XdgPopup: reimplement using the scene graph

xdg-shell version 3 is now implemented, supporting popup repositioning.

river/LayerSurface.zig

@@ -27,37 +27,42 @@ const util = @import("util.zig");
 
 const Output = @import("Output.zig");
 const SceneNodeData = @import("SceneNodeData.zig");
+const XdgPopup = @import("XdgPopup.zig");
 
 const log = std.log.scoped(.layer_shell);
 
 output: *Output,
 scene_layer_surface: *wlr.SceneLayerSurfaceV1,
+popup_tree: *wlr.SceneTree,
 
 destroy: wl.Listener(*wlr.LayerSurfaceV1) = wl.Listener(*wlr.LayerSurfaceV1).init(handleDestroy),
 map: wl.Listener(*wlr.LayerSurfaceV1) = wl.Listener(*wlr.LayerSurfaceV1).init(handleMap),
 unmap: wl.Listener(*wlr.LayerSurfaceV1) = wl.Listener(*wlr.LayerSurfaceV1).init(handleUnmap),
 commit: wl.Listener(*wlr.Surface) = wl.Listener(*wlr.Surface).init(handleCommit),
+new_popup: wl.Listener(*wlr.XdgPopup) = wl.Listener(*wlr.XdgPopup).init(handleNewPopup),
 
 pub fn create(wlr_layer_surface: *wlr.LayerSurfaceV1) error{OutOfMemory}!void {
     const output = @intToPtr(*Output, wlr_layer_surface.output.?.data);
     const layer_surface = try util.gpa.create(LayerSurface);
     errdefer util.gpa.destroy(layer_surface);
 
-    const tree = output.layerSurfaceTree(wlr_layer_surface.current.layer);
-    const scene_layer_surface = try tree.createSceneLayerSurfaceV1(wlr_layer_surface);
-
-    try SceneNodeData.attach(&scene_layer_surface.tree.node, .{ .layer_surface = layer_surface });
+    const layer_tree = output.layerSurfaceTree(wlr_layer_surface.current.layer);
 
     layer_surface.* = .{
         .output = output,
-        .scene_layer_surface = scene_layer_surface,
+        .scene_layer_surface = try layer_tree.createSceneLayerSurfaceV1(wlr_layer_surface),
+        .popup_tree = try output.layers.popups.createSceneTree(),
     };
     wlr_layer_surface.data = @ptrToInt(layer_surface);
 
+    try SceneNodeData.attach(&layer_surface.scene_layer_surface.tree.node, .{ .layer_surface = layer_surface });
+    try SceneNodeData.attach(&layer_surface.popup_tree.node, .{ .layer_surface = layer_surface });
+
     wlr_layer_surface.events.destroy.add(&layer_surface.destroy);
     wlr_layer_surface.events.map.add(&layer_surface.map);
     wlr_layer_surface.events.unmap.add(&layer_surface.unmap);
     wlr_layer_surface.surface.events.commit.add(&layer_surface.commit);
+    wlr_layer_surface.events.new_popup.add(&layer_surface.new_popup);
 
     // wlroots only informs us of the new surface after the first commit,
     // so our listener does not get called for this first commit. However,
@@ -65,6 +70,11 @@ pub fn create(wlr_layer_surface: *wlr.LayerSurfaceV1) error{OutOfMemory}!void {
     handleCommit(&layer_surface.commit, wlr_layer_surface.surface);
 }
 
+pub fn destroyPopups(layer_surface: *LayerSurface) void {
+    var it = layer_surface.scene_layer_surface.layer_surface.popups.safeIterator(.forward);
+    while (it.next()) |wlr_xdg_popup| wlr_xdg_popup.destroy();
+}
+
 fn handleDestroy(listener: *wl.Listener(*wlr.LayerSurfaceV1), wlr_layer_surface: *wlr.LayerSurfaceV1) void {
     const layer_surface = @fieldParentPtr(LayerSurface, "destroy", listener);
 
@@ -75,6 +85,8 @@ fn handleDestroy(listener: *wl.Listener(*wlr.LayerSurfaceV1), wlr_layer_surface:
     layer_surface.unmap.link.remove();
     layer_surface.commit.link.remove();
 
+    layer_surface.destroyPopups();
+
     util.gpa.destroy(layer_surface);
 }
 
@@ -163,3 +175,17 @@ fn handleKeyboardInteractiveExclusive(output: *Output) void {
         }
     }
 }
+
+fn handleNewPopup(listener: *wl.Listener(*wlr.XdgPopup), wlr_xdg_popup: *wlr.XdgPopup) void {
+    const layer_surface = @fieldParentPtr(LayerSurface, "new_popup", listener);
+
+    XdgPopup.create(
+        wlr_xdg_popup,
+        layer_surface.popup_tree,
+        layer_surface.popup_tree,
+        &layer_surface.output,
+    ) catch {
+        wlr_xdg_popup.resource.postNoMemory();
+        return;
+    };
+}

river/Output.zig

@@ -329,7 +329,12 @@ pub fn arrangeLayers(self: *Self) void {
         while (it.next()) |node| {
             assert(node.type == .tree);
             if (@intToPtr(?*SceneNodeData, node.data)) |node_data| {
-                node_data.data.layer_surface.scene_layer_surface.configure(&full_box, &usable_box);
+                const layer_surface = node_data.data.layer_surface;
+                layer_surface.scene_layer_surface.configure(&full_box, &usable_box);
+                layer_surface.popup_tree.node.setPosition(
+                    layer_surface.scene_layer_surface.tree.node.x,
+                    layer_surface.scene_layer_surface.tree.node.y,
+                );
             }
         }
     }

river/Seat.zig

@@ -241,8 +241,12 @@ pub fn setFocusRaw(self: *Self, new_focus: FocusTarget) void {
         .view => |view| {
             view.pending.focus -= 1;
             if (view.pending.focus == 0) view.setActivated(false);
+            view.destroyPopups();
         },
-        .xwayland_override_redirect, .layer, .lock_surface, .none => {},
+        .layer => |layer_surface| {
+            layer_surface.destroyPopups();
+        },
+        .xwayland_override_redirect, .lock_surface, .none => {},
     }
 
     // Set the new focus

river/Server.zig

@@ -100,7 +100,7 @@ pub fn init(self: *Self) !void {
     const compositor = try wlr.Compositor.create(self.wl_server, self.renderer);
     _ = try wlr.Subcompositor.create(self.wl_server);
 
-    self.xdg_shell = try wlr.XdgShell.create(self.wl_server, 2);
+    self.xdg_shell = try wlr.XdgShell.create(self.wl_server, 3);
     self.new_xdg_surface.setNotify(handleNewXdgSurface);
     self.xdg_shell.events.new_surface.add(&self.new_xdg_surface);
 

river/View.zig

@@ -84,6 +84,7 @@ borders: struct {
     top: *wlr.SceneRect,
     bottom: *wlr.SceneRect,
 },
+popup_tree: *wlr.SceneTree,
 
 /// This indicates that the view should be destroyed when the current
 /// transaction completes. See View.destroy()
@@ -126,8 +127,6 @@ pub fn init(self: *Self, output: *Output, tree: *wlr.SceneTree, impl: Impl) erro
         break :blk if (tags != 0) tags else output.current.tags;
     };
 
-    try SceneNodeData.attach(&tree.node, .{ .view = self });
-
     self.* = .{
         .impl = impl,
         .output = output,
@@ -138,9 +137,13 @@ pub fn init(self: *Self, output: *Output, tree: *wlr.SceneTree, impl: Impl) erro
             .top = try tree.createSceneRect(0, 0, &server.config.border_color_unfocused),
             .bottom = try tree.createSceneRect(0, 0, &server.config.border_color_unfocused),
         },
+        .popup_tree = try output.layers.popups.createSceneTree(),
         .current = .{ .tags = initial_tags },
         .pending = .{ .tags = initial_tags },
     };
+
+    try SceneNodeData.attach(&self.tree.node, .{ .view = self });
+    try SceneNodeData.attach(&self.popup_tree.node, .{ .view = self });
 }
 
 /// If saved buffers of the view are currently in use by a transaction,
@@ -211,6 +214,7 @@ pub fn updateCurrent(self: *Self) void {
 
     const box = &self.current.box;
     self.tree.node.setPosition(box.x, box.y);
+    self.popup_tree.node.setPosition(box.x, box.y);
 
     const border_width: c_int = config.border_width;
     self.borders.left.node.setPosition(-border_width, -border_width);
@@ -361,6 +365,13 @@ pub fn close(self: Self) void {
     }
 }
 
+pub fn destroyPopups(self: Self) void {
+    switch (self.impl) {
+        .xdg_toplevel => |xdg_toplevel| xdg_toplevel.destroyPopups(),
+        .xwayland_view => {},
+    }
+}
+
 pub fn setActivated(self: Self, activated: bool) void {
     switch (self.impl) {
         .xdg_toplevel => |xdg_toplevel| xdg_toplevel.setActivated(activated),
@@ -489,6 +500,7 @@ pub fn map(self: *Self) !void {
     log.debug("view '{?s}' mapped", .{self.getTitle()});
 
     self.tree.node.setEnabled(true);
+    self.popup_tree.node.setEnabled(true);
 
     server.xdg_activation.events.request_activate.add(&self.request_activate);
 
@@ -510,6 +522,7 @@ pub fn unmap(self: *Self) void {
     log.debug("view '{?s}' unmapped", .{self.getTitle()});
 
     self.tree.node.setEnabled(false);
+    self.popup_tree.node.setEnabled(false);
 
     if (self.saved_buffers.items.len == 0) self.saveBuffers();
 

river/XdgPopup.zig

@@ -0,0 +1,105 @@
+// This file is part of river, a dynamic tiling wayland compositor.
+//
+// Copyright 2023 The River Developers
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, version 3.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program. If not, see <https://www.gnu.org/licenses/>.
+
+const XdgPopup = @This();
+
+const std = @import("std");
+const wlr = @import("wlroots");
+const wl = @import("wayland").server.wl;
+
+const server = &@import("main.zig").server;
+const util = @import("util.zig");
+
+const Output = @import("Output.zig");
+
+const log = std.log.scoped(.xdg_popup);
+
+wlr_xdg_popup: *wlr.XdgPopup,
+/// This isn't terribly clean, but pointing to the output field of the parent
+/// View or LayerSurface struct is ok in practice as all popups are destroyed
+/// before their parent View or LayerSurface.
+output: *const *Output,
+/// The root of the surface tree, i.e. the View or LayerSurface popup_tree.
+root: *wlr.SceneTree,
+
+tree: *wlr.SceneTree,
+
+destroy: wl.Listener(void) = wl.Listener(void).init(handleDestroy),
+new_popup: wl.Listener(*wlr.XdgPopup) = wl.Listener(*wlr.XdgPopup).init(handleNewPopup),
+reposition: wl.Listener(void) = wl.Listener(void).init(handleReposition),
+
+pub fn create(
+    wlr_xdg_popup: *wlr.XdgPopup,
+    root: *wlr.SceneTree,
+    parent: *wlr.SceneTree,
+    output: *const *Output,
+) error{OutOfMemory}!void {
+    const xdg_popup = try util.gpa.create(XdgPopup);
+    errdefer util.gpa.destroy(xdg_popup);
+
+    xdg_popup.* = .{
+        .wlr_xdg_popup = wlr_xdg_popup,
+        .output = output,
+        .root = root,
+        .tree = try parent.createSceneXdgSurface(wlr_xdg_popup.base),
+    };
+
+    wlr_xdg_popup.base.events.destroy.add(&xdg_popup.destroy);
+    wlr_xdg_popup.base.events.new_popup.add(&xdg_popup.new_popup);
+    wlr_xdg_popup.events.reposition.add(&xdg_popup.reposition);
+
+    handleReposition(&xdg_popup.reposition);
+}
+
+fn handleDestroy(listener: *wl.Listener(void)) void {
+    const xdg_popup = @fieldParentPtr(XdgPopup, "destroy", listener);
+
+    xdg_popup.destroy.link.remove();
+    xdg_popup.new_popup.link.remove();
+    xdg_popup.reposition.link.remove();
+
+    util.gpa.destroy(xdg_popup);
+}
+
+fn handleNewPopup(listener: *wl.Listener(*wlr.XdgPopup), wlr_xdg_popup: *wlr.XdgPopup) void {
+    const xdg_popup = @fieldParentPtr(XdgPopup, "new_popup", listener);
+
+    XdgPopup.create(
+        wlr_xdg_popup,
+        xdg_popup.root,
+        xdg_popup.tree,
+        xdg_popup.output,
+    ) catch {
+        wlr_xdg_popup.resource.postNoMemory();
+        return;
+    };
+}
+
+fn handleReposition(listener: *wl.Listener(void)) void {
+    const xdg_popup = @fieldParentPtr(XdgPopup, "reposition", listener);
+
+    var box: wlr.Box = undefined;
+    server.root.output_layout.getBox(xdg_popup.output.*.wlr_output, &box);
+
+    var root_lx: c_int = undefined;
+    var root_ly: c_int = undefined;
+    _ = xdg_popup.root.node.coords(&root_lx, &root_ly);
+
+    box.x -= root_lx;
+    box.y -= root_ly;
+
+    xdg_popup.wlr_xdg_popup.unconstrainFromBox(&box);
+}

river/XdgToplevel.zig

@@ -26,6 +26,7 @@ const util = @import("util.zig");
 
 const Output = @import("Output.zig");
 const Seat = @import("Seat.zig");
+const XdgPopup = @import("XdgPopup.zig");
 const View = @import("View.zig");
 const ViewStack = @import("view_stack.zig").ViewStack;
 
@@ -44,6 +45,7 @@ acked_pending_serial: bool = false,
 destroy: wl.Listener(void) = wl.Listener(void).init(handleDestroy),
 map: wl.Listener(void) = wl.Listener(void).init(handleMap),
 unmap: wl.Listener(void) = wl.Listener(void).init(handleUnmap),
+new_popup: wl.Listener(*wlr.XdgPopup) = wl.Listener(*wlr.XdgPopup).init(handleNewPopup),
 
 // Listeners that are only active while the view is mapped
 ack_configure: wl.Listener(*wlr.XdgSurface.Configure) =
@@ -78,6 +80,7 @@ pub fn create(output: *Output, xdg_toplevel: *wlr.XdgToplevel) error{OutOfMemory
     xdg_toplevel.base.events.destroy.add(&self.destroy);
     xdg_toplevel.base.events.map.add(&self.map);
     xdg_toplevel.base.events.unmap.add(&self.unmap);
+    xdg_toplevel.base.events.new_popup.add(&self.new_popup);
 }
 
 /// Returns true if a configure must be sent to ensure that the pending
@@ -145,6 +148,11 @@ pub fn getConstraints(self: Self) View.Constraints {
     };
 }
 
+pub fn destroyPopups(self: Self) void {
+    var it = self.xdg_toplevel.base.popups.safeIterator(.forward);
+    while (it.next()) |wlr_xdg_popup| wlr_xdg_popup.destroy();
+}
+
 fn handleDestroy(listener: *wl.Listener(void)) void {
     const self = @fieldParentPtr(Self, "destroy", listener);
 
@@ -233,6 +241,20 @@ fn handleUnmap(listener: *wl.Listener(void)) void {
     self.view.unmap();
 }
 
+fn handleNewPopup(listener: *wl.Listener(*wlr.XdgPopup), wlr_xdg_popup: *wlr.XdgPopup) void {
+    const self = @fieldParentPtr(Self, "new_popup", listener);
+
+    XdgPopup.create(
+        wlr_xdg_popup,
+        self.view.popup_tree,
+        self.view.popup_tree,
+        &self.view.output,
+    ) catch {
+        wlr_xdg_popup.resource.postNoMemory();
+        return;
+    };
+}
+
 fn handleAckConfigure(
     listener: *wl.Listener(*wlr.XdgSurface.Configure),
     acked_configure: *wlr.XdgSurface.Configure,