Enable texture readback support for Android

- Adjust the GLHelper to include methods we can use for our texture readback support.
- Tie it into the RenderWidgetHostViewAndroid/ContentViewCore/Compositor.

BUG=


Review URL: https://chromiumcodereview.appspot.com/11234008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@163455 0039d316-1c4b-4281-b951-d872f2087c98

4 files changed, 29 insertions, 9 deletions

diff --git a/content/public/android/java/src/org/chromium/content/browser/ContentView.java b/content/public/android/java/src/org/chromium/content/browser/ContentView.java
index b9046b3..55616a7 100644
--- a/content/public/android/java/src/org/chromium/content/browser/ContentView.java
+++ b/content/public/android/java/src/org/chromium/content/browser/ContentView.java
@@ -312,11 +312,7 @@ public class ContentView extends FrameLayout implements ContentViewCore.Internal
     }
 
     public Bitmap getBitmap(int width, int height) {
-        return getBitmap(width, height, Bitmap.Config.ARGB_8888);
-    }
-
-    public Bitmap getBitmap(int width, int height, Bitmap.Config config) {
-        return mContentViewCore.getBitmap(width, height, config);
+        return mContentViewCore.getBitmap(width, height);
     }
 
     /**
diff --git a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
index ff037b0..5941d8d 100644
--- a/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
+++ b/content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java
@@ -710,11 +710,23 @@ public class ContentViewCore implements MotionEventDelegate {
     }
 
     public Bitmap getBitmap(int width, int height) {
-        return getBitmap(width, height, Bitmap.Config.ARGB_8888);
-    }
+        if (getWidth() == 0 || getHeight() == 0) return null;
+
+        Bitmap b = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
+
+        if (mNativeContentViewCore != 0 &&
+                nativePopulateBitmapFromCompositor(mNativeContentViewCore, b)) {
+            // If we successfully grabbed a bitmap, check if we have to draw the Android overlay
+            // components as well.
+            if (mContainerView.getParent() != null &&
+                    mContainerView.getVisibility() == View.VISIBLE) {
+                Canvas c = new Canvas(b);
+                c.scale(width / (float) getWidth(), height / (float) getHeight());
+                mContainerView.draw(c);
+            }
+            return b;
+        }
 
-    public Bitmap getBitmap(int width, int height, Bitmap.Config config) {
-        // TODO(nileshagrawal): Implement this.
         return null;
     }
 
@@ -2203,4 +2215,7 @@ public class ContentViewCore implements MotionEventDelegate {
 
     private native void nativeUpdateVSyncParameters(int nativeContentViewCoreImpl,
             long timebaseMicros, long intervalMicros);
+
+    private native boolean nativePopulateBitmapFromCompositor(int nativeContentViewCoreImpl,
+            Bitmap bitmap);
 }
diff --git a/content/public/browser/android/compositor.h b/content/public/browser/android/compositor.h
index 33da403..721b5fd 100644
--- a/content/public/browser/android/compositor.h
+++ b/content/public/browser/android/compositor.h
@@ -73,6 +73,10 @@ class Compositor {
   // Deletes an OpenGL texture.
   virtual void DeleteTexture(WebKit::WebGLId texture_id) = 0;
 
+  // Grabs a copy of |texture_id| and saves it into |bitmap|.  No scaling is
+  // done.  It is assumed that the texture size matches that of the bitmap.
+  virtual void CopyTextureToBitmap(WebKit::WebGLId texture_id,
+                                   gfx::JavaBitmap& bitmap) = 0;
  protected:
   Compositor() {}
 };
diff --git a/content/public/browser/android/content_view_core.h b/content/public/browser/android/content_view_core.h
index fdb98c3..bce865f 100644
--- a/content/public/browser/android/content_view_core.h
+++ b/content/public/browser/android/content_view_core.h
@@ -10,6 +10,10 @@
 
 #include "content/public/browser/navigation_controller.h"
 
+namespace gfx {
+class Size;
+}
+
 namespace ui {
 class WindowAndroid;
 }
@@ -33,6 +37,7 @@ class ContentViewCore {
   virtual void OnWebPreferencesUpdated() = 0;
   virtual jint GetCurrentRenderProcessId(JNIEnv* env, jobject obj) = 0;
   virtual void ShowPastePopup(int x, int y) = 0;
+  virtual unsigned int GetScaledContentTexture(const gfx::Size& size) = 0;
 
  protected:
   virtual ~ContentViewCore() {};