        ui->lineEditZ2->setEnabled(custom && ft.area);
+        if (ui->radioCustom->isChecked())
+        {
+            ui->lineSquare->setEnabled(false);
+            ui->labelX1->setEnabled(p1);
+            ui->labelZ1->setEnabled(p1);
+            ui->labelX2->setEnabled(p2);
+            ui->labelZ2->setEnabled(p2);
+            ui->lineEditX1->setEnabled(p1);
+            ui->lineEditZ1->setEnabled(p1);
+            ui->lineEditX2->setEnabled(p2);
+            ui->lineEditZ2->setEnabled(p2);
+        }
+        else
+        {
+            ui->lineSquare->setEnabled(p2);
+            ui->labelX1->setEnabled(p1 && !p2);
+            ui->labelZ1->setEnabled(p1 && !p2);
+            ui->labelX2->setEnabled(false);
+            ui->labelZ2->setEnabled(false);
+            ui->lineEditX1->setEnabled(p1 && !p2);
+            ui->lineEditZ1->setEnabled(p1 && !p2);
+            ui->lineEditX2->setEnabled(false);
+            ui->lineEditZ2->setEnabled(false);
+        }
     }
 
-    ui->labelSpinBox->setEnabled(ft.count);
-    ui->spinBox->setEnabled(ft.count);
-    ui->checkSkipRef->setEnabled(ft.count);
+    ui->buttonFromVisible->setEnabled(mapview && p2 && ui->comboRelative->currentIndex() == 0);
+
+    bool cnt = ft.branch == FilterInfo::BR_CLUST;
+
+    ui->labelSpinBox->setEnabled(cnt);
+    ui->spinBox->setEnabled(cnt);
+    ui->checkSkipRef->setEnabled(cnt);
 
     ui->labelY->setEnabled(ft.hasy);
     ui->comboY->setEnabled(ft.hasy);
@@ -561,14 +592,18 @@ void ConditionDialog::updateMode()
     else if (ft.cat == CAT_BIOMES || ft.cat == CAT_NETHER || ft.cat == CAT_END)
     {
         ui->stackedWidget->setCurrentWidget(ui->pageBiomes);
-        ui->checkApprox->setEnabled(mc <= MC_1_17 || ft.step == 4);
+        ui->checkApprox->setEnabled(wi.mc <= MC_1_17 || ft.grid == 4);
         ui->checkMatchAny->setEnabled(true);
+        if (filterindex == F_BIOME_SAMPLE)
+            ui->stackedBiome->setCurrentWidget(ui->pageBiomeOptSample);
+        else
+            ui->stackedBiome->setCurrentWidget(ui->pageBiomeOpt);
     }
     else if (filterindex == F_VILLAGE)
     {
         ui->stackedWidget->setCurrentWidget(ui->pageVillage);
-        ui->checkStartPieces->setEnabled(mc >= MC_1_14);
-        ui->checkAbandoned->setEnabled(filterindex == F_VILLAGE && mc >= MC_1_10);
+        ui->checkStartPieces->setEnabled(wi.mc >= MC_1_14);
+        ui->checkAbandoned->setEnabled(filterindex == F_VILLAGE && wi.mc >= MC_1_10);
     }
     else if (filterindex == F_FORTRESS)
     {
@@ -578,22 +613,22 @@ void ConditionDialog::updateMode()
     else if (filterindex == F_BASTION)
     {
         ui->stackedWidget->setCurrentWidget(ui->pageBastion);
-        ui->checkStartBastion->setEnabled(mc >= MC_1_16_1);
+        ui->checkStartBastion->setEnabled(wi.mc >= MC_1_16_1);
     }
     else if (filterindex == F_PORTAL || filterindex == F_PORTALN)
     {
         ui->stackedWidget->setCurrentWidget(ui->pagePortal);
-        ui->checkStartPortal->setEnabled(mc >= MC_1_16_1);
+        ui->checkStartPortal->setEnabled(wi.mc >= MC_1_16_1);
     }
     else if (filterindex == F_ENDCITY)
     {
         ui->stackedWidget->setCurrentWidget(ui->pageEndCity);
-        ui->checkBasement->setEnabled(mc >= MC_1_9);
+        ui->checkBasement->setEnabled(wi.mc >= MC_1_9);
     }
     else if (filterindex == F_IGLOO)
     {
         ui->stackedWidget->setCurrentWidget(ui->pageIgloo);
-        ui->checkEndShip->setEnabled(mc >= MC_1_9);
+        ui->checkEndShip->setEnabled(wi.mc >= MC_1_9);
     }
     else if (filterindex == F_HEIGHT)
     {
@@ -603,6 +638,10 @@ void ConditionDialog::updateMode()
     {
         ui->stackedWidget->setCurrentWidget(ui->pageLua);
     }
+    else if (filterindex == F_SPIRAL)
+    {
+        ui->stackedWidget->setCurrentWidget(ui->pageSpiral);
+    }
     else
     {
         ui->stackedWidget->setCurrentWidget(ui->pageNone);
@@ -610,26 +649,14 @@ void ConditionDialog::updateMode()
 
     updateBiomeSelection();
 
-    QString loc = "";
-    QString areatip = "";
-    QString lowtip = "";
-    QString uptip = "";
+    QString loc = tr("Location");
+    QString areatip = tr("From floor(-x/2) to floor(x/2) on both axes (inclusive)");
+    QString lowtip = tr("Lower bound (inclusive)");
+    QString uptip = tr("Upper bound (inclusive)");
+
+    if (ft.grid > 1)
+        loc += " " + tr("(sampled on a grid of scale 1:%1)").arg(ft.grid);
 
-    if (ft.step > 1)
-    {
-        QString multxt = QString("%1%2").arg(QChar(0xD7)).arg(ft.step);
-        loc = tr("Location (coordinates are multiplied by %1)").arg(multxt);
-        areatip = tr("From floor(-x/2)%1 to floor(x/2)%1 on both axes (inclusive)").arg(multxt);
-        lowtip = tr("Lower bound %1 (inclusive)").arg(multxt);
-        uptip = tr("Upper bound %1 (inclusive)").arg(multxt);
-    }
-    else
-    {
-        loc = tr("Location");
-        areatip = tr("From floor(-x/2) to floor(x/2) on both axes (inclusive)");
-        lowtip = tr("Lower bound (inclusive)");
-        uptip = tr("Upper bound (inclusive)");
-    }
     ui->groupBoxPosition->setTitle(loc);
     ui->radioSquare->setToolTip(areatip);
     ui->labelX1->setToolTip(lowtip);
@@ -646,7 +673,7 @@ void ConditionDialog::updateMode()
 
 void ConditionDialog::updateBiomeSelection()
 {
-    int filterindex = ui->comboBoxType->currentData().toInt();
+    int filterindex = ui->comboType->currentData().toInt();
     const FilterInfo &ft = g_filterinfo.list[filterindex];
 
     // clear tool tips
@@ -669,14 +696,14 @@ void ConditionDialog::updateBiomeSelection()
         available.push_back(cold_ocean);
         available.push_back(frozen_ocean);
     }
-    else if (ft.cat == CAT_BIOMES && mc > MC_B1_7 && mc <= MC_1_17)
+    else if (ft.cat == CAT_BIOMES && wi.mc > MC_B1_7 && wi.mc <= MC_1_17)
     {
         int layerId = ft.layer;
         if (layerId == 0)
         {
             Generator tmp;
-            setupGenerator(&tmp, mc, 0);
-            const Layer *l = getLayerForScale(&tmp, ft.step);
+            setupGenerator(&tmp, wi.mc, 0);
+            const Layer *l = getLayerForScale(&tmp, ft.grid);
             if (l)
                 layerId = l - tmp.ls.layers;
         }
@@ -688,7 +715,7 @@ void ConditionDialog::updateBiomeSelection()
             QCheckBox *cb = it.second;
             uint64_t mL = 0, mM = 0;
             uint32_t flags = 0;
-            genPotential(&mL, &mM, layerId, mc, flags, it.first);
+            genPotential(&mL, &mM, layerId, wi.mc, flags, it.first);
 
             if (mL || mM)
             {
@@ -699,12 +726,12 @@ void ConditionDialog::updateBiomeSelection()
                     for (int j = 0; j < 64; j++)
                     {
                         if (mL & (1ULL << j))
-                            tip += QString("\n") + getBiomeDisplay(mc, j);
+                            tip += QString("\n") + getBiomeDisplay(wi.mc, j);
                     }
                     for (int j = 0; j < 64; j++)
                     {
                         if (mM & (1ULL << j))
-                            tip += QString("\n") + getBiomeDisplay(mc, j+128);
+                            tip += QString("\n") + getBiomeDisplay(wi.mc, j+128);
                     }
                     cb->setToolTip(tip);
                 }
@@ -719,12 +746,12 @@ void ConditionDialog::updateBiomeSelection()
     {
         for (const auto& it : biomecboxes)
         {
-            if (isOverworld(mc, it.first))
+            if (isOverworld(wi.mc, it.first))
                 available.push_back(it.first);
         }
     }
 
-    IdCmp cmp = {IdCmp::SORT_LEX, mc, DIM_UNDEF};
+    IdCmp cmp = {IdCmp::SORT_LEX, wi.mc, DIM_UNDEF};
     std::sort(available.begin(), available.end(), cmp);
 
     if (ui->stackedWidget->currentWidget() == ui->pageBiomes)
@@ -772,7 +799,7 @@ void ConditionDialog::updateBiomeSelection()
 
         for (int id: available)
         {
-            QString s = getBiomeDisplay(mc, id);
+            QString s = getBiomeDisplay(wi.mc, id);
             ui->comboMatchBiome->addItem(getBiomeIcon(id), s, QVariant::fromValue(id));
             allowed_matches.append(s);
         }
@@ -785,7 +812,7 @@ void ConditionDialog::updateBiomeSelection()
             }
             else
             {
-                QString s = QString("%1 %2").arg(WARNING_CHAR).arg(getBiomeDisplay(mc, curid.toInt()));
+                QString s = QString("%1 %2").arg(WARNING_CHAR).arg(getBiomeDisplay(wi.mc, curid.toInt()));
                 ui->comboMatchBiome->insertItem(0, getBiomeIcon(curid.toInt(), true), s, curid);
                 ui->comboMatchBiome->setCurrentIndex(0);
                 allowed_matches.append(s);
@@ -830,21 +857,25 @@ int ConditionDialog::warnIfBad(Condition cond)
     }
     else if (cond.type == F_BIOME_CENTER || cond.type == F_BIOME_CENTER_256)
     {
-        int w = cond.x2 - cond.x1 + 1;
-        int h = cond.z2 - cond.z1 + 1;
+        int s = ft.pow2;
+        int w = (cond.x2 >> s) - (cond.x1 >> s) + 1;
+        int h = (cond.z2 >> s) - (cond.z1 >> s) + 1;
         if ((unsigned int)(w * h) < cond.count * cond.biomeSize)
         {
             QString text = tr(
-                "The biome locator checks for %1 instances of size %2 each, "
-                "which cannot be satisfied by an area of size %3%4%5 = %6.")
-                .arg(cond.count).arg(cond.biomeSize).arg(w).arg(QChar(0xD7)).arg(h).arg(w * h);
+                "The biome locator checks for %n instance(s), each of size %1, "
+                "which cannot be satisfied by an area of size\n"
+                "%2%3%4 = %5 < %6 @ scale 1:%7.", "", cond.count)
+                    .arg(cond.biomeSize)
+                    .arg(w).arg(QChar(0xD7)).arg(h).arg(w*h)
+                    .arg(cond.count * cond.biomeSize).arg(1<= MC_1_18)
+        if (wi.mc >= MC_1_18)
         {
             uint64_t m = cond.biomeToFindM;
             uint64_t underground =
@@ -890,8 +921,8 @@ void ConditionDialog::onAccept()
 
     Condition c = cond;
     c.version = Condition::VER_CURRENT;
-    c.type = ui->comboBoxType->currentData().toInt();
-    c.relative = ui->comboBoxRelative->currentData().toInt();
+    c.type = ui->comboType->currentData().toInt();
+    c.relative = ui->comboRelative->currentData().toInt();
     c.count = ui->spinBox->value();
     c.skipref = ui->checkSkipRef->isChecked();
 
@@ -923,19 +954,21 @@ void ConditionDialog::onAccept()
         c.z2 = ui->lineEditZ2->text().toInt();
     }
 
-    if (ft.area)
+    if (ft.loc & FilterInfo::LOC_2)
     {
         if (c.x1 > c.x2) std::swap(c.x1, c.x2);
         if (c.z1 > c.z2) std::swap(c.z1, c.z2);
     }
 
-    if (ui->checkRadius->isChecked())
+    if (ui->checkRadius->isEnabled() && ui->checkRadius->isChecked())
         c.rmax = ui->lineRadius->text().toInt() + 1;
     else
         c.rmax = 0;
 
     c.y = ui->comboY->currentText().section(' ', 0, 0).toInt();
 
+    c.step = ui->lineSpiralStep->text().toUShort();
+
     if (ui->stackedWidget->currentWidget() == ui->pageBiomes)
     {
         c.biomeToFind = c.biomeToFindM = 0;
@@ -959,7 +992,9 @@ void ConditionDialog::onAccept()
                 }
             }
         }
-        c.count = 0;
+        c.count = ui->checkSamplePos->isChecked() ? 1 : 0;
+        c.converage = ui->lineCoverage->text().toFloat() / 100.0;
+        c.confidence = ui->lineConfidence->text().toFloat() / 100.0;
     }
     if (ui->stackedWidget->currentWidget() == ui->pageBiomeCenter)
     {
@@ -1029,17 +1064,18 @@ void ConditionDialog::onAccept()
     close();
 }
 
-void ConditionDialog::on_comboBoxType_activated(int)
+void ConditionDialog::on_comboType_activated(int)
 {
     updateMode();
 }
 
-void ConditionDialog::on_comboBoxRelative_activated(int)
+void ConditionDialog::on_comboRelative_activated(int)
 {
     QPalette pal;
-    if (ui->comboBoxRelative->currentText().contains(WARNING_CHAR))
+    if (ui->comboRelative->currentText().contains(WARNING_CHAR))
         pal.setColor(QPalette::Normal, QPalette::Button, QColor(255,0,0,127));
-    ui->comboBoxRelative->setPalette(pal);
+    ui->comboRelative->setPalette(pal);
+    updateMode();
 }
 
 void ConditionDialog::on_buttonUncheck_clicked()
@@ -1073,21 +1109,34 @@ void ConditionDialog::on_buttonAreaInfo_clicked()
         "
"
         "Alternatively, the area can be defined as a centered square "
         "with a certain side length. In this case the area has the bounds: "
-        "[-X/2, -X/2] on both axes, rounding down and bounds included. For "
+        "[-X/2, +X/2] on both axes, rounding down and bounds included. For "
         "example a centered square with side 3 will go from -2 to 1 for both "
         "the X and Z axes."
         "
"
         "Important to note is that some filters have a scaling associated with "
-        "them. This means that the area is not defined in blocks, but on a grid "
-        "with the given spacing (such as chunks instead of blocks). A scaling "
-        "of 1:16, for example, means that the aforementioned centered square of "
-        "side 3 will range from -32 to 31 in block coordinates. (Chunk 1 has "
-        "blocks 16 to 31.)"
+        "them. This means the condition only checks on a grid with that spacing. "
+        "An area with a range from -21 to 21 at scale 1:16 may effectively be "
+        "expanded to -32 to 31, and get sampled at -32, -16, 0 and 16."
         "
"
         ));
     mb.exec();
 }
 
+void ConditionDialog::on_buttonFromVisible_clicked()
+{
+    if (!mapview)
+        return;
+    int x1, z1, x2, z2;
+    mapview->getVisible(&x1, &z1, &x2, &z2);
+    ui->lineEditX1->setText(QString::number(x1));
+    ui->lineEditZ1->setText(QString::number(z1));
+    ui->lineEditX2->setText(QString::number(x2));
+    ui->lineEditZ2->setText(QString::number(z2));
+    ui->checkRadius->setChecked(false);
+    ui->radioCustom->setChecked(true);
+    updateMode();
+}
+
 void ConditionDialog::on_checkRadius_toggled(bool)
 {
     updateMode();
@@ -1121,15 +1170,15 @@ void ConditionDialog::on_ConditionDialog_finished(int result)
     item = 0;
 }
 
-void ConditionDialog::on_comboBoxCat_currentIndexChanged(int)
+void ConditionDialog::on_comboCat_currentIndexChanged(int)
 {
-    int cat = ui->comboBoxCat->currentData().toInt();
-    ui->comboBoxType->setEnabled(cat != CAT_NONE);
-    ui->comboBoxType->clear();
+    int cat = ui->comboCat->currentData().toInt();
+    ui->comboType->setEnabled(cat != CAT_NONE);
+    ui->comboType->clear();
 
     int slot = 0;
-    ui->comboBoxType->insertItem(slot, tr("Select type"), QVariant::fromValue((int)F_SELECT));
-    ui->comboBoxType->insertSeparator(++slot);
+    ui->comboType->insertItem(slot, tr("Select type"), QVariant::fromValue((int)F_SELECT));
+    ui->comboType->insertSeparator(++slot);
 
     const FilterInfo *ft_list[FILTER_MAX] = {};
     const FilterInfo *ft;
@@ -1150,16 +1199,16 @@ void ConditionDialog::on_comboBoxCat_currentIndexChanged(int)
         QVariant vidx = QVariant::fromValue((int)(ft - g_filterinfo.list));
         QString txt = QApplication::translate("Filter", ft->name);
         if (ft->icon)
-            ui->comboBoxType->insertItem(slot, getPix(ft->icon), txt, vidx);
+            ui->comboType->insertItem(slot, getPix(ft->icon), txt, vidx);
         else
-            ui->comboBoxType->insertItem(slot, txt, vidx);
+            ui->comboType->insertItem(slot, txt, vidx);
 
-        if (mc < ft->mcmin || mc > ft->mcmax)
-            ui->comboBoxType->setItemData(slot, false, Qt::UserRole-1); // deactivate
+        if (wi.mc < ft->mcmin || wi.mc > ft->mcmax)
+            ui->comboType->setItemData(slot, false, Qt::UserRole-1); // deactivate
         if (ft == g_filterinfo.list + F_FORTRESS)
-            ui->comboBoxType->insertSeparator(slot++);
+            ui->comboType->insertSeparator(slot++);
         if (ft == g_filterinfo.list + F_ENDCITY)
-            ui->comboBoxType->insertSeparator(slot++);
+            ui->comboType->insertSeparator(slot++);
     }
 
     updateMode();
@@ -1253,8 +1302,8 @@ void ConditionDialog::onClimateLimitChanged()
 
     getClimateLimits(limok, limex);
 
-    getPossibleBiomesForLimits(ok, mc, limok);
-    getPossibleBiomesForLimits(ex, mc, limex);
+    getPossibleBiomesForLimits(ok, wi.mc, limok);
+    getPossibleBiomesForLimits(ex, wi.mc, limex);
 
     for (auto& it : noisebiomes)
     {
@@ -1270,7 +1319,7 @@ void ConditionDialog::onClimateLimitChanged()
 
 void ConditionDialog::on_lineBiomeSize_textChanged(const QString &)
 {
-    int filterindex = ui->comboBoxType->currentData().toInt();
+    int filterindex = ui->comboType->currentData().toInt();
     double area = ui->lineBiomeSize->text().toInt();
     QString s;
     if (filterindex == F_BIOME_CENTER_256)
@@ -1368,7 +1417,7 @@ void ConditionDialog::on_pushLuaSaveAs_clicked()
     stream.flush();
     file.close();
     ui->textEditLua->document()->setModified(false);
-    uint64_t hash = getScriptHash(fnam);
+    uint64_t hash = getScriptHash(QFileInfo(fnam));
     ui->comboLua->addItem(QFileInfo(fnam).baseName(), QVariant::fromValue(hash));
     ui->comboLua->setCurrentIndex(ui->comboLua->count() - 1);
 }
@@ -1495,17 +1544,21 @@ void ConditionDialog::on_comboClimatePara_currentIndexChanged(int)
 {
     ui->comboOctaves->clear();
     int loptidx = LOPT_NOISE_PARA + ui->comboClimatePara->currentData().toInt();
-    QStringList items;
     for (int i = 0; ; i++)
     {
-        if (const char *s = getLayerOptionText(loptidx, i))
-            items.append(s);
-        else
+        LayerOptInfo info;
+        if (!getLayerOptionInfo(&info, loptidx, i, wi))
             break;
+        ui->comboOctaves->addItem(info.summary);
+        ui->comboOctaves->setItemData(ui->comboOctaves->count()-1, info.tooltip, Qt::ToolTipRole);
     }
-    ui->comboOctaves->addItems(items);
+    on_comboOctaves_currentIndexChanged(0);
 }
 
+void ConditionDialog::on_comboOctaves_currentIndexChanged(int)
+{
+    ui->comboOctaves->setToolTip(ui->comboOctaves->currentData(Qt::ToolTipRole).toString());
+}
 
 void ConditionDialog::on_comboY_currentTextChanged(const QString &text)
 {
diff --git a/src/conditiondialog.h b/src/conditiondialog.h
index 71e80a2..87ea0e2 100644
--- a/src/conditiondialog.h
+++ b/src/conditiondialog.h
@@ -19,6 +19,7 @@
 #include 
 
 class MainWindow;
+class MapView;
 
 namespace Ui {
 class ConditionDialog;
@@ -180,7 +181,7 @@ class ConditionDialog : public QDialog
 
 public:
 
-    explicit ConditionDialog(FormConditions *parent, Config *config, int mc, QListWidgetItem *item = 0, Condition *initcond = 0);
+    explicit ConditionDialog(FormConditions *parent, MapView *mapview, Config *config, WorldInfo wi, QListWidgetItem *item = 0, Condition *initcond = 0);
     virtual ~ConditionDialog();
 
     void addTempCat(int temp, QString name);
@@ -199,15 +200,16 @@ signals:
     void setCond(QListWidgetItem *item, Condition cond, int modified);
 
 private slots:
-    void on_comboBoxType_activated(int);
+    void on_comboType_activated(int);
 
-    void on_comboBoxRelative_activated(int);
+    void on_comboRelative_activated(int);
 
     void on_buttonUncheck_clicked();
     void on_buttonInclude_clicked();
     void on_buttonExclude_clicked();
 
     void on_buttonAreaInfo_clicked();
+    void on_buttonFromVisible_clicked();
 
     void on_checkRadius_toggled(bool checked);
     void on_radioSquare_toggled(bool checked);
@@ -218,7 +220,7 @@ private slots:
 
     void on_ConditionDialog_finished(int result);
 
-    void on_comboBoxCat_currentIndexChanged(int);
+    void on_comboCat_currentIndexChanged(int);
 
     void onCheckStartChanged(int state);
     void onClimateLimitChanged();
@@ -236,6 +238,7 @@ private slots:
     void on_pushInfoLua_clicked();
 
     void on_comboClimatePara_currentIndexChanged(int index);
+    void on_comboOctaves_currentIndexChanged(int index);
 
     void on_comboY_currentTextChanged(const QString &text);
     void on_comboY2_currentTextChanged(const QString &text);
@@ -255,10 +258,11 @@ private:
     uint64_t luahash;
 
 public:
+    MapView *mapview;
     Config *config;
     QListWidgetItem *item;
     Condition cond;
-    int mc;
+    WorldInfo wi;
 };
 
 #endif // CONDITIONDIALOG_H
diff --git a/src/conditiondialog.ui b/src/conditiondialog.ui
index 62a786e..55b7ec6 100644
--- a/src/conditiondialog.ui
+++ b/src/conditiondialog.ui
@@ -13,7 +13,7 @@
    
     
      
-      
+      
        
         
          2
@@ -26,7 +26,7 @@
       
      
      
-      
+      
        
         false
        
@@ -256,6 +256,13 @@
               
              
             
+            
+             
+              
+               From visible
+              
+             
+            
            
           
           
@@ -344,7 +351,7 @@ QPushButton:hover {
            
           
           
-           
+           
             
              QComboBox::AdjustToContentsOnFirstShow
             
@@ -388,7 +395,7 @@ QPushButton:hover {
           0
          
          
-          5
+          1
          
          
           
@@ -460,47 +467,7 @@ QPushButton:hover {
               Biomes
              
              
-              
-               
-                
-                 Enables optimizations that trade some accuracy for speed
-                
-                
-                 Approximate
-                
-               
-              
-              
-               
-                
-                 <html><head/><body><p style="white-space:pre">Satisfied if <span style=" font-weight:600;">any</span> of the checked biomes are present</p></body></html>
-                
-                
-                 Match any
-                
-               
-              
-              
-               
-                
-                 Qt::Horizontal
-                
-                
-                 
-                  0
-                  0
-                 
-                
-               
-              
-              
-               
-                
-                 Sample at height (Y):
-                
-               
-              
-              
+              
                
                 
                  true
@@ -565,7 +532,24 @@ QPushButton:hover {
                 
                
               
-              
+              
+               
+                
+                 true
+                
+                
+                 
+                  
+                   QLayout::SetMinAndMaxSize
+                  
+                  
+                   
+                  
+                 
+                
+               
+              
+              
                
                 
                  
@@ -590,21 +574,128 @@ QPushButton:hover {
                 
                
               
-              
-               
-                
-                 true
+              
+               
+                
+                 Qt::Horizontal
                 
-                
-                 
-                  
-                   QLayout::SetMinAndMaxSize
+                
+                 
+                  0
+                  0
+                 
+                
+               
+              
+              
+               
+                
+                 
+                  0
+                  0
+                 
+                
+                
+                 0
+                
+                
+                 
+                  
+                   0
+                   0
+                  
+                 
+                 
+                  
+                   0
                   
-                  
-                   
+                  
+                   0
+                  
+                  
+                   0
+                  
+                  
+                   0
+                  
+                  
+                   
+                    
+                     <html><head/><body><p style="white-space:pre">Satisfied if <span style=" font-weight:600;">any</span> of the checked biomes are present</p></body></html>
+                    
+                    
+                     Match any
+                    
+                   
+                  
+                  
+                   
+                    
+                     Enables optimizations that trade some accuracy for speed
+                    
+                    
+                     Approximate
+                    
+                   
                   
                  
                 
+                
+                 
+                  
+                   0
+                   0
+                  
+                 
+                 
+                  
+                   0
+                  
+                  
+                   0
+                  
+                  
+                   0
+                  
+                  
+                   0
+                  
+                  
+                   
+                    
+                     Coverage (%):
+                    
+                   
+                  
+                  
+                   
+                    
+                     Confidence (%):
+                    
+                   
+                  
+                  
+                   
+                    
+                     Yield positions
+                    
+                   
+                  
+                  
+                   
+                  
+                  
+                   
+                  
+                 
+                
+               
+              
+              
+               
+                
+                 Sample at height (Y):
+                
                
               
              
@@ -1325,6 +1416,58 @@ QPushButton:hover {
            
           
          
+         
+          
+           
+            0
+           
+           
+            0
+           
+           
+            0
+           
+           
+            0
+           
+           
+            
+             
+              Spiral iterator
+             
+             
+              
+               
+                
+                 Step size:
+                
+               
+              
+              
+               
+                
+                 512
+                
+               
+              
+              
+               
+                
+                 Qt::Vertical
+                
+                
+                 
+                  20
+                  40
+                 
+                
+               
+              
+             
+            
+           
+          
+         
          
           
            
@@ -1669,14 +1812,14 @@ QPushButton:hover {
   
  
  
-  comboBoxCat
-  comboBoxType
+  comboCat
+  comboType
   spinBox
   lineEditX1
   lineEditZ1
   lineEditX2
   lineEditZ2
-  comboBoxRelative
+  comboRelative
   stackedWidget
  
  
diff --git a/src/configdialog.cpp b/src/configdialog.cpp
index d8080da..6c6f787 100644
--- a/src/configdialog.cpp
+++ b/src/configdialog.cpp
@@ -52,7 +52,9 @@ ConfigDialog::ConfigDialog(QWidget *parent, Config *config)
     int hsc = ui->scrollAreaWidgetContents->sizeHint().height();
     int hpa = parent->size().height();
     int h = size.height();
-    h += hsc - hsa + layout()->margin();
+    int m1, m2;
+    layout()->getContentsMargins(0, &m1, 0, &m2);
+    h += hsc - hsa + m1 + m2;
     if (h > hpa) h = hpa;
     size.setHeight(h);
     resize(size);
diff --git a/src/formconditions.cpp b/src/formconditions.cpp
index 0e1aa8b..7eaca9f 100644
--- a/src/formconditions.cpp
+++ b/src/formconditions.cpp
@@ -75,7 +75,7 @@ FormConditions::FormConditions(QWidget *parent)
     }
 
     qRegisterMetaType< Condition >("Condition");
-    qRegisterMetaTypeStreamOperators< Condition >("Condition");
+//    qRegisterMetaTypeStreamOperators< Condition >("Condition");
 }
 
 FormConditions::~FormConditions()
@@ -117,10 +117,12 @@ void FormConditions::updateSensitivity()
         ui->buttonEdit->setEnabled(false);
     }
 
+    QVector selcond;
     int disabled = 0;
     for (int i = 0; i < selected.size(); i++)
     {
         Condition c = qvariant_cast(selected[i]->data(Qt::UserRole));
+        selcond.append(c);
         if (c.meta & Condition::DISABLED)
             disabled++;
     }
@@ -131,6 +133,8 @@ void FormConditions::updateSensitivity()
     else
         ui->buttonDisable->setText(tr("Toggle"));
     ui->buttonDisable->setEnabled(!selected.empty());
+
+    emit selectionUpdate(selcond);
 }
 
 
@@ -207,7 +211,7 @@ void FormConditions::editCondition(QListWidgetItem *item)
         return;
     WorldInfo wi;
     parent->getSeed(&wi);
-    ConditionDialog *dialog = new ConditionDialog(this, &parent->config, wi.mc, item, (Condition*)item->data(Qt::UserRole).data());
+    ConditionDialog *dialog = new ConditionDialog(this, parent->getMapView(), &parent->config, wi, item, (Condition*)item->data(Qt::UserRole).data());
     QObject::connect(dialog, SIGNAL(setCond(QListWidgetItem*,Condition,int)), this, SLOT(addItemCondition(QListWidgetItem*,Condition,int)), Qt::QueuedConnection);
     dialog->show();
 }
@@ -266,7 +270,7 @@ void FormConditions::on_buttonAddFilter_clicked()
         return;
     WorldInfo wi;
     parent->getSeed(&wi);
-    ConditionDialog *dialog = new ConditionDialog(this, &parent->config, wi.mc);
+    ConditionDialog *dialog = new ConditionDialog(this, parent->getMapView(), &parent->config, wi);
     QObject::connect(dialog, SIGNAL(setCond(QListWidgetItem*,Condition,int)), this, SLOT(addItemCondition(QListWidgetItem*,Condition)), Qt::QueuedConnection);
     dialog->show();
 }
diff --git a/src/formconditions.h b/src/formconditions.h
index d0d3d9c..b22e1ab 100644
--- a/src/formconditions.h
+++ b/src/formconditions.h
@@ -44,6 +44,7 @@ public:
 
 signals:
     void changed();
+    void selectionUpdate(const QVector& selected);
 
 public slots:
     void on_buttonRemoveAll_clicked();
diff --git a/src/formsearchcontrol.cpp b/src/formsearchcontrol.cpp
index 44db4c7..6850aa9 100644
--- a/src/formsearchcontrol.cpp
+++ b/src/formsearchcontrol.cpp
@@ -487,21 +487,21 @@ void FormSearchControl::on_buttonSearchHelp_clicked()
     mb.setText(tr(
         "
"
         "The incremental search checks seeds in numerical order, "
-        "save for grouping into work items for parallelization. This type "
-        "of search is best suited for a non-exhaustive search space and "
-        "with strong biome dependencies. You can restrict this type of "
-        "search to a value range using the "..." button."
+        "except for grouping seeds into work items for parallelization. "
+        "This is the recommended option for general searches. You can "
+        "restrict this type of search to a value range using the "
+        ""..." button."
         "
"
-        "When searching 48-bit only, the search is limited to the seed "
-        "bases and does not yield matching seeds, but rather checks only the "
-        "parts of the conditions can be determined from the lower 48-bits. "
-        "Sessions saved from this search are suitable to be used later with "
-        "the 48-bit generator to look for matching seeds."
+        "When using 48-bit only, the search checks partial seeds and "
+        "will not test the full conditions. Instead it yields seed bases "
+        "that may satify the conditions without knowing the upper 16-bit of "
+        "the seed. A session file saved from this search is suitable to be used "
+        "later with the 48-bit generator to look for matching seeds."
         "
"
         "With 48-bit family blocks the search looks for suitable "
         "48-bit seeds first and parallelizes the search through the upper "
-        "16-bits. This search type is best suited for exhaustive searches and "
-        "those with very restrictive structure requirements."
+        "16-bits. This search type can be a better match for exhaustive searches "
+        "and those with very restrictive structure requirements."
         "
"
         "Load a seed list from a file to search through an "
         "existing set of seeds. The seeds should be in decimal ASCII text, "
@@ -585,7 +585,7 @@ void FormSearchControl::searchResult(uint64_t seed)
     qbuf.push_back(seed);
     if (ui->checkStop->isChecked())
     {
-        onBufferTimeout();
+        stopSearch();
         return;
     }
 
diff --git a/src/formsearchcontrol.h b/src/formsearchcontrol.h
index 085c57b..8bc2f83 100644
--- a/src/formsearchcontrol.h
+++ b/src/formsearchcontrol.h
@@ -8,6 +8,7 @@
 #include 
 #include 
 #include 
+#include 
 
 #include 
 
diff --git a/src/formsearchcontrol.ui b/src/formsearchcontrol.ui
index d971f9c..72cec37 100644
--- a/src/formsearchcontrol.ui
+++ b/src/formsearchcontrol.ui
@@ -167,7 +167,7 @@ QPushButton:hover {
         
        
        
-        Queued progress within search set
+        Queued progress within the search set
        
        
         Qt::LeftToRight
diff --git a/src/gotodialog.cpp b/src/gotodialog.cpp
index a7d42c6..46d5d43 100644
--- a/src/gotodialog.cpp
+++ b/src/gotodialog.cpp
@@ -74,7 +74,7 @@ void GotoDialog::keyPressEvent(QKeyEvent *event)
     {
         QClipboard *clipboard = QGuiApplication::clipboard();
         QString s = clipboard->text().trimmed();
-        QStringList xz = s.split(QRegExp("[, ]+"));
+        QStringList xz = s.split(QRegularExpression("[, ]+"));
         if (xz.count() == 2)
         {
             ui->lineX->setText(xz[0]);
diff --git a/src/layerdialog.cpp b/src/layerdialog.cpp
index 6a9c0ff..aa23d24 100644
--- a/src/layerdialog.cpp
+++ b/src/layerdialog.cpp
@@ -5,125 +5,96 @@
 
 #include 
 
-const char *getLayerOptionText(int mode, int disp)
+bool getLayerOptionInfo(LayerOptInfo *info, int mode, int disp, WorldInfo wi)
 {
-    /*
-    Para 0:
-      4096   0.952381
-      1024   0.158730
-    Para 1:
-      1024   0.564374
-       512   0.282187
-    Para 2:
-      2048   0.751468
-      1024   0.375734
-       512   0.375734
-       256   0.187867
-       128   0.093933
-        64   0.023483
-        32   0.011742
-        16   0.005871
-         8   0.002935
-    Para 3:
-      2048   0.716846
-      1024   0.358423
-       256   0.089606
-       128   0.044803
-    Para 4:
-        32   0.666667
-        16   0.333333
-         8   0.166667
-    Para 5:
-       512   0.634921
-       256   0.634921
-       128   0.158730
-    */
+    QString txt;
+    QString tip;
+    int nptype = -1;
+
     switch (mode)
     {
     case LOPT_BIOMES:
-        switch (disp) {
-        case 0: return "1:1";
-        case 1: return "1:4";
-        case 2: return "1:16";
-        case 3: return "1:64";
-        case 4: return "1:256";
-        default: return nullptr;
-        }
-    case LOPT_NOISE_T_4:
-        switch (disp) {
-        case 0: return "All";
-        case 1: return "+A[0] 1:4096 x0.952381";
-        case 2: return "+B[0] 1:4023 x0.952381";
-        case 3: return "+A[1] 1:1024 x0.158730";
-        case 4: return "+B[1] 1:1005 x0.158730";
-        default: return nullptr;
-        }
-    case LOPT_NOISE_H_4:
-        switch (disp) {
-        case 0: return "All";
-        case 1: return "+A[0] 1:1024 x0.564374";
-        case 2: return "+B[0] 1:1005 x0.564374";
-        case 3: return "+A[1] 1:512  x0.282187";
-        case 4: return "+B[1] 1:502  x0.282187";
-        default: return nullptr;
-        }
-    case LOPT_NOISE_C_4:
-        switch (disp) {
-        case 0: return "All";
-        case 1: return "+A[0] 1:2048 x0.751468";
-        case 2: return "+B[0] 1:2011 x0.751468";
-        case 3: return "+A[1] 1:1024 x0.375734";
-        case 4: return "+B[1] 1:1005 x0.375734";
-        case 5: return "+A[2] 1:512  x0.375734";
-        case 6: return "+B[2] 1:502  x0.375734";
-        case 7: return "+A[3] 1:256  x0.187867";
-        case 8: return "+B[3] 1:251  x0.187867";
-        case 9: return "+A[4] 1:128  x0.093933";
-        case 10: return "+B[4] 1:125  x0.093933";
-        case 11: return "+A[5] 1:64   x0.023483";
-        case 12: return "+B[5] 1:62   x0.023483";
-        case 13: return "+A[6] 1:32   x0.011742";
-        case 14: return "+B[6] 1:31   x0.011742";
-        default: return nullptr;
-        }
-    case LOPT_NOISE_E_4:
-        switch (disp) {
-        case 0: return "All";
-        case 1: return "+A[0] 1:2048 x0.716846";
-        case 2: return "+B[0] 1:2011 x0.716846";
-        case 3: return "+A[1] 1:1024 x0.358423";
-        case 4: return "+B[1] 1:1005 x0.358423";
-        case 5: return "+A[2] 1:256  x0.089606";
-        case 6: return "+B[2] 1:251  x0.089606";
-        case 7: return "+A[3] 1:128  x0.044803";
-        case 8: return "+B[3] 1:125  x0.044803";
-        default: return nullptr;
-        }
-    case LOPT_NOISE_W_4:
-        switch (disp) {
-        case 0: return "All";
-        case 1: return "+A[0] 1:512 x0.634921";
-        case 2: return "+B[0] 1:502 x0.634921";
-        case 3: return "+A[1] 1:256 x0.634921";
-        case 4: return "+B[1] 1:251 x0.634921";
-        case 5: return "+A[2] 1:128 x0.158730";
-        case 6: return "+B[2] 1:125 x0.158730";
-        default: return nullptr;
-        }
+        if (disp == 0) txt = "1:1";
+        if (disp == 1) txt = "1:4";
+        if (disp == 2) txt = "1:16";
+        if (disp == 3) txt = "1:64";
+        if (disp == 4) txt = "1:256";
+        break;
     case LOPT_HEIGHT_4:
-        switch (disp) {
-        case 0: return QT_TRANSLATE_NOOP("LayerDialog", "Grayscale");
-        case 1: return QT_TRANSLATE_NOOP("LayerDialog", "Shaded biome map");
-        case 2: return QT_TRANSLATE_NOOP("LayerDialog", "Contours on biomes");
-        case 3: return QT_TRANSLATE_NOOP("LayerDialog", "Shaded with contours");
-        default: return nullptr;
-        }
-    default:
-        return nullptr;
+        if (disp == 0) txt = QApplication::translate("LayerDialog", "Grayscale");
+        if (disp == 1) txt = QApplication::translate("LayerDialog", "Shaded biome map");
+        if (disp == 2) txt = QApplication::translate("LayerDialog", "Contours on biomes");
+        if (disp == 3) txt = QApplication::translate("LayerDialog", "Shaded with contours");
+        break;
+    case LOPT_NOISE_T_4: nptype = NP_TEMPERATURE; break;
+    case LOPT_NOISE_H_4: nptype = NP_HUMIDITY; break;
+    case LOPT_NOISE_C_4: nptype = NP_CONTINENTALNESS; break;
+    case LOPT_NOISE_E_4: nptype = NP_EROSION; break;
+    case LOPT_NOISE_W_4: nptype = NP_WEIRDNESS; break;
     }
+
+    if (nptype != -1 && disp >= 0)
+    {
+        BiomeNoise bn;
+        initBiomeNoise(&bn, wi.mc);
+        setBiomeSeed(&bn, wi.seed, wi.large);
+
+        DoublePerlinNoise *dpn = bn.climate + nptype;
+        PerlinNoise *oct[2] = { dpn->octA.octaves, dpn->octB.octaves };
+        int noct = dpn->octA.octcnt;
+        int idx = noct-1;
+        int ab = 1;
+        if (disp > 0)
+        {
+            idx = (disp - 1) / 2;
+            ab  = (disp - 1) % 2;
+            if (idx >= noct)
+                return false;
+        }
+
+        double ampsum = 0, amptot = 0;
+        for (int i = 0; i < noct; i++)
+        {
+            for (int j = 0; j <= 1; j++)
+            {
+                double a = oct[j][i].amplitude;
+                amptot += a;
+                if (i < idx || (idx == i && j <= ab))
+                    ampsum += a;
+            }
+        }
+        amptot *= dpn->amplitude;
+        ampsum *= dpn->amplitude;
+
+        double f = 337.0 / 331.0;
+        PerlinNoise *pn = &oct[ab][idx];
+        double a = pn->amplitude * dpn->amplitude;
+        double l = pn->lacunarity * (ab == 0 ? 1.0 : f);
+
+        if (disp == 0)
+        {
+            txt += QString("%1..            x%2").arg(QChar(0x03A3)).arg(amptot, 0, 'f', 6);
+            tip += QApplication::translate("LayerDialog", "All octaves");
+        }
+        else
+        {
+            txt += QString("%1..").arg(QChar(0x03A3));
+            txt += QString::asprintf("%d%c  1:%-5.0f x%.6f", idx, ab?'B':'A', 1.0/l, a);
+            tip += QApplication::translate("LayerDialog", "Contribution of the %n most significant octaves out of %1 total.", "", disp).arg(2*noct);
+        }
+        tip += "\n" + QApplication::translate("LayerDialog", "Total contribution: %1 = %2%").arg(ampsum).arg(100 * ampsum / amptot, 0, 'f', 1);
+        tip += "\n" + QApplication::translate("LayerDialog", "Octave amplitude: %1").arg(a);
+        tip += "\n" + QApplication::translate("LayerDialog", "Octave lacunarity: %1 = 1/%2").arg(l).arg(1.0/l);
+    }
+
+    if (info) {
+        info->summary = txt;
+        info->tooltip = tip;
+    }
+    return !txt.isEmpty();
 }
 
-LayerDialog::LayerDialog(QWidget *parent, int mc)
+LayerDialog::LayerDialog(QWidget *parent, WorldInfo wi)
   : QDialog(parent)
   , ui(new Ui::LayerDialog)
   , radio{}
@@ -157,18 +128,21 @@ LayerDialog::LayerDialog(QWidget *parent, int mc)
     {
         if (!combo[i])
             continue;
-        QStringList items;
         for (int j = 0; ; j++)
         {
-            const char *item = getLayerOptionText(i, j);
-            if (!item)
+            LayerOptInfo info;
+            if (!getLayerOptionInfo(&info, i, j, wi))
                 break;
-            QString s = QApplication::translate("LayerDialog", item).leftJustified(24);
+            QString s = info.summary.leftJustified(24);
             if (j < 9)
                 s += "\tALT+"+QString::number(j+1);
-            items.append(s);
+            combo[i]->addItem(s);
+            combo[i]->setItemData(combo[i]->count()-1, info.tooltip, Qt::ToolTipRole);
         }
-        combo[i]->addItems(items);
+        connect(combo[i], QOverload::of(&QComboBox::currentIndexChanged), [=](int){
+            this->onComboChange(combo[i]);
+        });
+        onComboChange(combo[i]);
     }
 
     QFont fmono;
@@ -182,17 +156,17 @@ LayerDialog::LayerDialog(QWidget *parent, int mc)
             combo[i]->setFont(fmono);
         if (i >= LOPT_NOISE_T_4 && i <= LOPT_NOISE_W_4)
         {
-            radio[i]->setEnabled(mc > MC_1_17);
+            radio[i]->setEnabled(wi.mc > MC_1_17);
             if (combo[i])
-                combo[i]->setEnabled(mc > MC_1_17);
+                combo[i]->setEnabled(wi.mc > MC_1_17);
         }
         if (i == LOPT_RIVER_4 || i == LOPT_OCEAN_256)
         {
-            radio[i]->setEnabled(mc > MC_1_12 && mc <= MC_1_17);
+            radio[i]->setEnabled(wi.mc > MC_1_12 && wi.mc <= MC_1_17);
         }
         if (i == LOPT_NOOCEAN_1 || i == LOPT_BETA_T_1 || i == LOPT_BETA_H_1)
         {
-            radio[i]->setEnabled(mc <= MC_B1_7);
+            radio[i]->setEnabled(wi.mc <= MC_B1_7);
         }
     }
 }
@@ -235,6 +209,11 @@ void LayerDialog::onRadioChange()
     }
 }
 
+void LayerDialog::onComboChange(QComboBox *combo)
+{
+    combo->setToolTip(combo->currentData(Qt::ToolTipRole).toString());
+}
+
 void LayerDialog::on_buttonBox_clicked(QAbstractButton *button)
 {
     QDialogButtonBox::StandardButton b = ui->buttonBox->standardButton(button);
diff --git a/src/layerdialog.h b/src/layerdialog.h
index 01f985f..8979c93 100644
--- a/src/layerdialog.h
+++ b/src/layerdialog.h
@@ -11,14 +11,20 @@ namespace Ui {
 class LayerDialog;
 }
 
-const char *getLayerOptionText(int mode, int disp);
+struct LayerOptInfo
+{
+    QString summary;
+    QString tooltip;
+};
+
+bool getLayerOptionInfo(LayerOptInfo *info, int mode, int disp, WorldInfo wi);
 
 class LayerDialog : public QDialog
 {
     Q_OBJECT
 
 public:
-    explicit LayerDialog(QWidget *parent, int mc);
+    explicit LayerDialog(QWidget *parent, WorldInfo mc);
     ~LayerDialog();
 
     void setLayerOptions(LayerOpt lopts);
@@ -29,6 +35,7 @@ signals:
 
 public slots:
     void onRadioChange();
+    void onComboChange(QComboBox *combo);
 
 private slots:
     void on_buttonBox_clicked(QAbstractButton *button);
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index bf79f07..f469a54 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -10,6 +10,7 @@
 #include "exportdialog.h"
 #include "layerdialog.h"
 #include "tabtriggers.h"
+#include "tablocations.h"
 #include "tabbiomes.h"
 #include "tabstructures.h"
 #include "message.h"
@@ -52,7 +53,8 @@ MainWindow::MainWindow(QString sessionpath, QString resultspath, QWidget *parent
     , sessionpath(sessionpath)
     , prevdir(".")
     , autosaveTimer()
-    , prevtab(-1)
+    , tabidx(-1)
+    , tabsearch(-1)
     , dimactions{}
     , dimgroup()
 {
@@ -86,7 +88,8 @@ MainWindow::MainWindow(QString sessionpath, QString resultspath, QWidget *parent
 
     ui->menuHistory->clear();
 
-    ui->tabContainer->addTab(new TabTriggers(this), tr("Triggers"));
+    ui->tabContainerSearch->addTab(new TabTriggers(this), tr("Triggers"));
+    ui->tabContainerSearch->addTab(new TabLocations(this), tr("Locations"));
     ui->tabContainer->addTab(new TabBiomes(this), tr("Biomes"));
     ui->tabContainer->addTab(new TabStructures(this), tr("Structures"));
 
@@ -185,7 +188,8 @@ MainWindow::MainWindow(QString sessionpath, QString resultspath, QWidget *parent
     saction[D_GRID]->setChecked(true);
 
     ui->splitterMap->setSizes(QList({6500, 10000}));
-    ui->splitterSearch->setSizes(QList({1000, 1000, 2000}));
+    ui->splitterSearch->setSizes(QList({1000, 3000}));
+    ui->splitterSeeds->setSizes(QList({500, 2500}));
 
     qRegisterMetaType< int64_t >("int64_t");
     qRegisterMetaType< uint64_t >("uint64_t");
@@ -202,6 +206,7 @@ MainWindow::MainWindow(QString sessionpath, QString resultspath, QWidget *parent
 
     ui->collapseConstraints->init(tr("Conditions"), formCond, false);
     connect(formCond, &FormConditions::changed, this, &MainWindow::onConditionsChanged);
+    connect(formCond, &FormConditions::selectionUpdate, this, &MainWindow::onConditionsSelect);
     ui->collapseConstraints->setInfo(
         tr("Help: Conditions"),
         tr(
@@ -304,7 +309,7 @@ bool MainWindow::loadTranslation(QString lang)
     static QTranslator qt_translator;
     if (!rc_translator.load(lang, ":/lang"))
         return false;
-    QLocale::setDefault(lang);
+    QLocale::setDefault(QLocale(lang));
     QString qt_locale = "qtbase_" + lang;
     QString qt_trpath = QLibraryInfo::location(QLibraryInfo::TranslationsPath);
     if (qt_translator.load(qt_locale, qt_trpath))
@@ -432,8 +437,9 @@ bool MainWindow::setSeed(WorldInfo wi, int dim)
     ui->seedEdit->setEnabled(true);
     ui->comboY->setEnabled(true);
 
-    ISaveTab *tab = dynamic_cast(ui->tabContainer->currentWidget());
-    if (tab)
+    if (ISaveTab *tab = dynamic_cast(ui->tabContainer->currentWidget()))
+        tab->refresh();
+    if (ISaveTab *tab = dynamic_cast(ui->tabContainerSearch->currentWidget()))
         tab->refresh();
     return true;
 }
@@ -466,6 +472,7 @@ void MainWindow::saveSettings()
     g_extgen.save(settings);
 
     on_tabContainer_currentChanged(-1);
+    on_tabContainerSearch_currentChanged(-1);
 
     WorldInfo wi;
     getSeed(&wi, false);
@@ -497,7 +504,7 @@ void MainWindow::loadSettings()
         showMaximized();
     } else {
         resize(settings.value("mainwindow/size", size()).toSize());
-        move(settings.value("mainwindow/pos", pos()).toPoint());
+        //move(settings.value("mainwindow/pos", pos()).toPoint());
     }
     prevdir = settings.value("mainwindow/prevdir", prevdir).toString();
 
@@ -635,7 +642,7 @@ void MainWindow::setDockable(bool dockable)
         // and avoid a warning about negative size widget
         QWidget *title = new QWidget(this);
         QHBoxLayout *l = new QHBoxLayout(title);
-        l->setMargin(0);
+        l->setContentsMargins(0, 0, 0, 0);
         title->setLayout(l);
         dock->setTitleBarWidget(title);
         dock->setFloating(false);
@@ -885,7 +892,7 @@ void MainWindow::on_actionLayerDisplay_triggered()
 {
     WorldInfo wi;
     getSeed(&wi, false);
-    LayerDialog *dialog = new LayerDialog(this, wi.mc);
+    LayerDialog *dialog = new LayerDialog(this, wi);
     dialog->setLayerOptions(lopt);
     connect(dialog, &LayerDialog::apply, [=](){
         lopt = dialog->getLayerOptions();
@@ -895,14 +902,24 @@ void MainWindow::on_actionLayerDisplay_triggered()
     dialog->show();
 }
 
-void MainWindow::on_tabContainer_currentChanged(int index)
+static int tab_switch(QTabWidget *tabs, int idxprev, int idxnext)
 {
     QSettings settings(APP_STRING, APP_STRING);
-    ISaveTab *tabold = dynamic_cast(ui->tabContainer->widget(prevtab));
-    ISaveTab *tabnew = dynamic_cast(ui->tabContainer->widget(index));
+    ISaveTab *tabold = dynamic_cast(tabs->widget(idxprev));
+    ISaveTab *tabnew = dynamic_cast(tabs->widget(idxnext));
     if (tabold) tabold->save(settings);
     if (tabnew) tabnew->load(settings);
-    prevtab = index;
+    return idxnext;
+}
+
+void MainWindow::on_tabContainer_currentChanged(int index)
+{
+    tabidx = tab_switch(ui->tabContainer, tabidx, index);
+}
+
+void MainWindow::on_tabContainerSearch_currentChanged(int index)
+{
+    tabsearch = tab_switch(ui->tabContainerSearch, tabsearch, index);
 }
 
 void MainWindow::on_actionSearch_seed_list_triggered()
@@ -946,16 +963,16 @@ void MainWindow::onActionMapToggled(int sopt, bool show)
 
 void MainWindow::onActionBiomeLayerSelect(int mode, int disp)
 {
+    WorldInfo wi;
+    getSeed(&wi, false);
+    lopt.mode = mode;
     if (disp >= 0)
     {
-        if (!getLayerOptionText(mode, disp))
+        if (!getLayerOptionInfo(nullptr, mode, disp, wi))
             return; // unsupported display mode
         lopt.disp[mode] = disp;
     }
-    lopt.mode = mode;
-    WorldInfo wi;
-    if (getSeed(&wi, false))
-        setSeed(wi, DIM_UNDEF);
+    setSeed(wi, DIM_UNDEF);
 }
 
 void MainWindow::onConditionsChanged()
@@ -964,6 +981,37 @@ void MainWindow::onConditionsChanged()
     formGen48->updateAutoConditions(conds);
 }
 
+void MainWindow::onConditionsSelect(const QVector& selection)
+{
+    std::vector shapes;
+    for (const Condition& c : selection)
+    {
+        if (c.meta & Condition::DISABLED)
+            continue;
+        if (c.relative)
+            continue;
+        const FilterInfo& ft = g_filterinfo.list[c.type];
+
+        Shape s;
+        s.dim = ft.dim;
+        if (c.rmax)
+        {
+            s.type = Shape::CIRCLE;
+            s.p1 = s.p2 = Pos{0,0};
+            s.r = c.rmax - 1;
+        }
+        else
+        {
+            s.type = Shape::RECT;
+            s.p1 = Pos{c.x1, c.z1};
+            s.p2 = Pos{c.x2+1, c.z2+1};
+            s.r = 0;
+        }
+        shapes.push_back(s);
+    }
+    getMapView()->setShapes(shapes);
+}
+
 void MainWindow::onGen48Changed()
 {
     formGen48->updateCount();
diff --git a/src/mainwindow.h b/src/mainwindow.h
index 5171e0a..027d6c6 100644
--- a/src/mainwindow.h
+++ b/src/mainwindow.h
@@ -103,6 +103,7 @@ private slots:
     void on_actionLayerDisplay_triggered();
 
     void on_tabContainer_currentChanged(int index);
+    void on_tabContainerSearch_currentChanged(int index);
 
     void on_actionSearch_seed_list_triggered();
     void on_actionSearch_full_seed_space_triggered();
@@ -113,6 +114,7 @@ private slots:
     void onActionHistory(QAction *act);
     void onActionBiomeLayerSelect(int lopt, int disp = -1);
     void onConditionsChanged();
+    void onConditionsSelect(const QVector& selection);
     void onGen48Changed();
     void onSelectedSeedChanged(uint64_t seed);
     void onSearchStatusChanged(bool running);
@@ -136,7 +138,8 @@ public:
     QString sessionpath;
     QString prevdir;
     QTimer autosaveTimer;
-    int prevtab;
+    int tabidx;
+    int tabsearch;
 
     QVector laction;
     QVector saction;
diff --git a/src/mainwindow.ui b/src/mainwindow.ui
index 11a419a..44f22ee 100644
--- a/src/mainwindow.ui
+++ b/src/mainwindow.ui
@@ -211,6 +211,11 @@
         
         
          
+          
+           QToolButton {
+ 	background-color: transparent;
+}
+          
           
            0
           
@@ -224,120 +229,68 @@
            
             Search
            
-           
+           
             
              0
             
-            
-             0
-            
-            
-             0
-            
-            
-             0
-            
-            
-             0
-            
             
-             
-              
-               
-                540
-                0
-               
+             
+              
+               Qt::Vertical
               
-              
-               QAbstractScrollArea#scrollArea {
- 	border: 0px none;
-}
-
-QToolButton {
- 	background-color: transparent;
-}
-              
-              
-               QFrame::NoFrame
-              
-              
-               QFrame::Plain
-              
-              
-               0
-              
-              
-               Qt::ScrollBarAsNeeded
-              
-              
-               Qt::ScrollBarAlwaysOff
-              
-              
-               true
-              
-              
-               Qt::AlignLeading|Qt::AlignLeft|Qt::AlignTop
-              
-              
+              
                
-                
+                
                  0
                  0
                 
                
-               
-                
-                 440
-                 0
-                
-               
-               
+              
+              
+               
                 
-                 0
-                
-                
-                 0
+                 18
                 
                 
-                 
-                  
-                   
-                    0
-                    0
-                   
+                 
+                  
+                   0
                   
-                  
-                   
-QSplitter {
-  background-color: transparent;
-}
-                  
-                  
-                   Qt::Vertical
-                  
-                  
-                   
-                    
-                     0
-                     0
-                    
-                   
-                  
-                  
-                   
-                    
-                     0
-                     0
-                    
-                   
-                  
-                  
-                   
-                    
-                     0
-                     0
-                    
-                   
+                  
+                   
+                    Seeds
+                   
+                   
+                    
+                     0
+                    
+                    
+                     0
+                    
+                    
+                     
+                      
+                       Qt::Vertical
+                      
+                      
+                       
+                        
+                         0
+                         0
+                        
+                       
+                      
+                      
+                       
+                        
+                         0
+                         0
+                        
+                       
+                      
+                     
+                    
+                   
                   
                  
                 
diff --git a/src/mapview.cpp b/src/mapview.cpp
index 65766bd..11fe039 100644
--- a/src/mapview.cpp
+++ b/src/mapview.cpp
@@ -59,7 +59,7 @@ MapView::MapView(QWidget *parent)
     setFont(fmono);
 
     QPalette pal = palette();
-    pal.setColor(QPalette::Background, Qt::black);
+    pal.setColor(QPalette::Dark, Qt::black);
     setAutoFillBackground(true);
     setPalette(pal);
 
@@ -189,6 +189,13 @@ void MapView::setConfig(const Config& c)
     update(2);
 }
 
+void MapView::setShapes(const std::vector& s)
+{
+    shapes = s;
+    settingsToWorld();
+    update(1);
+}
+
 void MapView::refreshBiomeColors()
 {
     if (world)
@@ -207,6 +214,7 @@ void MapView::settingsToWorld()
     world->memlimit = (uint64_t) config.mapCacheSize * 1024 * 1024;
     world->threadlimit = config.mapThreads;
     world->lopt = lopt;
+    world->shapes = shapes;
 }
 
 static qreal smoothstep(qreal x)
@@ -304,6 +312,27 @@ qreal MapView::getZ()
     return fz;
 }
 
+static qreal clampimax(qreal x, bool *ok = nullptr)
+{
+    const double imax = INT_MAX - 1024.0;
+    if (x < -imax) x = -imax;
+    if (x > +imax) x = +imax;
+    if (ok) *ok = (x > -imax && x < +imax);
+    return x;
+}
+
+void MapView::getVisible(int *x0, int *z0, int *x1, int *z1)
+{
+    qreal x = getX();
+    qreal z = getZ();
+    qreal uiw = width() / blocks2pix;
+    qreal uih = height() / blocks2pix;
+    if (x0) *x0 = (int) clampimax( floor(x - uiw/2) );
+    if (z0) *z0 = (int) clampimax( floor(z - uih/2) );
+    if (x1) *x1 = (int) clampimax( ceil(x + uiw/2) );
+    if (z1) *z1 = (int) clampimax( ceil(z + uih/2) );
+}
+
 void MapView::update(int cnt)
 {
     updatecounter = cnt;
@@ -435,19 +464,12 @@ void MapView::onGoto()
     dialog->show();
 }
 
-static bool clampabs(qreal *x, qreal m)
-{
-    if (*x < -m) { *x = -m; return true; }
-    if (*x > +m) { *x = +m; return true; }
-    return false;
-}
-
 void MapView::paintEvent(QPaintEvent *)
 {
     QPainter painter(this);
 
     painter.setRenderHint(QPainter::Antialiasing);
-    painter.setRenderHint(QPainter::HighQualityAntialiasing);
+    //painter.setRenderHint(QPainter::HighQualityAntialiasing);
 
     qreal fx = getX();
     qreal fz = getZ();
@@ -458,8 +480,11 @@ void MapView::paintEvent(QPaintEvent *)
         focusz = z_dst;
         blocks2pix = 1.0 / s_dst;
     }
-    if (clampabs(&fx, INT_MAX-1024)) focusx = fx;
-    if (clampabs(&fz, INT_MAX-1024)) focusz = fz;
+    bool ok;
+    fx = clampimax(fx, &ok);
+    if (!ok) focusx = fx;
+    fz = clampimax(fz, &ok);
+    if (!ok) focusz = fz;
 
     if (world)
     {
@@ -468,9 +493,7 @@ void MapView::paintEvent(QPaintEvent *)
         QPoint cur = mapFromGlobal(QCursor::pos());
         qreal bx = (cur.x() -  width()/2.0) / blocks2pix + fx;
         qreal bz = (cur.y() - height()/2.0) / blocks2pix + fz;
-        clampabs(&bx, INT_MAX-1024);
-        clampabs(&bz, INT_MAX-1024);
-        Pos p = {(int)bx, (int)bz};
+        Pos p = {(int)clampimax(bx), (int)clampimax(bz)};
         overlay->pos = p;
         overlay->bname = world->getBiomeName(p);
 
diff --git a/src/mapview.h b/src/mapview.h
index 1994d3a..c99e025 100644
--- a/src/mapview.h
+++ b/src/mapview.h
@@ -35,6 +35,7 @@ public:
     qreal getX();
     qreal getZ();
     qreal getScale() const { return 1.0 / blocks2pix; }
+    void getVisible(int *x0, int *z0, int *x1, int *z1);
 
     void deleteWorld();
     void refresh();
@@ -53,6 +54,7 @@ public:
     bool getShow(int stype);
     void setShow(int stype, bool v);
     void setConfig(const Config& config);
+    void setShapes(const std::vector& shapes);
     void refreshBiomeColors();
 
     void timeout();
@@ -110,6 +112,8 @@ private:
     bool measure;
     int updatecounter;
 
+    std::vector shapes;
+
     bool sshow[D_STRUCT_NUM];
     LayerOpt lopt;
     Config config;
diff --git a/src/rangeslider.cpp b/src/rangeslider.cpp
index ab5efde..565a394 100644
--- a/src/rangeslider.cpp
+++ b/src/rangeslider.cpp
@@ -207,7 +207,7 @@ LabeledRange::LabeledRange(QWidget *parent, int vmin, int vmax)
     l->addWidget(minlabel);
     l->addWidget(slider);
     l->addWidget(maxlabel);
-    l->setMargin(0);
+    l->setContentsMargins(0, 0, 0, 0);
     setLayout(l);
 
     connect(slider, SIGNAL(valueChanged(int)), this, SLOT(rangeChanged(void)));
diff --git a/src/scripts.cpp b/src/scripts.cpp
index a77b703..d374a49 100644
--- a/src/scripts.cpp
+++ b/src/scripts.cpp
@@ -72,7 +72,7 @@ void getScripts(QMap& scripts)
     QDirIterator it(dir, QDirIterator::NoIteratorFlags);
     while (it.hasNext())
     {
-        QFileInfo f = it.next();
+        QFileInfo f = QFileInfo(it.next());
         if (f.suffix() != "lua")
             continue;
         uint64_t hash = getScriptHash(f);
@@ -436,19 +436,32 @@ BlockRule *LuaHighlighter::nextBlockRule(const QString& text, int *pos, int *nex
 {
     BlockRule *rule = nullptr;
     int min = INT_MAX;
+    int end = 0;
     for (int i = 0, n = blockrules.size(); i < n; i++)
     {
+#if 1
+        QRegularExpressionMatch m = blockrules[i].start.match(text, *pos);
+        if (m.hasMatch() && m.capturedStart() < min)
+        {
+            rule = &blockrules[i];
+            min = m.capturedStart();
+            end = m.capturedEnd();
+        }
+    }
+#else
         int s = blockrules[i].start.indexIn(text, *pos);
         if (s >= 0 && s < min)
         {
             rule = &blockrules[i];
             min = s;
+            end = s + rule->start.matchedLength();
         }
     }
+#endif
     if (rule)
     {
         *pos = min;
-        *next = min + rule->start.matchedLength();
+        *next = end;
     }
     return rule;
 }
@@ -467,6 +480,21 @@ void LuaHighlighter::highlightBlock(const QString& text)
 
     while (rule)
     {
+#if 1
+        QRegularExpressionMatch m = rule->end.match(text, match);
+        if (m.hasMatch())
+        {
+            markFormated(&line, start, line.length() - start, rule->format);
+            break;
+        }
+        else
+        {
+            int end = m.capturedEnd();
+            markFormated(&line, start, end - start, rule->format);
+            start = end;
+            rule = nextBlockRule(line, &start, &match);
+        }
+#else
         int end = rule->end.indexIn(text, match);
         if (end == -1)
         {
@@ -480,6 +508,7 @@ void LuaHighlighter::highlightBlock(const QString& text)
             start = end;
             rule = nextBlockRule(line, &start, &match);
         }
+#endif
     }
     if (rule)
         setCurrentBlockState(rule - &blockrules[0]);
@@ -489,6 +518,14 @@ void LuaHighlighter::highlightBlock(const QString& text)
     for (const Rule &rule : qAsConst(rules))
     {
         const QString *l = rule.overlay ? &text : &line;
+#if 1
+        QRegularExpressionMatch m = rule.pattern.match(*l);
+        while (m.hasMatch())
+        {
+            setFormat(m.capturedStart(), m.capturedLength(), rule.format);
+            m = rule.pattern.match(*l, m.capturedEnd());
+        }
+#else
         QRegExp expression(rule.pattern);
         int index = expression.indexIn(*l);
         while (index >= 0)
@@ -497,6 +534,7 @@ void LuaHighlighter::highlightBlock(const QString& text)
             setFormat(index, length, rule.format);
             index = expression.indexIn(*l, index + length);
         }
+#endif
     }
 }
 
@@ -633,7 +671,7 @@ void ScriptEditor::keyPressEvent(QKeyEvent *event)
         {
             const QString text = document()->toPlainText();
             const QChar linebreak = QChar(0x2029);
-            QString ws = linebreak + QStringRef(&text, start, end-start).toString();
+            QString ws = linebreak + text.mid(start, end-start);
             cursor.beginEditBlock();
             cursor.insertText(ws);
             cursor.endEditBlock();
diff --git a/src/scripts.h b/src/scripts.h
index 7d320b5..46b5e38 100644
--- a/src/scripts.h
+++ b/src/scripts.h
@@ -8,6 +8,7 @@
 #include 
 #include 
 #include 
+#include 
 
 #include "cubiomes/finders.h"
 
@@ -60,7 +61,7 @@ int runCheckScript(
 
 struct Rule
 {
-    QRegExp pattern;
+    QRegularExpression pattern;
     QTextCharFormat format;
     bool overlay;
     Rule() : pattern(),format(),overlay() {}
@@ -69,7 +70,7 @@ struct Rule
 };
 struct BlockRule
 {
-    QRegExp start, end;
+    QRegularExpression start, end;
     QTextCharFormat format;
     BlockRule() : start(), end(), format() {}
     BlockRule(const QString& s, const QString& e, const QTextCharFormat& f)
diff --git a/src/search.cpp b/src/search.cpp
index 4d18c8c..273fea6 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -34,7 +34,7 @@ QString Condition::summary(bool aligntab) const
     }
 
     QString cnts;
-    if (ft.count)
+    if (ft.branch == FilterInfo::BR_CLUST)
         cnts += MULTIPLY_CHAR + QString::number(count);
     if (skipref)
         cnts += "*";
@@ -73,10 +73,10 @@ QString Condition::summary(bool aligntab) const
     }
     else
     {
-        if (ft.coord)
-            s += QString::asprintf("(%d,%d)", x1*ft.step, z1*ft.step);
-        if (ft.area)
-            s += QString::asprintf(",(%d,%d)", (x2+1)*ft.step-1, (z2+1)*ft.step-1);
+        if (ft.loc & FilterInfo::LOC_1)
+            s += QString::asprintf("(%d,%d)", x1, z1);
+        if (ft.loc & FilterInfo::LOC_2)
+            s += QString::asprintf(",(%d,%d)", x2, z2);
     }
     return s;
 }
@@ -95,15 +95,13 @@ bool Condition::versionUpgrade()
         memset(pad1, 0, sizeof(pad1));
         hash = 0;
         memset(deps, 0, sizeof(deps));
-        memset(pad2, 0, sizeof(pad2));
-        biomeId = biomeSize = tol = minmax = para = octave = 0;
-        varflags = varbiome = varstart = 0;
+        biomeId = biomeSize = tol = minmax = para = octave = step = 0;
     }
-    else if (version == VER_2_3_0)
+    if (version < VER_2_4_0)
     {
         varflags = varbiome = varstart = 0;
     }
-    else if (version == VER_2_4_0)
+    if (version < VER_3_4_0)
     {
         if (type == F_CLIMATE_MINMAX)
         {
@@ -126,6 +124,28 @@ bool Condition::versionUpgrade()
             }
         }
     }
+    if (version < VER_4_0_0)
+    {
+        const FilterInfo& ft = g_filterinfo.list[type];
+        if (ft.grid > 1)
+        {
+            x1 = x1 * ft.grid;
+            z1 = z1 * ft.grid;
+            x2 = (x2+1) * ft.grid - 1;
+            z2 = (z2+1) * ft.grid - 1;
+        }
+        switch (type)
+        {
+        case F_SPIRAL:      step = 1;    break;
+        case F_SPIRAL_4:    step = 4;    type = F_SPIRAL; break;
+        case F_SPIRAL_16:   step = 16;   type = F_SPIRAL; break;
+        case F_SPIRAL_64:   step = 64;   type = F_SPIRAL; break;
+        case F_SPIRAL_256:  step = 256;  type = F_SPIRAL; break;
+        case F_SPIRAL_512:  step = 512;  type = F_SPIRAL; break;
+        case F_SPIRAL_1024: step = 1024; type = F_SPIRAL; break;
+        }
+    }
+
     version = VER_CURRENT;
     return true;
 }
@@ -312,66 +332,96 @@ int testTreeAt(
     ConditionTree *tree = env->condtree;
     Condition& c = tree->condvec[node];
     const std::vector& branches = tree->references[c.save];
-    int st;
+    int st, br;
     int rx1, rz1, rx2, rz2;
-    int sref;
     Pos pos;
     Pos inst[MAX_INSTANCES];
-    const FilterInfo *finfo;
 
     switch (c.type)
     {
-    case F_SPIRAL_1:     sref = 0;  goto L_ref_pow2;
-    case F_SPIRAL_4:     sref = 2;  goto L_ref_pow2;
-    case F_SPIRAL_16:    sref = 4;  goto L_ref_pow2;
-    case F_SPIRAL_64:    sref = 6;  goto L_ref_pow2;
-    case F_SPIRAL_256:   sref = 8;  goto L_ref_pow2;
-    case F_SPIRAL_512:   sref = 9;  goto L_ref_pow2;
-    case F_SPIRAL_1024:  sref = 10; goto L_ref_pow2;
-    L_ref_pow2:
-        rx1 = ((c.x1 << sref) + at.x) >> sref;
-        rz1 = ((c.z1 << sref) + at.z) >> sref;
-        rx2 = ((c.x2 << sref) + at.x) >> sref;
-        rz2 = ((c.z2 << sref) + at.z) >> sref;
+    case F_SPIRAL:
+
         st = COND_FAILED;
         {   // run a spiral iterator over the rectangle
-            int x = (rx1 + rx2) >> 1;
-            int z = (rz1 + rz2) >> 1;
+            int step = c.step ? c.step : 512;
+            int rmax, x1, z1, x2, z2;
+            if (c.rmax > 0)
+            {
+                rmax = c.rmax - 1;
+                x1 = at.x - rmax;
+                z1 = at.z - rmax;
+                x2 = at.x + rmax;
+                z2 = at.z + rmax;
+                rmax = rmax * rmax + 1;
+            }
+            else
+            {
+                rmax = 0;
+                x1 = c.x1 + at.x;
+                z1 = c.z1 + at.z;
+                x2 = c.x2 + at.x;
+                z2 = c.z2 + at.z;
+            }
+
+            rx1 = floordiv(x1, step);
+            rz1 = floordiv(z1, step);
+            rx2 = floordiv(x2, step);
+            rz2 = floordiv(z2, step);
+
+            int rx = (rx1 + rx2) >> 1;
+            int rz = (rz1 + rz2) >> 1;
             int i = 0, dl = 1;
             int dx = 1, dz = 0;
             while (true)
             {
-                bool inx = (x >= rx1 && x <= rx2);
-                bool inz = (z >= rz1 && z <= rz2);
+                bool inx = (rx >= rx1 && rx <= rx2);
+                bool inz = (rz >= rz1 && rz <= rz2);
                 if (!inx && !inz)
                     break;
                 if (inx && inz)
                 {
-                    pos.x = (x << sref);
-                    pos.z = (z << sref);
-                    // children are combined via AND
-                    int sta = COND_OK;
-                    for (int b : branches)
+                    pos.x = rx * step;
+                    pos.z = rz * step;
+
+                    bool inr = true;
+                    if (rmax)
                     {
-                        int stb = testTreeAt(pos, env, pass, abort, path, b);
-                        if (*abort)
-                            return COND_FAILED;
-                        if (stb < sta)
-                            sta = stb;
-                        if (sta == COND_FAILED)
-                            break;
+                        int dx = pos.x - at.x;
+                        int dz = pos.z - at.z;
+                        int64_t rsq = dx*(int64_t)dx + dz*(int64_t)dz;
+                        inr = (rsq < rmax);
+                    }
+                    else if (pos.x < x1 || pos.x > x2 || pos.z < z1 || pos.z > z2)
+                    {
+                        inr = false;
+                    }
+
+                    if (inr)
+                    {
+                        // children are combined via AND
+                        int sta = COND_OK;
+                        for (int b : branches)
+                        {
+                            int stb = testTreeAt(pos, env, pass, abort, path, b);
+                            if (*abort)
+                                return COND_FAILED;
+                            if (stb < sta)
+                                sta = stb;
+                            if (sta == COND_FAILED)
+                                break;
+                        }
+                        if (sta == COND_MAYBE_POS_VALID )
+                            sta = COND_MAYBE_POS_INVAL; // position moves => invalidate
+                        if (sta > st)
+                            st = sta;
+                        if (path && st >= COND_MAYBE_POS_VALID)
+                            path[c.save] = pos;
+                        if (st == COND_OK)
+                            return COND_OK;
                     }
-                    if (sta == COND_MAYBE_POS_VALID )
-                        sta = COND_MAYBE_POS_INVAL; // position moves => invalidate
-                    if (sta > st)
-                        st = sta;
-                    if (path && st >= COND_MAYBE_POS_VALID)
-                        path[c.save] = pos;
-                    if (st == COND_OK)
-                        return COND_OK;
                 }
-                x += dx;
-                z += dz;
+                rx += dx;
+                rz += dz;
                 if (++i == dl)
                 {
                     i = 0;
@@ -412,7 +462,7 @@ int testTreeAt(
         return st;
 
 
-    case F_LOGIC_OR:
+    case F_LOGIC_OR: //qDebug() << at.x << at.z; return COND_FAILED;
         if (branches.empty())
         {
             if (path)
@@ -499,18 +549,48 @@ int testTreeAt(
             {
                 if (icnt == 1)
                     path[c.save] = *inst;
+                else if (icnt > 1 && st == COND_OK)
+                    path[c.save] = *inst;
                 else
                     path[c.save].x = path[c.save].z = -1;
             }
             return st;
         }
-        finfo = g_filterinfo.list + c.type;
-        if (c.count == 1 && (finfo->count || finfo->cat == CAT_QUAD))
-        {   // condition has exactly one required instance so we can check each
-            // of the found instances individually, i.e. this branch splits the
-            // instances into independent subbranches (combined via OR)
-            // quad conditions are also processed here since we want to
-            // examine all instances without support for averaging
+
+        br = g_filterinfo.list[c.type].branch;
+
+        if (br == FilterInfo::BR_NONE || (br == FilterInfo::BR_CLUST && c.count != 1))
+        {   // this condition cannot branch, position of multiple instances
+            // will be averaged to a center point
+            if (c.type == 0)
+            {   // this is the root condition
+                st = COND_OK;
+                pos = at;
+            }
+            else
+            {
+                st = testCondAt(at, env, pass, abort, inst, NULL, &c);
+                if (st == COND_FAILED || st == COND_MAYBE_POS_INVAL)
+                    return st;
+                pos = inst[0]; // center point of instances
+            }
+            for (char b : branches)
+            {
+                if (st == COND_FAILED)
+                    break;
+                int sta = testTreeAt(pos, env, pass, abort, path, b);
+                if (*abort)
+                    return COND_FAILED;
+                if (sta < st)
+                    st = sta;
+            }
+            if (path && st >= COND_MAYBE_POS_VALID)
+                path[c.save] = pos;
+            return st;
+        }
+        else
+        {   // check each instance individually, splitting the instances into
+            // independent subbranches that are combined via OR
             int icnt = MAX_INSTANCES;
             st = testCondAt(at, env, pass, abort, inst, &icnt, &c);
             if (st == COND_FAILED || st == COND_MAYBE_POS_INVAL)
@@ -548,35 +628,6 @@ int testTreeAt(
                 path[c.save] = inst[iok];
             return st;
         }
-        else
-        {   // this condition cannot branch, position of multiple instances
-            // will be averaged to a center point
-            if (c.type == 0)
-            {   // this is the root condition
-                st = COND_OK;
-                pos = at;
-            }
-            else
-            {
-                st = testCondAt(at, env, pass, abort, inst, NULL, &c);
-                if (st == COND_FAILED || st == COND_MAYBE_POS_INVAL)
-                    return st;
-                pos = inst[0]; // center point of instances
-            }
-            for (char b : branches)
-            {
-                if (st == COND_FAILED)
-                    break;
-                int sta = testTreeAt(pos, env, pass, abort, path, b);
-                if (*abort)
-                    return COND_FAILED;
-                if (sta < st)
-                    st = sta;
-            }
-            if (path && st >= COND_MAYBE_POS_VALID)
-                path[c.save] = pos;
-            return st;
-        }
     }
 }
 
@@ -895,6 +946,59 @@ static int f_track_minmax(void *data, int x, int z, double p)
     return 0;
 }
 
+
+struct sample_boime_t
+{
+    Condition *cond;
+    Pos at;
+    int rmaxsq;
+    int n;
+    int64_t xsum;
+    int64_t zsum;
+    Pos *cent;
+    int *imax;
+    std::atomic_bool *stop;
+};
+
+static int f_biome_sampler(Generator *g, int scale, int x, int y, int z, void *data)
+{
+    sample_boime_t *info = (sample_boime_t*) data;
+    if (info->stop && *info->stop)
+        return -2;
+    if (info->rmaxsq)
+    {
+        int dx = x - info->at.x;
+        int dz = z - info->at.z;
+        int64_t rsq = dx*(int64_t)dx + dz*(int64_t)dz;
+        if (rsq >= info->rmaxsq)
+            return -1;
+    }
+
+    int id = getBiomeAt(g, scale, x, y, z);
+    uint64_t incl = 0, excl = 0;
+    if (id < 128) {
+        incl = info->cond->biomeToFind & (1ULL << id);
+        excl = info->cond->biomeToExcl & (1ULL << id);
+    } else {
+        incl = info->cond->biomeToFindM & (1ULL << (id-128));
+        excl = info->cond->biomeToExclM & (1ULL << (id-128));
+    }
+    if (incl != 0)
+    {
+        if (info->imax && info->n < *info->imax)
+            info->cent[info->n] = Pos{x, z};
+        info->xsum += x;
+        info->zsum += z;
+        info->n++;
+        return 1;
+    }
+    if (excl != 0)
+    {
+        return 0;
+    }
+    return 0;
+}
+
 /* Tests if a condition is satisfied with 'at' as origin for a search pass.
  * If sufficiently satisfied (check return value) then:
  * when 'imax' is NULL, the center position is written to 'cent[0]'
@@ -933,9 +1037,26 @@ testCondAt(
             return COND_FAILED;
     }
 
+    if (cond->rmax > 0)
+    {
+        rmax = cond->rmax - 1;
+        x1 = at.x - rmax;
+        z1 = at.z - rmax;
+        x2 = at.x + rmax;
+        z2 = at.z + rmax;
+    }
+    else
+    {
+        rmax = 0;
+        x1 = cond->x1 + at.x;
+        z1 = cond->z1 + at.z;
+        x2 = cond->x2 + at.x;
+        z2 = cond->z2 + at.z;
+    }
+
     switch (cond->type)
     {
-    case F_SPIRAL_1:
+    case F_SPIRAL:
     case F_SPIRAL_4:
     case F_SPIRAL_16:
     case F_SPIRAL_64:
@@ -968,10 +1089,10 @@ testCondAt(
         n = sizeof(low20QuadHutBarely) / sizeof(uint64_t);
 
 L_qh_any:
-        rx1 = ((cond->x1 << 9) + at.x) >> 9;
-        rz1 = ((cond->z1 << 9) + at.z) >> 9;
-        rx2 = ((cond->x2 << 9) + at.x) >> 9;
-        rz2 = ((cond->z2 << 9) + at.z) >> 9;
+        rx1 = x1 >> 9;
+        rz1 = z1 >> 9;
+        rx2 = x2 >> 9;
+        rz2 = z2 >> 9;
 
         n = scanForQuads(
                 sconf, 128, (env->seed) & MASK48, seeds, n, 20, sconf.salt,
@@ -1009,10 +1130,10 @@ L_qh_any:
     case F_QM_90:   qual = 58*58*4 * 90 / 100;
 L_qm_any:
 
-        rx1 = ((cond->x1 << 9) + at.x) >> 9;
-        rz1 = ((cond->z1 << 9) + at.z) >> 9;
-        rx2 = ((cond->x2 << 9) + at.x) >> 9;
-        rz2 = ((cond->z2 << 9) + at.z) >> 9;
+        rx1 = x1 >> 9;
+        rz1 = z1 >> 9;
+        rx2 = x2 >> 9;
+        rz2 = z2 >> 9;
         // we don't really need to check for more than one instance here
         n = scanForQuads(
                 sconf, 160, (env->seed) & MASK48, g_qm_90,
@@ -1068,23 +1189,6 @@ L_qm_any:
     case F_ENDCITY:
     case F_GATEWAY:
 
-        if (cond->rmax > 0)
-        {
-            rmax = (cond->rmax-1) * (cond->rmax-1) + 1;
-            x1 = at.x - cond->rmax;
-            z1 = at.z - cond->rmax;
-            x2 = at.x + cond->rmax;
-            z2 = at.z + cond->rmax;
-        }
-        else
-        {
-            rmax = 0;
-            x1 = cond->x1 + at.x;
-            z1 = cond->z1 + at.z;
-            x2 = cond->x2 + at.x;
-            z2 = cond->z2 + at.z;
-        }
-
         if (sconf.regionSize == 32)
         {
             rx1 = x1 >> 9;
@@ -1239,41 +1343,12 @@ L_qm_any:
 
     case F_MINESHAFT:
 
-        if (cond->rmax > 0)
-        {
-            rmax = (cond->rmax-1) * (cond->rmax-1) + 1;
-            x1 = at.x - cond->rmax;
-            z1 = at.z - cond->rmax;
-            x2 = at.x + cond->rmax;
-            z2 = at.z + cond->rmax;
-        }
-        else
-        {
-            rmax = 0;
-            x1 = cond->x1 + at.x;
-            z1 = cond->z1 + at.z;
-            x2 = cond->x2 + at.x;
-            z2 = cond->z2 + at.z;
-        }
         rx1 = x1 >> 4;
         rz1 = z1 >> 4;
         rx2 = x2 >> 4;
         rz2 = z2 >> 4;
 
-        if (cond->count <= 0)
-        {   // exclusion
-            icnt = getMineshafts(env->mc, env->seed, rx1, rz1, rx2, rz2, cent, 1);
-            if (icnt == 1 && cond->skipref && cent->x == at.x && cent->z == at.z)
-                icnt = 0;
-            cent->x = (x1 + x2) >> 1;
-            cent->z = (z1 + z2) >> 1;
-            if (icnt == 0)
-            {
-                if (imax) *imax = 1;
-                return COND_OK;
-            }
-        }
-        else if (imax)
+        if (imax && cond->count > 0)
         {   // just check there are at least *inst (== cond->count) instances
             *imax = icnt =
                 getMineshafts(env->mc, env->seed, rx1, rz1, rx2, rz2, cent, *imax);
@@ -1328,7 +1403,17 @@ L_qm_any:
                 zt += p[i].z;
                 j++;
             }
-            if (j >= cond->count)
+            if (cond->count <= 0)
+            {
+                cent->x = (x1 + x2) >> 1;
+                cent->z = (z1 + z2) >> 1;
+                if (j == 0)
+                {
+                    if (imax) *imax = 1;
+                    return COND_OK;
+                }
+            }
+            else if (j >= cond->count)
             {
                 cent->x = xt / j;
                 cent->z = zt / j;
@@ -1344,22 +1429,6 @@ L_qm_any:
         if (pass != PASS_FULL_64)
             return COND_MAYBE_POS_INVAL;
 
-        if (cond->rmax > 0)
-        {
-            rmax = (cond->rmax-1) * (cond->rmax-1) + 1;
-            x1 = at.x - cond->rmax;
-            z1 = at.z - cond->rmax;
-            x2 = at.x + cond->rmax;
-            z2 = at.z + cond->rmax;
-        }
-        else
-        {
-            rmax = 0;
-            x1 = cond->x1 + at.x;
-            z1 = cond->z1 + at.z;
-            x2 = cond->x2 + at.x;
-            z2 = cond->z2 + at.z;
-        }
         if (*abort) return COND_FAILED;
         env->init4Dim(DIM_OVERWORLD);
         pc = getSpawn(&env->g);
@@ -1398,10 +1467,6 @@ L_qm_any:
         }
         else
         {
-            x1 = cond->x1 + at.x;
-            z1 = cond->z1 + at.z;
-            x2 = cond->x2 + at.x;
-            z2 = cond->z2 + at.z;
             if (pc.x < x1 || pc.x > x2 || pc.z < z1 || pc.z > z2)
                 return COND_FAILED;
         }
@@ -1564,10 +1629,10 @@ L_qm_any:
 
     case F_SLIME:
 
-        rx1 = ((cond->x1 << 4) + at.x) >> 4;
-        rz1 = ((cond->z1 << 4) + at.z) >> 4;
-        rx2 = ((cond->x2 << 4) + at.x) >> 4;
-        rz2 = ((cond->z2 << 4) + at.z) >> 4;
+        rx1 = x1 >> 4;
+        rz1 = z1 >> 4;
+        rx2 = x2 >> 4;
+        rz2 = z2 >> 4;
 
         icnt = 0;
         xt = zt = 0;
@@ -1602,8 +1667,8 @@ L_qm_any:
         }
         if (cond->count == 0)
         {   // exclusion filter
-            cent->x = (rx1 + rx2) << 3;
-            cent->z = (rz1 + rz2) << 3;
+            cent->x = (x1 + x2) >> 1;
+            cent->z = (z1 + z2) >> 1;
             if (imax) *imax = 1;
             return COND_OK;
         }
@@ -1613,13 +1678,65 @@ L_qm_any:
         }
         else if (icnt)
         {
-            cent->x = (xt << 4) / icnt;
-            cent->z = (zt << 4) / icnt;
+            cent->x = (xt << 4) / icnt + 8;
+            cent->z = (zt << 4) / icnt + 8;
         }
         if (icnt >= cond->count)
             return COND_OK;
         return COND_FAILED;
 
+
+    case F_BIOME_SAMPLE:
+
+        if (pass != PASS_FULL_64)
+            return COND_MAYBE_POS_INVAL;
+        if (cond->confidence <= 0 || cond->confidence >= 1)
+            return COND_FAILED;
+        if (cond->converage <= 0 || cond->converage > 1)
+            return COND_FAILED;
+        s = finfo.pow2;
+        rx1 = x1 >> s;
+        rz1 = z1 >> s;
+        rx2 = x2 >> s;
+        rz2 = z2 >> s;
+        {
+            int w = rx2 - rx1 + 1;
+            int h = rz2 - rz1 + 1;
+            Range r = {1<y : cond->y >> 2, 1};
+            env->init4Dim(DIM_OVERWORLD);
+            sample_boime_t sample;
+            sample.cond = cond;
+            sample.at = at;
+            sample.n = 0;
+            sample.xsum = 0;
+            sample.zsum = 0;
+            sample.imax = imax;
+            sample.cent = cent;
+            sample.stop = abort;
+
+            uint64_t rng;
+            setSeed(&rng, env->seed);
+
+            int ok = monteCarloBiomes(
+                        &env->g, r, &rng, cond->converage, cond->confidence,
+                        &f_biome_sampler, &sample);
+            if (imax)
+            {
+                *imax = sample.n;
+            }
+            else if (sample.n)
+            {
+                cent->x = sample.xsum / sample.n + 2;
+                cent->z = sample.zsum / sample.n + 2;
+            }
+            else
+            {
+                *cent = at;
+            }
+            return ok == 1 ? COND_OK : COND_FAILED;
+        }
+        return COND_FAILED;
+
     // biome filters reference specific layers
     // MAYBE: options for layers in different versions?
     case F_BIOME:
@@ -1632,12 +1749,12 @@ L_qm_any:
         if (env->mc >= MC_1_18)
             return COND_FAILED;
         s = finfo.pow2;
-        rx1 = ((cond->x1 << s) + at.x) >> s;
-        rz1 = ((cond->z1 << s) + at.z) >> s;
-        rx2 = ((cond->x2 << s) + at.x) >> s;
-        rz2 = ((cond->z2 << s) + at.z) >> s;
-        cent->x = ((rx1 + rx2) << s) >> 1;
-        cent->z = ((rz1 + rz2) << s) >> 1;
+        rx1 = x1 >> s;
+        rz1 = z1 >> s;
+        rx2 = x2 >> s;
+        rz2 = z2 >> s;
+        cent->x = (x1 + x2) >> 1;
+        cent->z = (z1 + z2) >> 1;
         if (pass == PASS_FAST_48)
             return COND_MAYBE_POS_VALID;
         if (pass == PASS_FULL_48)
@@ -1663,12 +1780,12 @@ L_qm_any:
     case F_TEMPS:
         if (env->mc >= MC_1_18)
             return COND_FAILED;
-        rx1 = ((cond->x1 << 10) + at.x) >> 10;
-        rz1 = ((cond->z1 << 10) + at.z) >> 10;
-        rx2 = ((cond->x2 << 10) + at.x) >> 10;
-        rz2 = ((cond->z2 << 10) + at.z) >> 10;
-        cent->x = ((rx1 + rx2) << 10) >> 1;
-        cent->z = ((rz1 + rz2) << 10) >> 1;
+        rx1 = x1 >> 10;
+        rz1 = z1 >> 10;
+        rx2 = x2 >> 10;
+        rz2 = z2 >> 10;
+        cent->x = (x1 + x2) >> 1;
+        cent->z = (z1 + z2) >> 1;
         if (pass != PASS_FULL_64)
             return COND_MAYBE_POS_VALID;
         env->init4Dim(DIM_OVERWORLD);
@@ -1692,12 +1809,12 @@ L_qm_any:
 
 L_noise_biome:
         s = finfo.pow2;
-        rx1 = ((cond->x1 << s) + at.x) >> s;
-        rz1 = ((cond->z1 << s) + at.z) >> s;
-        rx2 = ((cond->x2 << s) + at.x) >> s;
-        rz2 = ((cond->z2 << s) + at.z) >> s;
-        cent->x = ((rx1 + rx2) << s) >> 1;
-        cent->z = ((rz1 + rz2) << s) >> 1;
+        rx1 = x1 >> s;
+        rz1 = z1 >> s;
+        rx2 = x2 >> s;
+        rz2 = z2 >> s;
+        cent->x = (x1 + x2) >> 1;
+        cent->z = (z1 + z2) >> 1;
         if (pass == PASS_FAST_48)
             return COND_MAYBE_POS_VALID;
         // the Nether and End require only the 48-bit seed
@@ -1720,13 +1837,13 @@ L_noise_biome:
         if (pass == PASS_FULL_64)
         {
             s = finfo.pow2;
-            rx1 = ((cond->x1 << s) + at.x) >> s;
-            rz1 = ((cond->z1 << s) + at.z) >> s;
-            rx2 = ((cond->x2 << s) + at.x) >> s;
-            rz2 = ((cond->z2 << s) + at.z) >> s;
+            rx1 = x1 >> s;
+            rz1 = z1 >> s;
+            rx2 = x2 >> s;
+            rz2 = z2 >> s;
             int w = rx2 - rx1 + 1;
             int h = rz2 - rz1 + 1;
-            Range r = {finfo.step, rx1, rz1, w, h, cond->y >> 2, 1};
+            Range r = {1<y >> 2, 1};
             env->init4Dim(DIM_OVERWORLD);
 
             if (cond->count == 0)
@@ -1737,8 +1854,8 @@ L_noise_biome:
                 );
                 if (icnt == 0)
                 {
-                    cent->x = (rx1 + rx2) << 1;
-                    cent->z = (rz1 + rz2) << 1;
+                    cent->x = (x1 + x2) >> 1;
+                    cent->z = (z1 + z2) >> 1;
                     if (imax) *imax = 1;
                     return COND_OK;
                 }
@@ -1782,8 +1899,8 @@ L_noise_biome:
                 }
                 if (j >= cond->count)
                 {
-                    cent->x = xt / j;
-                    cent->z = zt / j;
+                    cent->x = xt / j + (1 << s) / 2;
+                    cent->z = zt / j + (1 << s) / 2;
                     return COND_OK;
                 }
             }
@@ -1794,10 +1911,10 @@ L_noise_biome:
     case F_CLIMATE_MINMAX:
         if (env->mc < MC_1_18 || cond->para >= NP_MAX)
             return COND_FAILED;
-        rx1 = ((cond->x1 << 2) + at.x) >> 2;
-        rz1 = ((cond->z1 << 2) + at.z) >> 2;
-        rx2 = ((cond->x2 << 2) + at.x) >> 2;
-        rz2 = ((cond->z2 << 2) + at.z) >> 2;
+        rx1 = x1 >> 2;
+        rz1 = z1 >> 2;
+        rx2 = x2 >> 2;
+        rz2 = z2 >> 2;
         if (pass != PASS_FULL_64)
             return COND_MAYBE_POS_INVAL;
         {
@@ -1836,12 +1953,12 @@ L_noise_biome:
     case F_CLIMATE_NOISE:
         if (env->mc < MC_1_18)
             return COND_FAILED;
-        rx1 = ((cond->x1 << 2) + at.x) >> 2;
-        rz1 = ((cond->z1 << 2) + at.z) >> 2;
-        rx2 = ((cond->x2 << 2) + at.x) >> 2;
-        rz2 = ((cond->z2 << 2) + at.z) >> 2;
-        cent->x = ((rx1 + rx2) << 2) >> 1;
-        cent->z = ((rz1 + rz2) << 2) >> 1;
+        rx1 = x1 >> 2;
+        rz1 = z1 >> 2;
+        rx2 = x2 >> 2;
+        rz2 = z2 >> 2;
+        cent->x = (x1 + x2) >> 1;
+        cent->z = (z1 + z2) >> 1;
         if (pass != PASS_FULL_64)
             return COND_MAYBE_POS_VALID;
         {
@@ -1897,10 +2014,10 @@ L_noise_biome:
 
 
     case F_HEIGHT:
-        rx1 = ((cond->x1 << 2) + at.x) >> 2;
-        rz1 = ((cond->z1 << 2) + at.z) >> 2;
-        cent->x = rx1 << 2;
-        cent->z = rz1 << 2;
+        rx1 = x1 >> 2;
+        rz1 = z1 >> 2;
+        cent->x = x1;
+        cent->z = z1;
         if (pass != PASS_FULL_64)
             return COND_MAYBE_POS_VALID;
         env->init4Dim(DIM_OVERWORLD);
@@ -2015,3 +2132,4 @@ void findQuadStructs(int styp, Generator *g, QVector *out)
 
 
 
+
diff --git a/src/search.h b/src/search.h
index 344fda5..26f12bf 100644
--- a/src/search.h
+++ b/src/search.h
@@ -69,7 +69,7 @@ enum
     F_PORTALN,
     F_GATEWAY,
     F_MINESHAFT,
-    F_SPIRAL_1,
+    F_SPIRAL,
     F_SPIRAL_16,
     F_SPIRAL_64,
     F_SPIRAL_256,
@@ -91,22 +91,35 @@ enum
     F_LUA,
     F_WELL,
     F_TRAILS,
+    F_BIOME_SAMPLE,
     // new filters should be added here at the end to keep some downwards compatibility
     FILTER_MAX,
 };
 
 struct FilterInfo
 {
+    enum {
+        LOC_1 = 1, LOC_2 = 2, LOC_R = 4,
+        LOC_NIL = 0x0,
+        LOC_POS = 0x1,
+        LOC_REC = 0x3,
+        LOC_RAD = 0x7,
+    };
+    enum {
+        BR_NONE  = 0, // one position - no branching
+        BR_FIRST = 1, // choose only first, no branching
+        BR_SPLIT = 2, // branches are examined separately
+        BR_CLUST = 3, // allow clustering to avoid branching
+    };
+
     int cat;    // seed source category
     bool dep64; // depends on 64-bit seed
-    bool coord; // requires coordinate entry
-    bool area;  // requires area entry
-    bool rmax;  // supports radial range
+    int loc;
     int layer;  // associated generator layer
     int stype;  // structure type
-    int step;   // coordinate multiplier
-    int pow2;   // bit position of step
-    int count;  // can have instances
+    int grid;   // coordinate multiplier
+    int pow2;   // bit position of grid
+    int branch; // branching behaviour
     int mcmin;  // minimum version
     int mcmax;  // maximum version
     int dim;    // dimension
@@ -118,7 +131,7 @@ struct FilterInfo
 };
 
 // global table of filter data (as constants with enum indexing)
-static const struct FilterList
+static const struct FilterList : private FilterInfo
 {
     FilterInfo list[FILTER_MAX];
 
@@ -127,13 +140,13 @@ static const struct FilterList
         int disp = 0; // display order
 
         list[F_SELECT] = FilterInfo{
-            CAT_NONE, 0, 0, 0, 0, 0, 0, 0, 0, 0, MC_UNDEF, MC_NEWEST, 0, 0, disp++,
+            CAT_NONE, 0, LOC_NIL, 0, 0, 0, 0, BR_NONE, MC_UNDEF, MC_NEWEST, 0, 0, disp++,
             NULL,
             "",
             ""
         };
         list[F_LOGIC_OR] = FilterInfo{
-            CAT_HELPER, 0, 0, 0, 0, 0, 0, 1, 0, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
+            CAT_HELPER, 0, LOC_NIL, 0, 0, 1, 0, BR_NONE, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
             "helper",
             QT_TRANSLATE_NOOP("Filter", "OR logic gate"),
             QT_TRANSLATE_NOOP("Filter",
@@ -142,7 +155,7 @@ static const struct FilterList
             "defined, it defaults to true.")
         };
         list[F_LOGIC_NOT] = FilterInfo{
-            CAT_HELPER, 0, 0, 0, 0, 0, 0, 1, 0, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
+            CAT_HELPER, 0, LOC_NIL, 0, 0, 1, 0, BR_NONE, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
             "helper",
             QT_TRANSLATE_NOOP("Filter", "NOT logic gate"),
             QT_TRANSLATE_NOOP("Filter",
@@ -151,79 +164,41 @@ static const struct FilterList
             "defined, it defaults to true.")
         };
         list[F_LUA] = FilterInfo{
-            CAT_HELPER, 0, 0, 0, 0, 0, 0, 1, 0, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
+            CAT_HELPER, 0, LOC_NIL, 0, 0, 1, 0, BR_NONE, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
             "helper",
             QT_TRANSLATE_NOOP("Filter", "Lua"),
             QT_TRANSLATE_NOOP("Filter",
             "Define custom conditions using Lua scripts.")
         };
         list[F_SCALE_TO_NETHER] = FilterInfo{
-            CAT_HELPER, 0, 0, 0, 0, 0, 0, 1, 0, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
+            CAT_HELPER, 0, LOC_NIL, 0, 0, 1, 0, BR_NONE, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
             "portal_lit",
             QT_TRANSLATE_NOOP("Filter", "Coordinate factor x/8"),
             QT_TRANSLATE_NOOP("Filter",
             "Divides relative location by 8, from Overworld to Nether.")
         };
         list[F_SCALE_TO_OVERWORLD] = FilterInfo{
-            CAT_HELPER, 0, 0, 0, 0, 0, 0, 1, 0, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
+            CAT_HELPER, 0, LOC_NIL, 0, 0, 1, 0, BR_NONE, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
             "portal_lit",
             QT_TRANSLATE_NOOP("Filter", "Coordinate factor x*8"),
             QT_TRANSLATE_NOOP("Filter",
             "Multiplies relative location by 8, from Nether to Overworld.")
         };
-        const char *spiral_desc = QT_TRANSLATE_NOOP("Filter",
+        list[F_SPIRAL] = FilterInfo{
+            CAT_HELPER, 0, LOC_RAD, 0, 0, 1, 0, BR_FIRST, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
+            "reference",
+            QT_TRANSLATE_NOOP("Filter", "Spiral iterator"),
+            QT_TRANSLATE_NOOP("Filter",
             ""
             "Spiral iterator conditions can be used to move a testing position across "
             "a given area using a certain step size. Other conditions that refer to it "
             "as a relative location will be checked at each step. The iteration is "
             "performed in a spiral, so positions closer to the center get priority."
-            ""
-        );
-        list[F_SPIRAL_1] = FilterInfo{
-            CAT_HELPER, 0, 1, 1, 0, 0, 0, 1, 0, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
-            "reference",
-            QT_TRANSLATE_NOOP("Filter", "Spiral iterator 1:1"),
-            spiral_desc
-        };
-        list[F_SPIRAL_4] = FilterInfo{
-            CAT_HELPER, 0, 1, 1, 0, 0, 0, 4, 2, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
-            "reference",
-            QT_TRANSLATE_NOOP("Filter", "Spiral iterator 1:4"),
-            spiral_desc
-        };
-        list[F_SPIRAL_16] = FilterInfo{
-            CAT_HELPER, 0, 1, 1, 0, 0, 0, 16, 4, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
-            "reference",
-            QT_TRANSLATE_NOOP("Filter", "Spiral iterator 1:16"),
-            spiral_desc
-        };
-        list[F_SPIRAL_64] = FilterInfo{
-            CAT_HELPER, 0, 1, 1, 0, 0, 0, 64, 6, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
-            "reference",
-            QT_TRANSLATE_NOOP("Filter", "Spiral iterator 1:64"),
-            spiral_desc
-        };
-        list[F_SPIRAL_256] = FilterInfo{
-            CAT_HELPER, 0, 1, 1, 0, 0, 0, 256, 8, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
-            "reference",
-            QT_TRANSLATE_NOOP("Filter", "Spiral iterator 1:256"),
-            spiral_desc
-        };
-        list[F_SPIRAL_512] = FilterInfo{
-            CAT_HELPER, 0, 1, 1, 0, 0, 0, 512, 9, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
-            "reference",
-            QT_TRANSLATE_NOOP("Filter", "Spiral iterator 1:512"),
-            spiral_desc
-        };
-        list[F_SPIRAL_1024] = FilterInfo{
-            CAT_HELPER, 0, 1, 1, 0, 0, 0, 1024, 10, 0, MC_UNDEF, MC_NEWEST, DIM_UNDEF, 0, disp++,
-            "reference",
-            QT_TRANSLATE_NOOP("Filter", "Spiral iterator 1:1024"),
-            spiral_desc
+            "")
         };
 
         list[F_QH_IDEAL] = FilterInfo{
-            CAT_QUAD, 0, 1, 1, 0, 0, Swamp_Hut, 512, 9, 0, MC_1_4, MC_NEWEST, 0, 0, disp++,
+            CAT_QUAD, 0, LOC_REC, 0, Swamp_Hut, 512, 9, BR_FIRST, MC_1_4, MC_NEWEST, 0, 0, disp++,
             "quad",
             QT_TRANSLATE_NOOP("Filter", "Quad-hut (ideal)"),
             QT_TRANSLATE_NOOP("Filter",
@@ -232,7 +207,7 @@ static const struct FilterList
         };
 
         list[F_QH_CLASSIC] = FilterInfo{
-            CAT_QUAD, 0, 1, 1, 0, 0, Swamp_Hut, 512, 9, 0, MC_1_4, MC_NEWEST, 0, 0, disp++,
+            CAT_QUAD, 0, LOC_REC, 0, Swamp_Hut, 512, 9, BR_FIRST, MC_1_4, MC_NEWEST, 0, 0, disp++,
             "quad",
             QT_TRANSLATE_NOOP("Filter", "Quad-hut (classic)"),
             QT_TRANSLATE_NOOP("Filter",
@@ -243,7 +218,7 @@ static const struct FilterList
         };
 
         list[F_QH_NORMAL] = FilterInfo{
-            CAT_QUAD, 0, 1, 1, 0, 0, Swamp_Hut, 512, 9, 0, MC_1_4, MC_NEWEST, 0, 0, disp++,
+            CAT_QUAD, 0, LOC_REC, 0, Swamp_Hut, 512, 9, BR_FIRST, MC_1_4, MC_NEWEST, 0, 0, disp++,
             "quad",
             QT_TRANSLATE_NOOP("Filter", "Quad-hut (normal)"),
             QT_TRANSLATE_NOOP("Filter",
@@ -254,7 +229,7 @@ static const struct FilterList
         };
 
         list[F_QH_BARELY] = FilterInfo{
-            CAT_QUAD, 0, 1, 1, 0, 0, Swamp_Hut, 512, 9, 0, MC_1_4, MC_NEWEST, 0, 0, disp++,
+            CAT_QUAD, 0, LOC_REC, 0, Swamp_Hut, 512, 9, BR_FIRST, MC_1_4, MC_NEWEST, 0, 0, disp++,
             "quad",
             QT_TRANSLATE_NOOP("Filter", "Quad-hut (barely)"),
             QT_TRANSLATE_NOOP("Filter",
@@ -264,7 +239,7 @@ static const struct FilterList
         };
 
         list[F_QM_95] = FilterInfo{
-            CAT_QUAD, 0, 1, 1, 0, 0, Monument, 512, 9, 0, MC_1_8, MC_NEWEST, 0, 0, disp++,
+            CAT_QUAD, 0, LOC_REC, 0, Monument, 512, 9, BR_FIRST, MC_1_8, MC_NEWEST, 0, 0, disp++,
             "quad",
             QT_TRANSLATE_NOOP("Filter", "Quad-ocean-monument (>95%)"),
             QT_TRANSLATE_NOOP("Filter",
@@ -274,7 +249,7 @@ static const struct FilterList
         };
 
         list[F_QM_90] = FilterInfo{
-            CAT_QUAD, 0, 1, 1, 0, 0, Monument, 512, 9, 0, MC_1_8, MC_NEWEST, 0, 0, disp++,
+            CAT_QUAD, 0, LOC_REC, 0, Monument, 512, 9, BR_FIRST, MC_1_8, MC_NEWEST, 0, 0, disp++,
             "quad",
             QT_TRANSLATE_NOOP("Filter", "Quad-ocean-monument (>90%)"),
             QT_TRANSLATE_NOOP("Filter",
@@ -283,8 +258,17 @@ static const struct FilterList
             "location.")
         };
 
+        list[F_BIOME_SAMPLE] = FilterInfo{
+            CAT_BIOMES, 1, LOC_RAD, 0, 0, 1, 0, BR_SPLIT, MC_B1_7, MC_NEWEST, 0, 1, disp++,
+            "map",
+            QT_TRANSLATE_NOOP("Filter", "Biome samples"),
+            QT_TRANSLATE_NOOP("Filter",
+            "Samples biomes in a given area to find if a proportion of the "
+            "biomes match a set of allowed biomes.")
+        };
+
         list[F_BIOME] = FilterInfo{
-            CAT_BIOMES, 1, 1, 1, 0, L_VORONOI_1, 0, 1, 0, 0, MC_B1_7, MC_1_17, 0, 1, disp++, // disable for 1.18
+            CAT_BIOMES, 1, LOC_REC, L_VORONOI_1, 0, 1, 0, BR_NONE, MC_B1_7, MC_1_17, 0, 1, disp++, // disable for 1.18
             "map",
             QT_TRANSLATE_NOOP("Filter", "Biomes 1:1"),
             QT_TRANSLATE_NOOP("Filter",
@@ -293,7 +277,7 @@ static const struct FilterList
         };
 
         list[F_BIOME_4] = FilterInfo{
-            CAT_BIOMES, 1, 1, 1, 0, 0, 0, 4, 2, 0, MC_B1_7, MC_NEWEST, 0, 1, disp++,
+            CAT_BIOMES, 1, LOC_REC, 0, 0, 4, 2, BR_NONE, MC_B1_7, MC_NEWEST, 0, 1, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Biomes 1:4"),
             QT_TRANSLATE_NOOP("Filter",
@@ -301,7 +285,7 @@ static const struct FilterList
             "discard those that have biomes that are explicitly excluded (-).")
         };
         list[F_BIOME_16] = FilterInfo{
-            CAT_BIOMES, 1, 1, 1, 0, 0, 0, 16, 4, 0, MC_B1_7, MC_NEWEST, 0, 1, disp++,
+            CAT_BIOMES, 1, LOC_REC, 0, 0, 16, 4, BR_NONE, MC_B1_7, MC_NEWEST, 0, 1, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Biomes 1:16"),
             QT_TRANSLATE_NOOP("Filter",
@@ -309,7 +293,7 @@ static const struct FilterList
             "discard those that have biomes that are explicitly excluded (-).")
         };
         list[F_BIOME_64] = FilterInfo{
-            CAT_BIOMES, 1, 1, 1, 0, 0, 0, 64, 6, 0, MC_B1_7, MC_NEWEST, 0, 1, disp++,
+            CAT_BIOMES, 1, LOC_REC, 0, 0, 64, 6, BR_NONE, MC_B1_7, MC_NEWEST, 0, 1, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Biomes 1:64"),
             QT_TRANSLATE_NOOP("Filter",
@@ -317,7 +301,7 @@ static const struct FilterList
             "discard those that have biomes that are explicitly excluded (-).")
         };
         list[F_BIOME_256] = FilterInfo{
-            CAT_BIOMES, 1, 1, 1, 0, 0, 0, 256, 8, 0, MC_B1_7, MC_NEWEST, 0, 1, disp++,
+            CAT_BIOMES, 1, LOC_REC, 0, 0, 256, 8, BR_NONE, MC_B1_7, MC_NEWEST, 0, 1, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Biomes 1:256"),
             QT_TRANSLATE_NOOP("Filter",
@@ -326,7 +310,7 @@ static const struct FilterList
         };
 
         list[F_BIOME_4_RIVER] = FilterInfo{
-            CAT_BIOMES, 1, 1, 1, 0, L_RIVER_MIX_4, 0, 4, 2, 0, MC_1_13, MC_1_17, 0, 0, disp++,
+            CAT_BIOMES, 1, LOC_REC, L_RIVER_MIX_4, 0, 4, 2, BR_NONE, MC_1_13, MC_1_17, 0, 0, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Biomes 1:4 RIVER"),
             QT_TRANSLATE_NOOP("Filter",
@@ -336,7 +320,7 @@ static const struct FilterList
             "This layer does not generate ocean variants.")
         };
         list[F_BIOME_256_OTEMP] = FilterInfo{
-            CAT_BIOMES, 0, 1, 1, 0, L_OCEAN_TEMP_256, 0, 256, 8, 0, MC_1_13, MC_1_17, 0, 0, disp++,
+            CAT_BIOMES, 0, LOC_REC, L_OCEAN_TEMP_256, 0, 256, 8, BR_NONE, MC_1_13, MC_1_17, 0, 0, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Biomes 1:256 O.TEMP"),
             QT_TRANSLATE_NOOP("Filter",
@@ -346,7 +330,7 @@ static const struct FilterList
             "This generation layer depends only on the lower 48-bits of the seed.")
         };
         list[F_CLIMATE_NOISE] = FilterInfo{
-            CAT_BIOMES, 0, 1, 1, 0, 0, 0, 4, 2, 0, MC_1_18, MC_NEWEST, 0, 0, disp++,
+            CAT_BIOMES, 0, LOC_REC, 0, 0, 4, 2, BR_NONE, MC_1_18, MC_NEWEST, 0, 0, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Climate parameters 1:4"),
             QT_TRANSLATE_NOOP("Filter",
@@ -354,28 +338,28 @@ static const struct FilterList
             "the specified area should cover.")
         };
         list[F_CLIMATE_MINMAX] = FilterInfo{
-            CAT_BIOMES, 0, 1, 1, 0, 0, 0, 4, 2, 0, MC_1_18, MC_NEWEST, 0, 0, disp++,
+            CAT_BIOMES, 0, LOC_REC, 0, 0, 4, 2, BR_NONE, MC_1_18, MC_NEWEST, 0, 0, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Locate climate extreme 1:4"),
             QT_TRANSLATE_NOOP("Filter",
             "Finds the location where a climate parameter reaches its minimum or maximum.")
         };
         list[F_BIOME_CENTER] = FilterInfo{
-            CAT_BIOMES, 1, 1, 1, 0, 0, 0, 4, 2, 1, MC_B1_7, MC_NEWEST, 0, 1, disp++,
+            CAT_BIOMES, 1, LOC_REC, 0, 0, 4, 2, BR_CLUST, MC_B1_7, MC_NEWEST, 0, 1, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Locate biome center 1:4"),
             QT_TRANSLATE_NOOP("Filter",
             "Finds the center position of a given biome.")
         };
         list[F_BIOME_CENTER_256] = FilterInfo{
-            CAT_BIOMES, 1, 1, 1, 0, 0, 0, 256, 8, 1, MC_B1_7, MC_1_17, 0, 1, disp++,
+            CAT_BIOMES, 1, LOC_REC, 0, 0, 256, 8, BR_CLUST, MC_B1_7, MC_1_17, 0, 1, disp++,
             "map",
             QT_TRANSLATE_NOOP("Filter", "Locate biome center 1:256"),
             QT_TRANSLATE_NOOP("Filter",
             "Finds the center position of a given biome. Based on the 1:256 biome layer.")
         };
         list[F_TEMPS] = FilterInfo{
-            CAT_BIOMES, 1, 1, 1, 0, 0, 0, 1024, 10, 0, MC_1_7, MC_1_17, 0, 0, disp++,
+            CAT_BIOMES, 1, LOC_REC, 0, 0, 1024, 10, BR_NONE, MC_1_7, MC_1_17, 0, 0, disp++,
             "tempcat",
             QT_TRANSLATE_NOOP("Filter", "Temperature categories"),
             QT_TRANSLATE_NOOP("Filter",
@@ -383,35 +367,35 @@ static const struct FilterList
         };
 
         list[F_BIOME_NETHER_1] = FilterInfo{
-            CAT_NETHER, 1, 1, 1, 0, 0, 0, 1, 0, 0, MC_1_16_1, 0, -1, 1, disp++, // disabled
+            CAT_NETHER, 1, LOC_REC, 0, 0, 1, 0, BR_NONE, MC_1_16_1, 0, -1, 1, disp++, // disabled
             "nether",
             QT_TRANSLATE_NOOP("Filter", "Nether biomes 1:1 (disabled)"),
             QT_TRANSLATE_NOOP("Filter",
             "Nether biomes after voronoi scaling to 1:1.")
         };
         list[F_BIOME_NETHER_4] = FilterInfo{
-            CAT_NETHER, 0, 1, 1, 0, 0, 0, 4, 2, 0, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
+            CAT_NETHER, 0, LOC_REC, 0, 0, 4, 2, BR_NONE, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
             "nether",
             QT_TRANSLATE_NOOP("Filter", "Nether biomes 1:4"),
             QT_TRANSLATE_NOOP("Filter",
             "Nether biomes with normal noise sampling at scale 1:4.")
         };
         list[F_BIOME_NETHER_16] = FilterInfo{
-            CAT_NETHER, 0, 1, 1, 0, 0, 0, 16, 4, 0, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
+            CAT_NETHER, 0, LOC_REC, 0, 0, 16, 4, BR_NONE, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
             "nether",
             QT_TRANSLATE_NOOP("Filter", "Nether biomes 1:16"),
             QT_TRANSLATE_NOOP("Filter",
             "Nether biomes, but only sampled at scale 1:16.")
         };
         list[F_BIOME_NETHER_64] = FilterInfo{
-            CAT_NETHER, 0, 1, 1, 0, 0, 0, 64, 6, 0, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
+            CAT_NETHER, 0, LOC_REC, 0, 0, 64, 6, BR_NONE, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
             "nether",
             QT_TRANSLATE_NOOP("Filter", "Nether biomes 1:64"),
             QT_TRANSLATE_NOOP("Filter",
             "Nether biomes, but only sampled at scale 1:64.")
         };
         list[F_BIOME_NETHER_256] = FilterInfo{
-            CAT_NETHER, 0, 1, 1, 0, 0, 0, 256, 8, 0, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
+            CAT_NETHER, 0, LOC_REC, 0, 0, 256, 8, BR_NONE, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
             "nether",
             QT_TRANSLATE_NOOP("Filter", "Nether biomes 1:256"),
             QT_TRANSLATE_NOOP("Filter",
@@ -419,28 +403,28 @@ static const struct FilterList
         };
 
         list[F_BIOME_END_1] = FilterInfo{
-            CAT_END, 1, 1, 1, 0, 0, 0, 1, 0, 0, MC_1_9, 0, +1, 1, disp++, // disabled
+            CAT_END, 1, LOC_REC, 0, 0, 1, 0, BR_NONE, MC_1_9, 0, +1, 1, disp++, // disabled
             "the_end",
             QT_TRANSLATE_NOOP("Filter", "End biomes 1:1 (disabled)"),
             QT_TRANSLATE_NOOP("Filter",
             "End biomes after voronoi scaling to 1:1.")
         };
         list[F_BIOME_END_4] = FilterInfo{
-            CAT_END, 0, 1, 1, 0, 0, 0, 4, 2, 0, MC_1_9, MC_NEWEST, +1, 0, disp++,
+            CAT_END, 0, LOC_REC, 0, 0, 4, 2, BR_NONE, MC_1_9, MC_NEWEST, +1, 0, disp++,
             "the_end",
             QT_TRANSLATE_NOOP("Filter", "End biomes 1:4"),
             QT_TRANSLATE_NOOP("Filter",
             "End biomes sampled at scale 1:4. Note this is just a simple upscale of 1:16.")
         };
         list[F_BIOME_END_16] = FilterInfo{
-            CAT_END, 0, 1, 1, 0, 0, 0, 16, 4, 0, MC_1_9, MC_NEWEST, +1, 0, disp++,
+            CAT_END, 0, LOC_REC, 0, 0, 16, 4, BR_NONE, MC_1_9, MC_NEWEST, +1, 0, disp++,
             "the_end",
             QT_TRANSLATE_NOOP("Filter", "End biomes 1:16"),
             QT_TRANSLATE_NOOP("Filter",
             "End biomes with normal sampling at scale 1:16.")
         };
         list[F_BIOME_END_64] = FilterInfo{
-            CAT_END, 0, 1, 1, 0, 0, 0, 64, 6, 0, MC_1_9, MC_NEWEST, +1, 0, disp++,
+            CAT_END, 0, LOC_REC, 0, 0, 64, 6, BR_NONE, MC_1_9, MC_NEWEST, +1, 0, disp++,
             "the_end",
             QT_TRANSLATE_NOOP("Filter", "End biomes 1:64"),
             QT_TRANSLATE_NOOP("Filter",
@@ -448,20 +432,20 @@ static const struct FilterList
         };
 
         list[F_SPAWN] = FilterInfo{
-            CAT_OTHER, 1, 1, 1, 1, 0, 0, 1, 0, 0, MC_B1_8, MC_NEWEST, 0, 0, disp++,
+            CAT_OTHER, 1, LOC_RAD, 0, 0, 1, 0, BR_NONE, MC_B1_8, MC_NEWEST, 0, 0, disp++,
             "spawn",
             QT_TRANSLATE_NOOP("Filter", "Spawn"),
             ""
         };
 
         list[F_SLIME] = FilterInfo{
-            CAT_OTHER, 0, 1, 1, 0, 0, 0, 16, 4, 1, MC_UNDEF, MC_NEWEST, 0, 0, disp++,
+            CAT_OTHER, 0, LOC_REC, 0, 0, 16, 4, BR_CLUST, MC_UNDEF, MC_NEWEST, 0, 0, disp++,
             "slime",
             QT_TRANSLATE_NOOP("Filter", "Slime chunk"),
             ""
         };
         list[F_HEIGHT] = FilterInfo{
-            CAT_OTHER, 0, 1, 0, 0, 0, 0, 4, 2, 0, MC_1_1, MC_NEWEST, 0, 0, disp++,
+            CAT_OTHER, 0, LOC_POS, 0, 0, 4, 2, BR_NONE, MC_1_1, MC_NEWEST, 0, 0, disp++,
             "height",
             QT_TRANSLATE_NOOP("Filter", "Surface height"),
             QT_TRANSLATE_NOOP("Filter",
@@ -469,7 +453,7 @@ static const struct FilterList
         };
 
         list[F_FIRST_STRONGHOLD] = FilterInfo{
-            CAT_OTHER, 0, 1, 1, 1, 0, 0, 1, 0, 0, MC_B1_8, MC_NEWEST, 0, 0, disp++,
+            CAT_OTHER, 0, LOC_RAD, 0, 0, 1, 0, BR_NONE, MC_B1_8, MC_NEWEST, 0, 0, disp++,
             "stronghold",
             QT_TRANSLATE_NOOP("Filter", "First stronghold"),
             QT_TRANSLATE_NOOP("Filter",
@@ -478,28 +462,28 @@ static const struct FilterList
         };
 
         list[F_STRONGHOLD] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, 0, 1, 0, 1, MC_B1_8, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, 0, 1, 0, BR_CLUST, MC_B1_8, MC_NEWEST, 0, 0, disp++,
             "stronghold",
             QT_TRANSLATE_NOOP("Filter", "Stronghold"),
             ""
         };
 
         list[F_VILLAGE] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Village, 1, 0, 1, MC_B1_8, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Village, 1, 0, BR_CLUST, MC_B1_8, MC_NEWEST, 0, 0, disp++,
             "village",
             QT_TRANSLATE_NOOP("Filter", "Village"),
             ""
         };
 
         list[F_MINESHAFT] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 0, 0, Mineshaft, 1, 0, 1, MC_B1_8, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Mineshaft, 1, 0, BR_CLUST, MC_B1_8, MC_NEWEST, 0, 0, disp++,
             "mineshaft",
             QT_TRANSLATE_NOOP("Filter", "Abandoned mineshaft"),
             ""
         };
 
         list[F_DESERT] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Desert_Pyramid, 1, 0, 1, MC_1_3, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Desert_Pyramid, 1, 0, BR_CLUST, MC_1_3, MC_NEWEST, 0, 0, disp++,
             "desert",
             QT_TRANSLATE_NOOP("Filter", "Desert pyramid"),
             QT_TRANSLATE_NOOP("Filter",
@@ -508,7 +492,7 @@ static const struct FilterList
         };
 
         list[F_JUNGLE] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Jungle_Temple, 1, 0, 1, MC_1_3, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Jungle_Temple, 1, 0, BR_CLUST, MC_1_3, MC_NEWEST, 0, 0, disp++,
             "jungle",
             QT_TRANSLATE_NOOP("Filter", "Jungle temple"),
             QT_TRANSLATE_NOOP("Filter",
@@ -517,28 +501,28 @@ static const struct FilterList
         };
 
         list[F_HUT] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Swamp_Hut, 1, 0, 1, MC_1_4, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Swamp_Hut, 1, 0, BR_CLUST, MC_1_4, MC_NEWEST, 0, 0, disp++,
             "hut",
             QT_TRANSLATE_NOOP("Filter", "Swamp hut"),
             ""
         };
 
         list[F_MONUMENT] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Monument, 1, 0, 1, MC_1_8, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Monument, 1, 0, BR_CLUST, MC_1_8, MC_NEWEST, 0, 0, disp++,
             "monument",
             QT_TRANSLATE_NOOP("Filter", "Ocean monument"),
             ""
         };
 
         list[F_IGLOO] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Igloo, 1, 0, 1, MC_1_9, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Igloo, 1, 0, BR_CLUST, MC_1_9, MC_NEWEST, 0, 0, disp++,
             "igloo",
             QT_TRANSLATE_NOOP("Filter", "Igloo"),
             ""
         };
 
         list[F_MANSION] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Mansion, 1, 0, 1, MC_1_11, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Mansion, 1, 0, BR_CLUST, MC_1_11, MC_NEWEST, 0, 0, disp++,
             "mansion",
             QT_TRANSLATE_NOOP("Filter", "Woodland mansion"),
             QT_TRANSLATE_NOOP("Filter",
@@ -547,21 +531,21 @@ static const struct FilterList
         };
 
         list[F_RUINS] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Ocean_Ruin, 1, 0, 1, MC_1_13, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Ocean_Ruin, 1, 0, BR_CLUST, MC_1_13, MC_NEWEST, 0, 0, disp++,
             "ruins",
             QT_TRANSLATE_NOOP("Filter", "Ocean ruins"),
             ""
         };
 
         list[F_SHIPWRECK] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Shipwreck, 1, 0, 1, MC_1_13, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Shipwreck, 1, 0, BR_CLUST, MC_1_13, MC_NEWEST, 0, 0, disp++,
             "shipwreck",
             QT_TRANSLATE_NOOP("Filter", "Shipwreck"),
             ""
         };
 
         list[F_TREASURE] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Treasure, 1, 0, 1, MC_1_13, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Treasure, 1, 0, BR_CLUST, MC_1_13, MC_NEWEST, 0, 0, disp++,
             "treasure",
             QT_TRANSLATE_NOOP("Filter", "Buried treasure"),
             QT_TRANSLATE_NOOP("Filter",
@@ -571,70 +555,70 @@ static const struct FilterList
         };
 
         list[F_WELL] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Desert_Well, 1, 0, 1, MC_1_13, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Desert_Well, 1, 0, BR_CLUST, MC_1_13, MC_NEWEST, 0, 0, disp++,
             "well",
             QT_TRANSLATE_NOOP("Filter", "Desert well"),
             ""
         };
 
         list[F_OUTPOST] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Outpost, 1, 0, 1, MC_1_14, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Outpost, 1, 0, BR_CLUST, MC_1_14, MC_NEWEST, 0, 0, disp++,
             "outpost",
             QT_TRANSLATE_NOOP("Filter", "Pillager outpost"),
             ""
         };
 
         list[F_ANCIENT_CITY] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Ancient_City, 1, 0, 1, MC_1_19, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Ancient_City, 1, 0, BR_CLUST, MC_1_19, MC_NEWEST, 0, 0, disp++,
             "ancient_city",
             QT_TRANSLATE_NOOP("Filter", "Ancient city"),
             ""
         };
 
         list[F_TRAILS] = FilterInfo{
-            CAT_STRUCT, 1, 1, 1, 1, 0, Trail_Ruin, 1, 0, 1, MC_1_20, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 1, LOC_RAD, 0, Trail_Ruin, 1, 0, BR_CLUST, MC_1_20, MC_NEWEST, 0, 0, disp++,
             "trails",
             QT_TRANSLATE_NOOP("Filter", "Trail ruins"),
             ""
         };
 
         list[F_PORTAL] = FilterInfo{
-            CAT_STRUCT, 0, 1, 1, 1, 0, Ruined_Portal, 1, 0, 1, MC_1_16_1, MC_NEWEST, 0, 0, disp++,
+            CAT_STRUCT, 0, LOC_RAD, 0, Ruined_Portal, 1, 0, BR_CLUST, MC_1_16_1, MC_NEWEST, 0, 0, disp++,
             "portal",
             QT_TRANSLATE_NOOP("Filter", "Ruined portal (overworld)"),
             ""
         };
 
         list[F_PORTALN] = FilterInfo{
-            CAT_STRUCT, 0, 1, 1, 1, 0, Ruined_Portal_N, 1, 0, 1, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
+            CAT_STRUCT, 0, LOC_RAD, 0, Ruined_Portal_N, 1, 0, BR_CLUST, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
             "portal",
             QT_TRANSLATE_NOOP("Filter", "Ruined portal (nether)"),
             ""
         };
 
         list[F_FORTRESS] = FilterInfo{
-            CAT_STRUCT, 0, 1, 1, 1, 0, Fortress, 1, 0, 1, MC_1_0, MC_NEWEST, -1, 0, disp++,
+            CAT_STRUCT, 0, LOC_RAD, 0, Fortress, 1, 0, BR_CLUST, MC_1_0, MC_NEWEST, -1, 0, disp++,
             "fortress",
             QT_TRANSLATE_NOOP("Filter", "Nether fortress"),
             ""
         };
 
         list[F_BASTION] = FilterInfo{
-            CAT_STRUCT, 0, 1, 1, 1, 0, Bastion, 1, 0, 1, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
+            CAT_STRUCT, 0, LOC_RAD, 0, Bastion, 1, 0, BR_CLUST, MC_1_16_1, MC_NEWEST, -1, 0, disp++,
             "bastion",
             QT_TRANSLATE_NOOP("Filter", "Bastion remnant"),
             ""
         };
 
         list[F_ENDCITY] = FilterInfo{
-            CAT_STRUCT, 0, 1, 1, 1, 0, End_City, 1, 0, 1, MC_1_9, MC_NEWEST, +1, 0, disp++,
+            CAT_STRUCT, 0, LOC_RAD, 0, End_City, 1, 0, BR_CLUST, MC_1_9, MC_NEWEST, +1, 0, disp++,
             "endcity",
             QT_TRANSLATE_NOOP("Filter", "End city"),
             ""
         };
 
         list[F_GATEWAY] = FilterInfo{
-            CAT_STRUCT, 0, 1, 1, 1, 0, End_Gateway, 1, 0, 1, MC_1_13, MC_NEWEST, +1, 0, disp++,
+            CAT_STRUCT, 0, LOC_RAD, 0, End_Gateway, 1, 0, BR_CLUST, MC_1_13, MC_NEWEST, +1, 0, disp++,
             "gateway",
             QT_TRANSLATE_NOOP("Filter", "End gateway"),
             QT_TRANSLATE_NOOP("Filter",
@@ -656,7 +640,8 @@ struct /*__attribute__((packed))*/ Condition
         VER_2_3_0       = 1,
         VER_2_4_0       = 2,
         VER_3_4_0       = 3,
-        VER_CURRENT     = VER_3_4_0,
+        VER_4_0_0       = 4,
+        VER_CURRENT     = VER_4_0_0,
     };
     enum { // meta flags
         DISABLED        = 0x0001,
@@ -699,7 +684,7 @@ struct /*__attribute__((packed))*/ Condition
     uint8_t     minmax;
     uint8_t     para;
     uint8_t     octave;
-    uint8_t     pad2[2]; // legacy zero initialized
+    uint16_t    step;
     uint16_t    version; // condition data version
     uint64_t    biomeToExcl, biomeToExclM; // exclusion biomes
     int32_t     temps[9];
@@ -714,6 +699,8 @@ struct /*__attribute__((packed))*/ Condition
     int32_t     limex[NP_MAX][2];
     float       vmin;
     float       vmax;
+    float       converage;
+    float       confidence;
 
     // generated members - initialized when the search is started
     uint8_t     generated_start[0]; // address dummy
@@ -732,7 +719,7 @@ struct /*__attribute__((packed))*/ Condition
 };
 
 static_assert(
-    offsetof(Condition, generated_start) == 312,
+    offsetof(Condition, generated_start) == 320,
     "Layout of Condition has changed!"
 );
 
diff --git a/src/searchthread.cpp b/src/searchthread.cpp
index e7ead2d..fc7449d 100644
--- a/src/searchthread.cpp
+++ b/src/searchthread.cpp
@@ -261,7 +261,7 @@ bool SearchMaster::set(QWidget *widget, const Session& s)
             {
                 Generator tmp;
                 setupGenerator(&tmp, s.wi.mc, 0);
-                const Layer *l = getLayerForScale(&tmp, finfo.step);
+                const Layer *l = getLayerForScale(&tmp, finfo.grid);
                 if (l)
                     layerId = l - tmp.ls.layers;
             }
@@ -281,12 +281,12 @@ bool SearchMaster::set(QWidget *widget, const Session& s)
         }
         if (c.type == F_TEMPS)
         {
-            int w = c.x2 - c.x1 + 1;
-            int h = c.z2 - c.z1 + 1;
+            int w = (c.x2 >> 10) - (c.x1 >> 10) + 1;
+            int h = (c.z2 >> 10) - (c.z1 >> 10) + 1;
             if (c.count > w * h)
             {
                 QString msg = tr("Temperature category condition with ID %1 has too "
-                                 "many restrictions (%2) for the area (%3 x %4).");
+                                 "many restrictions (%2) for the area (%3 x %4 @ scale 1:1024).");
                 warn(widget, msg.arg(cid).arg(c.count).arg(w).arg(h));
                 return false;
             }
@@ -733,6 +733,7 @@ void SearchMaster::stop()
         }
     }
     workers.clear();
+
     emit searchFinish(false);
 }
 
diff --git a/src/tabbiomes.cpp b/src/tabbiomes.cpp
index 73b0d32..7c099ea 100644
--- a/src/tabbiomes.cpp
+++ b/src/tabbiomes.cpp
@@ -836,17 +836,14 @@ void TabBiomes::on_pushExport_clicked()
 void TabBiomes::on_buttonFromVisible_clicked()
 {
     MapView *mapview = parent->getMapView();
-    qreal uiw = mapview->width() * mapview->getScale();
-    qreal uih = mapview->height() * mapview->getScale();
-    int bx0 = (int) floor(mapview->getX() - uiw/2);
-    int bz0 = (int) floor(mapview->getZ() - uih/2);
-    int bx1 = (int) ceil(mapview->getX() + uiw/2);
-    int bz1 = (int) ceil(mapview->getZ() + uih/2);
 
-    ui->lineX1->setText( QString::number(bx0) );
-    ui->lineZ1->setText( QString::number(bz0) );
-    ui->lineX2->setText( QString::number(bx1) );
-    ui->lineZ2->setText( QString::number(bz1) );
+    int x1, z1, x2, z2;
+    mapview->getVisible(&x1, &z1, &x2, &z2);
+
+    ui->lineX1->setText( QString::number(x1) );
+    ui->lineZ1->setText( QString::number(z1) );
+    ui->lineX2->setText( QString::number(x2) );
+    ui->lineZ2->setText( QString::number(z2) );
 }
 
 void TabBiomes::on_radioFullSample_toggled(bool checked)
diff --git a/src/tablocations.cpp b/src/tablocations.cpp
new file mode 100644
index 0000000..02906a4
--- /dev/null
+++ b/src/tablocations.cpp
@@ -0,0 +1,437 @@
+#include "tablocations.h"
+#include "ui_tablocations.h"
+
+#include "message.h"
+#include "util.h"
+#include "config.h"
+
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include 
+#include 
+#include 
+
+#define SAMPLES_MAX 9999999
+
+static
+QTreeWidgetItem *setConditionTreeItems(ConditionTree& ctree, int node, int64_t seed, Pos cpos[], QTreeWidgetItem* parent, bool posval)
+{
+    Condition& c = ctree.condvec[node];
+    Pos p = cpos[c.save];
+    const std::vector& branches = ctree.references[c.save];
+    QTreeWidgetItem* item;
+
+    if (c.type == 0)
+    {
+        item = parent;
+    }
+    else
+    {
+        item = new QTreeWidgetItem(parent);
+        item->setText(0, c.summary(false));
+
+        if ((p.x == -1 && p.z == -1) || c.type == F_LOGIC_NOT)
+            posval = false;
+        if (posval)
+        {
+            const FilterInfo& finfo = g_filterinfo.list[c.type];
+            double dist = sqrt((double)p.x*p.x + (double)p.z*p.z);
+            item->setText(1, QString::number(p.x));
+            item->setText(2, QString::number(p.z));
+            item->setText(3, QString::asprintf("%.0f", dist));
+            item->setData(0, Qt::UserRole+0, QVariant::fromValue(seed));
+            item->setData(0, Qt::UserRole+1, QVariant::fromValue(finfo.dim));
+            item->setData(0, Qt::UserRole+2, QVariant::fromValue(p));
+        }
+    }
+    if (!branches.empty())
+    {
+        for (char b : branches)
+            setConditionTreeItems(ctree, b, seed, cpos, item, posval);
+    }
+    return item;
+}
+
+QString AnalysisLocations::set(WorldInfo wi, const QVector& conds)
+{
+    this->wi = wi;
+    QString err = condtree.set(conds, wi.mc);
+    if (err.isEmpty())
+        err = env.init(wi.mc, wi.large, &condtree);
+    if (!err.isEmpty())
+        env.setSeed(wi.seed);
+    return err;
+}
+
+void AnalysisLocations::run()
+{
+    stop = false;
+
+    for (idx = 0; idx < (long)pos.size(); idx++)
+    {
+        if (stop) break;
+
+        Pos at = pos[idx.load()];
+        Pos cpos[MAX_INSTANCES] = {};
+        if (testTreeAt(at, &env, PASS_FULL_64, &stop, cpos)
+            != COND_OK)
+        {
+            continue;
+        }
+
+        double dist = sqrt((double)at.x*at.x + (double)at.z*at.z);
+
+        QTreeWidgetItem *item = new QTreeWidgetItem();
+        item->setText(0, tr("origin"));
+        item->setText(1, QString::number(at.x));
+        item->setText(2, QString::number(at.z));
+        item->setText(3, QString::asprintf("%.0f", dist));
+        item->setData(0, Qt::UserRole+0, QVariant::fromValue(env.seed));
+        item->setData(0, Qt::UserRole+1, QVariant::Invalid);
+        item->setData(0, Qt::UserRole+2, QVariant::fromValue(at));
+
+        setConditionTreeItems(condtree, 0, env.seed, cpos, item, true);
+        emit itemDone(item);
+    }
+}
+
+
+enum { SMODE_RADIAL_GRID, SMODE_SQUARE_SPIRAL, SMODE_NORMAL };
+
+TabLocations::TabLocations(MainWindow *parent)
+    : QWidget(parent)
+    , ui(new Ui::TabLocations)
+    , parent(parent)
+    , thread()
+    , timer()
+    , maxresults(1)
+    , nextupdate()
+    , updt(20)
+{
+    ui->setupUi(this);
+    ui->treeWidget->setSortingEnabled(false); // sortable triggers are not necessary
+
+    ui->comboSampling->addItem(tr("Lattice points in radial order") + ", ||α·n, α·m|| < r", SMODE_RADIAL_GRID);
+    ui->comboSampling->addItem(tr("Square spiral") + ", (α·n, α·m)", SMODE_SQUARE_SPIRAL);
+    ui->comboSampling->addItem(tr("Random Gaussian samples") + ", (α·norm(), α·norm())", SMODE_NORMAL);
+
+    ui->lineN->setValidator(new QIntValidator(1, SAMPLES_MAX, this));
+    ui->lineA->setValidator(new QIntValidator(1, (int)3e7, this));
+    ui->lineX->setValidator(new QIntValidator((int)-3e7, (int)3e7, this));
+    ui->lineZ->setValidator(new QIntValidator((int)-3e7, (int)3e7, this));
+
+    connect(&thread, &AnalysisLocations::warning, this, &TabLocations::warning, Qt::BlockingQueuedConnection);
+    connect(&thread, &AnalysisLocations::itemDone, this, &TabLocations::onAnalysisItemDone, Qt::BlockingQueuedConnection);
+    connect(&thread, &AnalysisLocations::finished, this, &TabLocations::onAnalysisFinished);
+
+    connect(&timer, &QTimer::timeout, this, QOverload<>::of(&TabLocations::onProgressTimeout));
+}
+
+TabLocations::~TabLocations()
+{
+    timer.stop();
+    thread.stop = true;
+    thread.wait(500);
+    delete ui;
+}
+
+bool TabLocations::event(QEvent *e)
+{
+    if (e->type() == QEvent::LayoutRequest)
+    {
+        QFontMetrics fm = QFontMetrics(ui->treeWidget->font());
+        ui->treeWidget->setColumnWidth(0, fm.horizontalAdvance('#') * 32);
+        ui->treeWidget->setColumnWidth(1, fm.horizontalAdvance('#') * 9);
+        ui->treeWidget->setColumnWidth(2, fm.horizontalAdvance('#') * 9);
+        ui->treeWidget->setColumnWidth(3, fm.horizontalAdvance('#') * 9);
+    }
+    return QWidget::event(e);
+}
+
+void TabLocations::save(QSettings& settings)
+{
+    settings.setValue("analysis/samplemode", ui->comboSampling->currentData().toInt());
+    settings.setValue("analysis/samplecnt", ui->lineN->text().toInt());
+    settings.setValue("analysis/samplesep", ui->lineA->text().toInt());
+    settings.setValue("analysis/offx", ui->lineX->text().toInt());
+    settings.setValue("analysis/offz", ui->lineZ->text().toInt());
+}
+
+static void loadLine(QSettings *s, QLineEdit *line, const char *key)
+{
+    qlonglong x = line->text().toLongLong();
+    line->setText( QString::number(s->value(key, x).toLongLong()) );
+}
+void TabLocations::load(QSettings& settings)
+{
+    loadLine(&settings, ui->lineN, "analysis/samplecnt");
+    loadLine(&settings, ui->lineA, "analysis/samplesep");
+    loadLine(&settings, ui->lineX, "analysis/offx");
+    loadLine(&settings, ui->lineZ, "analysis/offz");
+    QVariant mode = settings.value("analysis/samplemode", ui->comboSampling->currentData());
+    ui->comboSampling->setCurrentIndex(ui->comboSampling->findData(mode));
+
+    maxresults = settings.value("config/maxMatching", maxresults).toInt();
+}
+
+int TabLocations::warning(QString text, QMessageBox::StandardButtons buttons)
+{
+    return warn(parent, text, buttons);
+}
+
+void TabLocations::onAnalysisItemDone(QTreeWidgetItem *item)
+{
+    if (qbuf.size() + ui->treeWidget->topLevelItemCount() >= maxresults)
+    {
+        thread.stop = true;
+    }
+
+    qbuf.push_back(item);
+    quint64 ns = elapsed.nsecsElapsed();
+    if (ns > nextupdate)
+    {
+        nextupdate = ns + updt * 1e6;
+        QTimer::singleShot(updt, this, &TabLocations::onBufferTimeout);
+    }
+}
+
+void TabLocations::onAnalysisFinished()
+{
+    timer.stop();
+    onBufferTimeout();
+    ui->pushExport->setEnabled(ui->treeWidget->topLevelItemCount() > 0);
+    ui->pushStart->setChecked(false);
+    ui->pushStart->setText(tr("Analyze"));
+}
+
+void TabLocations::onBufferTimeout()
+{
+    uint64_t t = -elapsed.elapsed();
+
+    if (!qbuf.empty())
+    {
+        ui->treeWidget->setUpdatesEnabled(false);
+        ui->treeWidget->addTopLevelItems(qbuf);
+        ui->treeWidget->setUpdatesEnabled(true);
+        qbuf.clear();
+        onProgressTimeout();
+    }
+
+    QApplication::processEvents(); // force processing of events so we can time correctly
+
+    t += elapsed.elapsed();
+    if (8*t > updt)
+        updt = 4*t;
+    nextupdate = elapsed.nsecsElapsed() + 1e6 * updt;
+}
+
+void TabLocations::onProgressTimeout()
+{
+    QString progress = QString::asprintf(" (%ld/%zu)", thread.idx.load(), thread.pos.size());
+    ui->pushStart->setText(tr("Stop") + progress);
+}
+
+void TabLocations::on_pushStart_clicked()
+{
+    if (thread.isRunning())
+    {
+        thread.stop = true;
+        return;
+    }
+    updt = 20;
+    nextupdate = 0;
+    elapsed.start();
+
+    thread.pos.clear();
+    int mode = ui->comboSampling->currentData().toInt();
+    int a = ui->lineA->text().toInt();
+    uint64_t n = ui->lineN->text().toULongLong();
+    int x0 = ui->lineX->text().toInt();
+    int z0 = ui->lineZ->text().toInt();
+
+    if (a == 0)
+        return;
+    if (n > SAMPLES_MAX)
+        return;
+
+    WorldInfo wi;
+    parent->getSeed(&wi);
+    QVector conds = parent->formCond->getConditions();
+
+    QString err = thread.set(wi, conds);
+    if (!err.isEmpty())
+    {
+        emit warning(err, QMessageBox::Ok);
+        return;
+    }
+
+    if (mode == SMODE_RADIAL_GRID)
+    {
+        struct P {
+            int x, z;
+            uint64_t rsq;
+            bool operator< (const P& x) const { return rsq < x.rsq; }
+        };
+        std::vector
 v;
+        uint64_t rsqmax = (uint64_t) ceil(n / M_PI);
+        int64_t r = (int64_t) sqrt(rsqmax);
+
+        for (int64_t x = -r; x <= r; x++)
+        {
+            for (int64_t z = -r; z <= r; z++)
+            {
+                uint64_t rsq = (uint64_t)(x * x + z * z);
+                if (rsq <= rsqmax)
+                    v.push_back(P{(int)x, (int)z, rsq});
+            }
+        }
+        std::sort(v.begin(), v.end());
+        for (uint64_t i = 0; i < n && i < v.size(); i++)
+        {
+            Pos p = { a*v[i].x + x0, a*v[i].z + z0};
+            thread.pos.push_back(p);
+        }
+    }
+    else if (mode == SMODE_SQUARE_SPIRAL)
+    {
+        int rx = 0;
+        int rz = 0;
+        int i = 0, dl = 1;
+        int dx = 1, dz = 0;
+        for (uint64_t j = 0; j < n; j++)
+        {
+            Pos p = { a*rx + x0, a*rz + z0 };
+            thread.pos.push_back(p);
+            rx += dx;
+            rz += dz;
+            if (++i == dl)
+            {
+                i = 0;
+                int tmp = dx;
+                dx = -dz;
+                dz = tmp;
+                if (dz == 0)
+                    dl++;
+            }
+        }
+    }
+    else if (mode == SMODE_NORMAL)
+    {
+        thread_local RandGen rng;
+        std::normal_distribution norm = std::normal_distribution(0.0, 1.0);
+
+        for (uint64_t j = 0; j < n; j++)
+        {
+            int x = (int) round( a * norm(rng.mt) );
+            int z = (int) round( a * norm(rng.mt) );
+            Pos p = { x + x0, z + z0 };
+            thread.pos.push_back(p);
+        }
+    }
+
+    //ui->treeWidget->setSortingEnabled(false);
+    while (ui->treeWidget->topLevelItemCount() > 0)
+        delete ui->treeWidget->takeTopLevelItem(0);
+
+    ui->pushExport->setEnabled(false);
+    ui->pushStart->setChecked(true);
+    QString progress = QString::asprintf(" (0/%zu)", thread.pos.size());
+    ui->pushStart->setText(tr("Stop") + progress);
+    timer.start(250);
+    thread.start();
+}
+
+void TabLocations::on_treeWidget_itemClicked(QTreeWidgetItem *item, int column)
+{
+    (void) column;
+    QVariant dat;
+    dat = item->data(0, Qt::UserRole+0);
+    if (dat.isValid())
+    {
+        uint64_t seed = qvariant_cast(dat);
+        dat = item->data(0, Qt::UserRole+1);
+        int dim = dat.isValid() ? dat.toInt() : DIM_UNDEF;
+        WorldInfo wi;
+        parent->getSeed(&wi);
+        wi.seed = seed;
+        parent->setSeed(wi, dim);
+    }
+
+    dat = item->data(0, Qt::UserRole+2);
+    if (dat.isValid())
+    {
+        Pos p = qvariant_cast(dat);
+        parent->getMapView()->setView(p.x+0.5, p.z+0.5);
+    }
+}
+
+void TabLocations::on_pushExpand_clicked()
+{
+    bool expand = false;
+    for (QTreeWidgetItemIterator it(ui->treeWidget); *it; ++it)
+        if (!(*it)->isExpanded())
+            expand = true;
+    if (expand)
+        ui->treeWidget->expandAll();
+    else
+        ui->treeWidget->collapseAll();
+}
+
+static
+void csvline(QTextStream& stream, const QString& qte, const QString& sep, QStringList& cols)
+{
+    if (qte.isEmpty())
+    {
+        for (QString& s : cols)
+            if (s.contains(sep))
+                s = "\"" + s + "\"";
+    }
+    stream << qte << cols.join(sep) << qte << "\n";
+}
+
+void TabLocations::on_pushExport_clicked()
+{
+    QString fnam = QFileDialog::getSaveFileName(
+        this, tr("Export trigger analysis"), parent->prevdir, tr("Text files (*.txt *csv);;Any files (*)"));
+    if (fnam.isEmpty())
+        return;
+
+    QFileInfo finfo(fnam);
+    QFile file(fnam);
+    parent->prevdir = finfo.absolutePath();
+
+    if (!file.open(QIODevice::WriteOnly))
+    {
+        warn(parent, tr("Failed to open file for export:\n\"%1\"").arg(fnam));
+        return;
+    }
+
+    QString qte = parent->config.quote;
+    QString sep = parent->config.separator;
+
+    QTextStream stream(&file);
+    stream << "Sep=" + sep + "\n";
+    sep = qte + sep + qte;
+
+    QStringList header = { tr("condition"), tr("x"), tr("z") };
+    csvline(stream, qte, sep, header);
+
+    QTreeWidgetItemIterator it(ui->treeWidget);
+    for (; *it; ++it)
+    {
+        QTreeWidgetItem *item = *it;
+        QStringList cols;
+        for (int i = 0, n = item->columnCount(); i < n; i++)
+        {
+            QString s = item->text(i);
+            if (s == "-") s = "";
+            cols.append(s);
+        }
+        csvline(stream, qte, sep, cols);
+    }
+}
+
diff --git a/src/tablocations.h b/src/tablocations.h
new file mode 100644
index 0000000..6dcb9e0
--- /dev/null
+++ b/src/tablocations.h
@@ -0,0 +1,78 @@
+#ifndef TABLOCATIONS_H
+#define TABLOCATIONS_H
+
+#include 
+#include 
+#include 
+
+#include "mainwindow.h"
+#include "search.h"
+#include "world.h"
+
+namespace Ui {
+class TabLocations;
+}
+
+class AnalysisLocations : public QThread
+{
+    Q_OBJECT
+public:
+    explicit AnalysisLocations(QObject *parent = nullptr)
+        : QThread(parent), wi(),stop(),idx() {}
+
+    QString set(WorldInfo wi, const QVector& conds);
+
+    virtual void run() override;
+
+signals:
+    void itemDone(QTreeWidgetItem *item);
+    int warning(QString text, QMessageBox::StandardButtons buttons);
+
+public:
+    WorldInfo wi;
+    ConditionTree condtree;
+    SearchThreadEnv env;
+    std::vector pos;
+    std::atomic_bool stop;
+    std::atomic_long idx;
+};
+
+class TabLocations : public QWidget, public ISaveTab
+{
+    Q_OBJECT
+
+public:
+    explicit TabLocations(MainWindow *parent = nullptr);
+    ~TabLocations();
+
+    virtual bool event(QEvent *e) override;
+
+    virtual void save(QSettings& settings) override;
+    virtual void load(QSettings& settings) override;
+
+private slots:
+    int warning(QString text, QMessageBox::StandardButtons buttons);
+    void onAnalysisItemDone(QTreeWidgetItem *item);
+    void onAnalysisFinished();
+    void onBufferTimeout();
+    void onProgressTimeout();
+
+    void on_pushStart_clicked();
+    void on_pushExpand_clicked();
+    void on_pushExport_clicked();
+    void on_treeWidget_itemClicked(QTreeWidgetItem *item, int column);
+
+private:
+    Ui::TabLocations *ui;
+    MainWindow *parent;
+    AnalysisLocations thread;
+    QTimer timer;
+    int maxresults;
+
+    QElapsedTimer elapsed;
+    uint64_t nextupdate;
+    uint64_t updt;
+    QList qbuf;
+};
+
+#endif // TABLOCATIONS_H
diff --git a/src/tablocations.ui b/src/tablocations.ui
new file mode 100644
index 0000000..65da83d
--- /dev/null
+++ b/src/tablocations.ui
@@ -0,0 +1,175 @@
+
+
+ TabLocations
+ 
+  
+   Form
+  
+  
+   
+    
+     
+      Centered on:
+     
+    
+   
+   
+    
+     
+      Sampling strategy:
+     
+    
+   
+   
+    
+     
+      <html><head/><body><p>X:</p></body></html>
+     
+    
+   
+   
+    
+     
+      512
+     
+    
+   
+   
+    
+     
+      
+       0
+       0
+      
+     
+    
+   
+   
+    
+   
+   
+    
+     
+      
+       Monospace
+      
+     
+     
+      QAbstractItemView::NoEditTriggers
+     
+     
+      QAbstractItemView::NoDragDrop
+     
+     
+      12
+     
+     
+      true
+     
+     
+      false
+     
+     
+      100
+     
+     
+      
+       condition
+      
+      
+       
+        Monospace
+       
+      
+     
+     
+      
+       x
+      
+      
+       
+        Monospace
+       
+      
+     
+     
+      
+       z
+      
+      
+       
+        Monospace
+       
+      
+     
+     
+      
+       distance
+      
+     
+    
+   
+   
+    
+   
+   
+    
+     
+      
+       
+        false
+       
+       
+        Export...
+       
+      
+     
+     
+      
+       
+        Expand all
+       
+      
+     
+     
+      
+       
+        Analyze
+       
+      
+     
+    
+   
+   
+    
+     
+      Z:
+     
+    
+   
+   
+    
+     
+      Spread (α):
+     
+    
+   
+   
+    
+     
+      1000
+     
+    
+   
+   
+    
+     
+      Number of samples:
+     
+    
+   
+  
+ 
+ 
+ 
+
diff --git a/src/tabstructures.cpp b/src/tabstructures.cpp
index c7c3906..b94437b 100644
--- a/src/tabstructures.cpp
+++ b/src/tabstructures.cpp
@@ -607,17 +607,14 @@ void TabStructures::on_pushExport_clicked()
 void TabStructures::on_buttonFromVisible_clicked()
 {
     MapView *mapview = parent->getMapView();
-    qreal uiw = mapview->width() * mapview->getScale();
-    qreal uih = mapview->height() * mapview->getScale();
-    int bx0 = (int) floor(mapview->getX() - uiw/2);
-    int bz0 = (int) floor(mapview->getZ() - uih/2);
-    int bx1 = (int) ceil(mapview->getX() + uiw/2);
-    int bz1 = (int) ceil(mapview->getZ() + uih/2);
 
-    ui->lineX1->setText( QString::number(bx0) );
-    ui->lineZ1->setText( QString::number(bz0) );
-    ui->lineX2->setText( QString::number(bx1) );
-    ui->lineZ2->setText( QString::number(bz1) );
+    int x1, z1, x2, z2;
+    mapview->getVisible(&x1, &z1, &x2, &z2);
+
+    ui->lineX1->setText( QString::number(x1) );
+    ui->lineZ1->setText( QString::number(z1) );
+    ui->lineX2->setText( QString::number(x2) );
+    ui->lineZ2->setText( QString::number(z2) );
 }
 
 void TabStructures::on_tabWidget_currentChanged(int)
diff --git a/src/tabtriggers.cpp b/src/tabtriggers.cpp
index 42783ba..23b0cda 100644
--- a/src/tabtriggers.cpp
+++ b/src/tabtriggers.cpp
@@ -136,15 +136,12 @@ bool TabTriggers::event(QEvent *e)
     return QWidget::event(e);
 }
 
-void TabTriggers::save(QSettings& settings)
+void TabTriggers::save(QSettings&)
 {
-    settings.setValue("analysis/seedsrc", ui->comboSeedSource->currentIndex());
 }
 
-void TabTriggers::load(QSettings& settings)
+void TabTriggers::load(QSettings&)
 {
-    int idx = settings.value("analysis/seedsrc", ui->comboSeedSource->currentIndex()).toInt();
-    ui->comboSeedSource->setCurrentIndex(idx);
 }
 
 int TabTriggers::warning(QString text, QMessageBox::StandardButtons buttons)
@@ -251,7 +248,14 @@ void TabTriggers::on_treeWidget_itemClicked(QTreeWidgetItem *item, int column)
 
 void TabTriggers::on_pushExpand_clicked()
 {
-    ui->treeWidget->expandAll();
+    bool expand = false;
+    for (QTreeWidgetItemIterator it(ui->treeWidget); *it; ++it)
+        if (!(*it)->isExpanded())
+            expand = true;
+    if (expand)
+        ui->treeWidget->expandAll();
+    else
+        ui->treeWidget->collapseAll();
 }
 
 static
diff --git a/src/tabtriggers.ui b/src/tabtriggers.ui
index b32190e..c6d1a78 100644
--- a/src/tabtriggers.ui
+++ b/src/tabtriggers.ui
@@ -83,7 +83,7 @@
    
     
      
-      Analyze the search condition triggers.
+      Examine how the conditions are evaluated.
      
     
    
diff --git a/src/util.cpp b/src/util.cpp
index c826fed..295b225 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -160,30 +160,24 @@ QString getBiomeDisplay(int mc, int id)
     return name ? name : "";
 }
 
+RandGen::RandGen()
+{
+    std::random_device rd;
+    if (rd.entropy())
+        mt = std::mt19937_64(rd());
+    else
+        mt = std::mt19937_64(time(0));
+}
+
 // get a random 64-bit integer
 uint64_t getRnd64()
 {
     static QMutex mutex;
-    static std::random_device rd;
-    static std::mt19937_64 mt(rd());
-    static uint64_t x = (uint64_t) time(0);
+    static RandGen rng;
     uint64_t ret = 0;
     mutex.lock();
-    if (rd.entropy())
-    {
-        std::uniform_int_distribution d;
-        ret = d(mt);
-    }
-    else
-    {
-        const uint64_t c = 0xd6e8feb86659fd93ULL;
-        x ^= x >> 32;
-        x *= c;
-        x ^= x >> 32;
-        x *= c;
-        x ^= x >> 32;
-        ret = x;
-    }
+    std::uniform_int_distribution d;
+    ret = d(rng.mt);
     mutex.unlock();
     return ret;
 }
diff --git a/src/util.h b/src/util.h
index 3a05a08..1cfc475 100644
--- a/src/util.h
+++ b/src/util.h
@@ -64,6 +64,12 @@ QString getStartPieceName(int stype, const StructureVariant *sv);
 
 QString getBiomeDisplay(int mc, int id);
 
+struct RandGen
+{
+    RandGen();
+    std::mt19937_64 mt;
+};
+
 // get a random 64-bit integer
 uint64_t getRnd64();
 
diff --git a/src/world.cpp b/src/world.cpp
index 9ddde9d..b999653 100644
--- a/src/world.cpp
+++ b/src/world.cpp
@@ -1224,6 +1224,8 @@ void QWorld::draw(QPainter& painter, int vw, int vh, qreal focusx, qreal focusz,
         painter.drawImage(rec, slimeimg);
     }
 
+    // draw bounding boxes and shapes
+    painter.setPen(QPen(QColor(192, 0, 0, 160), 1));
 
     if (showBB && blocks2pix >= 1.0 && qsinfo && dim == 0)
     {
@@ -1237,7 +1239,6 @@ void QWorld::draw(QPainter& painter, int vw, int vh, qreal focusx, qreal focusz,
             qreal x = vw/2.0 + (qi.afk.x - focusx) * blocks2pix;
             qreal y = vh/2.0 + (qi.afk.z - focusz) * blocks2pix;
             qreal r = 128.0 * blocks2pix;
-            painter.setPen(QPen(QColor(192, 0, 0, 160), 1));
             painter.drawEllipse(QRectF(x-r, y-r, 2*r, 2*r));
             r = 16;
             painter.drawLine(QPointF(x-r,y), QPointF(x+r,y));
@@ -1245,6 +1246,29 @@ void QWorld::draw(QPainter& painter, int vw, int vh, qreal focusx, qreal focusz,
         }
     }
 
+    for (Shape& s : shapes)
+    {
+        if (s.dim != dim)
+            continue;
+        qreal x1 = vw/2.0 + (s.p1.x - focusx) * blocks2pix;
+        qreal y1 = vh/2.0 + (s.p1.z - focusz) * blocks2pix;
+        qreal x2 = vw/2.0 + (s.p2.x - focusx) * blocks2pix;
+        qreal y2 = vh/2.0 + (s.p2.z - focusz) * blocks2pix;
+        qreal r = s.r * blocks2pix;
+        switch (s.type)
+        {
+        case Shape::RECT:
+            painter.drawRect(QRectF(x1, y1, x2-x1, y2-y1));
+            break;
+        case Shape::LINE:
+            painter.drawLine(QLineF(x1, y1, x2, y2));
+            break;
+        case Shape::CIRCLE:
+            painter.drawEllipse(QPointF(x1, y1), r, r);
+            break;
+        }
+    }
+
     for (int sopt = D_DESERT; sopt < D_SPAWN; sopt++)
     {
         Level& l = lvs[sopt];
diff --git a/src/world.h b/src/world.h
index fb71930..51750e4 100644
--- a/src/world.h
+++ b/src/world.h
@@ -121,6 +121,14 @@ struct PosElement
     Pos p;
 };
 
+struct Shape
+{
+    enum { RECT, LINE, CIRCLE } type;
+    int dim;
+    int r;
+    Pos p1, p2;
+};
+
 class MapWorker : public QThread
 {
     Q_OBJECT
@@ -206,6 +214,9 @@ public:
     QImage slimeimg;
     long slimex, slimez;
 
+    // shapes to overlay
+    std::vector shapes;
+
     // structure selection from mouse position
     bool seldo;
     qreal selx, selz;