cc/output/overlay_strategy_underlay.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "cc/output/overlay_strategy_underlay.h"
   6
   7 #include "cc/output/overlay_candidate_validator.h"
   8 #include "cc/quads/draw_quad.h"
   9 #include "cc/quads/solid_color_draw_quad.h"
  10
  11 namespace cc {
  12
  13 OverlayStrategyUnderlay::OverlayStrategyUnderlay(
  14     OverlayCandidateValidator* capability_checker)
  15     : capability_checker_(capability_checker) {
  16 }
  17
  18 bool OverlayStrategyUnderlay::Attempt(
  19     RenderPassList* render_passes_in_draw_order,
  20     OverlayCandidateList* candidate_list) {
  21   if (!capability_checker_)
  22     return false;
  23
  24   RenderPass* root_render_pass = render_passes_in_draw_order->back();
  25   DCHECK(root_render_pass);
  26
  27   OverlayCandidate candidate;
  28   QuadList& quad_list = root_render_pass->quad_list;
  29   auto candidate_iterator = quad_list.end();
  30   for (auto it = quad_list.begin(); it != quad_list.end(); ++it) {
  31     if (IsOverlayQuad(*it) && GetCandidateQuadInfo(**it, &candidate)) {
  32       candidate_iterator = it;
  33       break;
  34     }
  35   }
  36   if (candidate_iterator == quad_list.end())
  37     return false;
  38
  39   // Add our primary surface.
  40   OverlayCandidateList candidates;
  41   OverlayCandidate main_image;
  42   main_image.display_rect = root_render_pass->output_rect;
  43   candidates.push_back(main_image);
  44
  45   // Add the overlay.
  46   candidate.plane_z_order = -1;
  47   candidates.push_back(candidate);
  48
  49   // Check for support.
  50   capability_checker_->CheckOverlaySupport(&candidates);
  51
  52   // If the candidate can be handled by an overlay, create a pass for it. We
  53   // need to switch out the video quad with a black transparent one.
  54   if (candidates[1].overlay_handled) {
  55     const SharedQuadState* shared_quad_state =
  56         candidate_iterator->shared_quad_state;
  57     gfx::Rect rect = candidate_iterator->visible_rect;
  58     SolidColorDrawQuad* replacement =
  59         quad_list.ReplaceExistingElement<SolidColorDrawQuad>(
  60             candidate_iterator);
  61     replacement->SetAll(shared_quad_state, rect, rect, rect, false,
  62                         SK_ColorTRANSPARENT, true);
  63     candidate_list->swap(candidates);
  64     return true;
  65   }
  66   return false;
  67 }
  68
  69 }  // namespace cc