Refactor OverlayStrategySandwich and OverlayStrategyCommon

cc/output/overlay_strategy_common.cc

-// Copyright 2015 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_common.h"
-
-#include "cc/quads/solid_color_draw_quad.h"
-
-namespace cc {
-
-OverlayStrategyCommon::OverlayStrategyCommon(
-    OverlayCandidateValidator* capability_checker,
-    OverlayStrategyCommonDelegate* delegate)
-    : capability_checker_(capability_checker), delegate_(delegate) {}
-
-OverlayStrategyCommon::~OverlayStrategyCommon() {
-}
-
-bool OverlayStrategyCommon::Attempt(RenderPassList* render_passes_in_draw_order,
-                                    OverlayCandidateList* candidate_list,
-                                    float device_scale_factor) {
-  if (!capability_checker_)
-    return false;
-  RenderPass* root_render_pass = render_passes_in_draw_order->back();
-  DCHECK(root_render_pass);
-
-  bool created_overlay = false;
-  QuadList& quad_list = root_render_pass->quad_list;
-  for (auto it = quad_list.begin(); it != quad_list.end();) {
-    OverlayCandidate candidate;
-    if (!OverlayCandidate::FromDrawQuad(*it, &candidate)) {
-      ++it;
-      continue;
-    }
-
-    OverlayResult result = delegate_->TryOverlay(
-        capability_checker_, render_passes_in_draw_order, candidate_list,
-        candidate, &it, device_scale_factor);
-    switch (result) {
-      case DID_NOT_CREATE_OVERLAY:
-        ++it;
-        break;
-      case CREATED_OVERLAY_STOP_LOOKING:
-        return true;
-      case CREATED_OVERLAY_KEEP_LOOKING:
-        created_overlay = true;
-        break;
-    }
-  }
-
-  return created_overlay;
-}
-
-// static
-bool OverlayStrategyCommon::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->shared_quad_state->opacity;
-    float alpha = (SkColorGetA(color) * (1.0f / 255.0f)) * opacity;
-    return solid_quad->ShouldDrawWithBlending() &&
-           alpha < std::numeric_limits<float>::epsilon();
-  }
-  return false;
-}
-
-}  // namespace cc