cc: PaintTimeCounter display on the HudLayer in continuous painting mode

cc/heads_up_display_layer_impl.h

Index: cc/heads_up_display_layer_impl.h
diff --git a/cc/heads_up_display_layer_impl.h b/cc/heads_up_display_layer_impl.h
index 70bf03ec867e0da20a2435ab114b426aba737729..6aef447481453e7210e16d5931d1bb0c857f0d3a 100644
--- a/cc/heads_up_display_layer_impl.h
+++ b/cc/heads_up_display_layer_impl.h
@@ -21,6 +21,7 @@ namespace cc {
 class DebugRectHistory;
 class FontAtlas;
 class FrameRateCounter;
+class PaintTimeCounter;
 
 class CC_EXPORT HeadsUpDisplayLayerImpl : public LayerImpl {
 public:
@@ -42,25 +43,47 @@ public:
     virtual bool layerIsAlwaysDamaged() const OVERRIDE;
 
 private:
+    struct Graph {
+        Graph(double indicatorValue, double startHigh);
+
+        // Eases the high value, which is the upper limit of what is currently visible in the graph,
+        // so that the graph always scales to either it's max or defaultHigh.
+        static double updateHigh(Graph&);

[shawnsingh, 2013/01/15 22:48:52]

If Graph is supposed to be non-const, let's use a pointer here.  I know some
other places in this file are using non-const references instead of pointers,
but we should also eventually be migrating those from the webkit style to
chromium style eventually, too.  This is one style point I feel we should go
ahead and use chromium style even if the rest of the file is still using webkit
style.

+
+        double current;
+        double min;
+        double max;
+        double high;
+
+        const double defaultHigh;
+        const double indicator;
+    };
+
     HeadsUpDisplayLayerImpl(LayerTreeImpl* treeImpl, int id);
 
     virtual const char* layerTypeAsString() const OVERRIDE;
 
     void drawHudContents(SkCanvas*);
-    int drawFPSCounter(SkCanvas*, FrameRateCounter*);
-    void drawFPSCounterText(SkCanvas*, SkPaint&, FrameRateCounter*, SkRect);
-    void drawFPSCounterGraphAndHistogram(SkCanvas* canvas, SkPaint& paint, FrameRateCounter* fpsCounter, SkRect graphBounds, SkRect histogramBounds);
+
+    void drawTextLeftAligned(SkCanvas*, SkPaint&, SkRect bounds, std::string text);

[shawnsingh, 2013/01/15 22:48:52]

same here and for all the following functions - either pointer or const&

+    void drawTextRightAligned(SkCanvas*, SkPaint&, SkRect bounds, std::string text);
+
+    void drawGraphBackground(SkCanvas*, SkPaint&, SkRect bounds);
+    void drawGraphLines(SkCanvas*, SkPaint&, SkRect bounds, Graph&);
+
+    int drawFPSDisplay(SkCanvas*, FrameRateCounter*, int top);
+    int drawPaintTimeDisplay(SkCanvas*, PaintTimeCounter*, int top);
+
     void drawDebugRects(SkCanvas*, DebugRectHistory*);
 
     scoped_ptr<FontAtlas> m_fontAtlas;
     scoped_ptr<ScopedResource> m_hudTexture;
     scoped_ptr<SkCanvas> m_hudCanvas;
 
-    double m_averageFPS;
-    double m_minFPS;
-    double m_maxFPS;
+    Graph m_fpsGraph;
+    Graph m_paintTimeGraph;
 
-    base::TimeTicks textUpdateTime;
+    base::TimeTicks m_lastGraphNumbersUpdate;

[shawnsingh, 2013/01/15 22:48:52]

more nitpickyness -  perhaps this is more clear named as "timeOfLastGraphUpdate"

 };
 
 }  // namespace cc