1 /*
2 * Copyright 2020 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/SkSGGeometryEffect.h"
9
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkClipOp.h"
12 #include "include/core/SkMatrix.h"
13 #include "include/core/SkPath.h"
14 #include "include/core/SkPathEffect.h"
15 #include "include/core/SkPathUtils.h"
16 #include "include/core/SkPoint.h"
17 #include "include/core/SkStrokeRec.h"
18 #include "include/effects/SkCornerPathEffect.h"
19 #include "include/effects/SkDashPathEffect.h"
20 #include "include/effects/SkTrimPathEffect.h"
21 #include "include/pathops/SkPathOps.h"
22 #include "include/private/base/SkAssert.h"
23 #include "include/private/base/SkTArray.h"
24 #include "include/private/base/SkTo.h"
25 #include "modules/sksg/src/SkSGTransformPriv.h"
26 #include "src/core/SkPathPriv.h"
27
28 #include <algorithm>
29 #include <cmath>
30
31 using namespace skia_private;
32
33 namespace sksg {
34
GeometryEffect(sk_sp<GeometryNode> child)35 GeometryEffect::GeometryEffect(sk_sp<GeometryNode> child)
36 : fChild(std::move(child)) {
37 SkASSERT(fChild);
38
39 this->observeInval(fChild);
40 }
41
~GeometryEffect()42 GeometryEffect::~GeometryEffect() {
43 this->unobserveInval(fChild);
44 }
45
onClip(SkCanvas * canvas,bool antiAlias) const46 void GeometryEffect::onClip(SkCanvas* canvas, bool antiAlias) const {
47 canvas->clipPath(fPath, SkClipOp::kIntersect, antiAlias);
48 }
49
onDraw(SkCanvas * canvas,const SkPaint & paint) const50 void GeometryEffect::onDraw(SkCanvas* canvas, const SkPaint& paint) const {
51 canvas->drawPath(fPath, paint);
52 }
53
onContains(const SkPoint & p) const54 bool GeometryEffect::onContains(const SkPoint& p) const {
55 return fPath.contains(p.x(), p.y());
56 }
57
onAsPath() const58 SkPath GeometryEffect::onAsPath() const {
59 return fPath;
60 }
61
onRevalidate(InvalidationController * ic,const SkMatrix & ctm)62 SkRect GeometryEffect::onRevalidate(InvalidationController* ic, const SkMatrix& ctm) {
63 SkASSERT(this->hasInval());
64
65 fChild->revalidate(ic, ctm);
66
67 fPath = this->onRevalidateEffect(fChild);
68 SkPathPriv::ShrinkToFit(&fPath);
69
70 return fPath.computeTightBounds();
71 }
72
onRevalidateEffect(const sk_sp<GeometryNode> & child)73 SkPath TrimEffect::onRevalidateEffect(const sk_sp<GeometryNode>& child) {
74 SkPath path = child->asPath();
75
76 if (const auto trim = SkTrimPathEffect::Make(fStart, fStop, fMode)) {
77 SkStrokeRec rec(SkStrokeRec::kHairline_InitStyle);
78 SkASSERT(!trim->needsCTM());
79 SkAssertResult(trim->filterPath(&path, path, &rec, nullptr));
80 }
81
82 return path;
83 }
84
GeometryTransform(sk_sp<GeometryNode> child,sk_sp<Transform> transform)85 GeometryTransform::GeometryTransform(sk_sp<GeometryNode> child, sk_sp<Transform> transform)
86 : INHERITED(std::move(child))
87 , fTransform(std::move(transform)) {
88 SkASSERT(fTransform);
89 this->observeInval(fTransform);
90 }
91
~GeometryTransform()92 GeometryTransform::~GeometryTransform() {
93 this->unobserveInval(fTransform);
94 }
95
onRevalidateEffect(const sk_sp<GeometryNode> & child)96 SkPath GeometryTransform::onRevalidateEffect(const sk_sp<GeometryNode>& child) {
97 fTransform->revalidate(nullptr, SkMatrix::I());
98 const auto m = TransformPriv::As<SkMatrix>(fTransform);
99
100 SkPath path = child->asPath();
101 path.transform(m);
102
103 return path;
104 }
105
106 namespace {
107
make_dash(const std::vector<float> & intervals,float phase)108 sk_sp<SkPathEffect> make_dash(const std::vector<float>& intervals, float phase) {
109 if (intervals.empty()) {
110 return nullptr;
111 }
112
113 const auto* intervals_ptr = intervals.data();
114 auto intervals_count = intervals.size();
115
116 STArray<32, float, true> storage;
117 if (intervals_count & 1) {
118 intervals_count *= 2;
119 storage.resize(intervals_count);
120 intervals_ptr = storage.data();
121
122 std::copy(intervals.begin(), intervals.end(), storage.begin());
123 std::copy(intervals.begin(), intervals.end(), storage.begin() + intervals.size());
124 }
125
126 return SkDashPathEffect::Make(intervals_ptr, SkToInt(intervals_count), phase);
127 }
128
129 } // namespace
130
onRevalidateEffect(const sk_sp<GeometryNode> & child)131 SkPath DashEffect::onRevalidateEffect(const sk_sp<GeometryNode>& child) {
132 SkPath path = child->asPath();
133
134 if (const auto dash_patheffect = make_dash(fIntervals, fPhase)) {
135 SkStrokeRec rec(SkStrokeRec::kHairline_InitStyle);
136 SkASSERT(!dash_patheffect->needsCTM());
137 dash_patheffect->filterPath(&path, path, &rec, nullptr);
138 }
139
140 return path;
141 }
142
onRevalidateEffect(const sk_sp<GeometryNode> & child)143 SkPath RoundEffect::onRevalidateEffect(const sk_sp<GeometryNode>& child) {
144 SkPath path = child->asPath();
145
146 if (const auto round = SkCornerPathEffect::Make(fRadius)) {
147 SkStrokeRec rec(SkStrokeRec::kHairline_InitStyle);
148 SkASSERT(!round->needsCTM());
149 SkAssertResult(round->filterPath(&path, path, &rec, nullptr));
150 }
151
152 return path;
153 }
154
onRevalidateEffect(const sk_sp<GeometryNode> & child)155 SkPath OffsetEffect::onRevalidateEffect(const sk_sp<GeometryNode>& child) {
156 SkPath path = child->asPath();
157
158 if (!SkScalarNearlyZero(fOffset)) {
159 SkPaint paint;
160 paint.setStyle(SkPaint::kStroke_Style);
161 paint.setStrokeWidth(std::abs(fOffset) * 2);
162 paint.setStrokeMiter(fMiterLimit);
163 paint.setStrokeJoin(fJoin);
164
165 SkPath fill_path;
166 skpathutils::FillPathWithPaint(path, paint, &fill_path, nullptr);
167
168 if (fOffset > 0) {
169 Op(path, fill_path, kUnion_SkPathOp, &path);
170 } else {
171 Op(path, fill_path, kDifference_SkPathOp, &path);
172 }
173
174 // TODO: this seems to break path combining (winding mismatch?)
175 // Simplify(path, &path);
176 }
177
178 return path;
179 }
180
181 } // namespace sksg
182