Implement transform/clip support for Android WebView.

cc/output/direct_renderer.cc

 // 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.
 
 #include "cc/output/direct_renderer.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/debug/trace_event.h"
@@ skipping 62 matching lines @@
                                        const gfx::Transform& quad_transform,
                                        const gfx::RectF& quad_rect) {
   *quad_rect_transform = quad_transform;
   quad_rect_transform->Translate(0.5 * quad_rect.width() + quad_rect.x(),
                                  0.5 * quad_rect.height() + quad_rect.y());
   quad_rect_transform->Scale(quad_rect.width(), quad_rect.height());
 }
 
 // static
 void DirectRenderer::InitializeMatrices(DrawingFrame* frame,
+                                        gfx::Vector2d offset,
                                         gfx::Rect draw_rect,
                                         bool flip_y) {
   if (flip_y) {
     frame->projection_matrix = OrthoProjectionMatrix(draw_rect.x(),
                                                      draw_rect.right(),
                                                      draw_rect.bottom(),
                                                      draw_rect.y());
   } else {
     frame->projection_matrix = OrthoProjectionMatrix(draw_rect.x(),
                                                      draw_rect.right(),
                                                      draw_rect.y(),
                                                      draw_rect.bottom());
   }
-  frame->window_matrix =
-      window_matrix(0, 0, draw_rect.width(), draw_rect.height());
+
+  frame->window_matrix = window_matrix(
+      offset.x(), offset.y(), draw_rect.width(), draw_rect.height());
   frame->flipped_y = flip_y;
 }
 
-// static
 gfx::Rect DirectRenderer::MoveScissorToWindowSpace(
     const DrawingFrame* frame, const gfx::RectF& scissor_rect) {
   gfx::Rect scissor_rect_in_canvas_space = gfx::ToEnclosingRect(scissor_rect);
   // The scissor coordinates must be supplied in viewport space so we need to
   // offset by the relative position of the top left corner of the current
   // render pass.
   gfx::Rect framebuffer_output_rect = frame->current_render_pass->output_rect;
   scissor_rect_in_canvas_space.set_x(
       scissor_rect_in_canvas_space.x() - framebuffer_output_rect.x());
   if (frame->flipped_y && !frame->current_texture) {
     scissor_rect_in_canvas_space.set_y(
         framebuffer_output_rect.height() -
         (scissor_rect_in_canvas_space.bottom() - framebuffer_output_rect.y()));
   } else {
     scissor_rect_in_canvas_space.set_y(
         scissor_rect_in_canvas_space.y() - framebuffer_output_rect.y());
   }
+  if (!frame->current_texture)
+    scissor_rect_in_canvas_space.Offset(client_->DeviceViewportOffset());
   return scissor_rect_in_canvas_space;
 }
 
 DirectRenderer::DirectRenderer(RendererClient* client,
                                ResourceProvider* resource_provider)
     : Renderer(client),
       resource_provider_(resource_provider) {}
 
 DirectRenderer::~DirectRenderer() {}
 
@@ skipping 187 matching lines @@
   }
 }
 
 bool DirectRenderer::UseRenderPass(DrawingFrame* frame,
                                    const RenderPass* render_pass) {
   frame->current_render_pass = render_pass;
   frame->current_texture = NULL;
 
   if (render_pass == frame->root_render_pass) {
     BindFramebufferToOutputSurface(frame);
-    InitializeMatrices(frame, render_pass->output_rect, FlippedFramebuffer());
-    SetDrawViewportSize(render_pass->output_rect.size());
+    InitializeMatrices(frame,
+                       client_->DeviceViewportOffset(),
+                       render_pass->output_rect,
+                       FlippedFramebuffer());
+    SetDrawViewport(
+        gfx::Rect(gfx::PointAtOffsetFromOrigin(client_->DeviceViewportOffset()),
+                  render_pass->output_rect.size()));
     return true;
   }
 
   if (!resource_provider_)
     return false;
 
   CachedResource* texture = render_pass_textures_.get(render_pass->id);
   DCHECK(texture);
 
   gfx::Size size = RenderPassTextureSize(render_pass);
@@ skipping 21 matching lines @@
 gfx::Size DirectRenderer::RenderPassTextureSize(const RenderPass* render_pass) {
   return render_pass->output_rect.size();
 }
 
 // static
 GLenum DirectRenderer::RenderPassTextureFormat(const RenderPass* render_pass) {
   return GL_RGBA;
 }
 
 }  // namespace cc