Splitting of layers for correct intersections

cc/output/gl_renderer.cc

 // Copyright 2010 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/gl_renderer.h"
 
 #include <algorithm>
 #include <limits>
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/strings/string_split.h"
+#include "base/strings/string_util.h"
+#include "base/strings/stringprintf.h"
+#include "build/build_config.h"
 #include "cc/base/math_util.h"
 #include "cc/layers/video_layer_impl.h"
 #include "cc/output/compositor_frame.h"
 #include "cc/output/compositor_frame_metadata.h"
 #include "cc/output/context_provider.h"
 #include "cc/output/copy_output_request.h"
 #include "cc/output/geometry_binding.h"
 #include "cc/output/gl_frame_data.h"
 #include "cc/output/output_surface.h"
 #include "cc/output/render_surface_filters.h"
+#include "cc/quads/draw_polygon.h"
 #include "cc/quads/picture_draw_quad.h"
 #include "cc/quads/render_pass.h"
 #include "cc/quads/stream_video_draw_quad.h"
 #include "cc/quads/texture_draw_quad.h"
 #include "cc/resources/layer_quad.h"
 #include "cc/resources/scoped_gpu_raster.h"
 #include "cc/resources/scoped_resource.h"
 #include "cc/resources/texture_mailbox_deleter.h"
 #include "gpu/GLES2/gl2extchromium.h"
 #include "gpu/command_buffer/client/context_support.h"
@@ skipping 282 matching lines @@
       context_support_(output_surface->context_provider()->ContextSupport()),
       texture_mailbox_deleter_(texture_mailbox_deleter),
       is_backbuffer_discarded_(false),
       is_scissor_enabled_(false),
       scissor_rect_needs_reset_(true),
       stencil_shadow_(false),
       blend_shadow_(false),
       highp_threshold_min_(highp_threshold_min),
       highp_threshold_cache_(0),
       use_sync_query_(false),
-      on_demand_tile_raster_resource_id_(0) {
+      on_demand_tile_raster_resource_id_(0),
+      bound_geometry_(NoBinding) {
   DCHECK(gl_);
   DCHECK(context_support_);
 
   ContextProvider::Capabilities context_caps =
       output_surface_->context_provider()->ContextCapabilities();
 
   capabilities_.using_partial_swap =
       settings_->partial_swap_enabled && context_caps.gpu.post_sub_buffer;
 
   DCHECK(!context_caps.gpu.iosurface || context_caps.gpu.texture_rectangle);
@@ skipping 149 matching lines @@
 
   // TODO(enne): Do we need to reinitialize all of this state per frame?
   ReinitializeGLState();
 }
 
 void GLRenderer::DoNoOp() {
   GLC(gl_, gl_->BindFramebuffer(GL_FRAMEBUFFER, 0));
   GLC(gl_, gl_->Flush());
 }
 
-void GLRenderer::DoDrawQuad(DrawingFrame* frame, const DrawQuad* quad) {
+void GLRenderer::DoDrawQuad(DrawingFrame* frame,
+                            const DrawQuad* quad,
+                            const gfx::QuadF* draw_region) {
   DCHECK(quad->rect.Contains(quad->visible_rect));
   if (quad->material != DrawQuad::TEXTURE_CONTENT) {
-    FlushTextureQuadCache();
+    FlushTextureQuadCache(false);
   }
 
   switch (quad->material) {
     case DrawQuad::INVALID:
       NOTREACHED();
       break;
     case DrawQuad::CHECKERBOARD:
-      DrawCheckerboardQuad(frame, CheckerboardDrawQuad::MaterialCast(quad));
+      DrawCheckerboardQuad(frame, CheckerboardDrawQuad::MaterialCast(quad),
+                           draw_region);
       break;
     case DrawQuad::DEBUG_BORDER:
       DrawDebugBorderQuad(frame, DebugBorderDrawQuad::MaterialCast(quad));
       break;
     case DrawQuad::IO_SURFACE_CONTENT:
-      DrawIOSurfaceQuad(frame, IOSurfaceDrawQuad::MaterialCast(quad));
+      DrawIOSurfaceQuad(frame, IOSurfaceDrawQuad::MaterialCast(quad),
+                        draw_region);
       break;
     case DrawQuad::PICTURE_CONTENT:
-      DrawPictureQuad(frame, PictureDrawQuad::MaterialCast(quad));
+      DrawPictureQuad(frame, PictureDrawQuad::MaterialCast(quad), draw_region);
       break;
     case DrawQuad::RENDER_PASS:
-      DrawRenderPassQuad(frame, RenderPassDrawQuad::MaterialCast(quad));
+      DrawRenderPassQuad(frame, RenderPassDrawQuad::MaterialCast(quad),
+                         draw_region);
       break;
     case DrawQuad::SOLID_COLOR:
-      DrawSolidColorQuad(frame, SolidColorDrawQuad::MaterialCast(quad));
+      DrawSolidColorQuad(frame, SolidColorDrawQuad::MaterialCast(quad),
+                         draw_region);
       break;
     case DrawQuad::STREAM_VIDEO_CONTENT:
-      DrawStreamVideoQuad(frame, StreamVideoDrawQuad::MaterialCast(quad));
+      DrawStreamVideoQuad(frame, StreamVideoDrawQuad::MaterialCast(quad),
+                          draw_region);
       break;
     case DrawQuad::SURFACE_CONTENT:
       // Surface content should be fully resolved to other quad types before
       // reaching a direct renderer.
       NOTREACHED();
       break;
     case DrawQuad::TEXTURE_CONTENT:
-      EnqueueTextureQuad(frame, TextureDrawQuad::MaterialCast(quad));
+      EnqueueTextureQuad(frame, TextureDrawQuad::MaterialCast(quad),
+                         draw_region);
       break;
     case DrawQuad::TILED_CONTENT:
-      DrawTileQuad(frame, TileDrawQuad::MaterialCast(quad));
+      DrawTileQuad(frame, TileDrawQuad::MaterialCast(quad), draw_region);
       break;
     case DrawQuad::YUV_VIDEO_CONTENT:
-      DrawYUVVideoQuad(frame, YUVVideoDrawQuad::MaterialCast(quad));
+      DrawYUVVideoQuad(frame, YUVVideoDrawQuad::MaterialCast(quad),
+                       draw_region);
       break;
   }
 }
 
 void GLRenderer::DrawCheckerboardQuad(const DrawingFrame* frame,
-                                      const CheckerboardDrawQuad* quad) {
+                                      const CheckerboardDrawQuad* quad,
+                                      const gfx::QuadF* clip_region) {
+  // TODO(thildebr) For now since checkerboards shouldn't be part of a 3D
+  // context, clipping regions aren't supported so we skip drawing them
+  // if this becomes the case.
+  if (clip_region) {
+    return;
+  }
   SetBlendEnabled(quad->ShouldDrawWithBlending());
 
   const TileCheckerboardProgram* program = GetTileCheckerboardProgram();
   DCHECK(program && (program->initialized() || IsContextLost()));
   SetUseProgram(program->program());
 
   SkColor color = quad->color;
   GLC(gl_,
       gl_->Uniform4f(program->fragment_shader().color_location(),
                      SkColorGetR(color) * (1.0f / 255.0f),
@@ skipping 21 matching lines @@
                      frequency));
 
   SetShaderOpacity(quad->opacity(),
                    program->fragment_shader().alpha_location());
   DrawQuadGeometry(frame,
                    quad->quadTransform(),
                    quad->rect,
                    program->vertex_shader().matrix_location());
 }
 
+// This function does not handle 3D sorting right now, since the debug border
+// quads are just drawn as their original quads and not in split pieces. This
+// results in some debug border quads drawing over foreground quads.
 void GLRenderer::DrawDebugBorderQuad(const DrawingFrame* frame,
                                      const DebugBorderDrawQuad* quad) {
   SetBlendEnabled(quad->ShouldDrawWithBlending());
 
   static float gl_matrix[16];
   const DebugBorderProgram* program = GetDebugBorderProgram();
   DCHECK(program && (program->initialized() || IsContextLost()));
   SetUseProgram(program->program());
 
   // Use the full quad_rect for debug quads to not move the edges based on
@@ skipping 206 matching lines @@
   if (frame->current_render_pass->has_transparent_background)
     return false;
 
   // TODO(ajuma): Add support for reference filters once
   // FilterOperations::GetOutsets supports reference filters.
   if (quad->background_filters.HasReferenceFilter())
     return false;
   return true;
 }
 
+bool GetScaledRegion(const gfx::Rect& rect,

[enne (OOO), 2015/02/04 21:24:00]

This function needs a comment about what it's doing.

[awoloszyn, 2015/02/12 16:48:51]

Done.

+                     const gfx::QuadF* clip,
+                     gfx::QuadF* scaled_region) {
+  if (clip) {
+    gfx::PointF p1(((clip->p1().x() - rect.x()) / rect.width()) - 0.5f,
+                   ((clip->p1().y() - rect.y()) / rect.height()) - 0.5f);
+    gfx::PointF p2(((clip->p2().x() - rect.x()) / rect.width()) - 0.5f,
+                   ((clip->p2().y() - rect.y()) / rect.height()) - 0.5f);
+    gfx::PointF p3(((clip->p3().x() - rect.x()) / rect.width()) - 0.5f,
+                   ((clip->p3().y() - rect.y()) / rect.height()) - 0.5f);
+    gfx::PointF p4(((clip->p4().x() - rect.x()) / rect.width()) - 0.5f,
+                   ((clip->p4().y() - rect.y()) / rect.height()) - 0.5f);
+    *scaled_region = gfx::QuadF(p1, p2, p3, p4);
+    return true;
+  }
+  return false;
+}
+
 gfx::Rect GLRenderer::GetBackdropBoundingBoxForRenderPassQuad(
     DrawingFrame* frame,
     const RenderPassDrawQuad* quad,
     const gfx::Transform& contents_device_transform,
+    const gfx::QuadF* clip_region,
     bool use_aa) {
+  gfx::QuadF scaled_region;
+  if (!GetScaledRegion(quad->rect, clip_region, &scaled_region)) {
+    scaled_region = SharedGeometryQuad().BoundingBox();
+  }
+
   gfx::Rect backdrop_rect = gfx::ToEnclosingRect(MathUtil::MapClippedRect(
-      contents_device_transform, SharedGeometryQuad().BoundingBox()));
+      contents_device_transform, scaled_region.BoundingBox()));
 
   if (ShouldApplyBackgroundFilters(frame, quad)) {
     int top, right, bottom, left;
     quad->background_filters.GetOutsets(&top, &right, &bottom, &left);
     backdrop_rect.Inset(-left, -top, -right, -bottom);
   }
 
   if (!backdrop_rect.IsEmpty() && use_aa) {
     const int kOutsetForAntialiasing = 1;
     backdrop_rect.Inset(-kOutsetForAntialiasing, -kOutsetForAntialiasing);
@@ skipping 32 matching lines @@
       ApplyImageFilter(ScopedUseGrContext::Create(this, frame),
                        resource_provider_,
                        quad->rect.origin(),
                        quad->filters_scale,
                        filter.get(),
                        background_texture);
   return background_with_filters;
 }
 
 void GLRenderer::DrawRenderPassQuad(DrawingFrame* frame,
-                                    const RenderPassDrawQuad* quad) {
+                                    const RenderPassDrawQuad* quad,
+                                    const gfx::QuadF* clip_region) {
   ScopedResource* contents_texture =
       render_pass_textures_.get(quad->render_pass_id);
   if (!contents_texture || !contents_texture->id())
     return;
 
   gfx::Transform quad_rect_matrix;
   QuadRectTransform(&quad_rect_matrix, quad->quadTransform(), quad->rect);
   gfx::Transform contents_device_transform =
       frame->window_matrix * frame->projection_matrix * quad_rect_matrix;
   contents_device_transform.FlattenTo2d();
 
   // Can only draw surface if device matrix is invertible.
   if (!contents_device_transform.IsInvertible())
     return;
 
   gfx::QuadF surface_quad = SharedGeometryQuad();
   float edge[24];
   bool use_aa = settings_->allow_antialiasing &&
                 ShouldAntialiasQuad(contents_device_transform, quad,
                                     settings_->force_antialiasing);
 
-  if (use_aa)
-    SetupQuadForAntialiasing(contents_device_transform, quad,
-                             &surface_quad, edge);
-
+  SetupQuadForClippingAndAntialiasing(contents_device_transform, quad, use_aa,
+                                      clip_region, &surface_quad, edge);
   SkXfermode::Mode blend_mode = quad->shared_quad_state->blend_mode;
   bool use_shaders_for_blending =
       !CanApplyBlendModeUsingBlendFunc(blend_mode) ||
       ShouldApplyBackgroundFilters(frame, quad) ||
       settings_->force_blending_with_shaders;
 
   scoped_ptr<ScopedResource> background_texture;
   skia::RefPtr<SkImage> background_image;
   gfx::Rect background_rect;
   if (use_shaders_for_blending) {
     // Compute a bounding box around the pixels that will be visible through
     // the quad.
     background_rect = GetBackdropBoundingBoxForRenderPassQuad(
-        frame, quad, contents_device_transform, use_aa);
+        frame, quad, contents_device_transform, clip_region, use_aa);
 
     if (!background_rect.IsEmpty()) {
       // The pixels from the filtered background should completely replace the
       // current pixel values.
       if (blend_enabled())
         SetBlendEnabled(false);
 
       // Read the pixels in the bounding box into a buffer R.
       // This function allocates a texture, which should contribute to the
       // amount of memory used by render surfaces:
@@ skipping 405 matching lines @@
 static void SolidColorUniformLocation(T program,
                                       SolidColorProgramUniforms* uniforms) {
   uniforms->program = program->program();
   uniforms->matrix_location = program->vertex_shader().matrix_location();
   uniforms->viewport_location = program->vertex_shader().viewport_location();
   uniforms->quad_location = program->vertex_shader().quad_location();
   uniforms->edge_location = program->vertex_shader().edge_location();
   uniforms->color_location = program->fragment_shader().color_location();
 }
 
+bool is_top(const gfx::QuadF* clip_region, const DrawQuad* quad) {
+  if (!quad->IsTopEdge())
+    return false;
+  if (!clip_region) {
+    return true;
+  }
+  return std::abs(clip_region->p1().y()) < kAntiAliasingEpsilon &&
+         std::abs(clip_region->p2().y()) < kAntiAliasingEpsilon;
+}
+
+bool is_bottom(const gfx::QuadF* clip_region, const DrawQuad* quad) {
+  if (!quad->IsBottomEdge())
+    return false;
+  if (!clip_region) {
+    return true;
+  }
+  return std::abs(clip_region->p3().y() -
+                  quad->shared_quad_state->content_bounds.height()) <
+             kAntiAliasingEpsilon &&
+         std::abs(clip_region->p4().y() -
+                  quad->shared_quad_state->content_bounds.height()) <
+             kAntiAliasingEpsilon;
+}
+
+bool is_left(const gfx::QuadF* clip_region, const DrawQuad* quad) {
+  if (!quad->IsLeftEdge())
+    return false;
+  if (!clip_region) {
+    return true;
+  }
+  return std::abs(clip_region->p1().x()) < kAntiAliasingEpsilon &&
+         std::abs(clip_region->p4().x()) < kAntiAliasingEpsilon;
+}
+
+bool is_right(const gfx::QuadF* clip_region, const DrawQuad* quad) {
+  if (!quad->IsRightEdge())
+    return false;
+  if (!clip_region) {
+    return true;
+  }
+  return std::abs(clip_region->p2().x() -
+                  quad->shared_quad_state->content_bounds.width()) <
+             kAntiAliasingEpsilon &&
+         std::abs(clip_region->p3().x() -
+                  quad->shared_quad_state->content_bounds.width()) <
+             kAntiAliasingEpsilon;
+}
+
 static gfx::QuadF GetDeviceQuadWithAntialiasingOnExteriorEdges(
     const LayerQuad& device_layer_edges,
     const gfx::Transform& device_transform,
+    const gfx::QuadF* clip_region,
     const DrawQuad* quad) {
-  gfx::Rect tile_rect = quad->visible_rect;
-  gfx::PointF bottom_right = tile_rect.bottom_right();
-  gfx::PointF bottom_left = tile_rect.bottom_left();
-  gfx::PointF top_left = tile_rect.origin();
-  gfx::PointF top_right = tile_rect.top_right();
+  gfx::RectF tile_rect = quad->visible_rect;
+  gfx::QuadF tile_quad(tile_rect);
+
+  if (clip_region) {
+    if (quad->material != DrawQuad::RENDER_PASS) {
+      tile_quad = *clip_region;
+    } else {
+      GetScaledRegion(quad->rect, clip_region, &tile_quad);
+    }
+  }
+
+  gfx::PointF bottom_right = tile_quad.p3();
+  gfx::PointF bottom_left = tile_quad.p4();
+  gfx::PointF top_left = tile_quad.p1();
+  gfx::PointF top_right = tile_quad.p2();
   bool clipped = false;
 
   // Map points to device space. We ignore |clipped|, since the result of
   // |MapPoint()| still produces a valid point to draw the quad with. When
   // clipped, the point will be outside of the viewport. See crbug.com/416367.
   bottom_right = MathUtil::MapPoint(device_transform, bottom_right, &clipped);
   bottom_left = MathUtil::MapPoint(device_transform, bottom_left, &clipped);
   top_left = MathUtil::MapPoint(device_transform, top_left, &clipped);
   top_right = MathUtil::MapPoint(device_transform, top_right, &clipped);
 
   LayerQuad::Edge bottom_edge(bottom_right, bottom_left);
   LayerQuad::Edge left_edge(bottom_left, top_left);
   LayerQuad::Edge top_edge(top_left, top_right);
   LayerQuad::Edge right_edge(top_right, bottom_right);
 
   // Only apply anti-aliasing to edges not clipped by culling or scissoring.
-  if (quad->IsTopEdge() && tile_rect.y() == quad->rect.y())
+  // If an edge is degenerate we do not want to replace it with a "proper" edge

[enne (OOO), 2015/02/04 21:24:00]

Oh!  Good catch.  I didn't think about that.

+  // as that will cause the quad to possibly expand is strange ways.
+  if (!top_edge.degenerate() && is_top(clip_region, quad) &&
+      tile_rect.y() == quad->rect.y()) {
     top_edge = device_layer_edges.top();
-  if (quad->IsLeftEdge() && tile_rect.x() == quad->rect.x())
+  }
+  if (!left_edge.degenerate() && is_left(clip_region, quad) &&
+      tile_rect.x() == quad->rect.x()) {
     left_edge = device_layer_edges.left();
-  if (quad->IsRightEdge() && tile_rect.right() == quad->rect.right())
+  }
+  if (!right_edge.degenerate() && is_right(clip_region, quad) &&
+      tile_rect.right() == quad->rect.right()) {
     right_edge = device_layer_edges.right();
-  if (quad->IsBottomEdge() && tile_rect.bottom() == quad->rect.bottom())
+  }
+  if (!bottom_edge.degenerate() && is_bottom(clip_region, quad) &&
+      tile_rect.bottom() == quad->rect.bottom()) {
     bottom_edge = device_layer_edges.bottom();
+  }
 
-  float sign = gfx::QuadF(tile_rect).IsCounterClockwise() ? -1 : 1;
+  float sign = tile_quad.IsCounterClockwise() ? -1 : 1;
   bottom_edge.scale(sign);
   left_edge.scale(sign);
   top_edge.scale(sign);
   right_edge.scale(sign);
 
   // Create device space quad.
   return LayerQuad(left_edge, top_edge, right_edge, bottom_edge).ToQuadF();
 }
 
+float GetTotalQuadError(const gfx::QuadF* clipped_quad,
+                        const gfx::QuadF* ideal_rect) {
+  return (clipped_quad->p1() - ideal_rect->p1()).LengthSquared() +
+         (clipped_quad->p2() - ideal_rect->p2()).LengthSquared() +
+         (clipped_quad->p3() - ideal_rect->p3()).LengthSquared() +
+         (clipped_quad->p4() - ideal_rect->p4()).LengthSquared();
+}
+
+// Attempt to rotate the clipped quad until it lines up the most
+// correctly. This is necessary because we check the edges of this
+// quad against the expected left/right/top/bottom for anti-aliasing.
+void RotateQuad(gfx::QuadF* clipped_quad) {

[enne (OOO), 2015/02/04 21:23:59]

Maybe call this RotateQuadToMatchBoudingQuad? (Or some other word than rotate,
given my comments elsewhere?)

[awoloszyn, 2015/02/12 16:48:51]

Done.

+  gfx::QuadF bounding_quad = gfx::QuadF(clipped_quad->BoundingBox());
+  size_t least_error = 0;
+  float least_error_amount = GetTotalQuadError(clipped_quad, &bounding_quad);
+  for (size_t i = 1; i < 4; ++i) {
+    clipped_quad->Rotate(1);
+    float new_error = GetTotalQuadError(clipped_quad, &bounding_quad);
+    if (new_error < least_error_amount) {
+      least_error = i;
+      least_error_amount = new_error;
+    }
+  }
+  clipped_quad->Rotate((least_error + 1) % 4);

[enne (OOO), 2015/02/04 21:24:00]

This maybe needs some explanation? Also, a unit test?

[awoloszyn, 2015/02/12 16:48:51]

Replaced this with a temporary, it is much clearer, and I expect better for
performance than having to rotate the quad some more.

+}
+
 // static
 bool GLRenderer::ShouldAntialiasQuad(const gfx::Transform& device_transform,
                                      const DrawQuad* quad,
                                      bool force_antialiasing) {
   bool is_render_pass_quad = (quad->material == DrawQuad::RENDER_PASS);
   // For render pass quads, |device_transform| already contains quad's rect.
   // TODO(rosca@adobe.com): remove branching on is_render_pass_quad
   // crbug.com/429702
   if (!is_render_pass_quad && !quad->IsEdge())
     return false;
@@ skipping 11 matching lines @@
   bool is_nearest_rect_within_epsilon =
       is_axis_aligned_in_target &&
       gfx::IsNearestRectWithinDistance(device_layer_quad.BoundingBox(),
                                        kAntiAliasingEpsilon);
   // AAing clipped quads is not supported by the code yet.
   bool use_aa = !clipped && !is_nearest_rect_within_epsilon;
   return use_aa || force_antialiasing;
 }
 
 // static
-void GLRenderer::SetupQuadForAntialiasing(
+void GLRenderer::SetupQuadForClippingAndAntialiasing(
     const gfx::Transform& device_transform,
     const DrawQuad* quad,
+    bool use_aa,
+    const gfx::QuadF* clip_region_,

[enne (OOO), 2015/02/04 21:24:00]

clip_region (no underscore)

[awoloszyn, 2015/02/12 16:48:51]

Done.

     gfx::QuadF* local_quad,
     float edge[24]) {
   bool is_render_pass_quad = (quad->material == DrawQuad::RENDER_PASS);
-  gfx::RectF content_rect =
-      is_render_pass_quad ? QuadVertexRect() : quad->visibleContentRect();
+  gfx::QuadF rotated_clip;
+  const gfx::QuadF* clip_region = clip_region_;
+  if (clip_region_) {
+    rotated_clip = *clip_region_;
+    RotateQuad(&rotated_clip);
+    clip_region = &rotated_clip;
+  }
 
+  gfx::QuadF content_rect = is_render_pass_quad
+                                ? gfx::QuadF(QuadVertexRect())
+                                : gfx::QuadF(quad->visibleContentRect());
+  if (!use_aa) {
+    if (clip_region) {
+      if (!is_render_pass_quad) {
+        content_rect = *clip_region;
+      } else {
+        GetScaledRegion(quad->rect, clip_region, &content_rect);
+      }
+      *local_quad = content_rect;
+    }
+    return;
+  }
   bool clipped = false;
   gfx::QuadF device_layer_quad =
-      MathUtil::MapQuad(device_transform, gfx::QuadF(content_rect), &clipped);
+      MathUtil::MapQuad(device_transform, content_rect, &clipped);
 
   LayerQuad device_layer_bounds(gfx::QuadF(device_layer_quad.BoundingBox()));
   device_layer_bounds.InflateAntiAliasingDistance();
 
   LayerQuad device_layer_edges(device_layer_quad);
   device_layer_edges.InflateAntiAliasingDistance();
 
   device_layer_edges.ToFloatArray(edge);
   device_layer_bounds.ToFloatArray(&edge[12]);
 
+  // If we have a clip_region then we are split, and therefore
+  // by necessity, at least one of our edges is not an external
+  // one.
   bool use_aa_on_all_four_edges =
-      is_render_pass_quad ||
-      (quad->IsTopEdge() && quad->IsLeftEdge() && quad->IsBottomEdge() &&
-       quad->IsRightEdge() && quad->visible_rect == quad->rect);
+      !clip_region &&
+      (is_render_pass_quad ||
+       (is_top(clip_region, quad) && is_left(clip_region, quad) &&
+        is_bottom(clip_region, quad) && is_right(clip_region, quad) &&
+        quad->visible_rect == quad->rect));
 
   gfx::QuadF device_quad =
       use_aa_on_all_four_edges
           ? device_layer_edges.ToQuadF()
           : GetDeviceQuadWithAntialiasingOnExteriorEdges(
-                device_layer_edges, device_transform, quad);
+                device_layer_edges, device_transform, clip_region, quad);
 
   // Map device space quad to local space. device_transform has no 3d
   // component since it was flattened, so we don't need to project.  We should
   // have already checked that the transform was uninvertible above.
   gfx::Transform inverse_device_transform(gfx::Transform::kSkipInitialization);
   bool did_invert = device_transform.GetInverse(&inverse_device_transform);
   DCHECK(did_invert);
   *local_quad =
       MathUtil::MapQuad(inverse_device_transform, device_quad, &clipped);
   // We should not DCHECK(!clipped) here, because anti-aliasing inflation may
   // cause device_quad to become clipped. To our knowledge this scenario does
   // not need to be handled differently than the unclipped case.
 }
 
 void GLRenderer::DrawSolidColorQuad(const DrawingFrame* frame,
-                                    const SolidColorDrawQuad* quad) {
+                                    const SolidColorDrawQuad* quad,
+                                    const gfx::QuadF* clip_region) {
   gfx::Rect tile_rect = quad->visible_rect;
 
   SkColor color = quad->color;
   float opacity = quad->opacity();
   float alpha = (SkColorGetA(color) * (1.0f / 255.0f)) * opacity;
 
   // Early out if alpha is small enough that quad doesn't contribute to output.
   if (alpha < std::numeric_limits<float>::epsilon() &&
       quad->ShouldDrawWithBlending())
     return;
 
   gfx::Transform device_transform =
       frame->window_matrix * frame->projection_matrix * quad->quadTransform();
   device_transform.FlattenTo2d();
   if (!device_transform.IsInvertible())
     return;
 
   bool force_aa = false;
   gfx::QuadF local_quad = gfx::QuadF(gfx::RectF(tile_rect));
   float edge[24];
   bool use_aa = settings_->allow_antialiasing &&
                 !quad->force_anti_aliasing_off &&
                 ShouldAntialiasQuad(device_transform, quad, force_aa);
+  SetupQuadForClippingAndAntialiasing(device_transform, quad, use_aa,
+                                      clip_region, &local_quad, edge);
 
   SolidColorProgramUniforms uniforms;
   if (use_aa) {
-    SetupQuadForAntialiasing(device_transform, quad, &local_quad, edge);
     SolidColorUniformLocation(GetSolidColorProgramAA(), &uniforms);
   } else {
     SolidColorUniformLocation(GetSolidColorProgram(), &uniforms);
   }
   SetUseProgram(uniforms.program);
 
   GLC(gl_,
       gl_->Uniform4f(uniforms.color_location,
                      (SkColorGetR(color) * (1.0f / 255.0f)) * alpha,
                      (SkColorGetG(color) * (1.0f / 255.0f)) * alpha,
@@ skipping 50 matching lines @@
   uniforms->vertex_tex_transform_location =
       program->vertex_shader().vertex_tex_transform_location();
 
   uniforms->sampler_location = program->fragment_shader().sampler_location();
   uniforms->alpha_location = program->fragment_shader().alpha_location();
   uniforms->fragment_tex_transform_location =
       program->fragment_shader().fragment_tex_transform_location();
 }
 
 void GLRenderer::DrawTileQuad(const DrawingFrame* frame,
-                              const TileDrawQuad* quad) {
-  DrawContentQuad(frame, quad, quad->resource_id);
+                              const TileDrawQuad* quad,
+                              const gfx::QuadF* clip_region) {
+  DrawContentQuad(frame, quad, quad->resource_id, clip_region);
 }
 
 void GLRenderer::DrawContentQuad(const DrawingFrame* frame,
                                  const ContentDrawQuadBase* quad,
-                                 ResourceProvider::ResourceId resource_id) {
+                                 ResourceProvider::ResourceId resource_id,
+                                 const gfx::QuadF* clip_region) {
   gfx::Transform device_transform =
       frame->window_matrix * frame->projection_matrix * quad->quadTransform();
   device_transform.FlattenTo2d();
 
   bool use_aa = settings_->allow_antialiasing &&
                 ShouldAntialiasQuad(device_transform, quad, false);
 
   // TODO(timav): simplify coordinate transformations in DrawContentQuadAA
   // similar to the way DrawContentQuadNoAA works and then consider
   // combining DrawContentQuadAA and DrawContentQuadNoAA into one method.
   if (use_aa)
-    DrawContentQuadAA(frame, quad, resource_id, device_transform);
+    DrawContentQuadAA(frame, quad, resource_id, device_transform, clip_region);
   else
-    DrawContentQuadNoAA(frame, quad, resource_id);
+    DrawContentQuadNoAA(frame, quad, resource_id, clip_region);
 }
 
 void GLRenderer::DrawContentQuadAA(const DrawingFrame* frame,
                                    const ContentDrawQuadBase* quad,
                                    ResourceProvider::ResourceId resource_id,
-                                   const gfx::Transform& device_transform) {
+                                   const gfx::Transform& device_transform,
+                                   const gfx::QuadF* clip_region) {
   if (!device_transform.IsInvertible())
     return;
 
   gfx::Rect tile_rect = quad->visible_rect;
 
   gfx::RectF tex_coord_rect = MathUtil::ScaleRectProportional(
       quad->tex_coord_rect, quad->rect, tile_rect);
   float tex_to_geom_scale_x = quad->rect.width() / quad->tex_coord_rect.width();
   float tex_to_geom_scale_y =
       quad->rect.height() / quad->tex_coord_rect.height();
@@ skipping 24 matching lines @@
   float vertex_tex_translate_y =
       -clamp_geom_rect.y() / clamp_geom_rect.height();
   float vertex_tex_scale_x = tile_rect.width() / clamp_geom_rect.width();
   float vertex_tex_scale_y = tile_rect.height() / clamp_geom_rect.height();
 
   TexCoordPrecision tex_coord_precision = TexCoordPrecisionRequired(
       gl_, &highp_threshold_cache_, highp_threshold_min_, quad->texture_size);
 
   gfx::QuadF local_quad = gfx::QuadF(gfx::RectF(tile_rect));
   float edge[24];
-  SetupQuadForAntialiasing(device_transform, quad, &local_quad, edge);
-
+  SetupQuadForClippingAndAntialiasing(device_transform, quad, true, clip_region,
+                                      &local_quad, edge);
   ResourceProvider::ScopedSamplerGL quad_resource_lock(
       resource_provider_, resource_id,
       quad->nearest_neighbor ? GL_NEAREST : GL_LINEAR);
   SamplerType sampler =
       SamplerTypeFromTextureTarget(quad_resource_lock.target());
 
   float fragment_tex_translate_x = clamp_tex_rect.x();
   float fragment_tex_translate_y = clamp_tex_rect.y();
   float fragment_tex_scale_x = clamp_tex_rect.width();
   float fragment_tex_scale_y = clamp_tex_rect.height();
@@ skipping 57 matching lines @@
   // it. This is why this centered rect is used and not the original quad_rect.
   gfx::RectF centered_rect(
       gfx::PointF(-0.5f * tile_rect.width(), -0.5f * tile_rect.height()),
       tile_rect.size());
   DrawQuadGeometry(
       frame, quad->quadTransform(), centered_rect, uniforms.matrix_location);
 }
 
 void GLRenderer::DrawContentQuadNoAA(const DrawingFrame* frame,
                                      const ContentDrawQuadBase* quad,
-                                     ResourceProvider::ResourceId resource_id) {
+                                     ResourceProvider::ResourceId resource_id,
+                                     const gfx::QuadF* clip_region) {
   gfx::RectF tex_coord_rect = MathUtil::ScaleRectProportional(
       quad->tex_coord_rect, quad->rect, quad->visible_rect);
   float tex_to_geom_scale_x = quad->rect.width() / quad->tex_coord_rect.width();
   float tex_to_geom_scale_y =
       quad->rect.height() / quad->tex_coord_rect.height();
 
   bool scaled = (tex_to_geom_scale_x != 1.f || tex_to_geom_scale_y != 1.f);
   GLenum filter =
       (scaled || !quad->quadTransform().IsIdentityOrIntegerTranslation()) &&
               !quad->nearest_neighbor
@@ skipping 53 matching lines @@
                      vertex_tex_scale_y));
 
   SetBlendEnabled(quad->ShouldDrawWithBlending());
 
   SetShaderOpacity(quad->opacity(), uniforms.alpha_location);
 
   // Pass quad coordinates to the uniform in the same order as GeometryBinding
   // does, then vertices will match the texture mapping in the vertex buffer.
   // The method SetShaderQuadF() changes the order of vertices and so it's
   // not used here.
-
-  gfx::RectF tile_rect = quad->visible_rect;
+  gfx::QuadF tile_rect(quad->visible_rect);
+  float width = quad->visible_rect.width();
+  float height = quad->visible_rect.height();
+  gfx::PointF top_left = quad->visible_rect.origin();
+  if (clip_region) {
+    tile_rect = *clip_region;
+    float gl_uv[8] = {
+        (tile_rect.p4().x() - top_left.x()) / width,
+        (tile_rect.p4().y() - top_left.y()) / height,
+        (tile_rect.p1().x() - top_left.x()) / width,
+        (tile_rect.p1().y() - top_left.y()) / height,
+        (tile_rect.p2().x() - top_left.x()) / width,
+        (tile_rect.p2().y() - top_left.y()) / height,
+        (tile_rect.p3().x() - top_left.x()) / width,
+        (tile_rect.p3().y() - top_left.y()) / height,
+    };
+    PrepareGeometry(ClippedBinding);
+    clipped_geometry_->InitializeCustomQuadWithUVs(
+        gfx::QuadF(quad->visible_rect), gl_uv);
+  } else {
+    PrepareGeometry(SharedBinding);
+  }
   float gl_quad[8] = {
-    tile_rect.x(),
-    tile_rect.bottom(),
-    tile_rect.x(),
-    tile_rect.y(),
-    tile_rect.right(),
-    tile_rect.y(),
-    tile_rect.right(),
-    tile_rect.bottom(),
+      tile_rect.p4().x(),
+      tile_rect.p4().y(),
+      tile_rect.p1().x(),
+      tile_rect.p1().y(),
+      tile_rect.p2().x(),
+      tile_rect.p2().y(),
+      tile_rect.p3().x(),
+      tile_rect.p3().y(),
   };
   GLC(gl_, gl_->Uniform2fv(uniforms.quad_location, 4, gl_quad));
 
   static float gl_matrix[16];
   ToGLMatrix(&gl_matrix[0], frame->projection_matrix * quad->quadTransform());
   GLC(gl_,
       gl_->UniformMatrix4fv(uniforms.matrix_location, 1, false, &gl_matrix[0]));
 
   GLC(gl_, gl_->DrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, 0));
 }
 
 void GLRenderer::DrawYUVVideoQuad(const DrawingFrame* frame,
-                                  const YUVVideoDrawQuad* quad) {
+                                  const YUVVideoDrawQuad* quad,
+                                  const gfx::QuadF* clip_region) {
   SetBlendEnabled(quad->ShouldDrawWithBlending());
 
   TexCoordPrecision tex_coord_precision = TexCoordPrecisionRequired(
       gl_,
       &highp_threshold_cache_,
       highp_threshold_min_,
       quad->shared_quad_state->visible_content_rect.bottom_right());
 
   bool use_alpha_plane = quad->a_plane_resource_id != 0;
 
@@ skipping 98 matching lines @@
     case YUVVideoDrawQuad::REC_601:
       yuv_to_rgb = yuv_to_rgb_rec601;
       yuv_adjust = yuv_adjust_rec601;
       break;
     case YUVVideoDrawQuad::REC_601_JPEG:
       yuv_to_rgb = yuv_to_rgb_rec601_jpeg;
       yuv_adjust = yuv_adjust_rec601_jpeg;
       break;
   }
 
+  // The transform and vertex data are used to figure out the extents that the
+  // un-antialiased quad should have and which vertex this is and the float
+  // quad passed in via uniform is the actual geometry that gets used to draw
+  // it. This is why this centered rect is used and not the original quad_rect.
+  gfx::RectF tile_rect = quad->visible_rect;
   GLC(gl_, gl_->UniformMatrix3fv(yuv_matrix_location, 1, 0, yuv_to_rgb));
   GLC(gl_, gl_->Uniform3fv(yuv_adj_location, 1, yuv_adjust));
 
   SetShaderOpacity(quad->opacity(), alpha_location);
-  DrawQuadGeometry(frame, quad->quadTransform(), quad->rect, matrix_location);
+  if (!clip_region) {
+    DrawQuadGeometry(frame, quad->quadTransform(), tile_rect, matrix_location);
+  } else {
+    gfx::QuadF region_quad = *clip_region;
+    region_quad.Scale(1.0f / tile_rect.width(), 1.0f / tile_rect.height());
+    region_quad -= gfx::Vector2dF(0.5f, 0.5f);
+    DrawQuadGeometryClippedByQuadF(frame, quad->quadTransform(), tile_rect,
+                                   region_quad, matrix_location);
+  }
 }
 
 void GLRenderer::DrawStreamVideoQuad(const DrawingFrame* frame,
-                                     const StreamVideoDrawQuad* quad) {
+                                     const StreamVideoDrawQuad* quad,
+                                     const gfx::QuadF* clip_region) {
   SetBlendEnabled(quad->ShouldDrawWithBlending());
 
   static float gl_matrix[16];
 
   DCHECK(capabilities_.using_egl_image);
 
   TexCoordPrecision tex_coord_precision = TexCoordPrecisionRequired(
       gl_,
       &highp_threshold_cache_,
       highp_threshold_min_,
@@ skipping 10 matching lines @@
 
   ResourceProvider::ScopedReadLockGL lock(resource_provider_,
                                           quad->resource_id);
   DCHECK_EQ(GL_TEXTURE0, GetActiveTextureUnit(gl_));
   GLC(gl_, gl_->BindTexture(GL_TEXTURE_EXTERNAL_OES, lock.texture_id()));
 
   GLC(gl_, gl_->Uniform1i(program->fragment_shader().sampler_location(), 0));
 
   SetShaderOpacity(quad->opacity(),
                    program->fragment_shader().alpha_location());
-  DrawQuadGeometry(frame,
-                   quad->quadTransform(),
-                   quad->rect,
-                   program->vertex_shader().matrix_location());
+  if (!clip_region) {
+    DrawQuadGeometry(frame, quad->quadTransform(), quad->rect,
+                     program->vertex_shader().matrix_location());
+  } else {
+    gfx::QuadF region_quad(*clip_region);
+    region_quad.Scale(1.0f / quad->rect.width(), 1.0f / quad->rect.height());
+    region_quad -= gfx::Vector2dF(0.5f, 0.5f);
+    DrawQuadGeometryClippedByQuadF(frame, quad->quadTransform(), quad->rect,
+                                   region_quad,
+                                   program->vertex_shader().matrix_location());
+  }
 }
 
 void GLRenderer::DrawPictureQuad(const DrawingFrame* frame,
-                                 const PictureDrawQuad* quad) {
+                                 const PictureDrawQuad* quad,
+                                 const gfx::QuadF* clip_region) {
   if (on_demand_tile_raster_bitmap_.width() != quad->texture_size.width() ||
       on_demand_tile_raster_bitmap_.height() != quad->texture_size.height()) {
     on_demand_tile_raster_bitmap_.allocN32Pixels(quad->texture_size.width(),
                                                  quad->texture_size.height());
 
     if (on_demand_tile_raster_resource_id_)
       resource_provider_->DeleteResource(on_demand_tile_raster_resource_id_);
 
     on_demand_tile_raster_resource_id_ = resource_provider_->CreateGLTexture(
         quad->texture_size,
@@ skipping 23 matching lines @@
     bitmap_pixels =
         reinterpret_cast<uint8_t*>(on_demand_tile_raster_bitmap_.getPixels());
   }
 
   resource_provider_->SetPixels(on_demand_tile_raster_resource_id_,
                                 bitmap_pixels,
                                 gfx::Rect(quad->texture_size),
                                 gfx::Rect(quad->texture_size),
                                 gfx::Vector2d());
 
-  DrawContentQuad(frame, quad, on_demand_tile_raster_resource_id_);
+  DrawContentQuad(frame, quad, on_demand_tile_raster_resource_id_, clip_region);
 }
 
 struct TextureProgramBinding {
   template <class Program>
   void Set(Program* program) {
     DCHECK(program);
     program_id = program->program();
     sampler_location = program->fragment_shader().sampler_location();
     matrix_location = program->vertex_shader().matrix_location();
     background_color_location =
         program->fragment_shader().background_color_location();
   }
   int program_id;
   int sampler_location;
   int matrix_location;
+  int transform_location;
   int background_color_location;
 };
 
 struct TexTransformTextureProgramBinding : TextureProgramBinding {
   template <class Program>
   void Set(Program* program) {
     TextureProgramBinding::Set(program);
     tex_transform_location = program->vertex_shader().tex_transform_location();
     vertex_opacity_location =
         program->vertex_shader().vertex_opacity_location();
   }
   int tex_transform_location;
   int vertex_opacity_location;
 };
 
-void GLRenderer::FlushTextureQuadCache() {
+void GLRenderer::FlushTextureQuadCache(bool using_clip_region) {
   // Check to see if we have anything to draw.
   if (draw_cache_.program_id == -1)
     return;
 
+  PrepareGeometry(using_clip_region ? ClippedBinding : SharedBinding);
+
   // Set the correct blending mode.
   SetBlendEnabled(draw_cache_.needs_blending);
 
   // Bind the program to the GL state.
   SetUseProgram(draw_cache_.program_id);
 
   // Bind the correct texture sampler location.
   GLC(gl_, gl_->Uniform1i(draw_cache_.sampler_location, 0));
 
   // Assume the current active textures is 0.
@@ skipping 40 matching lines @@
       gl_->DrawElements(GL_TRIANGLES,
                         6 * draw_cache_.matrix_data.size(),
                         GL_UNSIGNED_SHORT,
                         0));
 
   // Clear the cache.
   draw_cache_.program_id = -1;
   draw_cache_.uv_xform_data.resize(0);
   draw_cache_.vertex_opacity_data.resize(0);
   draw_cache_.matrix_data.resize(0);
+
+  if (using_clip_region) {
+    PrepareGeometry(SharedBinding);
+  }
 }
 
 void GLRenderer::EnqueueTextureQuad(const DrawingFrame* frame,
-                                    const TextureDrawQuad* quad) {
+                                    const TextureDrawQuad* quad,
+                                    const gfx::QuadF* clip_region) {
+  // If we have a clip_region then we have to render the next quad
+  // with dynamic geometry, therefore we must flush all pending
+  // texture quads.
+  if (clip_region) {
+    // We send in false here because we want to flush what's currently in the
+    // queue using the shared_geometry and not clipped_geometry
+    FlushTextureQuadCache(false);
+  }
+
   TexCoordPrecision tex_coord_precision = TexCoordPrecisionRequired(
       gl_,
       &highp_threshold_cache_,
       highp_threshold_min_,
       quad->shared_quad_state->visible_content_rect.bottom_right());
 
   // Choose the correct texture program binding
   TexTransformTextureProgramBinding binding;
   if (quad->premultiplied_alpha) {
     if (quad->background_color == SK_ColorTRANSPARENT) {
@@ skipping 11 matching lines @@
   }
 
   int resource_id = quad->resource_id;
 
   if (draw_cache_.program_id != binding.program_id ||
       draw_cache_.resource_id != resource_id ||
       draw_cache_.needs_blending != quad->ShouldDrawWithBlending() ||
       draw_cache_.nearest_neighbor != quad->nearest_neighbor ||
       draw_cache_.background_color != quad->background_color ||
       draw_cache_.matrix_data.size() >= 8) {
-    FlushTextureQuadCache();
+    FlushTextureQuadCache(false);
     draw_cache_.program_id = binding.program_id;
     draw_cache_.resource_id = resource_id;
     draw_cache_.needs_blending = quad->ShouldDrawWithBlending();
     draw_cache_.nearest_neighbor = quad->nearest_neighbor;
     draw_cache_.background_color = quad->background_color;
 
     draw_cache_.uv_xform_location = binding.tex_transform_location;
     draw_cache_.background_color_location = binding.background_color_location;
     draw_cache_.vertex_opacity_location = binding.vertex_opacity_location;
     draw_cache_.matrix_location = binding.matrix_location;
     draw_cache_.sampler_location = binding.sampler_location;
   }
 
   // Generate the uv-transform
-  draw_cache_.uv_xform_data.push_back(UVTransform(quad));
+  if (!clip_region) {
+    draw_cache_.uv_xform_data.push_back(UVTransform(quad));
+  } else {
+    Float4 uv_transform = {{0.0f, 0.0f, 1.0f, 1.0f}};
+    draw_cache_.uv_xform_data.push_back(uv_transform);
+  }
 
   // Generate the vertex opacity
   const float opacity = quad->opacity();
   draw_cache_.vertex_opacity_data.push_back(quad->vertex_opacity[0] * opacity);
   draw_cache_.vertex_opacity_data.push_back(quad->vertex_opacity[1] * opacity);
   draw_cache_.vertex_opacity_data.push_back(quad->vertex_opacity[2] * opacity);
   draw_cache_.vertex_opacity_data.push_back(quad->vertex_opacity[3] * opacity);
 
   // Generate the transform matrix
   gfx::Transform quad_rect_matrix;
   QuadRectTransform(&quad_rect_matrix, quad->quadTransform(), quad->rect);
   quad_rect_matrix = frame->projection_matrix * quad_rect_matrix;
 
   Float16 m;
   quad_rect_matrix.matrix().asColMajorf(m.data);
   draw_cache_.matrix_data.push_back(m);
+
+  if (clip_region) {
+    gfx::QuadF scaled_region;
+    if (!GetScaledRegion(quad->rect, clip_region, &scaled_region)) {
+      scaled_region = SharedGeometryQuad().BoundingBox();
+    }
+
+    float uv[8];
+    uv[0] = scaled_region.p1().x() + 0.5f;
+    uv[1] = scaled_region.p1().y() + 0.5f;
+    uv[2] = scaled_region.p2().x() + 0.5f;
+    uv[3] = scaled_region.p2().y() + 0.5f;
+    uv[4] = scaled_region.p3().x() + 0.5f;
+    uv[5] = scaled_region.p3().y() + 0.5f;
+    uv[6] = scaled_region.p4().x() + 0.5f;
+    uv[7] = scaled_region.p4().y() + 0.5f;
+    PrepareGeometry(ClippedBinding);
+    clipped_geometry_->InitializeCustomQuadWithUVs(scaled_region, uv);
+    FlushTextureQuadCache(true);
+  }
 }
 
 void GLRenderer::DrawIOSurfaceQuad(const DrawingFrame* frame,
-                                   const IOSurfaceDrawQuad* quad) {
+                                   const IOSurfaceDrawQuad* quad,
+                                   const gfx::QuadF* clip_region) {
   SetBlendEnabled(quad->ShouldDrawWithBlending());
 
   TexCoordPrecision tex_coord_precision = TexCoordPrecisionRequired(
       gl_,
       &highp_threshold_cache_,
       highp_threshold_min_,
       quad->shared_quad_state->visible_content_rect.bottom_right());
 
   TexTransformTextureProgramBinding binding;
   binding.Set(GetTextureIOSurfaceProgram(tex_coord_precision));
@@ skipping 18 matching lines @@
 
   const float vertex_opacity[] = {quad->opacity(), quad->opacity(),
                                   quad->opacity(), quad->opacity()};
   GLC(gl_, gl_->Uniform1fv(binding.vertex_opacity_location, 4, vertex_opacity));
 
   ResourceProvider::ScopedReadLockGL lock(resource_provider_,
                                           quad->io_surface_resource_id);
   DCHECK_EQ(GL_TEXTURE0, GetActiveTextureUnit(gl_));
   GLC(gl_, gl_->BindTexture(GL_TEXTURE_RECTANGLE_ARB, lock.texture_id()));
 
-  DrawQuadGeometry(
-      frame, quad->quadTransform(), quad->rect, binding.matrix_location);
+  if (!clip_region) {
+    DrawQuadGeometry(frame, quad->quadTransform(), quad->rect,
+                     binding.matrix_location);
+  } else {
+    DrawQuadGeometryClippedByQuadF(frame, quad->quadTransform(), quad->rect,
+                                   *clip_region, binding.matrix_location);
+  }
 
   GLC(gl_, gl_->BindTexture(GL_TEXTURE_RECTANGLE_ARB, 0));
 }
 
 void GLRenderer::FinishDrawingFrame(DrawingFrame* frame) {
   if (use_sync_query_) {
     DCHECK(current_sync_query_);
     current_sync_query_->End();
     pending_sync_queries_.push_back(current_sync_query_.Pass());
   }
 
   current_framebuffer_lock_ = nullptr;
   swap_buffer_rect_.Union(gfx::ToEnclosingRect(frame->root_damage_rect));
 
   GLC(gl_, gl_->Disable(GL_BLEND));
   blend_shadow_ = false;
 
   ScheduleOverlays(frame);
 }
 
-void GLRenderer::FinishDrawingQuadList() { FlushTextureQuadCache(); }
+void GLRenderer::FinishDrawingQuadList() {
+  FlushTextureQuadCache(false);
+}
 
 bool GLRenderer::FlippedFramebuffer(const DrawingFrame* frame) const {
   if (frame->current_render_pass != frame->root_render_pass)
     return true;
   return FlippedRootFramebuffer();
 }
 
 bool GLRenderer::FlippedRootFramebuffer() const {
   // GL is normally flipped, so a flipped output results in an unflipping.
   return !output_surface_->capabilities().flipped_output_surface;
 }
 
 void GLRenderer::EnsureScissorTestEnabled() {
   if (is_scissor_enabled_)
     return;
 
-  FlushTextureQuadCache();
+  FlushTextureQuadCache(false);
   GLC(gl_, gl_->Enable(GL_SCISSOR_TEST));
   is_scissor_enabled_ = true;
 }
 
 void GLRenderer::EnsureScissorTestDisabled() {
   if (!is_scissor_enabled_)
     return;
 
-  FlushTextureQuadCache();
+  FlushTextureQuadCache(false);
   GLC(gl_, gl_->Disable(GL_SCISSOR_TEST));
   is_scissor_enabled_ = false;
 }
 
 void GLRenderer::CopyCurrentRenderPassToBitmap(
     DrawingFrame* frame,
     scoped_ptr<CopyOutputRequest> request) {
   TRACE_EVENT0("cc", "GLRenderer::CopyCurrentRenderPassToBitmap");
   gfx::Rect copy_rect = frame->current_render_pass->output_rect;
   if (request->has_area())
@@ skipping 48 matching lines @@
   blend_shadow_ = enabled;
 }
 
 void GLRenderer::SetUseProgram(unsigned program) {
   if (program == program_shadow_)
     return;
   gl_->UseProgram(program);
   program_shadow_ = program;
 }
 
+void GLRenderer::DrawQuadGeometryClippedByQuadF(
+    const DrawingFrame* frame,
+    const gfx::Transform& draw_transform,
+    const gfx::RectF& quad_rect,
+    const gfx::QuadF& clipping_region_quad,
+    int matrix_location,
+    const float* uvs) {
+  PrepareGeometry(ClippedBinding);
+  if (uvs) {
+    clipped_geometry_->InitializeCustomQuadWithUVs(clipping_region_quad, uvs);
+  } else {
+    clipped_geometry_->InitializeCustomQuad(clipping_region_quad);
+  }
+  gfx::Transform quad_rect_matrix;
+  QuadRectTransform(&quad_rect_matrix, draw_transform, quad_rect);
+  static float gl_matrix[16];
+  ToGLMatrix(&gl_matrix[0], frame->projection_matrix * quad_rect_matrix);
+  GLC(gl_, gl_->UniformMatrix4fv(matrix_location, 1, false, &gl_matrix[0]));
+
+  GLC(gl_, gl_->DrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT,
+                             reinterpret_cast<const void*>(0)));
+}
+
 void GLRenderer::DrawQuadGeometry(const DrawingFrame* frame,
                                   const gfx::Transform& draw_transform,
                                   const gfx::RectF& quad_rect,
                                   int matrix_location) {
+  PrepareGeometry(SharedBinding);
   gfx::Transform quad_rect_matrix;
   QuadRectTransform(&quad_rect_matrix, draw_transform, quad_rect);
   static float gl_matrix[16];
   ToGLMatrix(&gl_matrix[0], frame->projection_matrix * quad_rect_matrix);
   GLC(gl_, gl_->UniformMatrix4fv(matrix_location, 1, false, &gl_matrix[0]));
 
   GLC(gl_, gl_->DrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, 0));
 }
 
 void GLRenderer::Finish() {
@@ skipping 68 matching lines @@
     return;
 
   output_surface_->EnsureBackbuffer();
   is_backbuffer_discarded_ = false;
 }
 
 void GLRenderer::GetFramebufferPixelsAsync(
     const DrawingFrame* frame,
     const gfx::Rect& rect,
     scoped_ptr<CopyOutputRequest> request) {
+  PrepareGeometry(NoBinding);

[enne (OOO), 2015/02/04 21:24:00]

Why does this need to happen? Does NoBinding need to exist?

[awoloszyn, 2015/02/12 16:48:51]

Once we have called GetFramebufferPixelsAsync, we have to rebind the geometry.
Currently if SharedBinding is active, and we call
PrepareGeometry(SharedBinding), nothing happens, but this will force it to get
rebound. That being said, it may make sense to move this to EnforceMemoryPolicy.

   DCHECK(!request->IsEmpty());
   if (request->IsEmpty())
     return;
   if (rect.IsEmpty())
     return;
 
   gfx::Rect window_rect = MoveFromDrawToWindowSpace(frame, rect);
   DCHECK_GE(window_rect.x(), 0);
   DCHECK_GE(window_rect.y(), 0);
   DCHECK_LE(window_rect.right(), current_surface_size_.width());
@@ skipping 283 matching lines @@
 
 void GLRenderer::SetScissorTestRect(const gfx::Rect& scissor_rect) {
   EnsureScissorTestEnabled();
 
   // Don't unnecessarily ask the context to change the scissor, because it
   // may cause undesired GPU pipeline flushes.
   if (scissor_rect == scissor_rect_ && !scissor_rect_needs_reset_)
     return;
 
   scissor_rect_ = scissor_rect;
-  FlushTextureQuadCache();
+  FlushTextureQuadCache(false);
   GLC(gl_,
       gl_->Scissor(scissor_rect.x(),
                    scissor_rect.y(),
                    scissor_rect.width(),
                    scissor_rect.height()));
 
   scissor_rect_needs_reset_ = false;
 }
 
 void GLRenderer::SetDrawViewport(const gfx::Rect& window_space_viewport) {
   viewport_ = window_space_viewport;
   GLC(gl_,
       gl_->Viewport(window_space_viewport.x(),
                     window_space_viewport.y(),
                     window_space_viewport.width(),
                     window_space_viewport.height()));
 }
 
 void GLRenderer::InitializeSharedObjects() {
   TRACE_EVENT0("cc", "GLRenderer::InitializeSharedObjects");
 
   // Create an FBO for doing offscreen rendering.
   GLC(gl_, gl_->GenFramebuffers(1, &offscreen_framebuffer_id_));
 
-  shared_geometry_ = make_scoped_ptr(
-      new GeometryBinding(gl_, QuadVertexRect()));
+  shared_geometry_ =
+      make_scoped_ptr(new StaticGeometryBinding(gl_, QuadVertexRect()));
+  clipped_geometry_ = make_scoped_ptr(new DynamicGeometryBinding(gl_));
+}
+
+void GLRenderer::PrepareGeometry(BoundGeometry binding) {
+  if (binding == bound_geometry_) {
+    return;
+  }
+
+  switch (binding) {
+    case SharedBinding:
+      shared_geometry_->PrepareForDraw();
+      break;
+    case ClippedBinding:
+      clipped_geometry_->PrepareForDraw();
+      break;
+    case NoBinding:
+      break;
+  }
+  bound_geometry_ = binding;
 }
 
 const GLRenderer::TileCheckerboardProgram*
 GLRenderer::GetTileCheckerboardProgram() {
   if (!tile_checkerboard_program_.initialized()) {
     TRACE_EVENT0("cc", "GLRenderer::checkerboardProgram::initalize");
     tile_checkerboard_program_.Initialize(output_surface_->context_provider(),
                                           TexCoordPrecisionNA,
                                           SamplerTypeNA);
   }
@@ skipping 455 matching lines @@
   scissor_rect_needs_reset_ = true;
   stencil_shadow_ = false;
   blend_shadow_ = true;
   program_shadow_ = 0;
 
   RestoreGLState();
 }
 
 void GLRenderer::RestoreGLState() {
   // This restores the current GLRenderer state to the GL context.
-
-  shared_geometry_->PrepareForDraw();
+  bound_geometry_ = NoBinding;
+  PrepareGeometry(SharedBinding);
 
   GLC(gl_, gl_->Disable(GL_DEPTH_TEST));
   GLC(gl_, gl_->Disable(GL_CULL_FACE));
   GLC(gl_, gl_->ColorMask(true, true, true, true));
   GLC(gl_, gl_->BlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA));
   GLC(gl_, gl_->ActiveTexture(GL_TEXTURE0));
 
   if (program_shadow_)
     gl_->UseProgram(program_shadow_);
 
@@ skipping 47 matching lines @@
     context_support_->ScheduleOverlayPlane(
         overlay.plane_z_order,
         overlay.transform,
         pending_overlay_resources_.back()->texture_id(),
         overlay.display_rect,
         overlay.uv_rect);
   }
 }
 
 }  // namespace cc