Start of hardware overlay support in CC with Ubercompositor.

cc/output/overlay_candidates.h

Index: cc/output/overlay_candidates.h
diff --git a/ui/gfx/ozone/overlay_candidates_ozone.h b/cc/output/overlay_candidates.h
similarity index 61%
copy from ui/gfx/ozone/overlay_candidates_ozone.h
copy to cc/output/overlay_candidates.h
index 85e21b982027b1b5ac4b4800a5487311e3104beb..0041eb558bd29da8ecf13d28810cfa52ea93e7d0 100644
--- a/ui/gfx/ozone/overlay_candidates_ozone.h
+++ b/cc/output/overlay_candidates.h
@@ -2,35 +2,45 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef UI_GFX_OZONE_OVERLAY_CANDIDATES_OZONE_H_
-#define UI_GFX_OZONE_OVERLAY_CANDIDATES_OZONE_H_
+#ifndef CC_OUTPUT_OVERLAY_CANDIDATES_H_
+#define CC_OUTPUT_OVERLAY_CANDIDATES_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
-#include "ui/gfx/gfx_export.h"
-#include "ui/gfx/ozone/surface_factory_ozone.h"
-#include "ui/gfx/rect_f.h"
+#include "cc/base/cc_export.h"
+#include "cc/resources/resource_format.h"
+#include "ui/gfx/geometry/rect.h"
 
-namespace gfx {
+namespace cc {
 
-// This class can be used to answer questions about possible overlay
-// configurations for a particular output device. We get an instance of this
-// class from SurfaceFactoryOzone given an AcceleratedWidget.
-class GFX_EXPORT OverlayCandidatesOzone {
+// This class that can be used to answer questions about possible overlay
+// configurations for a particular output device.
+class CC_EXPORT OverlayCandidates {

[enne (OOO), 2014/03/14 18:13:41]

bikeshed: If it answers questions, maybe this is an OverlayCandidateGenerator?
OverlayCandidateValidator? It seems more like a "verb" class than a "noun"
class.

[alexst (slow to review), 2014/03/14 19:54:22]

This name is a result of bikeshedding elsewhere. :) But I'm not attached to it
and will play by CC rules here. OverlayCandidateValidator sounds good to me.

  public:
+  enum OverlayTransform {
+    NONE,
+    FLIP_HORIZONTAL,
+    FLIP_VERTICAL,
+    ROTATE_90,
+    ROTATE_180,
+    ROTATE_270,
+  };
+
   struct OverlaySurfaceCandidate {

[enne (OOO), 2014/03/14 18:13:41]

Move this out to a separate file, to narrow visibility? Some class will deal
with OverlayCandidate but not with OverlayCandidates it seems.

     OverlaySurfaceCandidate();
     ~OverlaySurfaceCandidate();
 
     // Transformation to apply to layer during composition.
-    SurfaceFactoryOzone::OverlayTransform transform;
+    OverlayTransform transform;
     // Format of the buffer to composite.
-    SurfaceFactoryOzone::BufferFormat format;
+    ResourceFormat format;
     // Rect on the display to position the overlay to.
     gfx::Rect display_rect;
     // Crop within the buffer to be placed inside |display_rect|.

[enne (OOO), 2014/03/14 18:13:41]

Can you say that this is in uv space and not in pixel space? Or maybe even call
it uv_rect?

     gfx::RectF crop_rect;
+    // Resource id of the buffer to present.
+    unsigned resource_id;

[piman, 2014/03/14 03:42:34]

Will we need things like blending mode or something? I suppose that can come in
time as we expand support?

[alexst (slow to review), 2014/03/14 19:54:22]

Yeah, I was going for a minimal subset and omitted a few other things too. I'll
add other fields once more stuff is in place.

 
     // To be modified by the implementer if this candidate can go into
     // an overlay.
@@ -45,9 +55,9 @@ class GFX_EXPORT OverlayCandidatesOzone {
   // to be tranditionally composited.

[enne (OOO), 2014/03/14 18:13:41]

typo

[alexst (slow to review), 2014/03/14 19:54:22]

Done.

   virtual void CheckOverlaySupport(OverlaySurfaceCandidateList* surfaces);

[piman, 2014/03/14 03:42:34]

pure virtual?

[alexst (slow to review), 2014/03/14 19:54:22]

Done.

 
-  virtual ~OverlayCandidatesOzone();
+  virtual ~OverlayCandidates();
 };
 
-}  // namespace gfx
+}  // namespace cc
 
-#endif  // UI_GFX_OZONE_OVERLAY_CANDIDATES_OZONE_H_
+#endif  // CC_OUTPUT_OVERLAY_CANDIDATES_H_