x11-kiosk: defer fullscreening of applications until they are placed …

…once (#3670)

Fix the "black screen" problem with vmware-view

examples/mir-x11-kiosk/x11_kiosk_window_manager.cpp

@@ -106,13 +106,22 @@ void X11KioskWindowManagerPolicy::handle_modify_window(WindowInfo& window_info,
             tools.modify_window(window_info, mods);
         }
 
-        specification.state() = mir_window_state_fullscreen;
-        specification.size() = mir::optional_value<Size>{}; // Ignore requested size (if any) when we fullscreen
-        specification.top_left() = mir::optional_value<Point>{}; // Ignore requested position (if any) when we fullscreen
-        tools.place_and_size_for_state(specification, window_info);
+        if (window_info.is_visible() || !modifications.state().is_set() || modifications.state().value() != mir_window_state_restored)
+        {
+            specification.state() = mir_window_state_fullscreen;
+            specification.size() = mir::optional_value<Size>{}; // Ignore requested size (if any) when we fullscreen
+            specification.top_left() = mir::optional_value<Point>{}; // Ignore requested position (if any) when we fullscreen
+            tools.place_and_size_for_state(specification, window_info);
 
-        if (!modifications.state().is_set() || modifications.state().value() != mir_window_state_restored)
-            specification.state() = modifications.state();
+            if (!modifications.state().is_set() || modifications.state().value() != mir_window_state_restored)
+                specification.state() = modifications.state();
+        }
+        else
+        {
+            // We have one X11 application (vmware-view) that doesn't submit any buffers unless it
+            // can first "restore" its window
+            tools.place_and_size_for_state(specification, window_info);
+        }
     }
 
     CanonicalWindowManagerPolicy::handle_modify_window(window_info, specification);
@@ -132,3 +141,21 @@ X11KioskWindowManagerPolicy::confirm_placement_on_display(WindowInfo const& /*wi
 {
     return new_placement;
 }
+
+void X11KioskWindowManagerPolicy::handle_window_ready(miral::WindowInfo& window_info)
+{
+    if ((window_info.type() == mir_window_type_normal || window_info.type() == mir_window_type_freestyle) &&
+        !window_info.parent())
+    {
+        // We have one X11 application (vmware-view) that doesn't submit any buffers unless it
+        // can first "restore" its window. We've got a buffer now, so we can fullscreen it
+        if (window_info.state() == mir_window_state_restored)
+        {
+            WindowSpecification specification;
+            specification.state() = mir_window_state_fullscreen;
+            tools.place_and_size_for_state(specification, WindowInfo{});
+            tools.modify_window(window_info, specification);
+        }
+    }
+    CanonicalWindowManagerPolicy::handle_window_ready(window_info);
+}

examples/mir-x11-kiosk/x11_kiosk_window_manager.h

@@ -37,8 +37,9 @@ class X11KioskWindowManagerPolicy : public miral::CanonicalWindowManagerPolicy
     void handle_modify_window(miral::WindowInfo& window_info, miral::WindowSpecification const& modifications) override;
 
     void handle_request_move(miral::WindowInfo& window_info, MirInputEvent const* input_event) override;
+    void handle_window_ready(miral::WindowInfo& window_info) override;
     void handle_request_resize(miral::WindowInfo& window_info, MirInputEvent const* input_event,
-        MirResizeEdge edge) override;
+                               MirResizeEdge edge) override;
 
     auto confirm_placement_on_display(const miral::WindowInfo& window_info, MirWindowState new_state,
         Rectangle const& new_placement) -> Rectangle override;

src/server/scene/surface_stack.cpp

@@ -131,7 +131,6 @@ struct SurfaceDepthLayerObserver : ms::NullSurfaceObserver
 
 ms::SurfaceStack::SurfaceStack(std::shared_ptr<SceneReport> const& report) :
     report{report},
-    scene_changed{false},
     surface_observer{std::make_shared<SurfaceDepthLayerObserver>(this)},
     multiplexer(linearising_executor)
 {
@@ -153,7 +152,6 @@ mc::SceneElementSequence ms::SurfaceStack::scene_elements_for(mc::CompositorID i
 {
     RecursiveReadLock lg(guard);
 
-    scene_changed = false;
     mc::SceneElementSequence elements;
     for (auto const& layer : surface_layers)
     {
@@ -227,10 +225,6 @@ void ms::SurfaceStack::remove_input_visualization(
 
 void ms::SurfaceStack::emit_scene_changed()
 {
-    {
-        RecursiveWriteLock lg(guard);
-        scene_changed = true;
-    }
     observers.scene_changed();
 }
 

src/server/scene/surface_stack.h

@@ -160,7 +160,6 @@ class SurfaceStack :
     Observers observers;
     /// If not expired the screen is locked (and only surfaces that appear on the lock screen should be shown)
     std::atomic<bool> is_locked = false;
-    std::atomic<bool> scene_changed;
     std::shared_ptr<SurfaceObserver> surface_observer;
     SessionLockObserverMultiplexer multiplexer;
 };