Changeset 196623 in webkit

Timestamp:

Feb 15, 2016 9:39:57 PM (8 years ago)

Author:

ChangSeok Oh

Message:

[ThreadedCompositor] position:fixed elements do not have their own layers when threaded compositor is enabled.
​https://bugs.webkit.org/show_bug.cgi?id=154100

Reviewed by Carlos Garcia Campos.

Currently, fixed elements are redrawn to a backing store every time layout or scroll happens.
It results in the bad effect on performance-wise. Letting fixed element have separate layers is
necessary when threaded compositor is enabled at least. Because async scrolling requires it.

• WebProcess/WebPage/DrawingAreaImpl.cpp:

(WebKit::DrawingAreaImpl::updatePreferences):

Location:

trunk/Source/WebKit2

Files:

• ChangeLog (modified) (1 diff)
• WebProcess/WebPage/DrawingAreaImpl.cpp (modified) (1 diff)

trunk/Source/WebKit2/ChangeLog

@@ +1 @@
+2016-02-15  ChangSeok Oh  <changseok.oh@collabora.com>
+
+        [ThreadedCompositor] position:fixed elements do not have their own layers when threaded compositor is enabled.
+        https://bugs.webkit.org/show_bug.cgi?id=154100
+
+        Reviewed by Carlos Garcia Campos.
+
+        Currently, fixed elements are redrawn to a backing store every time layout or scroll happens.
+        It results in the bad effect on performance-wise. Letting fixed element have separate layers is
+        necessary when threaded compositor is enabled at least. Because async scrolling requires it.
+
+        * WebProcess/WebPage/DrawingAreaImpl.cpp:
+        (WebKit::DrawingAreaImpl::updatePreferences):
+
 2016-02-15  Alex Christensen  <achristensen@webkit.org>
 

trunk/Source/WebKit2/WebProcess/WebPage/DrawingAreaImpl.cpp

@@ -249 +249 @@
 void DrawingAreaImpl::updatePreferences(const WebPreferencesStore& store)
 {
-    m_webPage.corePage()->settings().setForceCompositingMode(store.getBoolValueForKey(WebPreferencesKey::forceCompositingModeKey()));
+    Settings& settings = m_webPage.corePage()->settings();
+    settings.setForceCompositingMode(store.getBoolValueForKey(WebPreferencesKey::forceCompositingModeKey()));
+
+#if USE(COORDINATED_GRAPHICS_THREADED)
+    // Fixed position elements need to be composited and create stacking contexts
+    // in order to be scrolled by the ScrollingCoordinator.
+    settings.setAcceleratedCompositingForFixedPositionEnabled(true);
+    settings.setFixedPositionCreatesStackingContext(true);
+#endif
 }