1 /* 2 * Copyright 2018 Google Inc. 3 * 4 * Use of this source code is governed by a BSD-style license that can be 5 * found in the LICENSE file. 6 */ 7 8 #include "SkSGMaskEffect.h" 9 10 #include "SkCanvas.h" 11 12 namespace sksg { 13 14 MaskEffect::MaskEffect(sk_sp<RenderNode> child, sk_sp<RenderNode> mask, Mode mode) 15 : INHERITED(std::move(child)) 16 , fMaskNode(std::move(mask)) 17 , fMaskMode(mode) { 18 this->observeInval(fMaskNode); 19 } 20 21 MaskEffect::~MaskEffect() { 22 this->unobserveInval(fMaskNode); 23 } 24 25 void MaskEffect::onRender(SkCanvas* canvas, const RenderContext* ctx) const { 26 if (this->bounds().isEmpty()) 27 return; 28 29 SkAutoCanvasRestore acr(canvas, false); 30 31 canvas->saveLayer(this->bounds(), nullptr); 32 // Note: the paint overrides in ctx don't apply to the mask. 33 fMaskNode->render(canvas); 34 35 36 SkPaint p; 37 p.setBlendMode(fMaskMode == Mode::kNormal ? SkBlendMode::kSrcIn : SkBlendMode::kSrcOut); 38 canvas->saveLayer(this->bounds(), &p); 39 40 this->INHERITED::onRender(canvas, ctx); 41 } 42 43 44 SkRect MaskEffect::onRevalidate(InvalidationController* ic, const SkMatrix& ctm) { 45 SkASSERT(this->hasInval()); 46 47 const auto maskBounds = fMaskNode->revalidate(ic, ctm); 48 auto childBounds = this->INHERITED::onRevalidate(ic, ctm); 49 50 return (fMaskMode == Mode::kInvert || childBounds.intersect(maskBounds)) 51 ? childBounds 52 : SkRect::MakeEmpty(); 53 } 54 55 } // namespace sksg 56
