| // Copyright 2013 The Flutter 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 "flutter/flow/layers/backdrop_filter_layer.h" |
| |
| namespace flutter { |
| |
| BackdropFilterLayer::BackdropFilterLayer( |
| std::shared_ptr<const DlImageFilter> filter, |
| DlBlendMode blend_mode) |
| : filter_(std::move(filter)), blend_mode_(blend_mode) {} |
| |
| void BackdropFilterLayer::Diff(DiffContext* context, const Layer* old_layer) { |
| DiffContext::AutoSubtreeRestore subtree(context); |
| auto* prev = static_cast<const BackdropFilterLayer*>(old_layer); |
| if (!context->IsSubtreeDirty()) { |
| FML_DCHECK(prev); |
| if (NotEquals(filter_, prev->filter_)) { |
| context->MarkSubtreeDirty(context->GetOldLayerPaintRegion(old_layer)); |
| } |
| } |
| |
| // Backdrop filter paints everywhere in cull rect |
| auto paint_bounds = context->GetCullRect(); |
| context->AddLayerBounds(paint_bounds); |
| |
| if (filter_) { |
| paint_bounds = context->MapRect(paint_bounds); |
| auto filter_target_bounds = paint_bounds.roundOut(); |
| SkIRect filter_input_bounds; // in screen coordinates |
| filter_->get_input_device_bounds( |
| filter_target_bounds, context->GetTransform3x3(), filter_input_bounds); |
| context->AddReadbackRegion(filter_input_bounds); |
| } |
| |
| DiffChildren(context, prev); |
| |
| context->SetLayerPaintRegion(this, context->CurrentSubtreeRegion()); |
| } |
| |
| void BackdropFilterLayer::Preroll(PrerollContext* context) { |
| Layer::AutoPrerollSaveLayerState save = |
| Layer::AutoPrerollSaveLayerState::Create(context, true, bool(filter_)); |
| if (context->view_embedder != nullptr) { |
| context->view_embedder->PushFilterToVisitedPlatformViews( |
| filter_, context->state_stack.device_cull_rect()); |
| } |
| SkRect child_paint_bounds = SkRect::MakeEmpty(); |
| PrerollChildren(context, &child_paint_bounds); |
| child_paint_bounds.join(context->state_stack.local_cull_rect()); |
| set_paint_bounds(child_paint_bounds); |
| context->renderable_state_flags = kSaveLayerRenderFlags; |
| } |
| |
| void BackdropFilterLayer::Paint(PaintContext& context) const { |
| FML_DCHECK(needs_painting(context)); |
| |
| auto mutator = context.state_stack.save(); |
| mutator.applyBackdropFilter(paint_bounds(), filter_, blend_mode_); |
| |
| PaintChildren(context); |
| } |
| |
| } // namespace flutter |