| // 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/trees/occlusion.h" |
| |
| #include "cc/base/math_util.h" |
| #include "ui/gfx/rect.h" |
| |
| namespace cc { |
| |
| Occlusion::Occlusion() { |
| } |
| |
| Occlusion::Occlusion(const gfx::Transform& draw_transform, |
| const SimpleEnclosedRegion& occlusion_from_outside_target, |
| const SimpleEnclosedRegion& occlusion_from_inside_target) |
| : draw_transform_(draw_transform), |
| occlusion_from_outside_target_(occlusion_from_outside_target), |
| occlusion_from_inside_target_(occlusion_from_inside_target) { |
| } |
| |
| bool Occlusion::IsOccluded(const gfx::Rect& content_rect) const { |
| if (content_rect.IsEmpty()) |
| return true; |
| |
| if (occlusion_from_inside_target_.IsEmpty() && |
| occlusion_from_outside_target_.IsEmpty()) { |
| return false; |
| } |
| |
| // Take the ToEnclosingRect at each step, as we want to contain any unoccluded |
| // partial pixels in the resulting Rect. |
| gfx::Rect unoccluded_rect_in_target_surface = |
| MathUtil::MapEnclosingClippedRect(draw_transform_, content_rect); |
| DCHECK_LE(occlusion_from_inside_target_.GetRegionComplexity(), 1u); |
| DCHECK_LE(occlusion_from_outside_target_.GetRegionComplexity(), 1u); |
| // These subtract operations are more lossy than if we did both operations at |
| // once. |
| unoccluded_rect_in_target_surface.Subtract( |
| occlusion_from_inside_target_.bounds()); |
| unoccluded_rect_in_target_surface.Subtract( |
| occlusion_from_outside_target_.bounds()); |
| |
| return unoccluded_rect_in_target_surface.IsEmpty(); |
| } |
| |
| } // namespace cc |