Blur: Don't hardcode dock border-radius

data/Application.css

@@ -5,7 +5,6 @@
 
 dock {
     background: alpha(@bg_color, 0.8);
-    border-radius: 9px;
     box-shadow:
         inset 0 -1px 0 0 alpha(@highlight_color, 0.4),
         inset 0 1px 0 0 alpha(@highlight_color, 0.6),
@@ -15,7 +14,13 @@ dock {
         0 1px 3px alpha(black, 0.2),
         0 3px 9px alpha(black, 0.3);
     opacity: 0.6;
-    padding: 9px;
+
+    border-radius: 9px;
+    /* This is required to correctly get border-radius
+     * If the size on startup is < border-radius * 2, the blur radius will be set incorrectly
+     */
+    min-width: 18px;
+    min-height: 18px;
 }
 
 .reduce-transparency dock {

src/MainWindow.vala

@@ -18,7 +18,6 @@ public class Dock.MainWindow : Gtk.ApplicationWindow {
 
     // Matches top margin in Launcher.css
     private const int TOP_MARGIN = 64;
-    private const int BORDER_RADIUS = 9;
 
     private Settings transparency_settings;
     private static Settings settings = new Settings ("io.elementary.dock");
@@ -31,6 +30,7 @@ public class Dock.MainWindow : Gtk.ApplicationWindow {
     private WindowDragManager window_drag_manager;
     private BottomMargin bottom_margin;
     private bool initialized_blur = false;
+    private int border_radius = 0;
 
     class construct {
         set_css_name ("dock-window");
@@ -144,10 +144,19 @@ public class Dock.MainWindow : Gtk.ApplicationWindow {
             Graphene.Rect bounds;
             bottom_margin.compute_bounds (bottom_margin, out bounds);
 
+            var new_snapshot = new Gtk.Snapshot ();
+            snapshot (new_snapshot);
+
+            var widget_border_radius = RenderNodeWalker.get_first_border_radius (new_snapshot.free_to_node (), null);
+
+            if (widget_border_radius != null) {
+                border_radius = widget_border_radius;
+            }
+
             initialized_blur = true;
 
             if (panel != null) {
-                panel.add_blur (0, 0, 0, (int) bounds.get_height (), BORDER_RADIUS);
+                panel.add_blur (0, 0, 0, (int) bounds.get_height (), border_radius);
             } else {
                 update_panel_x11 ();
             }
@@ -185,7 +194,7 @@ public class Dock.MainWindow : Gtk.ApplicationWindow {
             if (initialized_blur) {
                 Graphene.Rect bounds;
                 bottom_margin.compute_bounds (bottom_margin, out bounds);
-                value += ":blur=0,0,0,%d,%d".printf ((int) bounds.get_height (), BORDER_RADIUS);
+                value += ":blur=0,0,0,%d,%d".printf ((int) bounds.get_height (), border_radius);
             }
 
             xdisplay.change_property (window, prop, X.XA_STRING, 8, 0, (uchar[]) value, value.length);

src/RenderNodeWalker.vala

@@ -0,0 +1,207 @@
+/*
+ * SPDX-License-Identifier: GPL-3.0
+ * SPDX-FileCopyrightText: 2025 elementary, Inc. (https://elementary.io)
+ */
+
+public class Dock.RenderNodeWalker : GLib.Object {
+    public static int? get_first_border_radius (Gsk.RenderNode main_node, out int depth) {
+        depth = 0;
+
+        var main_node_type = main_node.get_node_type ();
+
+        if (main_node_type == Gsk.RenderNodeType.ROUNDED_CLIP_NODE) {
+            return (int) ((Gsk.RoundedClipNode) main_node).get_clip ().corner[0].width;
+        }
+
+        depth++;
+
+        if (main_node_type == Gsk.RenderNodeType.CONTAINER_NODE) {
+            var container_node = (Gsk.ContainerNode) main_node;
+
+            var min_child_depth = int.MAX;
+            int? min_border_radius = null;
+
+            for (var i = 0; i < container_node.get_n_children (); i++) {
+                var child_node = container_node.get_child (i);
+
+                int child_depth;
+                var border_radius = get_first_border_radius (child_node, out child_depth);
+
+                if (child_depth < min_child_depth && border_radius != null) {
+                    min_child_depth = child_depth;
+                    min_border_radius = border_radius;
+                }
+            }
+
+            depth += min_child_depth;
+            return min_border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.GL_SHADER_NODE) {
+            var gl_shader_node = (Gsk.GLShaderNode) main_node;
+
+            var min_child_depth = int.MAX;
+            int? min_border_radius = null;
+
+            for (var i = 0; i < gl_shader_node.get_n_children (); i++) {
+                var child_node = gl_shader_node.get_child (i);
+
+                int child_depth;
+                var border_radius = get_first_border_radius (child_node, out child_depth);
+
+                if (child_depth < min_child_depth && border_radius != null) {
+                    min_child_depth = child_depth;
+                    min_border_radius = border_radius;
+                }
+            }
+
+            depth += min_child_depth;
+            return min_border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.TRANSFORM_NODE) {
+            var child_node = ((Gsk.TransformNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.OPACITY_NODE) {
+            var child_node = ((Gsk.OpacityNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.COLOR_MATRIX_NODE) {
+            var child_node = ((Gsk.ColorMatrixNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.REPEAT_NODE) {
+            var child_node = ((Gsk.RepeatNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.CLIP_NODE) {
+            var child_node = ((Gsk.ClipNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.SHADOW_NODE) {
+            var child_node = ((Gsk.ShadowNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.BLUR_NODE) {
+            var child_node = ((Gsk.BlurNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.DEBUG_NODE) {
+            var child_node = ((Gsk.DebugNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.FILL_NODE) {
+            var child_node = ((Gsk.FillNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.STROKE_NODE) {
+            var child_node = ((Gsk.StrokeNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        if (main_node_type == Gsk.RenderNodeType.SUBSURFACE_NODE) {
+            var child_node = ((Gsk.SubsurfaceNode) main_node).get_child ();
+
+            int child_depth;
+            var border_radius = get_first_border_radius (child_node, out child_depth);
+
+            if (border_radius != null) {
+                depth += child_depth;
+            }
+
+            return border_radius;
+        }
+
+        return null;
+    }
+}

src/meson.build

@@ -4,6 +4,7 @@ sources = [
     'BaseItem.vala',
     'ItemManager.vala',
     'MainWindow.vala',
+    'RenderNodeWalker.vala',
     'AppSystem' / 'App.vala',
     'AppSystem' / 'AppSystem.vala',
     'AppSystem' / 'Launcher.vala',