Overlay interface for ozone.

ui/gfx/ozone/overlay_candidates_ozone.h

+// Copyright 2012 The Chromium Authors. All rights reserved.
+// 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_
+
+#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"
+
+namespace gfx {
+
+// This class that can be used to answer questions about possible overlay
+// configurations for a particular output device.
+class GFX_EXPORT OverlayCandidatesOzone {
+ public:
+  struct OverlaySurfaceCandidate {
+    OverlaySurfaceCandidate();
+    ~OverlaySurfaceCandidate();
+
+    // Transformation to apply to layer during composition.
+    SurfaceFactoryOzone::OverlayTransform transform;
+    // Format of the buffer to composite.
+    SurfaceFactoryOzone::BufferFormat format;
+    // Rect on the display to position the overlay to.
+    gfx::Rect display_rect;

[rjkroege, 2014/02/28 23:02:47]

if these are not the same, how should the hardware composer handle it?

[alexst (slow to review), 2014/03/03 18:36:24]

Like texturing in GL, you put the crop rect from the buffer into display rect,
resizing as necessary.

+    // Crop within the buffer.
+    gfx::RectF crop_rect;
+
+    // To be modified by the implementer if this candidate can go into
+    // an overlay.
+    bool overlay_handled;
+  };
+
+  typedef std::vector<OverlaySurfaceCandidate> OverlaySurfaceCandidateList;
+
+  // A list of possible overlay candidates is presented to this function.
+  // The expected result is that those candidates that can be in a separate
+  // plane are marked with |overlay_handled| set to true, otherwise they are
+  // to be tranditionally composited.
+  virtual void CheckOverlaySupport(OverlaySurfaceCandidateList* surfaces);
+
+  virtual ~OverlayCandidatesOzone();
+};
+
+}  // namespace gfx
+
+#endif  // UI_GFX_OZONE_OVERLAY_CANDIDATES_OZONE_H_