1 /*
2 * Copyright 2019 Google LLC
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/particles/include/SkParticleDrawable.h"
9
10 #include "include/core/SkCanvas.h"
11 #include "include/core/SkImage.h"
12 #include "include/core/SkPaint.h"
13 #include "include/core/SkRSXform.h"
14 #include "include/core/SkRect.h"
15 #include "include/core/SkString.h"
16 #include "include/core/SkSurface.h"
17 #include "modules/particles/include/SkParticleData.h"
18 #include "src/core/SkAutoMalloc.h"
19
make_circle_image(int radius)20 static sk_sp<SkImage> make_circle_image(int radius) {
21 auto surface = SkSurface::MakeRasterN32Premul(radius * 2, radius * 2);
22 surface->getCanvas()->clear(SK_ColorTRANSPARENT);
23 SkPaint paint;
24 paint.setAntiAlias(true);
25 paint.setColor(SK_ColorWHITE);
26 surface->getCanvas()->drawCircle(radius, radius, radius, paint);
27 return surface->makeImageSnapshot();
28 }
29
make_rsxform(SkPoint ofs,float posX,float posY,float dirX,float dirY,float scale)30 static inline SkRSXform make_rsxform(SkPoint ofs,
31 float posX, float posY, float dirX, float dirY, float scale) {
32 const float s = dirX * scale;
33 const float c = -dirY * scale;
34 return SkRSXform::Make(c, s,
35 posX + -c * ofs.fX + s * ofs.fY,
36 posY + -s * ofs.fX + -c * ofs.fY);
37 }
38
39 struct DrawAtlasArrays {
DrawAtlasArraysDrawAtlasArrays40 DrawAtlasArrays(const SkParticles& particles, int count, SkPoint center)
41 : fXforms(count)
42 , fRects(count)
43 , fColors(count) {
44 float* c[] = {
45 particles.fData[SkParticles::kColorR].get(),
46 particles.fData[SkParticles::kColorG].get(),
47 particles.fData[SkParticles::kColorB].get(),
48 particles.fData[SkParticles::kColorA].get(),
49 };
50
51 float* pos[] = {
52 particles.fData[SkParticles::kPositionX].get(),
53 particles.fData[SkParticles::kPositionY].get(),
54 };
55 float* dir[] = {
56 particles.fData[SkParticles::kHeadingX].get(),
57 particles.fData[SkParticles::kHeadingY].get(),
58 };
59 float* scale = particles.fData[SkParticles::kScale].get();
60
61 for (int i = 0; i < count; ++i) {
62 fXforms[i] = make_rsxform(center, pos[0][i], pos[1][i], dir[0][i], dir[1][i], scale[i]);
63 fColors[i] = SkColor4f{ c[0][i], c[1][i], c[2][i], c[3][i] }.toSkColor();
64 }
65 }
66
67 SkAutoTMalloc<SkRSXform> fXforms;
68 SkAutoTMalloc<SkRect> fRects;
69 SkAutoTMalloc<SkColor> fColors;
70 };
71
72 class SkCircleDrawable : public SkParticleDrawable {
73 public:
SkCircleDrawable(int radius=1)74 SkCircleDrawable(int radius = 1)
75 : fRadius(radius) {
76 this->rebuild();
77 }
78
REFLECTED(SkCircleDrawable,SkParticleDrawable)79 REFLECTED(SkCircleDrawable, SkParticleDrawable)
80
81 void draw(SkCanvas* canvas, const SkParticles& particles, int count,
82 const SkPaint* paint) override {
83 SkPoint center = { SkIntToScalar(fRadius), SkIntToScalar(fRadius) };
84 DrawAtlasArrays arrays(particles, count, center);
85 for (int i = 0; i < count; ++i) {
86 arrays.fRects[i].set(0.0f, 0.0f, fImage->width(), fImage->height());
87 }
88 canvas->drawAtlas(fImage, arrays.fXforms.get(), arrays.fRects.get(), arrays.fColors.get(),
89 count, SkBlendMode::kModulate, nullptr, paint);
90 }
91
visitFields(SkFieldVisitor * v)92 void visitFields(SkFieldVisitor* v) override {
93 v->visit("Radius", fRadius);
94 this->rebuild();
95 }
96
97 private:
98 int fRadius;
99
rebuild()100 void rebuild() {
101 fRadius = SkTMax(fRadius, 1);
102 if (!fImage || fImage->width() != 2 * fRadius) {
103 fImage = make_circle_image(fRadius);
104 }
105 }
106
107 // Cached
108 sk_sp<SkImage> fImage;
109 };
110
111 class SkImageDrawable : public SkParticleDrawable {
112 public:
SkImageDrawable(const SkString & path=SkString (),int cols=1,int rows=1)113 SkImageDrawable(const SkString& path = SkString(), int cols = 1, int rows = 1)
114 : fPath(path)
115 , fCols(cols)
116 , fRows(rows) {
117 this->rebuild();
118 }
119
REFLECTED(SkImageDrawable,SkParticleDrawable)120 REFLECTED(SkImageDrawable, SkParticleDrawable)
121
122 void draw(SkCanvas* canvas, const SkParticles& particles, int count,
123 const SkPaint* paint) override {
124 SkRect baseRect = getBaseRect();
125 SkPoint center = { baseRect.width() * 0.5f, baseRect.height() * 0.5f };
126 DrawAtlasArrays arrays(particles, count, center);
127
128 int frameCount = fCols * fRows;
129 float* spriteFrames = particles.fData[SkParticles::kSpriteFrame].get();
130 for (int i = 0; i < count; ++i) {
131 int frame = static_cast<int>(spriteFrames[i] * frameCount + 0.5f);
132 frame = SkTPin(frame, 0, frameCount - 1);
133 int row = frame / fCols;
134 int col = frame % fCols;
135 arrays.fRects[i] = baseRect.makeOffset(col * baseRect.width(), row * baseRect.height());
136 }
137 canvas->drawAtlas(fImage, arrays.fXforms.get(), arrays.fRects.get(), arrays.fColors.get(),
138 count, SkBlendMode::kModulate, nullptr, paint);
139 }
140
visitFields(SkFieldVisitor * v)141 void visitFields(SkFieldVisitor* v) override {
142 SkString oldPath = fPath;
143
144 v->visit("Path", fPath);
145 v->visit("Columns", fCols);
146 v->visit("Rows", fRows);
147
148 fCols = SkTMax(fCols, 1);
149 fRows = SkTMax(fRows, 1);
150 if (oldPath != fPath) {
151 this->rebuild();
152 }
153 }
154
155 private:
156 SkString fPath;
157 int fCols;
158 int fRows;
159
getBaseRect() const160 SkRect getBaseRect() const {
161 return SkRect::MakeWH(static_cast<float>(fImage->width()) / fCols,
162 static_cast<float>(fImage->height() / fRows));
163 }
164
rebuild()165 void rebuild() {
166 fImage = SkImage::MakeFromEncoded(SkData::MakeFromFileName(fPath.c_str()));
167 if (!fImage) {
168 if (!fPath.isEmpty()) {
169 SkDebugf("Could not load image \"%s\"\n", fPath.c_str());
170 }
171 fImage = make_circle_image(1);
172 }
173 }
174
175 // Cached
176 sk_sp<SkImage> fImage;
177 };
178
RegisterDrawableTypes()179 void SkParticleDrawable::RegisterDrawableTypes() {
180 REGISTER_REFLECTED(SkParticleDrawable);
181 REGISTER_REFLECTED(SkCircleDrawable);
182 REGISTER_REFLECTED(SkImageDrawable);
183 }
184
MakeCircle(int radius)185 sk_sp<SkParticleDrawable> SkParticleDrawable::MakeCircle(int radius) {
186 return sk_sp<SkParticleDrawable>(new SkCircleDrawable(radius));
187 }
188
MakeImage(const SkString & path,int cols,int rows)189 sk_sp<SkParticleDrawable> SkParticleDrawable::MakeImage(const SkString& path, int cols, int rows) {
190 return sk_sp<SkParticleDrawable>(new SkImageDrawable(path, cols, rows));
191 }
192