changeset:   576074:12385afb25c9
tag:         tip
parent:      576071:a3bc2d23debb
user:        stransky <stransky@redhat.com>
date:        Wed Mar 31 16:37:22 2021 +0200
files:       modules/libpref/init/StaticPrefList.yaml widget/gtk/WindowSurfaceWayland.cpp widget/gtk/WindowSurfaceWayland.h
description:
Bug 1693472 [Wayland] Always use direct drawing on KWim, r?jhorak

Differential Revision: https://phabricator.services.mozilla.com/D110427


diff --git a/modules/libpref/init/StaticPrefList.yaml b/modules/libpref/init/StaticPrefList.yaml
--- a/modules/libpref/init/StaticPrefList.yaml
+++ b/modules/libpref/init/StaticPrefList.yaml
@@ -10991,10 +10991,13 @@
   mirror: always
 #endif
 
-# Use smooth rendering for Wayland basic compositor.
+# Smooth rendering mode for Wayland basic compositor.
+# 0 - direct draw
+# 1 - basic caching
+# 2 - all caching
 - name: widget.wayland-smooth-rendering
-  type: RelaxedAtomicBool
-  value: false
+  type: RelaxedAtomicUint32
+  value: 1
   mirror: always
 
 # Use DMABuf backend for WebGL.
diff --git a/widget/gtk/WindowSurfaceWayland.cpp b/widget/gtk/WindowSurfaceWayland.cpp
--- a/widget/gtk/WindowSurfaceWayland.cpp
+++ b/widget/gtk/WindowSurfaceWayland.cpp
@@ -487,6 +487,11 @@ WindowSurfaceWayland::WindowSurfaceWayla
   for (int i = 0; i < BACK_BUFFER_NUM; i++) {
     mShmBackupBuffer[i] = nullptr;
   }
+  // Use slow compositing on KDE only.
+  const char* currentDesktop = getenv("XDG_CURRENT_DESKTOP");
+  if (currentDesktop && strstr(currentDesktop, "KDE") != nullptr) {
+    mSmoothRendering = CACHE_NONE;
+  }
 }
 
 WindowSurfaceWayland::~WindowSurfaceWayland() {
@@ -817,13 +822,12 @@ already_AddRefed<gfx::DrawTarget> Window
     mMozContainerRect = mozContainerSize;
   }
 
-  // We can draw directly only when we redraw significant part of the window
-  // to avoid flickering or do only fullscreen updates in smooth mode.
-  mDrawToWaylandBufferDirectly =
-      mSmoothRendering
-          ? windowRedraw
-          : (windowRedraw || (lockSize.width * 2 > mozContainerSize.width &&
-                              lockSize.height * 2 > mozContainerSize.height));
+  mDrawToWaylandBufferDirectly = windowRedraw || mSmoothRendering == CACHE_NONE;
+  if (!mDrawToWaylandBufferDirectly && mSmoothRendering == CACHE_SMALL) {
+    mDrawToWaylandBufferDirectly =
+        (lockSize.width * 2 > mozContainerSize.width &&
+         lockSize.height * 2 > mozContainerSize.height);
+  }
 
   if (!mDrawToWaylandBufferDirectly) {
     // Don't switch wl_buffers when we cache drawings.
diff --git a/widget/gtk/WindowSurfaceWayland.h b/widget/gtk/WindowSurfaceWayland.h
--- a/widget/gtk/WindowSurfaceWayland.h
+++ b/widget/gtk/WindowSurfaceWayland.h
@@ -149,19 +149,6 @@ class WindowSurfaceWayland : public Wind
 
   RefPtr<nsWaylandDisplay> GetWaylandDisplay() { return mWaylandDisplay; };
 
-  // Image cache mode can be set by widget.wayland_cache_mode
-  typedef enum {
-    // Cache and clip all drawings, default. It's slowest
-    // but also without any rendered artifacts.
-    CACHE_ALL = 0,
-    // Cache drawing only when back buffer is missing. May produce
-    // some rendering artifacts and flickering when partial screen update
-    // is rendered.
-    CACHE_MISSING = 1,
-    // Don't cache anything, draw only when back buffer is available.
-    CACHE_NONE = 2
-  } RenderingCacheMode;
-
  private:
   WindowBackBuffer* GetWaylandBuffer();
   WindowBackBuffer* SetNewWaylandBuffer();
@@ -251,9 +238,18 @@ class WindowSurfaceWayland : public Wind
   // This typically apply to popup windows.
   bool mBufferNeedsClear;
 
+  typedef enum {
+    // Don't cache anything, always draw directly to wl_buffer
+    CACHE_NONE = 0,
+    // Cache only small paints (smaller than 1/2 of screen).
+    CACHE_SMALL = 1,
+    // Cache all painting except fullscreen updates.
+    CACHE_ALL = 2,
+  } RenderingCacheMode;
+
   // Cache all drawings except fullscreen updates.
   // Avoid any rendering artifacts for significant performance penality.
-  bool mSmoothRendering;
+  unsigned int mSmoothRendering;
 
   gint mSurfaceReadyTimerID;
   mozilla::Mutex mSurfaceLock;