Revert "fix glyph-overhang artifacts in partial row repaint"

This reverts commit 57103bb98b.

.classpath

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<classpath>
+	<classpathentry kind="src" output="bin/main" path="src/main/java">
+		<attributes>
+			<attribute name="gradle_scope" value="main"/>
+			<attribute name="gradle_used_by_scope" value="main,test"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="src" output="bin/main" path="src/main/resources">
+		<attributes>
+			<attribute name="gradle_scope" value="main"/>
+			<attribute name="gradle_used_by_scope" value="main,test"/>
+		</attributes>
+	</classpathentry>
+	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER/org.eclipse.jdt.internal.debug.ui.launcher.StandardVMType/JavaSE-21/"/>
+	<classpathentry kind="con" path="org.eclipse.buildship.core.gradleclasspathcontainer"/>
+	<classpathentry kind="output" path="bin/default"/>
+</classpath>

.codexsession

@@ -0,0 +1 @@
+019e6999-b7c8-7591-a8aa-ea51b89a7f7e

.gitignore

@@ -11,10 +11,6 @@ devenv.local.yaml
 # pre-commit
 .pre-commit-config.yaml
 build
+build
 .gradle
 bin
-.settings
-.project
-.worktrees
-.classpath
-.codexsession

.ignore

@@ -1,4 +1,3 @@
 .gradle
-bin
 result
-.worktrees
+bin

.project

@@ -0,0 +1,34 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+	<name>jprototerm</name>
+	<comment>Project jprototerm created by Buildship.</comment>
+	<projects>
+	</projects>
+	<buildSpec>
+		<buildCommand>
+			<name>org.eclipse.jdt.core.javabuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+		<buildCommand>
+			<name>org.eclipse.buildship.core.gradleprojectbuilder</name>
+			<arguments>
+			</arguments>
+		</buildCommand>
+	</buildSpec>
+	<natures>
+		<nature>org.eclipse.jdt.core.javanature</nature>
+		<nature>org.eclipse.buildship.core.gradleprojectnature</nature>
+	</natures>
+	<filteredResources>
+		<filter>
+			<id>1779917652126</id>
+			<name></name>
+			<type>30</type>
+			<matcher>
+				<id>org.eclipse.core.resources.regexFilterMatcher</id>
+				<arguments>node_modules|\.git|__CREATED_BY_JAVA_LANGUAGE_SERVER__</arguments>
+			</matcher>
+		</filter>
+	</filteredResources>
+</projectDescription>

.settings/org.eclipse.buildship.core.prefs

@@ -0,0 +1,13 @@
+arguments=--init-script /home/anon/Src/eclipse.jdt.ls/org.eclipse.jdt.ls.product/target/repository/configuration/org.eclipse.osgi/58/0/.cp/gradle/init/init.gradle
+auto.sync=false
+build.scans.enabled=false
+connection.gradle.distribution=GRADLE_DISTRIBUTION(LOCAL_INSTALLATION(/home/anon/.sdkman/candidates/gradle/current))
+connection.project.dir=
+eclipse.preferences.version=1
+gradle.user.home=
+java.home=/nix/store/c3pl7bqrx3d2rc3dh98z6yaj0mv1p52g-openjdk-21.0.10+7/lib/openjdk
+jvm.arguments=
+offline.mode=false
+override.workspace.settings=true
+show.console.view=true
+show.executions.view=true

README.md

@@ -106,7 +106,6 @@ navigate_up = "ALT+K"
 navigate_right = "ALT+L"
 toggle_floating = "ALT+F"
 new_pane = "ALT+N"
-next_floating = "ALT+F12"
 close_pane = "ALT+X"
 new_tab = "ALT+A"
 previous_tab = "ALT+SHIFT+H"
@@ -121,7 +120,6 @@ open_scrollback = "ALT+S"
 - `Alt+n`: new pane — a floating pane when floating panes are shown, otherwise a new tiled
   pane (tiled panes are split equally across the width)
 - `Alt+f`: show or hide all floating panes
-- `Alt+F12`: cycle floating panes
 - `Alt+x`: close the active pane; closing a tab's last pane closes the tab, and closing the
   last pane of the last tab quits
 - `Alt+a`: new tab

config.example.toml

@@ -25,8 +25,7 @@ navigate_down = "ALT+J"
 navigate_up = "ALT+K"
 navigate_right = "ALT+L"
 toggle_floating = "ALT+F"
-new_floating = "ALT+SHIFT+F"
+new_pane = "ALT+N"
-next_floating = "ALT+F12"
 close_pane = "ALT+X"
 open_font_selector = "ALT+T"
 open_scrollback = "ALT+S"

flake.lock

@@ -70,11 +70,11 @@
         "nixpkgs": "nixpkgs"
       },
       "locked": {
-        "lastModified": 1780272954,
+        "lastModified": 1780256181,
-        "narHash": "sha256-bVWY60iw8yPIu7I8FuRPf06T0H1TDvQDVUlzeHQs8UA=",
+        "narHash": "sha256-/saXdnYMbAMfP7u6USSqtNkBIgqZhU+CPr3F8tUQhHU=",
         "ref": "refs/heads/main",
-        "rev": "06a9d5d3ecf11c58f0e41214d1b59900e672dd3a",
+        "rev": "db5ee5d20daf8855de3a3b2fa9349eced70946f0",
-        "revCount": 24,
+        "revCount": 21,
         "type": "git",
         "url": "https://gitea.gregorlohaus.com/gregor/jlibghostty.git"
       },

src/main/java/com/gregor/jprototerm/AppConfig.java

@@ -37,7 +37,6 @@ public record AppConfig(
             "navigate_right",
             "toggle_floating",
             "new_pane",
-            "next_floating",
             "close_pane",
             "new_tab",
             "previous_tab",
@@ -96,7 +95,6 @@ public record AppConfig(
                         Map.entry("navigate_right", KeyBinding.parse("ALT+L")),
                         Map.entry("toggle_floating", KeyBinding.parse("ALT+F")),
                         Map.entry("new_pane", KeyBinding.parse("ALT+N")),
-                        Map.entry("next_floating", KeyBinding.parse("ALT+F12")),
                         Map.entry("close_pane", KeyBinding.parse("ALT+X")),
                         Map.entry("new_tab", KeyBinding.parse("ALT+A")),
                         Map.entry("previous_tab", KeyBinding.parse("ALT+SHIFT+H")),

src/main/java/com/gregor/jprototerm/Compositor.java

@@ -4,60 +4,52 @@ import dev.jlibghostty.KeyModifiers;
 import dev.jlibghostty.MouseButton;
 import dev.jlibghostty.MouseEncoderSize;
 import dev.jlibghostty.MouseInput;
-import javafx.geometry.VPos;
+import javafx.geometry.Pos;
-import javafx.scene.Node;
+import javafx.scene.Parent;
-import javafx.scene.canvas.Canvas;
+import javafx.scene.control.Label;
-import javafx.scene.canvas.GraphicsContext;
 import javafx.scene.input.InputEvent;
 import javafx.scene.input.MouseEvent;
 import javafx.scene.input.ScrollEvent;
 import javafx.scene.input.ScrollEvent.VerticalTextScrollUnits;
+import javafx.scene.layout.Background;
+import javafx.scene.layout.BackgroundFill;
+import javafx.scene.layout.CornerRadii;
+import javafx.scene.layout.HBox;
+import javafx.scene.layout.Pane;
 import javafx.scene.paint.Color;
-import javafx.scene.text.Font;
-import javafx.scene.text.FontSmoothingType;
-import javafx.scene.text.TextAlignment;
 
 import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Objects;
+import java.util.Set;
 
 /**
- * Owns the window's tabs and drives rendering and input. It composites only the current tab:
+ * Owns the window's tabs and exposes the terminal surface as a JavaFX scene graph. Each
- * each frame it lays that tab out, paints the panes bottom-to-top (so the active floating pane
+ * terminal pane is mounted as its own node, so JavaFX child order handles stacking and clipping
- * lands on top) and lets each pane paint its own content, clipped to the region the layout gave
+ * between panes. The pane model still owns terminals, ptys, cell geometry, and snapshots; this
- * it. The cross-pane concerns live here — the dirty-frame bookkeeping, the tab strip, routing
+ * class handles tab/pane lifecycle, layout, focus, mouse routing, and frame scheduling.
- * mouse/scroll to the pane under the pointer, and the tab/pane lifecycle that {@link Main}'s key
- * bindings invoke.
  */
 public final class Compositor {
-    // Canvas background shown wherever no pane covers (gaps). Painted on a full recomposite.
     private static final Color GAP_BACKGROUND = Color.rgb(16, 16, 18);
     private static final Color TAB_TEXT = Color.rgb(225, 229, 235);
-    // Thin tab strip shown at the top when more than one tab is open.
+    private static final Color TAB_INACTIVE_TEXT = Color.rgb(128, 136, 148);
+    private static final Color TAB_ACTIVE_BACKGROUND = Color.rgb(45, 55, 72);
+    private static final Color TAB_INACTIVE_BACKGROUND = Color.rgb(22, 24, 28);
     private static final double TAB_BAR_HEIGHT = 22.0;
 
-    private final Canvas canvas = new Canvas();
+    private final Pane root = new Pane();
-    // Kitty images are drawn as retained nodes layered over the canvas, not composited onto it.
+    private final Pane paneLayer = new Pane();
-    private final KittyImageOverlay imageOverlay = new KittyImageOverlay();
+    private final HBox tabBar = new HBox(1.0);
     private final AppConfig config;
     private final TerminalMetrics metrics;
     private final List<Tab> tabs = new ArrayList<>();
+    private final Map<TerminalPane, TerminalPaneNode> nodes = new HashMap<>();
     private int currentTabIndex;
-    // Bumped on any structural change (tab switch, pane add/close/focus/move) so render()
+    private boolean sceneDirty = true;
-    // knows to recomposite. Terminal *content* changes are tracked separately through each
-    // tab's content version.
-    private long layoutVersion;
-    // Last content version drawn to the canvas per pane, so a content frame repaints only
-    // the panes that actually changed.
-    private final Map<TerminalPane, Long> paneContentVersion = new HashMap<>();
-    // Cheap per-frame dirty signal: skip the whole render when none of these changed.
     private double lastWidth = -1.0;
     private double lastHeight = -1.0;
-    private String lastFontFamily;
-    private double lastFontSize = -1.0;
-    private long lastLayoutVersion = Long.MIN_VALUE;
     private long lastContentVersion = Long.MIN_VALUE;
     private boolean mouseButtonPressed;
     private MouseButton pressedButton = MouseButton.UNKNOWN;
@@ -66,27 +58,25 @@ public final class Compositor {
         this.config = config;
         this.metrics = metrics;
         tabs.add(new Tab(config, metrics));
-        canvas.setFocusTraversable(true);
+
-        canvas.setOnMousePressed(this::handleMousePressed);
+        root.setFocusTraversable(true);
-        canvas.setOnMouseReleased(this::handleMouseReleased);
+        root.setBackground(new Background(new BackgroundFill(GAP_BACKGROUND, CornerRadii.EMPTY, null)));
-        canvas.setOnMouseDragged(this::handleMouseDragged);
+        root.getChildren().setAll(paneLayer, tabBar);
-        canvas.setOnMouseMoved(this::handleMouseMoved);
+        root.setOnMousePressed(event -> root.requestFocus());
-        canvas.setOnScroll(this::handleScroll);
     }
 
-    public Canvas canvas() {
+    public Parent node() {
-        return canvas;
+        return root;
     }
 
-    /** The kitty-image overlay, to be stacked directly above {@link #canvas()} in the window. */
+    public void requestFocus() {
-    public Node imageOverlay() {
+        root.requestFocus();
-        return imageOverlay.node();
     }
 
     public void setFont(String family, double size) {
         metrics.setFont(family, size);
-        paneContentVersion.clear();
+        nodes.values().forEach(TerminalPaneNode::discard);
-        lastWidth = -1.0; // force a redraw on the next frame
+        markSceneDirty();
     }
 
     // ---- Tabs and panes -------------------------------------------------------------
@@ -101,7 +91,7 @@ public final class Compositor {
 
     public void navigate(Direction direction) {
         if (!isEmpty() && currentTab().navigate(direction)) {
-            layoutVersion++;
+            markSceneDirty();
         }
     }
 
@@ -110,7 +100,7 @@ public final class Compositor {
             return;
         }
         currentTab().toggleFloating();
-        layoutVersion++;
+        markSceneDirty();
     }
 
     public void createPane() {
@@ -118,25 +108,7 @@ public final class Compositor {
             return;
         }
         currentTab().createPane();
-        layoutVersion++;
+        markSceneDirty();
-    }
-
-    /** Opens a new floating pane, makes it active, and returns it (null when no tab exists). */
-    public TerminalPane openFloatingPane() {
-        if (isEmpty()) {
-            return null;
-        }
-        TerminalPane pane = currentTab().createFloatingPane();
-        layoutVersion++;
-        return pane;
-    }
-
-    public void nextFloatingPane() {
-        if (isEmpty()) {
-            return;
-        }
-        currentTab().nextFloatingPane();
-        layoutVersion++;
     }
 
     public void closeActivePane() {
@@ -145,33 +117,31 @@ public final class Compositor {
         }
         currentTab().closeActivePane();
         if (currentTab().isEmpty()) {
-            // Closing a tab's last pane closes the tab. When no tabs remain the surface is
-            // empty and Main quits.
             tabs.remove(currentTabIndex);
             if (currentTabIndex >= tabs.size()) {
                 currentTabIndex = Math.max(0, tabs.size() - 1);
             }
         }
-        layoutVersion++;
+        markSceneDirty();
     }
 
     public void newTab() {
         tabs.add(new Tab(config, metrics));
         currentTabIndex = tabs.size() - 1;
-        layoutVersion++;
+        markSceneDirty();
     }
 
     public void nextTab() {
         if (tabs.size() > 1) {
             currentTabIndex = (currentTabIndex + 1) % tabs.size();
-            layoutVersion++;
+            markSceneDirty();
         }
     }
 
     public void previousTab() {
         if (tabs.size() > 1) {
             currentTabIndex = (currentTabIndex - 1 + tabs.size()) % tabs.size();
-            layoutVersion++;
+            markSceneDirty();
         }
     }
 
@@ -180,6 +150,8 @@ public final class Compositor {
             tab.close();
         }
         tabs.clear();
+        nodes.clear();
+        paneLayer.getChildren().clear();
     }
 
     private Tab currentTab() {
@@ -190,143 +162,140 @@ public final class Compositor {
         return tabs.isEmpty() ? List.of() : currentTab().panes();
     }
 
+    private List<TerminalPane> allOpenPanes() {
+        List<TerminalPane> panes = new ArrayList<>();
+        for (Tab tab : tabs) {
+            panes.addAll(tab.allPanes());
+        }
+        return panes;
+    }
+
     private boolean isActive(TerminalPane pane) {
         return !tabs.isEmpty() && currentTab().isActive(pane);
     }
 
     private void focus(TerminalPane pane) {
         if (!tabs.isEmpty() && currentTab().focus(pane)) {
-            layoutVersion++;
+            markSceneDirty();
         }
     }
 
     // ---- Rendering ------------------------------------------------------------------
 
     public void render() {
-        switch (nextFrameType()) {
+        double width = root.getWidth();
-            case IDLE -> { }
+        double height = root.getHeight();
-            case LAYOUT -> renderLayoutFrame();
-            case CONTENT -> renderContentFrame();
-        }
-    }
-
-    // Classify this frame and commit the change trackers. A layout change (size, font,
-    // tab/pane set, z-order, active pane) needs a full recomposite; otherwise a change to the
-    // current tab's content version repaints only the panes that changed; otherwise nothing
-    // changed and the frame is idle.
-    private FrameType nextFrameType() {
-        double width = canvas.getWidth();
-        double height = canvas.getHeight();
         long contentVersion = tabs.isEmpty() ? 0 : currentTab().contentVersion();
-
+        boolean geometryChanged = width != lastWidth || height != lastHeight;
-        boolean layoutChanged = width != lastWidth || height != lastHeight
-                || metrics.fontSize() != lastFontSize || !Objects.equals(metrics.fontFamily(), lastFontFamily)
-                || layoutVersion != lastLayoutVersion;
         boolean contentChanged = contentVersion != lastContentVersion;
+        boolean syncScene = sceneDirty || geometryChanged;
+
+        if (!syncScene && !contentChanged) {
+            return;
+        }
 
         lastWidth = width;
         lastHeight = height;
-        lastFontFamily = metrics.fontFamily();
-        lastFontSize = metrics.fontSize();
-        lastLayoutVersion = layoutVersion;
         lastContentVersion = contentVersion;
-
+        sceneDirty = false;
-        if (layoutChanged) {
+        if (syncScene) {
-            return FrameType.LAYOUT;
+            syncSceneGraph(width, height);
         }
-        if (contentChanged) {
+        renderVisiblePanes();
-            return FrameType.CONTENT;
-        }
-        return FrameType.IDLE;
     }
 
-    // Full recomposite onto the retained canvas: lay the tab out, clear to the gap colour,
+    private void markSceneDirty() {
-    // draw the tab strip, then paint every pane bottom-to-top (panes() puts the active
+        sceneDirty = true;
-    // floating pane last == on top).
+    }
-    private void renderLayoutFrame() {
+
+    private void syncSceneGraph(double width, double height) {
         double topInset = tabs.size() > 1 ? TAB_BAR_HEIGHT : 0.0;
+
+        paneLayer.resizeRelocate(0.0, 0.0, width, height);
+        updateTabBar(width, topInset);
+
         if (!tabs.isEmpty()) {
-            currentTab().layout(canvas.getWidth(), canvas.getHeight(), topInset);
+            currentTab().layout(width, height, topInset);
         }
+
         List<TerminalPane> panes = currentPanes();
-        // Sync each pane's ghostty grid to its (possibly new) bounds; a no-op when unchanged.
+        retainNodes(allOpenPanes());
+        List<TerminalPaneNode> orderedNodes = new ArrayList<>(panes.size());
         for (TerminalPane pane : panes) {
             pane.fitToBounds();
+            TerminalPaneNode node = nodeFor(pane);
+            node.resizeRelocate(Math.round(pane.x()), Math.round(pane.y()), pane.width(), pane.height());
+            orderedNodes.add(node);
+        }
+        paneLayer.getChildren().setAll(orderedNodes);
     }
 
-        GraphicsContext gc = beginFrame();
+    private void renderVisiblePanes() {
-        paneContentVersion.keySet().retainAll(panes);
+        for (TerminalPane pane : currentPanes()) {
-        gc.setFill(GAP_BACKGROUND);
+            TerminalPaneNode node = nodes.get(pane);
-        gc.fillRect(0, 0, canvas.getWidth(), canvas.getHeight());
+            if (node != null) {
-        if (topInset > 0.0) {
+                node.renderIncremental(isActive(pane));
-            drawTabBar(gc, canvas.getWidth(), topInset);
             }
-        for (TerminalPane pane : panes) {
-            paneContentVersion.put(pane, pane.paintFull(gc, isActive(pane)));
-        }
-        imageOverlay.sync(panes);
-    }
-
-    // Repaint just the panes whose content changed, directly on the retained canvas. Each pane
-    // clips itself to its rect minus the panes above it, so a lower pane's repaint can't bleed
-    // over one stacked on top — no restore pass needed. Bounds and grids can't have changed
-    // without a layout frame, so a content frame reuses the existing layout untouched.
-    private void renderContentFrame() {
-        List<TerminalPane> panes = currentPanes();
-        GraphicsContext gc = beginFrame();
-
-        for (TerminalPane pane : panes) {
-            Long drawn = paneContentVersion.get(pane);
-            if (drawn != null && drawn == pane.contentVersion()) {
-                continue;
-            }
-            paneContentVersion.put(pane, pane.paintIncremental(gc, isActive(pane)));
-            imageOverlay.updatePane(pane);
         }
     }
 
-    private GraphicsContext beginFrame() {
+    private TerminalPaneNode nodeFor(TerminalPane pane) {
-        GraphicsContext gc = canvas.getGraphicsContext2D();
+        return nodes.computeIfAbsent(pane, this::createNode);
-        gc.setFontSmoothingType(FontSmoothingType.LCD); // the per-cell renderer relies on LCD
-        return gc;
     }
 
-    // Thin tab strip: one equal-width segment per tab, the current one highlighted, with a
+    private TerminalPaneNode createNode(TerminalPane pane) {
-    // small 1-based number centred in each segment.
+        TerminalPaneNode node = new TerminalPaneNode(pane, metrics);
-    private void drawTabBar(GraphicsContext gc, double width, double barHeight) {
+        node.setOnMousePressed(event -> handleMousePressed(pane, event));
-        int count = tabs.size();
+        node.setOnMouseReleased(event -> handleMouseReleased(pane, event));
-        Font barFont = Font.font(metrics.fontFamily(), Math.max(9.0, Math.min(13.0, barHeight * 0.62)));
+        node.setOnMouseDragged(event -> handleMouseDragged(pane, event));
-        gc.setFont(barFont);
+        node.setOnMouseMoved(event -> handleMouseMoved(pane, event));
-        gc.setFontSmoothingType(FontSmoothingType.GRAY);
+        node.setOnScroll(event -> handleScroll(pane, event));
-        gc.setTextAlign(TextAlignment.CENTER);
+        return node;
-        gc.setTextBaseline(VPos.CENTER);
+    }
 
-        double gap = 1.0;
+    private void retainNodes(List<TerminalPane> openPanes) {
-        double segmentWidth = width / count;
+        Set<TerminalPane> open = new HashSet<>(openPanes);
-        for (int i = 0; i < count; i++) {
+        nodes.keySet().removeIf(pane -> !open.contains(pane));
-            double x = i * segmentWidth;
+    }
+
+    private void updateTabBar(double width, double barHeight) {
+        tabBar.setVisible(barHeight > 0.0);
+        tabBar.setManaged(false);
+        tabBar.resizeRelocate(0.0, 0.0, width, barHeight);
+        tabBar.getChildren().clear();
+        if (barHeight <= 0.0) {
+            return;
+        }
+
+        double segmentWidth = width / tabs.size();
+        for (int i = 0; i < tabs.size(); i++) {
+            Label label = new Label(Integer.toString(i + 1));
             boolean current = i == currentTabIndex;
-            gc.setFill(current ? Color.rgb(45, 55, 72) : Color.rgb(22, 24, 28));
+            label.setAlignment(Pos.CENTER);
-            gc.fillRect(x, 0.0, segmentWidth - gap, barHeight);
+            label.setTextFill(current ? TAB_TEXT : TAB_INACTIVE_TEXT);
-            gc.setFill(current ? TAB_TEXT : Color.rgb(128, 136, 148));
+            label.setBackground(new Background(new BackgroundFill(
-            gc.fillText(Integer.toString(i + 1), x + (segmentWidth - gap) / 2.0, barHeight / 2.0);
+                    current ? TAB_ACTIVE_BACKGROUND : TAB_INACTIVE_BACKGROUND,
+                    CornerRadii.EMPTY,
+                    null)));
+            label.setFont(javafx.scene.text.Font.font(metrics.fontFamily(), Math.max(9.0, Math.min(13.0, barHeight * 0.62))));
+            label.setMinSize(0.0, barHeight);
+            label.setPrefSize(Math.max(0.0, segmentWidth - 1.0), barHeight);
+            label.setMaxSize(Double.MAX_VALUE, barHeight);
+            final int index = i;
+            label.setOnMousePressed(event -> {
+                currentTabIndex = index;
+                markSceneDirty();
+                root.requestFocus();
+                event.consume();
+            });
+            tabBar.getChildren().add(label);
         }
-
-        // Restore the defaults the cell renderer relies on (left-aligned, baseline, LCD).
-        gc.setTextAlign(TextAlignment.LEFT);
-        gc.setTextBaseline(VPos.BASELINE);
-        gc.setFontSmoothingType(FontSmoothingType.LCD);
     }
 
     // ---- Input ----------------------------------------------------------------------
 
-    private void handleMousePressed(MouseEvent event) {
+    private void handleMousePressed(TerminalPane pane, MouseEvent event) {
-        canvas.requestFocus();
+        root.requestFocus();
-        TerminalPane pane = paneAt(event.getX(), event.getY());
-        if (pane == null) {
-            return;
-        }
-
         focus(pane);
         pressedButton = mouseButton(event);
         mouseButtonPressed = true;
@@ -334,58 +303,38 @@ public final class Compositor {
         if (target == null) {
             return;
         }
-        send(pane, target, MouseInput.press(pressedButton, localX(event.getX(), pane, target), localY(event.getY(), pane, target), modifiers(event)), true, event);
+        send(pane, target, MouseInput.press(pressedButton, localX(event.getX(), target), localY(event.getY(), target), modifiers(event)), true, event);
-    }
-
-    private void handleMouseReleased(MouseEvent event) {
-        TerminalPane pane = paneAt(event.getX(), event.getY());
-        if (pane == null) {
-            pane = activePane();
     }
 
+    private void handleMouseReleased(TerminalPane pane, MouseEvent event) {
         MouseButton button = pressedButton == MouseButton.UNKNOWN ? mouseButton(event) : pressedButton;
         MouseTarget target = mouseTarget(pane);
         if (target != null) {
-            send(pane, target, MouseInput.release(button, localX(event.getX(), pane, target), localY(event.getY(), pane, target), modifiers(event)), false, event);
+            send(pane, target, MouseInput.release(button, localX(event.getX(), target), localY(event.getY(), target), modifiers(event)), false, event);
         }
         mouseButtonPressed = false;
         pressedButton = MouseButton.UNKNOWN;
     }
 
-    private void handleMouseDragged(MouseEvent event) {
+    private void handleMouseDragged(TerminalPane pane, MouseEvent event) {
-        TerminalPane pane = paneAt(event.getX(), event.getY());
-        if (pane == null) {
-            pane = activePane();
-        }
-
         MouseButton button = pressedButton == MouseButton.UNKNOWN ? mouseButton(event) : pressedButton;
         MouseTarget target = mouseTarget(pane);
         if (target == null) {
             return;
         }
-        send(pane, target, MouseInput.drag(button, localX(event.getX(), pane, target), localY(event.getY(), pane, target), modifiers(event)), true, event);
+        send(pane, target, MouseInput.drag(button, localX(event.getX(), target), localY(event.getY(), target), modifiers(event)), true, event);
-    }
-
-    private void handleMouseMoved(MouseEvent event) {
-        TerminalPane pane = paneAt(event.getX(), event.getY());
-        if (pane == null) {
-            return;
     }
 
+    private void handleMouseMoved(TerminalPane pane, MouseEvent event) {
         MouseTarget target = mouseTarget(pane);
         if (target == null) {
             return;
         }
-        send(pane, target, MouseInput.motion(localX(event.getX(), pane, target), localY(event.getY(), pane, target), modifiers(event)), mouseButtonPressed, event);
+        send(pane, target, MouseInput.motion(localX(event.getX(), target), localY(event.getY(), target), modifiers(event)), mouseButtonPressed, event);
     }
 
-    private void handleScroll(ScrollEvent event) {
+    private void handleScroll(TerminalPane pane, ScrollEvent event) {
-        TerminalPane pane = paneAt(event.getX(), event.getY());
+        root.requestFocus();
-        if (pane == null) {
-            return;
-        }
-
-        canvas.requestFocus();
         focus(pane);
         int direction = scrollDirection(event);
         if (direction == 0) {
@@ -397,9 +346,8 @@ public final class Compositor {
         MouseTarget target = mouseTarget(pane);
         boolean sent = false;
         if (target != null) {
-            // The wheel sends one button press per scrolled row; resolve the position once.
+            double ex = localX(event.getX(), target);
-            double ex = localX(event.getX(), pane, target);
+            double ey = localY(event.getY(), target);
-            double ey = localY(event.getY(), pane, target);
             KeyModifiers modifiers = modifiers(event);
             for (int i = 0; i < rows; i++) {
                 if (!send(pane, target, MouseInput.press(wheelButton, ex, ey, modifiers), mouseButtonPressed, event)) {
@@ -409,14 +357,11 @@ public final class Compositor {
             }
         }
         if (!sent) {
-            // Not consumed by the app (e.g. mouse reporting off): scroll the local viewport.
             pane.scrollViewport(direction > 0 ? -rows : rows);
             event.consume();
         }
     }
 
-    // Forward an already-positioned mouse event to the pane, consuming it if the pane (i.e.
-    // the app running in it) acted on it. Returns whether it was sent.
     private boolean send(TerminalPane pane, MouseTarget target, MouseInput input, boolean anyButtonPressed, InputEvent event) {
         boolean sent = pane.sendMouse(input, target.size(), anyButtonPressed);
         if (sent) {
@@ -425,17 +370,6 @@ public final class Compositor {
         return sent;
     }
 
-    private TerminalPane paneAt(double x, double y) {
-        List<TerminalPane> panes = currentPanes();
-        for (int i = panes.size() - 1; i >= 0; i--) {
-            TerminalPane pane = panes.get(i);
-            if (x >= pane.x() && x < pane.x() + pane.width() && y >= pane.y() && y < pane.y() + pane.height()) {
-                return pane;
-            }
-        }
-        return null;
-    }
-
     private MouseTarget mouseTarget(TerminalPane pane) {
         if (pane.width() <= 2 * TerminalMetrics.PADDING || pane.height() <= 2 * TerminalMetrics.PADDING) {
             return null;
@@ -450,14 +384,12 @@ public final class Compositor {
         return new MouseTarget(MouseEncoderSize.of(screenWidth, screenHeight, cellWidth, cellHeight), screenWidth, screenHeight);
     }
 
-    // Resolve a canvas-space pointer position to a pane-local pixel coordinate, clamped to
+    private static double localX(double nodeX, MouseTarget target) {
-    // the pane's reported screen size (what ghostty's mouse encoder expects).
+        return clamp(nodeX - TerminalMetrics.PADDING, 0.0, target.screenWidth() - 1.0);
-    private static double localX(double canvasX, TerminalPane pane, MouseTarget target) {
-        return clamp(canvasX - pane.x() - TerminalMetrics.PADDING, 0.0, target.screenWidth() - 1.0);
     }
 
-    private static double localY(double canvasY, TerminalPane pane, MouseTarget target) {
+    private static double localY(double nodeY, MouseTarget target) {
-        return clamp(canvasY - pane.y() - TerminalMetrics.PADDING, 0.0, target.screenHeight() - 1.0);
+        return clamp(nodeY - TerminalMetrics.PADDING, 0.0, target.screenHeight() - 1.0);
     }
 
     private static double clamp(double value, double min, double max) {
@@ -505,13 +437,6 @@ public final class Compositor {
         };
     }
 
-    // What one render() pass should do, decided from the change trackers in nextFrame().
-    private enum FrameType {
-        IDLE,     // nothing changed since the last frame
-        LAYOUT,   // geometry/font/tab/pane set changed: clear and repaint everything
-        CONTENT   // only terminal content changed: repaint the panes that changed
-    }
-
     private record MouseTarget(MouseEncoderSize size, long screenWidth, long screenHeight) {
     }
 }

src/main/java/com/gregor/jprototerm/KeyEncoder.java

@@ -26,7 +26,7 @@ final class KeyEncoder {
         return switch (code) {
             case ENTER -> "\r";
             case BACK_SPACE -> "\u007f";
-            case TAB -> event.isShiftDown() ? "\u001b[Z" : "\t";
+            case TAB -> "\t";
             case ESCAPE -> "\u001b";
             case UP -> "\u001b[A";
             case DOWN -> "\u001b[B";

src/main/java/com/gregor/jprototerm/KittyImageNode.java

@@ -1,32 +0,0 @@
-package com.gregor.jprototerm;
-
-import javafx.scene.image.Image;
-
-/**
- * A single kitty image to display, produced by the renderer and consumed by {@link
- * KittyImageOverlay}. Images are not painted onto the canvas; each becomes a retained
- * {@code ImageView} node positioned over the pane. The {@code source*} fields are the region of
- * {@link #image()} to show (in image pixels); the {@code x/y/width/height} are where to put it,
- * in scene coordinates (the same space the pane's clip {@code Shape} lives in).
- *
- * <p>{@code imageId}+{@code placementId} identify the placement so the overlay can reuse the
- * same node across frames instead of recreating it.
- */
-record KittyImageNode(
-        long imageId,
-        long placementId,
-        Image image,
-        double sourceX,
-        double sourceY,
-        double sourceWidth,
-        double sourceHeight,
-        double x,
-        double y,
-        double width,
-        double height
-) {
-    /** Stable per-pane key for node reuse. Packs the two u32 ids without collision. */
-    long key() {
-        return (imageId << 32) | (placementId & 0xffffffffL);
-    }
-}

src/main/java/com/gregor/jprototerm/KittyImageOverlay.java

@@ -1,151 +0,0 @@
-package com.gregor.jprototerm;
-
-import javafx.geometry.Rectangle2D;
-import javafx.scene.Group;
-import javafx.scene.Node;
-import javafx.scene.image.ImageView;
-import javafx.scene.layout.Pane;
-import javafx.scene.shape.Rectangle;
-import javafx.scene.shape.Shape;
-
-import java.util.ArrayList;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Iterator;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
-/**
- * Renders kitty graphics images as retained scene-graph nodes layered over the {@link Compositor}
- * canvas, instead of compositing them onto the canvas. Each pane gets a {@link Group} clipped to
- * that pane's region (the same clip {@code Shape} the canvas renderer uses), and each visible
- * image placement is an {@link ImageView} inside it, reused across frames so an unchanged image
- * costs nothing to redraw.
- *
- * <p>The overlay {@link #node()} is mouse-transparent and sits above the canvas in the window's
- * {@code StackPane}; its children use scene coordinates, which line up with the canvas because
- * both fill the same root.
- */
-final class KittyImageOverlay {
-    private final Pane root = new Pane();
-    private final Map<TerminalPane, PaneOverlay> overlays = new HashMap<>();
-
-    KittyImageOverlay() {
-        // Input belongs to the canvas underneath; the overlay only shows pixels.
-        root.setMouseTransparent(true);
-        root.setManaged(false);
-    }
-
-    Node node() {
-        return root;
-    }
-
-    /**
-     * Full reconcile to {@code panes} (bottom-to-top): drop overlays for panes that went away,
-     * refresh each surviving/added pane's images and clip, and order the per-pane groups to match
-     * the pane z-order. Called on layout frames, after the panes have painted.
-     */
-    void sync(List<TerminalPane> panes) {
-        Iterator<Map.Entry<TerminalPane, PaneOverlay>> it = overlays.entrySet().iterator();
-        while (it.hasNext()) {
-            Map.Entry<TerminalPane, PaneOverlay> entry = it.next();
-            if (!panes.contains(entry.getKey())) {
-                root.getChildren().remove(entry.getValue().group);
-                it.remove();
-            }
-        }
-        for (TerminalPane pane : panes) {
-            updatePane(pane);
-        }
-        // Only panes that actually have images get a group; order those to match pane z-order.
-        List<Node> ordered = new ArrayList<>(panes.size());
-        for (TerminalPane pane : panes) {
-            PaneOverlay overlay = overlays.get(pane);
-            if (overlay != null) {
-                ordered.add(overlay.group);
-            }
-        }
-        if (!root.getChildren().equals(ordered)) {
-            root.getChildren().setAll(ordered);
-        }
-    }
-
-    /**
-     * Refresh one pane's images and clip (called on content frames for each repainted pane).
-     * Creates the pane's group if this is the first time it has shown an image.
-     */
-    void updatePane(TerminalPane pane) {
-        List<KittyImageNode> images = pane.kittyImages();
-        PaneOverlay overlay = overlays.get(pane);
-        if (overlay == null) {
-            if (images.isEmpty()) {
-                return;
-            }
-            overlay = new PaneOverlay();
-            overlays.put(pane, overlay);
-            root.getChildren().add(overlay.group);
-        }
-        overlay.group.setClip(clipFor(pane));
-        reconcile(overlay, images);
-    }
-
-    private static void reconcile(PaneOverlay overlay, List<KittyImageNode> images) {
-        Set<Long> seen = new HashSet<>();
-        for (KittyImageNode node : images) {
-            long key = node.key();
-            seen.add(key);
-            ImageView view = overlay.views.get(key);
-            if (view == null) {
-                view = new ImageView();
-                view.setManaged(false);
-                view.setSmooth(true);
-                view.setPreserveRatio(false);
-                overlay.views.put(key, view);
-                overlay.group.getChildren().add(view);
-            }
-            apply(view, node);
-        }
-        if (overlay.views.size() == seen.size()) {
-            return;
-        }
-        Iterator<Map.Entry<Long, ImageView>> it = overlay.views.entrySet().iterator();
-        while (it.hasNext()) {
-            Map.Entry<Long, ImageView> entry = it.next();
-            if (!seen.contains(entry.getKey())) {
-                overlay.group.getChildren().remove(entry.getValue());
-                it.remove();
-            }
-        }
-    }
-
-    private static void apply(ImageView view, KittyImageNode node) {
-        if (view.getImage() != node.image()) {
-            view.setImage(node.image());
-        }
-        view.setViewport(new Rectangle2D(node.sourceX(), node.sourceY(), node.sourceWidth(), node.sourceHeight()));
-        view.setFitWidth(node.width());
-        view.setFitHeight(node.height());
-        view.setLayoutX(node.x());
-        view.setLayoutY(node.y());
-    }
-
-    // The pane's occlusion clip when one is set (rect minus covering panes), else the pane's
-    // plain bounds so an image can't spill outside its pane. Matches Tab's pixel snapping.
-    private static Shape clipFor(TerminalPane pane) {
-        Shape clip = pane.clip();
-        if (clip != null) {
-            return clip;
-        }
-        return new Rectangle(Math.round(pane.x()), Math.round(pane.y()), pane.width(), pane.height());
-    }
-
-    private static final class PaneOverlay {
-        private final Group group = new Group();
-        private final Map<Long, ImageView> views = new HashMap<>();
-
-        private PaneOverlay() {
-            group.setManaged(false);
-        }
-    }
-}

src/main/java/com/gregor/jprototerm/LinuxPty.java

@@ -97,7 +97,6 @@ public final class LinuxPty implements AutoCloseable {
 
     private final Arena arena = Arena.ofShared();
     private final MemorySegment readBuffer = arena.allocate(65536);
-    private final MemorySegment writeBuffer = arena.allocate(65536);
     private final Object writeLock = new Object();
     private final int masterFd;
     private final int pid;
@@ -187,20 +186,17 @@ public final class LinuxPty implements AutoCloseable {
             return;
         }
         synchronized (writeLock) {
-            int offset = 0;
+            try (Arena a = Arena.ofConfined()) {
+                MemorySegment buf = a.allocate(data.length);
+                MemorySegment.copy(data, 0, buf, ValueLayout.JAVA_BYTE, 0, data.length);
+                long offset = 0;
                 while (offset < data.length) {
-                int chunk = (int) Math.min(writeBuffer.byteSize(), data.length - offset);
+                    long n = callLong(WRITE, masterFd, buf.asSlice(offset), data.length - offset);
-                MemorySegment.copy(data, offset, writeBuffer, ValueLayout.JAVA_BYTE, 0, chunk);
+                    if (n < 0) {
-
-                long written = 0;
-                while (written < chunk) {
-                    long n = callLong(WRITE, masterFd, writeBuffer.asSlice(written), chunk - written);
-                    if (n <= 0) {
                         throw new IllegalStateException("write to pty failed");
                     }
-                    written += n;
+                    offset += n;
                 }
-                offset += chunk;
             }
         }
     }

src/main/java/com/gregor/jprototerm/Main.java

@@ -3,7 +3,6 @@ package com.gregor.jprototerm;
 import javafx.animation.AnimationTimer;
 import javafx.application.Application;
 import javafx.application.Platform;
-import javafx.geometry.Rectangle2D;
 import javafx.scene.Scene;
 import javafx.scene.control.ButtonType;
 import javafx.scene.control.ComboBox;
@@ -13,15 +12,12 @@ import javafx.scene.control.Spinner;
 import javafx.scene.control.SpinnerValueFactory;
 import javafx.scene.input.KeyEvent;
 import javafx.scene.layout.GridPane;
-import javafx.scene.layout.StackPane;
 import javafx.scene.text.Font;
-import javafx.stage.Screen;
 import javafx.stage.Stage;
 
 import java.io.IOException;
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.List;
 
 public final class Main extends Application {
     private Compositor compositor;
@@ -35,11 +31,7 @@ public final class Main extends Application {
         metrics = new TerminalMetrics(config.fontFamily(), config.fontSize());
         compositor = new Compositor(config, metrics);
 
-        StackPane root = new StackPane(compositor.canvas(), compositor.imageOverlay());
+        Scene scene = new Scene(compositor.node(), config.windowWidth(), config.windowHeight());
-        compositor.canvas().widthProperty().bind(root.widthProperty());
-        compositor.canvas().heightProperty().bind(root.heightProperty());
-
-        Scene scene = new Scene(root, config.windowWidth(), config.windowHeight());
         scene.addEventFilter(KeyEvent.KEY_PRESSED, this::handlePressed);
         scene.addEventFilter(KeyEvent.KEY_TYPED, event -> handleTyped(event));
 
@@ -55,37 +47,8 @@ public final class Main extends Application {
         stage.setOnCloseRequest(event -> {
             compositor.close();
         });
-        // JavaFX centres a new stage on the primary screen; on X11 there's no "focused monitor"
-        // to honour, so place it on the screen under the mouse pointer instead.
-        centreOnActiveScreen(stage, config.windowWidth(), config.windowHeight());
         stage.show();
-        compositor.canvas().requestFocus();
+        compositor.requestFocus();
-    }
-
-    // Centre the stage within the screen the mouse pointer is on (the best proxy for the
-    // "active" monitor on X11, which exposes no focused-monitor concept to JavaFX).
-    private static void centreOnActiveScreen(Stage stage, double width, double height) {
-        Rectangle2D bounds = activeScreen().getVisualBounds();
-        stage.setX(bounds.getMinX() + ((bounds.getWidth() - width) / 2.0));
-        stage.setY(bounds.getMinY() + ((bounds.getHeight() - height) / 2.0));
-    }
-
-    private static Screen activeScreen() {
-        try {
-            // AWT is the only way to read the pointer location before any window is shown;
-            // its coordinate space matches JavaFX's on the X11 virtual screen.
-            java.awt.PointerInfo pointer = java.awt.MouseInfo.getPointerInfo();
-            if (pointer != null) {
-                java.awt.Point at = pointer.getLocation();
-                List<Screen> screens = Screen.getScreensForRectangle(at.x, at.y, 1.0, 1.0);
-                if (!screens.isEmpty()) {
-                    return screens.get(0);
-                }
-            }
-        } catch (Throwable ignored) {
-            // Headless or AWT unavailable — fall back to the primary screen.
-        }
-        return Screen.getPrimary();
     }
 
     private void handlePressed(KeyEvent event) {
@@ -107,9 +70,6 @@ public final class Main extends Application {
         } else if (config.keybindings().get("new_pane").matches(event)) {
             compositor.createPane();
             event.consume();
-        } else if (config.keybindings().get("next_floating").matches(event)) {
-            compositor.nextFloatingPane();
-            event.consume();
         } else if (config.keybindings().get("close_pane").matches(event)) {
             compositor.closeActivePane();
             event.consume();
@@ -193,22 +153,17 @@ public final class Main extends Application {
                     config = config.withFont(selectedFamily.trim(), selectedSize);
                     config.save();
                     compositor.setFont(config.fontFamily(), config.fontSize());
-                    compositor.canvas().requestFocus();
+                    compositor.requestFocus();
                 });
     }
 
     private void openScrollbackInEditor() {
         try {
-            // Capture the active pane's scrollback before opening the floating pane, since that
-            // makes the new pane active.
             Path file = Files.createTempFile("jprototerm-scrollback-", ".txt");
             Files.writeString(file, compositor.activePane().scrollbackText());
             file.toFile().deleteOnExit();
 
-            TerminalPane pane = compositor.openFloatingPane();
+            compositor.activePane().send(scrollbackEditorCommand(file) + "\r");
-            if (pane != null) {
-                pane.send(scrollbackEditorCommand(file) + "\r");
-            }
         } catch (IOException ex) {
             System.err.println("Could not open scrollback in editor: " + ex.getMessage());
         }

src/main/java/com/gregor/jprototerm/RenderProfiler.java

@@ -0,0 +1,79 @@
+package com.gregor.jprototerm;
+
+/**
+ * Lightweight render profiler, disabled unless {@code -Djprototerm.profile=true} (or the
+ * {@code JPROTOTERM_PROFILE=1} environment variable) is set. It accumulates wall-clock nanos
+ * into a handful of buckets and prints aggregate per-frame stats to stderr every
+ * {@code jprototerm.profile.frames} render invocations (default 120).
+ *
+ * <p>All render work runs on the JavaFX application thread, so the accumulators are plain
+ * fields with no synchronization.
+ *
+ * <p>Caveat: JavaFX canvas drawing is deferred to the QuantumRenderer thread, so the
+ * {@link #DRAW} bucket measures only the cost of <em>recording</em> draw commands, not the
+ * GPU paint. Pair this with {@code -Djavafx.pulseLogger=true} to see the render-thread side.
+ */
+final class RenderProfiler {
+    static final int SNAPSHOT = 0;
+    static final int FINGERPRINT = 1;
+    static final int DRAW = 2;
+    static final int FRAME = 3;
+    static final int UPDATE = 4;
+    static final int MARSHAL = 5;
+    private static final int BUCKETS = 6;
+    private static final String[] NAMES =
+            {"snapshot", "fingerprint", "draw", "frame-total", "update", "marshal"};
+
+    private static final boolean ENABLED =
+            Boolean.getBoolean("jprototerm.profile") || "1".equals(System.getenv("JPROTOTERM_PROFILE"));
+    private static final int DUMP_FRAMES = Integer.getInteger("jprototerm.profile.frames", 120);
+
+    private static final long[] totalNanos = new long[BUCKETS];
+    private static final long[] counts = new long[BUCKETS];
+    private static int frames;
+
+    private RenderProfiler() {
+    }
+
+    static boolean enabled() {
+        return ENABLED;
+    }
+
+    /** Returns a start timestamp, or 0 when profiling is disabled. */
+    static long start() {
+        return ENABLED ? System.nanoTime() : 0L;
+    }
+
+    /** Records the time elapsed since {@code startNanos} into {@code bucket}. */
+    static void stop(int bucket, long startNanos) {
+        if (!ENABLED) {
+            return;
+        }
+        totalNanos[bucket] += System.nanoTime() - startNanos;
+        counts[bucket]++;
+    }
+
+    /** Marks the end of one render invocation; dumps and resets every {@code DUMP_FRAMES}. */
+    static void frame() {
+        if (!ENABLED) {
+            return;
+        }
+        if (++frames < DUMP_FRAMES) {
+            return;
+        }
+        dump();
+    }
+
+    private static void dump() {
+        StringBuilder sb = new StringBuilder(192);
+        sb.append("[render-profile] ").append(frames).append(" renders");
+        for (int i = 0; i < BUCKETS; i++) {
+            double totalMs = totalNanos[i] / 1_000_000.0;
+            sb.append(String.format(" | %s %.3fms/f (n=%d)", NAMES[i], totalMs / frames, counts[i]));
+            totalNanos[i] = 0;
+            counts[i] = 0;
+        }
+        System.err.println(sb);
+        frames = 0;
+    }
+}

src/main/java/com/gregor/jprototerm/RenderTarget.java

@@ -1,45 +0,0 @@
-package com.gregor.jprototerm;
-
-import dev.jlibghostty.KittyGraphics;
-import dev.jlibghostty.RenderStateSnapshot;
-import javafx.scene.shape.Shape;
-
-import java.util.Optional;
-
-/**
- * The read-only view of a pane that a {@link TerminalRenderer} draws: its on-screen rect, its
- * current render snapshot, and its kitty-graphics state. Decoupling the renderer from
- * {@link TerminalPane} through this interface lets the renderer be swapped (e.g. a debug
- * renderer that just outlines bounds and clip bands) and unit-tested against a synthetic
- * target without a real terminal.
- */
-interface RenderTarget {
-    double x();
-
-    double y();
-
-    double width();
-
-    double height();
-
-    /** Whether kitty graphics should be drawn for this target at all. */
-    boolean kittyEnabled();
-
-    Optional<KittyGraphics> kittyGraphics();
-
-    /**
-     * Incremental snapshot: only rows that changed since the last frame are populated. May be
-     * {@code null} before the first snapshot exists.
-     */
-    RenderStateSnapshot snapshot();
-
-    /** Full snapshot with every row populated, regardless of dirty state. */
-    RenderStateSnapshot snapshotFull();
-
-    /**
-     * The region this target may draw into, or {@code null} to clip to its plain rect. Set at
-     * layout time (a tiled pane gets its rect minus the floating panes that cover it), so the
-     * renderer can clip its own output and never paint over a pane on top.
-     */
-    Shape clip();
-}

src/main/java/com/gregor/jprototerm/Tab.java

@@ -1,12 +1,8 @@
 package com.gregor.jprototerm;
 
-import javafx.scene.shape.Rectangle;
-import javafx.scene.shape.Shape;
-
 import java.util.ArrayList;
 import java.util.Comparator;
 import java.util.List;
-import java.util.concurrent.atomic.AtomicLong;
 import java.util.stream.Stream;
 
 /**
@@ -34,7 +30,7 @@ final class Tab implements AutoCloseable {
     private double lastTopInset;
     // Bumped whenever one of this tab's panes changes content; the compositor reads the current
     // tab's value each frame as an O(1) "anything to repaint?" check.
-    private final AtomicLong contentVersion = new AtomicLong();
+    private long contentVersion;
 
     Tab(AppConfig config, TerminalMetrics metrics) {
         this.config = config;
@@ -55,7 +51,7 @@ final class Tab implements AutoCloseable {
     }
 
     long contentVersion() {
-        return contentVersion.get();
+        return contentVersion;
     }
 
     /**
@@ -79,6 +75,13 @@ final class Tab implements AutoCloseable {
         return List.copyOf(ordered);
     }
 
+    List<TerminalPane> allPanes() {
+        List<TerminalPane> all = new ArrayList<>(tiled.size() + floating.size());
+        all.addAll(tiled);
+        all.addAll(floating);
+        return List.copyOf(all);
+    }
+
     boolean isActive(TerminalPane pane) {
         return pane != null && pane == active;
     }
@@ -112,51 +115,6 @@ final class Tab implements AutoCloseable {
                     floatingWidth,
                     floatingHeight);
         }
-
-        assignClips();
-    }
-
-    // Give each pane its clip region for the next paints, so repainting a pane on a content
-    // frame can never bleed over one stacked on top of it. Each pane is clipped to its rect
-    // minus the union of the panes above it: floating panes are clipped by the floating panes
-    // higher in the stack, and tiled panes by the whole floating group. When nothing floats,
-    // every pane clips to its plain bounds.
-    private void assignClips() {
-        if (!floatingVisible || floating.isEmpty()) {
-            tiled.forEach(pane -> pane.setClip(null));
-            floating.forEach(pane -> pane.setClip(null));
-            return;
-        }
-
-        // Floating panes bottom-to-top, matching panes(): insertion order, active pane on top.
-        List<TerminalPane> order = new ArrayList<>(floating.size());
-        for (TerminalPane pane : floating) {
-            if (pane != active) {
-                order.add(pane);
-            }
-        }
-        if (floating.contains(active)) {
-            order.add(active);
-        }
-
-        // Walk top-to-bottom, accumulating the union of the panes above each one.
-        Shape above = null;
-        for (int i = order.size() - 1; i >= 0; i--) {
-            Rectangle rect = rectOf(order.get(i));
-            order.get(i).setClip(above == null ? null : Shape.subtract(rect, above));
-            above = (above == null) ? rect : Shape.union(above, rect);
-        }
-
-        // `above` is now the union of every floating pane; tiled panes sit under all of them.
-        for (TerminalPane pane : tiled) {
-            pane.setClip(Shape.subtract(rectOf(pane), above));
-        }
-    }
-
-    // Match the renderer's pixel snapping (round the origin, keep width/height) so the clip
-    // lines up exactly with where the floating panes are drawn.
-    private static Rectangle rectOf(TerminalPane pane) {
-        return new Rectangle(Math.round(pane.x()), Math.round(pane.y()), pane.width(), pane.height());
     }
 
     boolean navigate(Direction direction) {
@@ -202,16 +160,6 @@ final class Tab implements AutoCloseable {
         }
     }
 
-    void nextFloatingPane() {
-        if (floating.isEmpty()) {
-            createFloatingPane();
-            return;
-        }
-        floatingVisible = true;
-        int current = floating.indexOf(active); // -1 when the active pane is tiled
-        setActive(floating.get((current + 1 + floating.size()) % floating.size()));
-    }
-
     void closeActivePane() {
         TerminalPane closing = active;
         boolean wasFloating = floating.remove(closing);
@@ -257,12 +205,11 @@ final class Tab implements AutoCloseable {
         }
     }
 
-    TerminalPane createFloatingPane() {
+    private void createFloatingPane() {
         TerminalPane pane = openPane(true);
         floating.add(pane);
         floatingVisible = true;
         setActive(pane);
-        return pane;
     }
 
     private boolean navigateFloatingStack(Direction direction) {
@@ -293,7 +240,7 @@ final class Tab implements AutoCloseable {
     }
 
     private void markContentChanged() {
-        contentVersion.incrementAndGet();
+        contentVersion++;
     }
 
     private TerminalPane openPane(boolean asFloating) {

src/main/java/com/gregor/jprototerm/TerminalPane.java

@@ -12,36 +12,28 @@ import dev.jlibghostty.RenderStateSnapshot;
 import dev.jlibghostty.ScrollViewport;
 import dev.jlibghostty.Terminal;
 import dev.jlibghostty.TerminalOptions;
-import javafx.scene.canvas.GraphicsContext;
-import javafx.scene.shape.Shape;
 
 import java.util.Optional;
 import java.util.concurrent.atomic.AtomicLong;
 
 /**
  * One terminal: owns its ghostty {@link Terminal}, the {@link ShellSession}/pty driving it,
- * and its on-screen geometry and grid. It does not draw itself — it is a {@link RenderTarget}
+ * and its on-screen geometry and grid. It does not draw itself; {@link TerminalPaneNode}
- * that a {@link TerminalRenderer} paints. {@link #paintFull}/{@link #paintIncremental} are the
+ * reads snapshots from it and represents the visible rows and kitty graphics as JavaFX nodes.
- * only rendering API exposed to the {@link Compositor}, and they just delegate to that
- * renderer; the compositor decides z-order and which rect each pane occupies.
  */
-public final class TerminalPane implements AutoCloseable, RenderTarget {
+public final class TerminalPane implements AutoCloseable {
     private final Terminal terminal;
     private final TerminalMetrics metrics;
     private final boolean kittyEnabled;
     // Run on every content change so the owning tab can bump its content version — the
     // compositor's O(1) "did the current tab change?" gate.
     private final Runnable onContentChange;
-    private final TerminalRenderer renderer;
     private final MouseEncoder mouseEncoder = new MouseEncoder();
     // A persistent render state (reused across frames) is what makes ghostty's per-row dirty
     // tracking meaningful: update() accumulates dirty since the last resetDirty().
     private final RenderState renderState = new RenderState();
     private RenderStateSnapshot cachedSnapshot;
     private ShellSession session;
-    // Clip region for rendering (rect minus the panes covering this one), set at layout time;
-    // null means clip to the plain bounds. See RenderTarget#clip().
-    private Shape clip;
     private double x;
     private double y;
     private double width;
@@ -51,15 +43,14 @@ public final class TerminalPane implements AutoCloseable, RenderTarget {
     private int pixelWidth;
     private int pixelHeight;
     private final AtomicLong contentVersion = new AtomicLong();
-    private long snapshotVersion = -1;
+    private volatile long snapshotVersion = -1;
 
     private TerminalPane(Terminal terminal, TerminalMetrics metrics, boolean kittyEnabled,
-            Runnable onContentChange, TerminalRenderer renderer, int columns, int rows) {
+            Runnable onContentChange, int columns, int rows) {
         this.terminal = terminal;
         this.metrics = metrics;
         this.kittyEnabled = kittyEnabled;
         this.onContentChange = onContentChange;
-        this.renderer = renderer;
         this.columns = columns;
         this.rows = rows;
     }
@@ -76,8 +67,7 @@ public final class TerminalPane implements AutoCloseable, RenderTarget {
         int rows = heightPx > 0 ? metrics.rowsFor(heightPx) : config.rows();
         Terminal terminal = Ghostty.open(new TerminalOptions(columns, rows, config.maxScrollback()));
         terminal.setDeviceAttributesProvider(DeviceAttributes::xtermCompatible);
-        TerminalPane pane = new TerminalPane(terminal, metrics, config.kittyGraphics(), onContentChange,
+        TerminalPane pane = new TerminalPane(terminal, metrics, config.kittyGraphics(), onContentChange, columns, rows);
-                new GhosttyTerminalRenderer(metrics), columns, rows);
         pane.refresh();
         pane.attach(ShellSession.start(config.shell(), config.envOverride(), pane, columns, rows));
         return pane;
@@ -154,7 +144,6 @@ public final class TerminalPane implements AutoCloseable, RenderTarget {
      * Snapshotting is deferred here rather than done in refresh(), so a burst of writes
      * between two frames collapses into a single snapshot.
      */
-    @Override
     public RenderStateSnapshot snapshot() {
         return takeSnapshot(false);
     }
@@ -163,7 +152,6 @@ public final class TerminalPane implements AutoCloseable, RenderTarget {
      * Full snapshot with every row's cells populated. Used where the whole pane is redrawn
      * regardless of dirty state (the kitty-graphics path).
      */
-    @Override
     public RenderStateSnapshot snapshotFull() {
         return takeSnapshot(true);
     }
@@ -172,13 +160,21 @@ public final class TerminalPane implements AutoCloseable, RenderTarget {
         synchronized (terminal) {
             long version = contentVersion.get();
             if (full) {
+                long updateStart = RenderProfiler.start();
                 renderState.update(terminal);
+                RenderProfiler.stop(RenderProfiler.UPDATE, updateStart);
+                long marshalStart = RenderProfiler.start();
                 cachedSnapshot = renderState.snapshot();
+                RenderProfiler.stop(RenderProfiler.MARSHAL, marshalStart);
                 renderState.resetDirty();
                 snapshotVersion = version;
             } else if (snapshotVersion != version) {
+                long updateStart = RenderProfiler.start();
                 renderState.update(terminal);
+                RenderProfiler.stop(RenderProfiler.UPDATE, updateStart);
+                long marshalStart = RenderProfiler.start();
                 cachedSnapshot = renderState.snapshotIncremental();
+                RenderProfiler.stop(RenderProfiler.MARSHAL, marshalStart);
                 renderState.resetDirty();
                 snapshotVersion = version;
             }
@@ -197,34 +193,32 @@ public final class TerminalPane implements AutoCloseable, RenderTarget {
         return contentVersion.get();
     }
 
-    @Override
+    long snapshotVersion() {
+        return snapshotVersion;
+    }
+
     public boolean kittyEnabled() {
         return kittyEnabled;
     }
 
-    @Override
     public Optional<KittyGraphics> kittyGraphics() {
         synchronized (terminal) {
             return terminal.kittyGraphics();
         }
     }
 
-    @Override
     public double x() {
         return x;
     }
 
-    @Override
     public double y() {
         return y;
     }
 
-    @Override
     public double width() {
         return width;
     }
 
-    @Override
     public double height() {
         return height;
     }
@@ -236,16 +230,6 @@ public final class TerminalPane implements AutoCloseable, RenderTarget {
         this.height = height;
     }
 
-    /** Set the clip region applied on the next paints (see {@link RenderTarget#clip()}). */
-    public void setClip(Shape clip) {
-        this.clip = clip;
-    }
-
-    @Override
-    public Shape clip() {
-        return clip;
-    }
-
     /** Recompute the ghostty grid from the current bounds and the shared cell metrics. */
     public void fitToBounds() {
         int columns = metrics.columnsFor(width);
@@ -282,26 +266,6 @@ public final class TerminalPane implements AutoCloseable, RenderTarget {
         onContentChange.run();
     }
 
-    /** Paint the whole pane; see {@link TerminalRenderer#paintFull}. */
-    public long paintFull(GraphicsContext gc, boolean active) {
-        renderer.paintFull(gc, this, active);
-        return snapshotVersion;
-    }
-
-    /** Repaint what changed; see {@link TerminalRenderer#paintIncremental}. */
-    public long paintIncremental(GraphicsContext gc, boolean active) {
-        renderer.paintIncremental(gc, this, active);
-        return snapshotVersion;
-    }
-
-    /**
-     * Kitty image placements from the most recent paint, in scene coordinates. The compositor
-     * renders these as overlay nodes clipped to this pane (see {@link KittyImageOverlay}).
-     */
-    public java.util.List<KittyImageNode> kittyImages() {
-        return renderer.kittyImages();
-    }
-
     @Override
     public void close() {
         if (session != null) {

src/main/java/com/gregor/jprototerm/TerminalRenderer.java

@@ -1,68 +0,0 @@
-package com.gregor.jprototerm;
-
-import javafx.scene.canvas.GraphicsContext;
-import javafx.scene.shape.ClosePath;
-import javafx.scene.shape.LineTo;
-import javafx.scene.shape.MoveTo;
-import javafx.scene.shape.Path;
-import javafx.scene.shape.PathElement;
-import javafx.scene.shape.Shape;
-
-/**
- * Draws a {@link RenderTarget} onto a JavaFX canvas. The {@link Compositor} owns positioning
- * and z-order; a renderer only fills the target's rect, clipped to the target's {@link
- * RenderTarget#clip() clip region} so a repaint can never bleed over a pane on top.
- * Implementations can change the look entirely — {@link GhosttyTerminalRenderer} is the real
- * terminal renderer; a debug renderer could outline pane bounds instead.
- *
- * <p>A renderer may hold per-target state (e.g. a decoded-image cache), so an instance belongs
- * to a single {@link TerminalPane}.
- */
-abstract class TerminalRenderer {
-    /** Paint the whole target into its rect, clipped to its clip region. */
-    abstract void paintFull(GraphicsContext gc, RenderTarget target, boolean active);
-
-    /** Repaint only what changed since the last frame, clipped to the target's clip region. */
-    abstract void paintIncremental(GraphicsContext gc, RenderTarget target, boolean active);
-
-    /**
-     * The kitty image placements produced by the most recent paint, for the compositor to render
-     * as overlay nodes above the canvas. Empty unless the last paint found visible images.
-     */
-    java.util.List<KittyImageNode> kittyImages() {
-        return java.util.List.of();
-    }
-
-    protected static void clipRect(GraphicsContext gc, double x, double y, double width, double height) {
-        gc.beginPath();
-        gc.rect(x, y, width, height);
-        gc.clip();
-    }
-
-    /**
-     * Clip to {@code region} if given (the pane's rect minus the panes covering it, computed by
-     * {@code Shape.subtract} at layout), otherwise to the plain rect. The region is a rectilinear
-     * path, so it replays onto the canvas as move/line/close segments.
-     */
-    protected static void clip(GraphicsContext gc, double x, double y, double width, double height, Shape region) {
-        if (region == null) {
-            clipRect(gc, x, y, width, height);
-            return;
-        }
-        var elements = ((Path) region).getElements();
-        gc.beginPath();
-        if (elements.isEmpty()) {
-            gc.rect(x, y, 0.0, 0.0); // fully covered: clip to nothing
-        }
-        for (PathElement element : elements) {
-            if (element instanceof MoveTo moveTo) {
-                gc.moveTo(moveTo.getX(), moveTo.getY());
-            } else if (element instanceof LineTo lineTo) {
-                gc.lineTo(lineTo.getX(), lineTo.getY());
-            } else if (element instanceof ClosePath) {
-                gc.closePath();
-            }
-        }
-        gc.clip();
-    }
-}