Fix framerate cap when multiple webviews exist.

Each view will now be capped at 60fps. The previous code would
either starve the drawing of additional webviews or would draw
them at a rate of 60fps/N where N is the number of webviews.

Change-Id: I5698d610b17d4c8cfe137c51c2b978dae04ae1cf

diff --git a/WebCore/platform/graphics/android/GLWebViewState.cpp b/WebCore/platform/graphics/android/GLWebViewState.cpp
index 3ca04e9..c65b763 100644 (file)
--- a/WebCore/platform/graphics/android/GLWebViewState.cpp
+++ b/WebCore/platform/graphics/android/GLWebViewState.cpp
@@ -71,6 +71,7 @@ GLWebViewState::GLWebViewState(android::Mutex* buttonMutex)
     , m_globalButtonMutex(buttonMutex)
     , m_baseLayerUpdate(true)
     , m_backgroundColor(SK_ColorWHITE)
+    , m_prevDrawTime(0)
 {
     m_viewport.setEmpty();
     m_previousViewport.setEmpty();
@@ -301,19 +302,17 @@ void GLWebViewState::setViewport(SkRect& viewport, float scale)
     m_tiledPageB->updateBaseTileSize();
 }
 
-static double gPrevTime = 0;
-
 bool GLWebViewState::drawGL(IntRect& rect, SkRect& viewport, float scale, SkColor color)
 {
     glFinish();
 
     double currentTime = WTF::currentTime();
-    double delta = currentTime - gPrevTime;
+    double delta = currentTime - m_prevDrawTime;
 
     if (delta < FRAMERATE_CAP)
         return true;
 
-    gPrevTime = currentTime;
+    m_prevDrawTime = currentTime;
 
     m_baseLayerLock.lock();
     BaseLayerAndroid* baseLayer = m_currentBaseLayer;

diff --git a/WebCore/platform/graphics/android/GLWebViewState.h b/WebCore/platform/graphics/android/GLWebViewState.h
index d265b41..e44ec3c 100644 (file)
--- a/WebCore/platform/graphics/android/GLWebViewState.h
+++ b/WebCore/platform/graphics/android/GLWebViewState.h
@@ -252,6 +252,7 @@ private:
     IntRect m_invalidateRect;
 
     SkColor m_backgroundColor;
+    double m_prevDrawTime;
 };
 
 } // namespace WebCore