cc: Allow output readback/copy requests to specify a sub-rect to copy.

The CopyOutputRequest API is on cc::Layer, so the rect it is given
should be in layer space.

Also add tests for CompositeAndReadback which no longer had any pixel
test coverage in cc/ to ensure that its inputs are correctly applied
as device viewport space.

Clean up the layer tree pixel test framework by passing the test type
(GL/Software cross Bitmap/Texture) as a parameter to RunPixelTest()
instead of having tests set a pair of bools. Forces all tests to
specify the test type.

Tests:
LayerTreeHostReadbackPixelTest.ReadbackSubrect_Software
LayerTreeHostReadbackPixelTest.ReadbackSubrect_GL_Bitmap
LayerTreeHostReadbackPixelTest.ReadbackSubrect_GL
LayerTreeHostReadbackPixelTest.ReadbackNonRootLayerSubrect_Software
LayerTreeHostReadbackPixelTest.ReadbackNonRootLayerSubrect_GL_Bitmap
LayerTreeHostReadbackPixelTest.ReadbackNonRootLayerSubrect_GL
LayerTreeHostReadbackDeviceScalePixelTest.ReadbackSubrect_Software
LayerTreeHostReadbackDeviceScalePixelTest.ReadbackSubrect_GL
LayerTreeHostReadbackDeviceScalePixelTest.ReadbackNonRootLayerSubrect_Software
LayerTreeHostReadbackDeviceScalePixelTest.ReadbackNonRootLayerSubrect_GL
LayerTreeHostReadbackViaCompositeAndReadbackPixelTest.CompositeAndReadback_Software_1
LayerTreeHostReadbackViaCompositeAndReadbackPixelTest.CompositeAndReadback_Software_2
LayerTreeHostReadbackViaCompositeAndReadbackPixelTest.CompositeAndReadback_GL_1
LayerTreeHostReadbackViaCompositeAndReadbackPixelTest.CompositeAndReadback_GL_2

R=piman
BUG=251754
Merged https://codereview.chromium.org/17449014/ and
https://codereview.chromium.org/17261009/ into this CL.

Review URL: https://chromiumcodereview.appspot.com/17335011

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@207589 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 38 insertions, 8 deletions

diff --git a/cc/output/copy_output_request.cc b/cc/output/copy_output_request.cc
index 90ece04..341d887 100644
--- a/cc/output/copy_output_request.cc
+++ b/cc/output/copy_output_request.cc
@@ -19,6 +19,7 @@ CopyOutputRequest::CopyOutputRequest(
     bool force_bitmap_result,
     const CopyOutputRequestCallback& result_callback)
     : force_bitmap_result_(force_bitmap_result),
+      has_area_(false),
       result_callback_(result_callback) {
 }
 
diff --git a/cc/output/copy_output_request.h b/cc/output/copy_output_request.h
index 54fff1a..b7eb0b4 100644
--- a/cc/output/copy_output_request.h
+++ b/cc/output/copy_output_request.h
@@ -8,7 +8,7 @@
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "cc/base/cc_export.h"
-#include "ui/gfx/size.h"
+#include "ui/gfx/rect.h"
 
 class SkBitmap;
 
@@ -35,15 +35,29 @@ class CC_EXPORT CopyOutputRequest {
   static scoped_ptr<CopyOutputRequest> CreateRelayRequest(
       const CopyOutputRequest& original_request,
       const CopyOutputRequestCallback& result_callback) {
-    return make_scoped_ptr(new CopyOutputRequest(
-        original_request.force_bitmap_result(), result_callback));
+    scoped_ptr<CopyOutputRequest> relay = CreateRequest(result_callback);
+    relay->force_bitmap_result_ = original_request.force_bitmap_result_;
+    relay->has_area_ = original_request.has_area_;
+    relay->area_ = original_request.area_;
+    return relay.Pass();
   }
 
   ~CopyOutputRequest();
 
   bool IsEmpty() const { return result_callback_.is_null(); }
+
   bool force_bitmap_result() const { return force_bitmap_result_; }
 
+  // By default copy requests copy the entire layer's subtree output. If an
+  // area is given, then the intersection of this rect (in layer space) with
+  // the layer's subtree output will be returned.
+  void set_area(gfx::Rect area) {
+    has_area_ = true;
+    area_ = area;
+  }
+  bool has_area() const { return has_area_; }
+  gfx::Rect area() const { return area_; }
+
   void SendResult(scoped_ptr<CopyOutputResult> result);
   void SendBitmapResult(scoped_ptr<SkBitmap> bitmap);
   void SendTextureResult(gfx::Size size,
@@ -60,6 +74,8 @@ class CC_EXPORT CopyOutputRequest {
                              const CopyOutputRequestCallback& result_callback);
 
   bool force_bitmap_result_;
+  bool has_area_;
+  gfx::Rect area_;
   CopyOutputRequestCallback result_callback_;
 };
 
diff --git a/cc/output/gl_renderer.cc b/cc/output/gl_renderer.cc
index 2a27ff7..3527ed1 100644
--- a/cc/output/gl_renderer.cc
+++ b/cc/output/gl_renderer.cc
@@ -1914,8 +1914,13 @@ void GLRenderer::EnsureScissorTestDisabled() {
 void GLRenderer::CopyCurrentRenderPassToBitmap(
     DrawingFrame* frame,
     scoped_ptr<CopyOutputRequest> request) {
-  GetFramebufferPixelsAsync(frame->current_render_pass->output_rect,
-                            request.Pass());
+  gfx::Rect copy_rect = frame->current_render_pass->output_rect;
+  if (request->has_area()) {
+    // Intersect with the request's area, positioned with its origin at the
+    // origin of the full copy_rect.
+    copy_rect.Intersect(request->area() - copy_rect.OffsetFromOrigin());
+  }
+  GetFramebufferPixelsAsync(copy_rect, request.Pass());
 }
 
 void GLRenderer::ToGLMatrix(float* gl_matrix, const gfx::Transform& transform) {
diff --git a/cc/output/software_renderer.cc b/cc/output/software_renderer.cc
index 3cf1f6a..4b604a8 100644
--- a/cc/output/software_renderer.cc
+++ b/cc/output/software_renderer.cc
@@ -456,12 +456,20 @@ void SoftwareRenderer::DrawUnsupportedQuad(const DrawingFrame* frame,
 void SoftwareRenderer::CopyCurrentRenderPassToBitmap(
     DrawingFrame* frame,
     scoped_ptr<CopyOutputRequest> request) {
+  gfx::Rect copy_rect = frame->current_render_pass->output_rect;
+  if (request->has_area()) {
+    // Intersect with the request's area, positioned with its origin at the
+    // origin of the full copy_rect.
+    copy_rect.Intersect(request->area() - copy_rect.OffsetFromOrigin());
+  }
+  gfx::Rect window_copy_rect = MoveFromDrawToWindowSpace(copy_rect);
+
   scoped_ptr<SkBitmap> bitmap(new SkBitmap);
   bitmap->setConfig(SkBitmap::kARGB_8888_Config,
-                    current_viewport_rect_.width(),
-                    current_viewport_rect_.height());
+                    window_copy_rect.width(),
+                    window_copy_rect.height());
   current_canvas_->readPixels(
-      bitmap.get(), current_viewport_rect_.x(), current_viewport_rect_.y());
+      bitmap.get(), window_copy_rect.x(), window_copy_rect.y());
 
   request->SendBitmapResult(bitmap.Pass());
 }