ozone: Add OzoneSurface object that is owned by compositor, GLSurface

ui/gfx/ozone/surface_ozone.h

+// Copyright 2014 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_EGL_SURFACE_OZONE_H_
+#define UI_GFX_OZONE_EGL_SURFACE_OZONE_H_
+
+#include "base/basictypes.h"
+#include "base/memory/scoped_ptr.h"
+#include "skia/ext/refptr.h"
+#include "ui/gfx/gfx_export.h"
+
+class SkCanvas;
+
+namespace gfx {
+
+class Size;
+class VSyncProvider;
+
+// The platform-specific part of an EGL surface or software output.
+//
+// This class owns any bits that the ozone implementation needs freed when
+// the software output or EGL surface is destroyed.
+//
+// If you want to paint on a window with ozone, you need to create a
+// SurfaceOzone for that window.
+//
+// The platform can support software, EGL, or both for painting on the
+// window. It is not necessary to override any methods for modes the
+// platform doesn't support, as the base class will fail initialization for

[rjkroege, 2014/03/26 19:59:02]

nit: "will provide no-op implementations for all methods"

[spang, 2014/03/26 22:21:28]

My idea was that InitializeFoo() in the base class returns false, and in that
case it's a bug to call any others since you fail the precondition.

In fact in this patch the default GetEGLNativeWindow and GetCanvas are not
merely unimplemented but NOTREACHED().

This is what I was trying to communicate.

+// all modes.
+class GFX_EXPORT SurfaceOzone {
+ public:
+  SurfaceOzone();
+  virtual ~SurfaceOzone();
+
+  // Initialize the surface for output using EGL/GLES2. Returns true if
+  // initialization was successful.
+  virtual bool InitializeEGL();
+
+  // Returns the EGL native window for rendering onto this surface.
+  // This can be used to to create a GLSurface.
+  virtual intptr_t /* EGLNativeWindowType */ GetEGLNativeWindow();
+
+  // Initialize canvas for software output. Returns true of initialization

[rjkroege, 2014/03/26 19:59:02]

s/of/if/

[spang, 2014/03/26 22:21:28]

Doh! I swear I did this already..

+  // was successful.
+  virtual bool InitializeCanvas();
+
+  // Returns an SkCanvas for drawing on the window. The canvas is intended
+  // for use when no EGL/GLES2 acceleration is possible.
+  virtual skia::RefPtr<SkCanvas> GetCanvas();

[rjkroege, 2014/03/26 19:59:02]

GetDrawableCanvas? 

[spang, 2014/03/26 22:21:28]

If we had both GetDrawableCanvas and GetCanvas, what would the difference be?

Doesn't seem like there is one. And so I like the simpler name.

+
+  // Attempts to resize the canvas to match the viewport size. Returns true if
+  // resizing was successful, otherwise false (platforms may require a fixed
+  // size canvas). After resizing, the compositor must call GetCanvas() to get
+  // the next canvas.
+  virtual bool ResizeCanvas(const gfx::Size& viewport_size);
+
+  // Present the current canvas. After presenting, the compositor must call
+  // GetCanvas() to get the next canvas.
+  virtual bool SwapCanvas();

[rjkroege, 2014/03/26 19:59:02]

call this "PresentCurrentCanvas" and reduce the comment.

[spang, 2014/03/26 22:21:28]

Hah, I was thinking it should say Present as well. How about PresentCanvas?

Or maybe GetCurrentCanvas + PresentCurrentCanvas?

I think it's probably just THE canvas.

+
+  // Returns a gfx::VsyncProvider for this surface. Note that this may be
+  // called after we have entered the sandbox so if there are operations (e.g.
+  // opening a file descriptor providing vsync events) that must be done
+  // outside of the sandbox, they must have been completed in
+  // InitializeHardware. Returns an empty scoped_ptr on error.
+  virtual scoped_ptr<gfx::VSyncProvider> CreateVSyncProvider();
+};
+
+}  // namespace gfx
+
+#endif  // UI_GFX_OZONE_SURFACE_OZONE_H_