Add RGB565 Texture readback support in gl_helper

content/browser/renderer_host/render_widget_host_view_android.cc

 // Copyright (c) 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.
 
 #include "content/browser/renderer_host/render_widget_host_view_android.h"
 
 #include <android/bitmap.h>
 
 #include "base/basictypes.h"
 #include "base/bind.h"
@@ skipping 245 matching lines @@
 }
 
 bool RenderWidgetHostViewAndroid::PopulateBitmapWithContents(jobject jbitmap) {
   if (!CompositorImpl::IsInitialized() ||
       texture_id_in_layer_ == 0 ||
       texture_size_in_layer_.IsEmpty())
     return false;
 
   gfx::JavaBitmap bitmap(jbitmap);
 
-  // TODO(dtrainor): Eventually add support for multiple formats here.
-  DCHECK(bitmap.format() == ANDROID_BITMAP_FORMAT_RGBA_8888);
+  DCHECK((bitmap.format() == ANDROID_BITMAP_FORMAT_RGBA_8888) ||
+    (bitmap.format() == ANDROID_BITMAP_FORMAT_RGB_565));
+
+  SkBitmap rgba_bitmap;
+  void* jbitmap_buffer = NULL;
+  void* gl_read_pass_buffer = NULL;
+
+  const gfx::Rect& bitmap_rect = gfx::Rect(bitmap.size());
+  int bitmap_width = bitmap_rect.width();
+  int bitmap_height = bitmap_rect.height();
+  jbitmap_buffer = reinterpret_cast<void*> (bitmap.pixels());
+
+  switch (bitmap.format()) {
+    case ANDROID_BITMAP_FORMAT_RGBA_8888:
+      gl_read_pass_buffer = jbitmap_buffer;
+      break;
+    case ANDROID_BITMAP_FORMAT_RGB_565:
+      rgba_bitmap.setConfig(SkBitmap::kARGB_8888_Config,
+                            bitmap_width,
+                            bitmap_height);
+      rgba_bitmap.allocPixels();
+      gl_read_pass_buffer = rgba_bitmap.getPixels();
+      break;
+    default:
+      NOTREACHED();
+      break;
+  }
 
   GLHelper* helper = ImageTransportFactoryAndroid::GetInstance()->GetGLHelper();
 
   blink::WebGLId texture = helper->CopyAndScaleTexture(
       texture_id_in_layer_,
       texture_size_in_layer_,
       bitmap.size(),
       true,
       GLHelper::SCALER_QUALITY_FAST);
   if (texture == 0)
     return false;
 
   helper->ReadbackTextureSync(texture,
-                              gfx::Rect(bitmap.size()),
-                              static_cast<unsigned char*> (bitmap.pixels()));
+    gfx::Rect(bitmap.size()),
+    static_cast<unsigned char*> (gl_read_pass_buffer));
 
   blink::WebGraphicsContext3D* context =
       ImageTransportFactoryAndroid::GetInstance()->GetContext3D();
   context->deleteTexture(texture);
 
+  if(bitmap.format() == ANDROID_BITMAP_FORMAT_RGB_565){
+    SkBitmap rgb565_bitmap;
+    rgb565_bitmap.setConfig(SkBitmap::kRGB_565_Config,
+                            bitmap_width,
+                            bitmap_height, 0);
+    rgb565_bitmap.setPixels(jbitmap_buffer);
+    SkCanvas rgb565_canvas(rgb565_bitmap);
+    SkRect draw_rect = SkRect::MakeXYWH(SkIntToScalar(0),
+                                        SkIntToScalar(0),
+                                        SkIntToScalar(bitmap_width),
+                                        SkIntToScalar(bitmap_height));
+
+    rgb565_canvas.drawBitmapRectToRect(rgba_bitmap,
+                                       &draw_rect,

[no sievers, 2013/11/26 21:45:27]

Isn't the point of this to reduce the readback size?
This just seems to add another CPU copy and conversion. And the API for this is
unnecessary here, since the app might just do that itself.

+                                       draw_rect,
+                                       NULL);
+  }
+
   return true;
 }
 
 bool RenderWidgetHostViewAndroid::HasValidFrame() const {
   if (!content_view_core_)
     return false;
   if (texture_size_in_layer_.IsEmpty())
     return false;
 
   if (UsingDelegatedRenderer()) {
@@ skipping 1078 matching lines @@
 // RenderWidgetHostView, public:
 
 // static
 RenderWidgetHostView*
 RenderWidgetHostView::CreateViewForWidget(RenderWidgetHost* widget) {
   RenderWidgetHostImpl* rwhi = RenderWidgetHostImpl::From(widget);
   return new RenderWidgetHostViewAndroid(rwhi, NULL);
 }
 
 } // namespace content