xref: /aosp_15_r20/external/skia/modules/sksg/src/SkSGOpacityEffect.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
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 "include/private/base/SkAssert.h"
9 #include "modules/sksg/include/SkSGOpacityEffect.h"
10 
11 class SkCanvas;
12 class SkMatrix;
13 struct SkPoint;
14 
15 namespace sksg {
16 class InvalidationController;
17 
OpacityEffect(sk_sp<RenderNode> child,float opacity)18 OpacityEffect::OpacityEffect(sk_sp<RenderNode> child, float opacity)
19     : INHERITED(std::move(child))
20     , fOpacity(opacity) {}
21 
onRender(SkCanvas * canvas,const RenderContext * ctx) const22 void OpacityEffect::onRender(SkCanvas* canvas, const RenderContext* ctx) const {
23     // opacity <= 0 disables rendering
24     if (fOpacity <= 0)
25         return;
26 
27     // opacity >= 1 has no effect
28     if (fOpacity >= 1) {
29         this->INHERITED::onRender(canvas, ctx);
30         return;
31     }
32 
33     const auto local_context = ScopedRenderContext(canvas, ctx).modulateOpacity(fOpacity);
34 
35     this->INHERITED::onRender(canvas, local_context);
36 }
37 
onNodeAt(const SkPoint & p) const38 const RenderNode* OpacityEffect::onNodeAt(const SkPoint& p) const {
39     return (fOpacity > 0) ? this->INHERITED::onNodeAt(p) : nullptr;
40 }
41 
onRevalidate(InvalidationController * ic,const SkMatrix & ctm)42 SkRect OpacityEffect::onRevalidate(InvalidationController* ic, const SkMatrix& ctm) {
43     SkASSERT(this->hasInval());
44 
45     // opacity <= 0 disables rendering AND revalidation for the sub-DAG
46     return fOpacity > 0 ? this->INHERITED::onRevalidate(ic, ctm) : SkRect::MakeEmpty();
47 }
48 
49 } // namespace sksg
50