xref: /aosp_15_r20/external/skia/modules/sksg/src/SkSGMerge.cpp (revision c8dee2aa9b3f27cf6c858bd81872bdeb2c07ed17)
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 "modules/sksg/include/SkSGMerge.h"
9 
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkClipOp.h"
12 #include "include/core/SkPoint.h"
13 #include "include/pathops/SkPathOps.h"
14 #include "include/private/base/SkAssert.h"
15 #include "modules/sksg/include/SkSGNode.h"
16 #include "src/core/SkPathPriv.h"
17 
18 class SkMatrix;
19 
20 namespace sksg {
21 
Merge(std::vector<Rec> && recs)22 Merge::Merge(std::vector<Rec>&& recs)
23     : fRecs(std::move(recs)) {
24     for (const auto& rec : fRecs) {
25         this->observeInval(rec.fGeo);
26     }
27 }
28 
~Merge()29 Merge::~Merge() {
30     for (const auto& rec : fRecs) {
31         this->unobserveInval(rec.fGeo);
32     }
33 }
34 
onClip(SkCanvas * canvas,bool antiAlias) const35 void Merge::onClip(SkCanvas* canvas, bool antiAlias) const {
36     canvas->clipPath(fMerged, SkClipOp::kIntersect, antiAlias);
37 }
38 
onDraw(SkCanvas * canvas,const SkPaint & paint) const39 void Merge::onDraw(SkCanvas* canvas, const SkPaint& paint) const {
40     canvas->drawPath(fMerged, paint);
41 }
42 
onContains(const SkPoint & p) const43 bool Merge::onContains(const SkPoint& p) const {
44     return fMerged.contains(p.x(), p.y());
45 }
46 
onAsPath() const47 SkPath Merge::onAsPath() const {
48     return fMerged;
49 }
50 
mode_to_op(Merge::Mode mode)51 static SkPathOp mode_to_op(Merge::Mode mode) {
52     switch (mode) {
53     case Merge::Mode::kUnion:
54         return kUnion_SkPathOp;
55     case Merge::Mode::kIntersect:
56         return kIntersect_SkPathOp;
57     case Merge::Mode::kDifference:
58         return kDifference_SkPathOp;
59     case Merge::Mode::kReverseDifference:
60         return kReverseDifference_SkPathOp;
61     case Merge::Mode::kXOR:
62         return kXOR_SkPathOp;
63     default:
64         break;
65     }
66 
67     return kUnion_SkPathOp;
68 }
69 
onRevalidate(InvalidationController * ic,const SkMatrix & ctm)70 SkRect Merge::onRevalidate(InvalidationController* ic, const SkMatrix& ctm) {
71     SkASSERT(this->hasInval());
72 
73     SkOpBuilder builder;
74 
75     fMerged.reset();
76     bool in_builder = false;
77 
78     auto append = [&](const SkPath& path) {
79         if (in_builder) {
80             builder.resolve(&fMerged);
81             in_builder = false;
82         }
83 
84         if (fMerged.isEmpty()) {
85             // First merge path determines the fill type.
86             fMerged = path;
87         } else {
88             fMerged.addPath(path);
89         }
90     };
91 
92     for (const auto& rec : fRecs) {
93         rec.fGeo->revalidate(ic, ctm);
94 
95         if (rec.fMode == Mode::kMerge) {
96             // Merge (append) is not supported by SkOpBuidler.
97             append(rec.fGeo->asPath());
98             continue;
99         }
100 
101         if (!in_builder) {
102             builder.add(fMerged, kUnion_SkPathOp);
103             in_builder = true;
104         }
105 
106         builder.add(rec.fGeo->asPath(), mode_to_op(rec.fMode));
107     }
108 
109     if (in_builder) {
110         builder.resolve(&fMerged);
111     }
112 
113     SkPathPriv::ShrinkToFit(&fMerged);
114 
115     return fMerged.computeTightBounds();
116 }
117 
118 } // namespace sksg
119