1 /*
2  * Copyright 2017 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 "SkSGTrimEffect.h"
9 
10 #include "SkCanvas.h"
11 #include "SkStrokeRec.h"
12 #include "SkTrimPathEffect.h"
13 
14 namespace sksg {
15 
TrimEffect(sk_sp<GeometryNode> child)16 TrimEffect::TrimEffect(sk_sp<GeometryNode> child)
17     : fChild(std::move(child)) {
18     this->observeInval(fChild);
19 }
20 
~TrimEffect()21 TrimEffect::~TrimEffect() {
22     this->unobserveInval(fChild);
23 }
24 
onClip(SkCanvas * canvas,bool antiAlias) const25 void TrimEffect::onClip(SkCanvas* canvas, bool antiAlias) const {
26     canvas->clipPath(fTrimmedPath, SkClipOp::kIntersect, antiAlias);
27 }
28 
onDraw(SkCanvas * canvas,const SkPaint & paint) const29 void TrimEffect::onDraw(SkCanvas* canvas, const SkPaint& paint) const {
30     SkASSERT(!paint.getPathEffect());
31 
32     canvas->drawPath(fTrimmedPath, paint);
33 }
34 
onAsPath() const35 SkPath TrimEffect::onAsPath() const {
36     return fTrimmedPath;
37 }
38 
onRevalidate(InvalidationController * ic,const SkMatrix & ctm)39 SkRect TrimEffect::onRevalidate(InvalidationController* ic, const SkMatrix& ctm) {
40     SkASSERT(this->hasInval());
41 
42     const auto childbounds = fChild->revalidate(ic, ctm);
43     const auto path        = fChild->asPath();
44 
45     if (auto trim = SkTrimPathEffect::Make(fStart, fStop, fMode)) {
46         fTrimmedPath.reset();
47         SkStrokeRec rec(SkStrokeRec::kHairline_InitStyle);
48         SkAssertResult(trim->filterPath(&fTrimmedPath, path, &rec, &childbounds));
49     } else {
50         fTrimmedPath = path;
51     }
52 
53     fTrimmedPath.shrinkToFit();
54 
55     return fTrimmedPath.computeTightBounds();
56 }
57 
58 } // namespace sksg
59