Revert "Delete CC."

cc/output/overlay_strategy_single_on_top.cc

Index: cc/output/overlay_strategy_single_on_top.cc
diff --git a/cc/output/overlay_strategy_single_on_top.cc b/cc/output/overlay_strategy_single_on_top.cc
new file mode 100644
index 0000000000000000000000000000000000000000..71897ed4596cc1f72bc370bba044136649ff0fe3
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+++ b/cc/output/overlay_strategy_single_on_top.cc
@@ -0,0 +1,196 @@
+// Copyright 2014 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/overlay_strategy_single_on_top.h"
+
+#include <limits>
+
+#include "cc/quads/draw_quad.h"
+#include "cc/quads/solid_color_draw_quad.h"
+#include "cc/quads/stream_video_draw_quad.h"
+#include "cc/quads/texture_draw_quad.h"
+#include "ui/gfx/geometry/point3_f.h"
+#include "ui/gfx/geometry/rect_conversions.h"
+#include "ui/gfx/transform.h"
+
+namespace cc {
+
+OverlayStrategySingleOnTop::OverlayStrategySingleOnTop(
+    OverlayCandidateValidator* capability_checker,
+    ResourceProvider* resource_provider)
+    : capability_checker_(capability_checker),
+      resource_provider_(resource_provider) {}
+
+bool OverlayStrategySingleOnTop::IsOverlayQuad(const DrawQuad* draw_quad) {
+  unsigned int resource_id;
+  switch (draw_quad->material) {
+    case DrawQuad::TEXTURE_CONTENT:
+      resource_id = TextureDrawQuad::MaterialCast(draw_quad)->resource_id;
+      break;
+    case DrawQuad::STREAM_VIDEO_CONTENT:
+      resource_id = StreamVideoDrawQuad::MaterialCast(draw_quad)->resource_id;
+      break;
+    default:
+      return false;
+  }
+  return resource_provider_->AllowOverlay(resource_id);
+}
+
+bool OverlayStrategySingleOnTop::GetTextureQuadInfo(
+    const TextureDrawQuad& quad,
+    OverlayCandidate* quad_info) {
+  gfx::OverlayTransform overlay_transform =
+      OverlayCandidate::GetOverlayTransform(quad.quadTransform(), quad.flipped);
+  if (quad.background_color != SK_ColorTRANSPARENT ||
+      quad.premultiplied_alpha ||
+      overlay_transform == gfx::OVERLAY_TRANSFORM_INVALID)
+    return false;
+  quad_info->resource_id = quad.resource_id;
+  quad_info->transform = overlay_transform;
+  quad_info->uv_rect = BoundingRect(quad.uv_top_left, quad.uv_bottom_right);
+  return true;
+}
+
+bool OverlayStrategySingleOnTop::GetVideoQuadInfo(
+    const StreamVideoDrawQuad& quad,
+    OverlayCandidate* quad_info) {
+  gfx::OverlayTransform overlay_transform =
+      OverlayCandidate::GetOverlayTransform(quad.quadTransform(), false);
+  if (overlay_transform == gfx::OVERLAY_TRANSFORM_INVALID)
+    return false;
+  if (!quad.matrix.IsScaleOrTranslation()) {
+    // We cannot handle anything other than scaling & translation for texture
+    // coordinates yet.
+    return false;
+  }
+  quad_info->resource_id = quad.resource_id;
+  quad_info->transform = overlay_transform;
+
+  gfx::Point3F uv0 = gfx::Point3F(0, 0, 0);
+  gfx::Point3F uv1 = gfx::Point3F(1, 1, 0);
+  quad.matrix.TransformPoint(&uv0);
+  quad.matrix.TransformPoint(&uv1);
+  gfx::Vector3dF delta = uv1 - uv0;
+  if (delta.x() < 0) {
+    quad_info->transform = OverlayCandidate::ModifyTransform(
+        quad_info->transform, gfx::OVERLAY_TRANSFORM_FLIP_HORIZONTAL);
+    float x0 = uv0.x();
+    uv0.set_x(uv1.x());
+    uv1.set_x(x0);
+    delta.set_x(-delta.x());
+  }
+
+  if (delta.y() < 0) {
+    // In this situation, uv0y < uv1y. Since we overlay inverted, a request
+    // to invert the source texture means we can just output the texture
+    // normally and it will be correct.
+    quad_info->uv_rect = gfx::RectF(uv0.x(), uv1.y(), delta.x(), -delta.y());
+  } else {
+    quad_info->transform = OverlayCandidate::ModifyTransform(
+        quad_info->transform, gfx::OVERLAY_TRANSFORM_FLIP_VERTICAL);
+    quad_info->uv_rect = gfx::RectF(uv0.x(), uv0.y(), delta.x(), delta.y());
+  }
+  return true;
+}
+
+bool OverlayStrategySingleOnTop::GetCandidateQuadInfo(
+    const DrawQuad& draw_quad,
+    OverlayCandidate* quad_info) {
+  // All quad checks.
+  if (draw_quad.needs_blending || draw_quad.shared_quad_state->opacity != 1.f ||
+      draw_quad.shared_quad_state->blend_mode != SkXfermode::kSrcOver_Mode)
+    return false;
+
+  if (draw_quad.material == DrawQuad::TEXTURE_CONTENT) {
+    const TextureDrawQuad& quad = *TextureDrawQuad::MaterialCast(&draw_quad);
+    if (!GetTextureQuadInfo(quad, quad_info))
+      return false;
+  } else if (draw_quad.material == DrawQuad::STREAM_VIDEO_CONTENT) {
+    const StreamVideoDrawQuad& quad =
+        *StreamVideoDrawQuad::MaterialCast(&draw_quad);
+    if (!GetVideoQuadInfo(quad, quad_info))
+      return false;
+  }
+
+  quad_info->format = RGBA_8888;
+  quad_info->display_rect = OverlayCandidate::GetOverlayRect(
+      draw_quad.quadTransform(), draw_quad.rect);
+  return true;
+}
+
+bool OverlayStrategySingleOnTop::IsInvisibleQuad(const DrawQuad* draw_quad) {
+  if (draw_quad->material == DrawQuad::SOLID_COLOR) {
+    const SolidColorDrawQuad* solid_quad =
+        SolidColorDrawQuad::MaterialCast(draw_quad);
+    SkColor color = solid_quad->color;
+    float opacity = solid_quad->opacity();
+    float alpha = (SkColorGetA(color) * (1.0f / 255.0f)) * opacity;
+    // Ignore transparent solid color quads.
+    return solid_quad->ShouldDrawWithBlending() &&
+           alpha < std::numeric_limits<float>::epsilon();
+  }
+  return false;
+}
+
+bool OverlayStrategySingleOnTop::Attempt(
+    RenderPassList* render_passes_in_draw_order,
+    OverlayCandidateList* candidate_list) {
+  // Only attempt to handle very simple case for now.
+  if (!capability_checker_)
+    return false;
+
+  RenderPass* root_render_pass = render_passes_in_draw_order->back();
+  DCHECK(root_render_pass);
+
+  OverlayCandidate candidate;
+  QuadList& quad_list = root_render_pass->quad_list;
+  auto candidate_iterator = quad_list.end();
+  for (auto it = quad_list.begin(); it != quad_list.end(); ++it) {
+    const DrawQuad* draw_quad = *it;
+    if (IsOverlayQuad(draw_quad)) {
+      // Check that no prior quads overlap it.
+      bool intersects = false;
+      gfx::RectF rect = draw_quad->rect;
+      draw_quad->quadTransform().TransformRect(&rect);
+      for (auto overlap_iter = quad_list.cbegin(); overlap_iter != it;
+           ++overlap_iter) {
+        gfx::RectF overlap_rect = overlap_iter->rect;
+        overlap_iter->quadTransform().TransformRect(&overlap_rect);
+        if (rect.Intersects(overlap_rect) && !IsInvisibleQuad(*overlap_iter)) {
+          intersects = true;
+          break;
+        }
+      }
+      if (intersects || !GetCandidateQuadInfo(*draw_quad, &candidate))
+        continue;
+      candidate_iterator = it;
+      break;
+    }
+  }
+  if (candidate_iterator == quad_list.end())
+    return false;
+
+  // Add our primary surface.
+  OverlayCandidateList candidates;
+  OverlayCandidate main_image;
+  main_image.display_rect = root_render_pass->output_rect;
+  candidates.push_back(main_image);
+
+  // Add the overlay.
+  candidate.plane_z_order = 1;
+  candidates.push_back(candidate);
+
+  // Check for support.
+  capability_checker_->CheckOverlaySupport(&candidates);
+
+  // If the candidate can be handled by an overlay, create a pass for it.
+  if (candidates[1].overlay_handled) {
+    quad_list.EraseAndInvalidateAllPointers(candidate_iterator);
+    candidate_list->swap(candidates);
+    return true;
+  }
+  return false;
+}
+
+}  // namespace cc