diff --git a/cubiomes b/cubiomes
index 0af31b4..e49c8c5 160000
--- a/cubiomes
+++ b/cubiomes
@@ -1 +1 @@
-Subproject commit 0af31b4e7eeb14a58c2bd9a4c4c68b97b4a7d6e8
+Subproject commit e49c8c561bcd238b376b7817182695ea2f993061
diff --git a/cubiomes-viewer.pro b/cubiomes-viewer.pro
index 9e8b305..f148e7e 100644
--- a/cubiomes-viewer.pro
+++ b/cubiomes-viewer.pro
@@ -141,6 +141,7 @@ HEADERS += \
         $$CUPATH/finders.h \
         $$CUPATH/generator.h \
         $$CUPATH/layers.h \
+        $$CUPATH/biomes.h \
         $$CUPATH/quadbase.h \
         $$CUPATH/util.h \
         $$LUAPATH/lapi.h \
diff --git a/rc/icons/chambers.png b/rc/icons/chambers.png
index 880d34b..55c8a38 100644
Binary files a/rc/icons/chambers.png and b/rc/icons/chambers.png differ
diff --git a/rc/icons/chambers_d.png b/rc/icons/chambers_d.png
index 880d34b..1c8025b 100644
Binary files a/rc/icons/chambers_d.png and b/rc/icons/chambers_d.png differ
diff --git a/src/config.cpp b/src/config.cpp
index f695c18..40f6bc2 100644
--- a/src/config.cpp
+++ b/src/config.cpp
@@ -60,7 +60,7 @@ bool WorldInfo::equals(const WorldInfo& wi) const
 
 void WorldInfo::reset()
 {
-    mc = MC_NEWEST;
+    mc = MC_DEFAULT;
     large = false;
     seed = 0;
     y = 255;
@@ -92,7 +92,7 @@ bool WorldInfo::read(const QString& line)
     {
         mc = str2mc(buf);
         if (mc < 0)
-            mc = MC_NEWEST;
+            mc = MC_DEFAULT;
         return true;
     }
     if (sscanf(p, "#Large:    %d", &tmp) == 1)
diff --git a/src/config.h b/src/config.h
index 4909816..35fdd55 100644
--- a/src/config.h
+++ b/src/config.h
@@ -15,6 +15,7 @@
 
 #define PRECOMPUTE48_BUFSIZ ((int64_t)1 << 30)
 
+enum { MC_DEFAULT = MC_1_21_2 };
 
 struct ExtGenConfig
 {
@@ -77,7 +78,7 @@ enum {
     LOPT_NOOCEAN_1,
     LOPT_BETA_T_1,
     LOPT_BETA_H_1,
-    LOPT_HEIGHT_4,
+    LOPT_HEIGHT,
     LOPT_STRUCTS,
     LOPT_MAX,
 };
diff --git a/src/formsearchcontrol.cpp b/src/formsearchcontrol.cpp
index 6e32bae..0605023 100644
--- a/src/formsearchcontrol.cpp
+++ b/src/formsearchcontrol.cpp
@@ -336,6 +336,17 @@ void FormSearchControl::setSearchRange(uint64_t smin, uint64_t smax)
     searchProgressReset();
 }
 
+bool FormSearchControl::getSeed(int row, uint64_t *seed)
+{
+    QAbstractItemModel *model = ui->results->model();
+    if (row < 0 || row >= model->rowCount())
+        return false;
+    QModelIndex idx = model->index(row, SeedTableModel::COL_SEED);
+    *seed = model->data(idx, Qt::UserRole).toULongLong();
+    return true;
+}
+
+
 void FormSearchControl::on_buttonClear_clicked()
 {
     model->reset();
@@ -444,13 +455,9 @@ void FormSearchControl::on_buttonMore_clicked()
 
 void FormSearchControl::onSeedSelectionChanged()
 {
-    int row = ui->results->currentIndex().row();
-    if (row >= 0 && row < ui->results->model()->rowCount())
-    {
-        QModelIndex idx = ui->results->model()->index(row, SeedTableModel::COL_SEED);
-        uint64_t s = ui->results->model()->data(idx, Qt::UserRole).toULongLong();
+    uint64_t s;
+    if (getSeed(ui->results->currentIndex().row(), &s))
         emit selectedSeedChanged(s);
-    }
 }
 
 void FormSearchControl::on_results_clicked(const QModelIndex &)
@@ -809,10 +816,9 @@ void FormSearchControl::removeCurrent()
 
 void FormSearchControl::copySeed()
 {
-    QModelIndex index = ui->results->currentIndex();
-    if (index.isValid())
+    uint64_t seed;
+    if (getSeed(ui->results->currentIndex().row(), &seed))
     {
-        uint64_t seed = ui->results->model()->data(index, Qt::UserRole).toULongLong();
         QClipboard *clipboard = QGuiApplication::clipboard();
         clipboard->setText(QString::asprintf("%" PRId64, seed));
     }
@@ -824,11 +830,10 @@ void FormSearchControl::copyResults()
     int n = ui->results->model()->rowCount();
     for (int i = 0; i < n; i++)
     {
-        QModelIndex idx = ui->results->model()->index(i, SeedTableModel::COL_SEED);
-        uint64_t seed = ui->results->model()->data(idx, Qt::UserRole).toULongLong();
-        text += QString::asprintf("%" PRId64 "\n", seed);
+        uint64_t seed;
+        if (getSeed(i, &seed))
+            text += QString::asprintf("%" PRId64 "\n", seed);
     }
-
     QClipboard *clipboard = QGuiApplication::clipboard();
     clipboard->setText(text);
 }
diff --git a/src/formsearchcontrol.h b/src/formsearchcontrol.h
index 13a3691..64338ce 100644
--- a/src/formsearchcontrol.h
+++ b/src/formsearchcontrol.h
@@ -114,6 +114,8 @@ public:
 
     void setSearchMode(int mode);
 
+    bool getSeed(int row, uint64_t *seed);
+
 signals:
     void selectedSeedChanged(uint64_t seed);
     void searchStatusChanged(bool running);
diff --git a/src/headless.cpp b/src/headless.cpp
index 914c727..aaf1f7b 100644
--- a/src/headless.cpp
+++ b/src/headless.cpp
@@ -5,8 +5,11 @@
 
 #include <QApplication>
 #include <QDateTime>
+#include <QFileInfo>
 #include <QStandardPaths>
 
+#include <stdio.h>
+
 #if defined(_WIN32)
 #include <windows.h>
 short get_term_width()
@@ -34,19 +37,20 @@ static QTextStream& qOut()
     return out;
 }
 
-Headless::Headless(QString sessionpath, QString resultspath, QObject *parent)
+Headless::Headless(QString sessionpath, QString resultspath, bool reset, QObject *parent)
     : QThread(parent)
     , sthread(nullptr)
     , sessionpath(sessionpath)
     , resultfile(resultspath)
     , resultstream(stdout)
+    , progressfp()
 {
     sthread.isdone = true;
 
     QSettings settings(APP_STRING, APP_STRING);
     g_extgen.load(settings);
 
-    if (!loadSession(sessionpath))
+    if (!loadSession(sessionpath, reset))
         return;
 
     if (!sthread.set(nullptr, session))
@@ -82,7 +86,7 @@ static bool load_seeds(std::vector<uint64_t>& seeds, QString path)
     return false;
 }
 
-bool Headless::loadSession(QString sessionpath)
+bool Headless::loadSession(QString sessionpath, bool reset)
 {
     qOut() << "Loading session: \"" << sessionpath << "\"\n";
     qOut().flush();
@@ -100,6 +104,11 @@ bool Headless::loadSession(QString sessionpath)
         return false;
     }
 
+    if (reset)
+        session.sc.startseed = 0;
+    else
+        results = session.slist;
+
     if (session.cv.empty())
     {
         warn(nullptr, "Session defines no search constraints.");
@@ -149,15 +158,32 @@ void Headless::run()
     session.writeHeader(resultstream);
     resultstream.flush();
 
-    sthread.startSearch();
-    elapsed.start();
-
     if (resultfile.isOpen())
     {
+        // open a separate write channel to the same result file and
+        // reserve space for a progress field after the header
+        QByteArray path = QFileInfo(resultfile).absoluteFilePath().toLocal8Bit();
+        progressfp = fopen(path.data(), "rb+");
+        if (progressfp)
+        {
+            fseek(progressfp, resultfile.size(), SEEK_SET);
+            resultstream << QString::asprintf("#Progress: %20" PRId64 "\n", session.sc.startseed);
+            resultstream.flush();
+        }
+
+        for (uint64_t s : results)
+        {
+            resultstream << (int64_t) s << "\n";
+            resultstream.flush();
+        }
+
         qOut() << "\n\n\n\n\n\n\n";
         qOut().flush();
         timer.start(250);
     }
+
+    sthread.startSearch();
+    elapsed.start();
 }
 
 void Headless::searchResult(uint64_t seed)
@@ -174,6 +200,11 @@ void Headless::searchFinish(bool done)
         timer.stop();
         progressTimeout();
     }
+    if (progressfp)
+    {
+        fclose(progressfp);
+        progressfp = NULL;
+    }
     if (done)
         qOut() << "Search done!\n";
     qOut() << "Stopping event loop.\n";
@@ -188,6 +219,13 @@ void Headless::progressTimeout()
     qreal min, avg, max;
     sthread.getProgress(&status, &prog, &end, &seed, &min, &avg, &max);
 
+    if (progressfp)
+    {
+        long pos = ftell(progressfp);
+        fprintf(progressfp, "#Progress: %20" PRId64 "\n", seed);
+        fseek(progressfp, pos, SEEK_SET);
+    }
+
     short width = get_term_width();
     if (width <= 24)
         return;
diff --git a/src/headless.h b/src/headless.h
index 40b5e6c..2b29a1a 100644
--- a/src/headless.h
+++ b/src/headless.h
@@ -12,10 +12,10 @@ class Headless : public QThread
     Q_OBJECT
 
 public:
-    Headless(QString sessionpath, QString resultspath, QObject *parent = 0);
+    Headless(QString sessionpath, QString resultspath, bool reset, QObject *parent = 0);
     virtual ~Headless();
 
-    bool loadSession(QString sessionpath);
+    bool loadSession(QString sessionpath, bool reset);
 
 public slots:
     void run();
@@ -33,6 +33,7 @@ public:
     std::vector<uint64_t> results;
     QFile resultfile;
     QTextStream resultstream;
+    FILE *progressfp;
     QTimer timer;
     QElapsedTimer elapsed;
 };
diff --git a/src/layerdialog.cpp b/src/layerdialog.cpp
index e507256..a794916 100644
--- a/src/layerdialog.cpp
+++ b/src/layerdialog.cpp
@@ -20,7 +20,7 @@ bool getLayerOptionInfo(LayerOptInfo *info, int mode, int disp, WorldInfo wi)
         if (disp == 3) txt = "1:64";
         if (disp == 4) txt = "1:256";
         break;
-    case LOPT_HEIGHT_4:
+    case LOPT_HEIGHT:
         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");
@@ -113,7 +113,7 @@ LayerDialog::LayerDialog(QWidget *parent, WorldInfo wi)
     radio[LOPT_NOOCEAN_1] = ui->radioNoOcean;
     radio[LOPT_BETA_T_1] = ui->radioBetaT;
     radio[LOPT_BETA_H_1] = ui->radioBetaH;
-    radio[LOPT_HEIGHT_4] = ui->radioHeight;
+    radio[LOPT_HEIGHT] = ui->radioHeight;
     radio[LOPT_STRUCTS] = ui->radioStruct;
 
     combo[LOPT_BIOMES] = ui->comboBiomes;
@@ -122,7 +122,7 @@ LayerDialog::LayerDialog(QWidget *parent, WorldInfo wi)
     combo[LOPT_NOISE_C_4] = ui->comboNoiseC;
     combo[LOPT_NOISE_E_4] = ui->comboNoiseE;
     combo[LOPT_NOISE_W_4] = ui->comboNoiseW;
-    combo[LOPT_HEIGHT_4] = ui->comboHeight;
+    combo[LOPT_HEIGHT] = ui->comboHeight;
 
     for (int i = 0; i < LOPT_MAX; i++)
     {
diff --git a/src/main.cpp b/src/main.cpp
index 31e6b54..b059251 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -34,6 +34,7 @@ int main(int argc, char *argv[])
 
     bool version = false;
     bool nogui = false;
+    bool clear = false;
     bool reset = false;
     bool usage = false;
     QString sessionpath;
@@ -45,6 +46,8 @@ int main(int argc, char *argv[])
             version = true;
         else if (strcmp(argv[i], "--nogui") == 0)
             nogui = true;
+        else if (strcmp(argv[i], "--reset") == 0)
+            clear = true;
         else if (strcmp(argv[i], "--reset-all") == 0)
             reset = true;
         else if (strncmp(argv[i], "--session=", 10) == 0)
@@ -67,6 +70,7 @@ int main(int argc, char *argv[])
                 "      --help                 Display this help and exit.\n"
                 "      --version              Output version information and exit.\n"
                 "      --nogui                Run in headless search mode.\n"
+                "      --reset                Discard results and reset starting seed.\n"
                 "      --reset-all            Clear settings and remove all session data.\n"
                 "      --session=file         Open this session file.\n"
                 "      --out=file             Write matching seeds to this file while searching.\n"
@@ -105,7 +109,7 @@ int main(int argc, char *argv[])
     if (nogui)
     {
         QCoreApplication app(argc, argv);
-        Headless headless(sessionpath, resultspath, &app);
+        Headless headless(sessionpath, resultspath, clear, &app);
 
         QObject::connect(&headless, SIGNAL(finished()), &app, SLOT(quit()));
         QTimer::singleShot(0, &headless, SLOT(run()));
diff --git a/src/mainwindow.cpp b/src/mainwindow.cpp
index cfcdf51..0af5343 100644
--- a/src/mainwindow.cpp
+++ b/src/mainwindow.cpp
@@ -111,7 +111,7 @@ MainWindow::MainWindow(QString sessionpath, QString resultspath, QWidget *parent
     laction[LOPT_NOOCEAN_1] = ui->actionNoOceans;
     laction[LOPT_BETA_T_1] = ui->actionBetaTemperature;
     laction[LOPT_BETA_H_1] = ui->actionBetaHumidity;
-    laction[LOPT_HEIGHT_4] = ui->actionHeight;
+    laction[LOPT_HEIGHT] = ui->actionHeight;
     laction[LOPT_STRUCTS] = ui->actionStructures;
 
     QActionGroup *grp = new QActionGroup(this);
@@ -365,7 +365,7 @@ bool MainWindow::getSeed(WorldInfo *wi, bool applyrand)
     {
         if (applyrand)
             qDebug() << "Unknown MC version: " << mcs.c_str();
-        wi->mc = MC_NEWEST;
+        wi->mc = MC_DEFAULT;
         ok = false;
     }
 
@@ -697,13 +697,13 @@ void MainWindow::setMCList(bool experimental)
     if (ui->comboBoxMC->count())
         getSeed(&wi, false);
     else
-        wi.mc = MC_NEWEST;
+        wi.mc = MC_DEFAULT;
     QStringList mclist;
     for (int mc = MC_NEWEST; mc > MC_UNDEF; mc--)
     {
         if (!experimental && mc != wi.mc)
         {
-            if (mc <= MC_1_0 || mc == MC_1_16_1 || mc == MC_1_19_2)
+            if (mc <= MC_1_0 || mc == MC_1_16_1 || mc == MC_1_19_2 || mc == MC_1_21_3)
                 continue;
         }
         const char *mcs = mc2str(mc);
diff --git a/src/mapview.cpp b/src/mapview.cpp
index 5ac7bed..f76d919 100644
--- a/src/mapview.cpp
+++ b/src/mapview.cpp
@@ -502,7 +502,7 @@ 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;
-        Pos p = {(int)clampimax(bx), (int)clampimax(bz)};
+        Pos p = {(int)clampimax(floor(bx)), (int)clampimax(floor(bz))};
         overlay->pos = p;
         overlay->bname = world->getBiomeName(p);
 
diff --git a/src/search.cpp b/src/search.cpp
index 0f830fe..effbdbf 100644
--- a/src/search.cpp
+++ b/src/search.cpp
@@ -1275,6 +1275,7 @@ L_qm_any:
     case F_PORTALN:
     case F_ANCIENT_CITY:
     case F_TRAILS:
+    case F_CHAMBERS:
 
     case F_FORTRESS:
     case F_BASTION:
diff --git a/src/search.h b/src/search.h
index d0c9f77..084e331 100644
--- a/src/search.h
+++ b/src/search.h
@@ -91,6 +91,7 @@ enum
     F_TRAILS,
     F_BIOME_SAMPLE,
     F_NOISE_SAMPLE,
+    F_CHAMBERS,
     // new filters should be added here at the end to keep some downwards compatibility
     FILTER_MAX,
 };
@@ -504,6 +505,13 @@ static const struct FilterList : private FilterInfo
             ""
         };
 
+        list[F_CHAMBERS] = FilterInfo{
+            CAT_STRUCT, 1, LOC_RAD, Trial_Chambers, 1, BR_CLUST, MC_1_21, MC_NEWEST, 0, 0, disp++,
+            "chambers",
+            QT_TRANSLATE_NOOP("Filter", "Trial chambers"),
+            ""
+        };
+
         list[F_PORTAL] = FilterInfo{
             CAT_STRUCT, 0, LOC_RAD, Ruined_Portal, 1, BR_CLUST, MC_1_16_1, MC_NEWEST, 0, 0, disp++,
             "portal",
diff --git a/src/util.cpp b/src/util.cpp
index bb08dc5..3bdc7b6 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -156,6 +156,8 @@ QString getBiomeDisplay(int mc, int id)
     case mangrove_swamp:                return QApplication::translate("Biome", "Mangrove Swamp");
     // 1.20
     case cherry_grove:                  return QApplication::translate("Biome", "Cherry Grove");
+    // 1.21.3 (Winter Drop Version TBA)
+    case pale_garden:                   return QApplication::translate("Biome", "Pale Garden");
     }
     const char *name = biome2str(mc, id);
     return name ? name : "";
diff --git a/src/world.cpp b/src/world.cpp
index 418cb47..90b06e5 100644
--- a/src/world.cpp
+++ b/src/world.cpp
@@ -136,7 +136,7 @@ QStringList VarPos::detail() const
 
 
 Quad::Quad(const Level* l, int64_t i, int64_t j)
-    : wi(l->wi),dim(l->dim),lopt(l->lopt),g(&l->g),sn(&l->sn),hd(l->hd),scale(l->scale)
+    : wi(l->wi),dim(l->dim),lopt(l->lopt),g(&l->g),sn(&l->sn),highres(l->highres),scale(l->scale)
     , ti(i),tj(j),blocks(l->blocks),pixs(l->pixs),sopt(l->sopt)
     , biomes(),rgb(),img(),spos()
 {
@@ -267,7 +267,12 @@ void applyHeightShading(unsigned char *rgb, Range r,
         pw += 2*bd; ph += 2*bd;
     }
     std::vector<float> buf(pw * ph);
-    if (ps == 0)
+    if (ps == 0 && r.scale <= 8 && g->dim == DIM_END)
+    {
+        mapEndSurfaceHeight(&buf[0], &g->en, sn, px, pz, pw, ph, r.scale, 0);
+        mapEndIslandHeight(&buf[0], &g->en, g->seed, px, pz, pw, ph, r.scale);
+    }
+    else if (ps == 0 && r.scale == 4)
     {
         mapApproxHeight(&buf[0], 0, g, sn, px, pz, pw, ph);
     }
@@ -286,6 +291,7 @@ void applyHeightShading(unsigned char *rgb, Range r,
             }
         }
     }
+
     // interpolate height
     std::vector<float> height((w+2) * (h+2));
     for (int j = 0; j < h+2; j++)
@@ -382,7 +388,8 @@ void Quad::run()
 
     if (pixs > 0)
     {
-        if (lopt.mode == LOPT_STRUCTS && dim == DIM_OVERWORLD)
+        if ((lopt.mode == LOPT_STRUCTS && dim == DIM_OVERWORLD) ||
+            (g->mc <= MC_1_17 && scale > 256 && dim == DIM_OVERWORLD))
         {
             img = new QImage();
             done = true;
@@ -431,9 +438,13 @@ void Quad::run()
             g_mutex.unlock();
             biomesToImage(rgb, g_biomeColors, biomes, w, h, 1, 1);
 
-            if (lopt.mode == LOPT_HEIGHT_4)
+            if (lopt.mode == LOPT_HEIGHT)
             {
-                int stepbits = (hd ? 0 : 2);
+                int stepbits = 0; // interpolated_step = (1 << stepbits)
+                if (scale > 16)
+                {
+                    stepbits = 1;
+                }
                 applyHeightShading(rgb, r, g, sn, stepbits, lopt.disp[lopt.mode], false, isdel);
             }
         }
@@ -459,7 +470,7 @@ void Quad::run()
 Level::Level()
     : cells(),g(),sn(),entry(),lopt(),wi(),dim()
     , tx(),tz(),tw(),th()
-    , hd(),scale(),blocks(),pixs()
+    , highres(),scale(),blocks(),pixs()
     , sopt()
 {
 }
@@ -480,7 +491,7 @@ void Level::init4map(QWorld *w, int pix, int layerscale)
 
     tx = tz = tw = th = 0;
 
-    hd = (layerscale == 1);
+    highres = (layerscale == 1);
     scale = layerscale;
     pixs = pix;
     blocks = pix * layerscale;
@@ -504,7 +515,7 @@ void Level::init4map(QWorld *w, int pix, int layerscale)
     case LOPT_NOISE_E_4:
     case LOPT_NOISE_D_4:
     case LOPT_NOISE_W_4:
-    case LOPT_HEIGHT_4:
+    //case LOPT_HEIGHT_4:
     case LOPT_RIVER_4:
     case LOPT_STRUCTS:
         optlscale = 4;
@@ -796,7 +807,13 @@ void QWorld::setDim(int dim, LayerOpt lopt)
     initSurfaceNoise(&sn, dim, g.seed);
 
     int pixs, lcnt;
-    if (g.mc >= MC_1_18 || dim != DIM_OVERWORLD)
+    if (lopt.mode == LOPT_HEIGHT)
+    {
+        pixs = 32;
+        lcnt = 6;
+        qual = 4.0;
+    }
+    else if (g.mc > MC_1_17 || dim != DIM_OVERWORLD)
     {
         pixs = 128;
         lcnt = 6;
@@ -873,7 +890,7 @@ QString QWorld::getBiomeName(Pos p)
         return c + "=" + QString::number(id);
     }
     QString ret = getBiomeDisplay(wi.mc, id);
-    if (lopt.mode == LOPT_HEIGHT_4)
+    if (lopt.mode == LOPT_HEIGHT)
     {
         int y = estimateSurface(p);
         if (y > 0)
@@ -885,7 +902,15 @@ QString QWorld::getBiomeName(Pos p)
 int QWorld::estimateSurface(Pos p)
 {
     float y = 0;
-    mapApproxHeight(&y, 0, &g, &sn, p.x>>2, p.z>>2, 1, 1);
+    if (g.dim == DIM_END)
+    {   // use end surface generator for 1:1 scale
+        mapEndSurfaceHeight(&y, &g.en, &sn, p.x, p.z, 1, 1, 1, 0);
+        mapEndIslandHeight(&y, &g.en, g.seed, p.x, p.z, 1, 1, 1);
+    }
+    else
+    {
+        mapApproxHeight(&y, 0, &g, &sn, p.x>>2, p.z>>2, 1, 1);
+    }
     return (int) floor(y);
 }
 
@@ -1094,9 +1119,9 @@ struct SpawnStronghold : public Scheduled
     }
 };
 
-static bool draw_grid_rec(QPainter& painter, QRect &rec, qreal pix, int64_t x, int64_t z)
+static bool draw_grid_rec(QPainter& painter, QColor col, QRect &rec, qreal pix, int64_t x, int64_t z)
 {
-    painter.setPen(QPen(QColor(0, 0, 0, 96), 1));
+    painter.setPen(QPen(col, 1));
     painter.drawRect(rec);
     if (pix < 50)
         return false;
@@ -1142,6 +1167,7 @@ void QWorld::draw(QPainter& painter, int vw, int vh, qreal focusx, qreal focusz,
     smallfont.setPointSize(oldfont.pointSize() - 2);
     painter.setFont(smallfont);
 
+    QColor gridcol = lopt.mode == LOPT_HEIGHT ? QColor(192, 0, 0, 96) : QColor(0, 0, 0, 96);
     int gridpix = 128;
     // 128px is approximately the size of:
     //gridpix = painter.fontMetrics().boundingRect("-30000000,-30000000").width();
@@ -1166,7 +1192,7 @@ void QWorld::draw(QPainter& painter, int vw, int vh, qreal focusx, qreal focusz,
 
             if (sshow[D_GRID] && !gridspacing)
             {
-                draw_grid_rec(painter, rec, ps, q->ti*q->blocks, q->tj*q->blocks);
+                draw_grid_rec(painter, gridcol, rec, ps, q->ti*q->blocks, q->tj*q->blocks);
             }
         }
     }
@@ -1190,7 +1216,7 @@ void QWorld::draw(QPainter& painter, int vw, int vh, qreal focusx, qreal focusz,
                         qreal px = vw/2.0 + (x+i) * ps - focusx * blocks2pix;
                         qreal pz = vh/2.0 + (z+j) * ps - focusz * blocks2pix;
                         QRect rec(px, pz, ps, ps);
-                        draw_grid_rec(painter, rec, ps, (x+i)*gs, (z+j)*gs);
+                        draw_grid_rec(painter, gridcol, rec, ps, (x+i)*gs, (z+j)*gs);
                     }
                 }
                 break;
@@ -1264,6 +1290,41 @@ void QWorld::draw(QPainter& painter, int vw, int vh, qreal focusx, qreal focusz,
         }
     }
 
+    if (showBB && sshow[D_GATEWAY] && dim == DIM_END && g.mc > MC_1_12)
+    {
+        if (endgates.empty())
+        {
+            endgates.resize(40);
+            getFixedEndGateways(g.mc, g.seed, &endgates[0]);
+            for (int i = 0; i < 20; i++)
+               endgates[20 + i] = getLinkedGatewayPos(&g.en, &sn, g.seed, endgates[i]);
+        }
+
+        for (int i = 0; i < 20; i++)
+        {
+            qreal xsrc = vw/2.0 + (0.5 + endgates[i].x - focusx) * blocks2pix;
+            qreal ysrc = vh/2.0 + (0.5 + endgates[i].z - focusz) * blocks2pix;
+            qreal xdst = vw/2.0 + (0.5 + endgates[i+20].x - focusx) * blocks2pix;
+            qreal ydst = vh/2.0 + (0.5 + endgates[i+20].z - focusz) * blocks2pix;
+
+            QPen pen = painter.pen();
+            painter.setPen(QPen(QColor(192, 0, 0, 160), i == 0 ? 1.5 : 0.5));
+            painter.drawLine(QPointF(xsrc,ysrc), QPointF(xdst,ydst));
+            painter.setPen(pen);
+
+            if (blocks2pix >= 1.0 && abs(xsrc) < vw && abs(ysrc) < vh)
+            {
+                QString s = QString::number(i+1);
+                QRect rec = painter.fontMetrics().boundingRect(s);
+                qreal dx = xsrc - xdst;
+                qreal dy = ysrc - ydst;
+                qreal df = rec.height() / sqrt(dx*dx + dy*dy);
+                rec.moveCenter(QPoint(xsrc + dx * df, ysrc + dy * df));
+                painter.drawText(rec, s);
+            }
+        }
+    }
+
     for (Shape& s : shapes)
     {
         if (s.dim != DIM_UNDEF && s.dim != dim)
diff --git a/src/world.h b/src/world.h
index ba31c48..aeefb79 100644
--- a/src/world.h
+++ b/src/world.h
@@ -64,7 +64,7 @@ struct Quad : public Scheduled
     LayerOpt lopt;
     const Generator *g;
     const SurfaceNoise *sn;
-    int hd;
+    int highres;
     int scale;
     int ti, tj;
     int blocks;
@@ -101,7 +101,7 @@ struct Level
     WorldInfo wi;
     int dim;
     int tx, tz, tw, th;
-    int hd;
+    int highres;
     int scale;
     int blocks;
     int pixs;
@@ -204,6 +204,7 @@ public:
     QAtomicPointer<Pos> spawn;
     QAtomicPointer<PosElement> strongholds;
     QAtomicPointer<QVector<QuadInfo>> qsinfo;
+    QVector<Pos> endgates;
     // isdel is a flag for the worker thread to stop
     std::atomic_bool isdel;