Implementation for cc::Picture::IsCheapInRect().

cc/picture.cc

Index: cc/picture.cc
diff --git a/cc/picture.cc b/cc/picture.cc
index 55dbd8afb890dbc707bc345d54f84e379e99a131..046f37e3d6f2a7ee83078ca1a2db853621ec6c26 100644
--- a/cc/picture.cc
+++ b/cc/picture.cc
@@ -101,23 +101,11 @@ void Picture::Raster(
     SkCanvas* canvas,
     gfx::Rect content_rect,
     float contents_scale) {
-char strbuf[256];
-if (IsCheapInRect(content_rect)) {
-sprintf(strbuf, "CHEAP Picture::Raster");
-} else {
-sprintf(strbuf, "EXPENSIVE Picture::Raster");
-}
-SkBitmap emptyBitmap;
-emptyBitmap.setConfig(SkBitmap::kARGB_8888_Config, picture_->width(),
-                      picture_->height());
-skia::AnalysisDevice device(emptyBitmap);
-skia::AnalysisCanvas aCanvas(&device, gfx::RectToSkRect(content_rect));
-aCanvas.drawPicture(*picture_);
-TRACE_EVENT1("cc", strdup(strbuf), "cost", aCanvas.getEstimatedCost());
-  //TRACE_EVENT2("cc", strdup(strbuf),
-               //"width", layer_rect_.width(), "height", layer_rect_.height());
+  TRACE_EVENT2("cc", "Picture::Raster",
+               "width", layer_rect_.width(), "height", layer_rect_.height());
   DCHECK(picture_);
 
+  bool isCheap = IsCheapInRect(content_rect, contents_scale);
   canvas->save();
   canvas->clipRect(gfx::RectToSkRect(content_rect));
   canvas->scale(contents_scale, contents_scale);
@@ -126,17 +114,19 @@ TRACE_EVENT1("cc", strdup(strbuf), "cost", aCanvas.getEstimatedCost());
   canvas->restore();
 }
 
-bool Picture::IsCheapInRect(const gfx::Rect& layer_rect) {
-TRACE_EVENT0("cc", "Picture::IsCheapInRect");
+bool Picture::IsCheapInRect(const gfx::Rect& layer_rect,
+                            float contents_scale) const {
+  TRACE_EVENT0("cc", "Picture::IsCheapInRect");
+
   SkBitmap emptyBitmap;
-  emptyBitmap.setConfig(SkBitmap::kNo_Config, picture_->width(),
-                        picture_->height());
+  emptyBitmap.setConfig(SkBitmap::kNo_Config, layer_rect.width(),
+                        layer_rect.height());
   skia::AnalysisDevice device(emptyBitmap);
-  skia::AnalysisCanvas canvas(&device, gfx::RectToSkRect(layer_rect));
-  // If a picture has low estimated cost, go ahead and
-  // wait until we have more pictures to draw (to amortize startup costs).
-  // If estimated cost is high, start it now so that compositing isn't
-  // blocked waiting for it.
+  skia::AnalysisCanvas canvas(&device);
+
+  canvas.clipRect(gfx::RectToSkRect(layer_rect));
+  canvas.scale(contents_scale, contents_scale);
+  canvas.translate(layer_rect_.x(), layer_rect_.y());
   canvas.drawPicture(*picture_);
   return canvas.isCheap();
 }