Tweaks Compositor API. To make it possible to land this I've ifdef'd

the code in a couple of places.

BUG=none
TEST=none
R=ben@chromium.org,wjmaclean@chromium.org,rjkroege@chromium.org

Review URL: http://codereview.chromium.org/6999005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@84823 0039d316-1c4b-4281-b951-d872f2087c98

3 files changed, 125 insertions, 7 deletions

diff --git a/ui/gfx/compositor/compositor.gyp b/ui/gfx/compositor/compositor.gyp
index f739b93..98adcf8 100644
--- a/ui/gfx/compositor/compositor.gyp
+++ b/ui/gfx/compositor/compositor.gyp
@@ -3,6 +3,19 @@
 # found in the LICENSE file.
 
 {
+  'target_defaults': {
+    'sources/': [
+      ['exclude', '_(gl|win)\\.(cc?)$'],
+    ],
+    'conditions': [
+      ['OS=="linux" or OS=="freebsd" or OS=="openbsd"', {'sources/': [
+        ['include', '_(gl)\\.cc$'],
+      ]}],
+      ['OS=="win"', {'sources/': [
+        ['include', '_(win)\\.cc$'],
+      ]}],
+    ],
+  },
   'targets': [
     {
       'target_name': 'compositor',
@@ -10,25 +23,22 @@
       'msvs_guid': '21CEE0E3-6F4E-4F01-B8C9-F7751CC21AA9',
       'dependencies': [
         '<(DEPTH)/base/base.gyp:base',
+        '<(DEPTH)/skia/skia.gyp:skia',
         '<(DEPTH)/ui/gfx/gl/gl.gyp:gl',
         '<(DEPTH)/ui/ui.gyp:ui_gfx',
       ],
       'sources': [
         'compositor.cc',
-        'compositor_gl.cc',
         'compositor.h',
+        'compositor_gl.cc',
       ],
       'conditions': [
         ['OS=="linux" or OS=="freebsd" or OS=="openbsd"', {
           'sources!': [
             'compositor.cc',
           ],
-        }, {
-          'sources!': [
-            'compositor_gl.cc',
-          ]
         }],
       ],
     },
   ],
-}
\ No newline at end of file
+}
diff --git a/ui/gfx/compositor/compositor.h b/ui/gfx/compositor/compositor.h
index 7d19598..9b35eb1 100644
--- a/ui/gfx/compositor/compositor.h
+++ b/ui/gfx/compositor/compositor.h
@@ -9,9 +9,16 @@
 #include "base/memory/ref_counted.h"
 #include "ui/gfx/native_widget_types.h"
 
+class SkBitmap;
+namespace gfx {
+class Point;
+class Size;
+}
+
 namespace ui {
 class Transform;
 
+#if !defined(COMPOSITOR_2)
 typedef unsigned int TextureID;
 
 // Compositor object to take care of GPU painting.
@@ -48,6 +55,56 @@ class Compositor : public base::RefCounted<Compositor> {
   friend class base::RefCounted<Compositor>;
 };
 
+#else
+// Textures are created by a Compositor for managing an accelerated view.
+// Any time a View with a texture needs to redraw itself it invokes SetBitmap().
+// When the view is ready to be drawn Draw() is invoked.
+//
+// Texture is really a proxy to the gpu. Texture does not itself keep a copy of
+// the bitmap.
+//
+// Views own the Texture.
+class Texture {
+ public:
+  virtual ~Texture() {}
+
+  // Sets the bitmap of this texture. The bitmaps origin is at |origin|.
+  // |overall_size| gives the total size of texture.
+  virtual void SetBitmap(const SkBitmap& bitmap,
+                         const gfx::Point& origin,
+                         const gfx::Size& overall_size) = 0;
+
+  // Draws the texture.
+  virtual void Draw(const ui::Transform& transform) = 0;
+};
+
+// Compositor object to take care of GPU painting.
+// A Browser compositor object is responsible for generating the final
+// displayable form of pixels comprising a single widget's contents. It draws an
+// appropriately transformed texture for each transformed view in the widget's
+// view hierarchy.
+class Compositor : public base::RefCounted<Compositor> {
+ public:
+  // Create a compositor from the provided handle.
+  static Compositor* Create(gfx::AcceleratedWidget widget);
+
+  // Creates a new texture. The caller owns the returned object.
+  virtual Texture* CreateTexture() = 0;
+
+  // Notifies the compositor that compositing is about to start.
+  virtual void NotifyStart() = 0;
+
+  // Notifies the compositor that compositing is complete.
+  virtual void NotifyEnd() = 0;
+
+ protected:
+  virtual ~Compositor() {}
+
+ private:
+  friend class base::RefCounted<Compositor>;
+};
+
+#endif  // COMPOSITOR_2
 }  // namespace ui
 
 #endif  // UI_GFX_COMPOSITOR_COMPOSITOR_H_
diff --git a/ui/gfx/compositor/compositor_gl.cc b/ui/gfx/compositor/compositor_gl.cc
index f152ffc..4beb65c 100644
--- a/ui/gfx/compositor/compositor_gl.cc
+++ b/ui/gfx/compositor/compositor_gl.cc
@@ -15,6 +15,57 @@
 
 namespace ui {
 
+#if defined COMPOSITOR_2
+namespace {
+
+class CompositorGL : public Compositor {
+ public:
+  explicit CompositorGL(gfx::AcceleratedWidget widget);
+
+ private:
+  // Overridden from Compositor.
+  virtual Texture* CreateTexture() OVERRIDE;
+  virtual void NotifyStart() OVERRIDE;
+  virtual void NotifyEnd() OVERRIDE;
+
+  // The GL context used for compositing.
+  scoped_ptr<gfx::GLContext> gl_context_;
+
+  // Keep track of whether compositing has started or not.
+  bool started_;
+
+  DISALLOW_COPY_AND_ASSIGN(CompositorGL);
+};
+
+CompositorGL::CompositorGL(gfx::AcceleratedWidget widget)
+    : gl_context_(gfx::GLContext::CreateViewGLContext(widget, false)),
+      started_(false) {
+}
+
+Texture* CompositorGL::CreateTexture() {
+  return NULL;
+}
+
+void CompositorGL::NotifyStart() {
+  started_ = true;
+  gl_context_->MakeCurrent();
+}
+
+void CompositorGL::NotifyEnd() {
+  DCHECK(started_);
+  gl_context_->SwapBuffers();
+  started_ = false;
+}
+
+}  // namespace
+
+// static
+Compositor* Compositor::Create(gfx::AcceleratedWidget widget) {
+  if (gfx::GetGLImplementation() != gfx::kGLImplementationNone)
+    return new CompositorGL(widget);
+  return NULL;
+}
+#else
 class CompositorGL : public Compositor {
  public:
   explicit CompositorGL(gfx::AcceleratedWidget widget);
@@ -77,5 +128,5 @@ Compositor* Compositor::Create(gfx::AcceleratedWidget widget) {
     return new CompositorGL(widget);
   return NULL;
 }
-
+#endif
 }  // namespace ui