gfx/skia/trunk/src/gpu/effects/GrConvexPolyEffect.cpp@6474c204b198
gfx/skia/trunk/src/gpu/effects/GrConvexPolyEffect.cpp
Wed, 31 Dec 2014 06:09:35 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 06:09:35 +0100
- changeset 0
- 6474c204b198
- permissions
- -rw-r--r--
Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.
1 /*
2 * Copyright 2014 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 */
8 #include "GrConvexPolyEffect.h"
10 #include "gl/GrGLEffect.h"
11 #include "gl/GrGLSL.h"
12 #include "GrTBackendEffectFactory.h"
14 #include "SkPath.h"
16 //////////////////////////////////////////////////////////////////////////////
17 class GLAARectEffect;
19 class AARectEffect : public GrEffect {
20 public:
21 typedef GLAARectEffect GLEffect;
23 const SkRect& getRect() const { return fRect; }
25 static const char* Name() { return "AARect"; }
27 static GrEffectRef* Create(GrEffectEdgeType edgeType, const SkRect& rect) {
28 return CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(AARectEffect, (edgeType, rect))));
29 }
31 virtual void getConstantColorComponents(GrColor* color,
32 uint32_t* validFlags) const SK_OVERRIDE {
33 if (fRect.isEmpty()) {
34 // An empty rect will have no coverage anywhere.
35 *color = 0x00000000;
36 *validFlags = kRGBA_GrColorComponentFlags;
37 } else {
38 *validFlags = 0;
39 }
40 }
42 GrEffectEdgeType getEdgeType() const { return fEdgeType; }
44 virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE;
46 private:
47 AARectEffect(GrEffectEdgeType edgeType, const SkRect& rect) : fRect(rect), fEdgeType(edgeType) {
48 this->setWillReadFragmentPosition();
49 }
51 virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE {
52 const AARectEffect& aare = CastEffect<AARectEffect>(other);
53 return fRect == aare.fRect;
54 }
56 SkRect fRect;
57 GrEffectEdgeType fEdgeType;
59 typedef GrEffect INHERITED;
61 GR_DECLARE_EFFECT_TEST;
63 };
65 GR_DEFINE_EFFECT_TEST(AARectEffect);
67 GrEffectRef* AARectEffect::TestCreate(SkRandom* random,
68 GrContext*,
69 const GrDrawTargetCaps& caps,
70 GrTexture*[]) {
71 SkRect rect = SkRect::MakeLTRB(random->nextSScalar1(),
72 random->nextSScalar1(),
73 random->nextSScalar1(),
74 random->nextSScalar1());
75 GrEffectRef* effect;
76 do {
77 GrEffectEdgeType edgeType = static_cast<GrEffectEdgeType>(random->nextULessThan(
78 kGrEffectEdgeTypeCnt));
80 effect = AARectEffect::Create(edgeType, rect);
81 } while (NULL == effect);
82 return effect;
83 }
85 //////////////////////////////////////////////////////////////////////////////
87 class GLAARectEffect : public GrGLEffect {
88 public:
89 GLAARectEffect(const GrBackendEffectFactory&, const GrDrawEffect&);
91 virtual void emitCode(GrGLShaderBuilder* builder,
92 const GrDrawEffect& drawEffect,
93 EffectKey key,
94 const char* outputColor,
95 const char* inputColor,
96 const TransformedCoordsArray&,
97 const TextureSamplerArray&) SK_OVERRIDE;
99 static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);
101 virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
103 private:
104 GrGLUniformManager::UniformHandle fRectUniform;
105 SkRect fPrevRect;
106 typedef GrGLEffect INHERITED;
107 };
109 GLAARectEffect::GLAARectEffect(const GrBackendEffectFactory& factory,
110 const GrDrawEffect& drawEffect)
111 : INHERITED (factory) {
112 fPrevRect.fLeft = SK_ScalarNaN;
113 }
115 void GLAARectEffect::emitCode(GrGLShaderBuilder* builder,
116 const GrDrawEffect& drawEffect,
117 EffectKey key,
118 const char* outputColor,
119 const char* inputColor,
120 const TransformedCoordsArray&,
121 const TextureSamplerArray& samplers) {
122 const AARectEffect& aare = drawEffect.castEffect<AARectEffect>();
123 const char *rectName;
124 // The rect uniform's xyzw refer to (left + 0.5, top + 0.5, right - 0.5, bottom - 0.5),
125 // respectively.
126 fRectUniform = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
127 kVec4f_GrSLType,
128 "rect",
129 &rectName);
130 const char* fragmentPos = builder->fragmentPosition();
131 if (GrEffectEdgeTypeIsAA(aare.getEdgeType())) {
132 // The amount of coverage removed in x and y by the edges is computed as a pair of negative
133 // numbers, xSub and ySub.
134 builder->fsCodeAppend("\t\tfloat xSub, ySub;\n");
135 builder->fsCodeAppendf("\t\txSub = min(%s.x - %s.x, 0.0);\n", fragmentPos, rectName);
136 builder->fsCodeAppendf("\t\txSub += min(%s.z - %s.x, 0.0);\n", rectName, fragmentPos);
137 builder->fsCodeAppendf("\t\tySub = min(%s.y - %s.y, 0.0);\n", fragmentPos, rectName);
138 builder->fsCodeAppendf("\t\tySub += min(%s.w - %s.y, 0.0);\n", rectName, fragmentPos);
139 // Now compute coverage in x and y and multiply them to get the fraction of the pixel
140 // covered.
141 builder->fsCodeAppendf("\t\tfloat alpha = (1.0 + max(xSub, -1.0)) * (1.0 + max(ySub, -1.0));\n");
142 } else {
143 builder->fsCodeAppendf("\t\tfloat alpha = 1.0;\n");
144 builder->fsCodeAppendf("\t\talpha *= (%s.x - %s.x) > -0.5 ? 1.0 : 0.0;\n", fragmentPos, rectName);
145 builder->fsCodeAppendf("\t\talpha *= (%s.z - %s.x) > -0.5 ? 1.0 : 0.0;\n", rectName, fragmentPos);
146 builder->fsCodeAppendf("\t\talpha *= (%s.y - %s.y) > -0.5 ? 1.0 : 0.0;\n", fragmentPos, rectName);
147 builder->fsCodeAppendf("\t\talpha *= (%s.w - %s.y) > -0.5 ? 1.0 : 0.0;\n", rectName, fragmentPos);
148 }
150 if (GrEffectEdgeTypeIsInverseFill(aare.getEdgeType())) {
151 builder->fsCodeAppend("\t\talpha = 1.0 - alpha;\n");
152 }
153 builder->fsCodeAppendf("\t\t%s = %s;\n", outputColor,
154 (GrGLSLExpr4(inputColor) * GrGLSLExpr1("alpha")).c_str());
155 }
157 void GLAARectEffect::setData(const GrGLUniformManager& uman, const GrDrawEffect& drawEffect) {
158 const AARectEffect& aare = drawEffect.castEffect<AARectEffect>();
159 const SkRect& rect = aare.getRect();
160 if (rect != fPrevRect) {
161 uman.set4f(fRectUniform, rect.fLeft + 0.5f, rect.fTop + 0.5f,
162 rect.fRight - 0.5f, rect.fBottom - 0.5f);
163 fPrevRect = rect;
164 }
165 }
167 GrGLEffect::EffectKey GLAARectEffect::GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) {
168 const AARectEffect& aare = drawEffect.castEffect<AARectEffect>();
169 return aare.getEdgeType();
170 }
172 const GrBackendEffectFactory& AARectEffect::getFactory() const {
173 return GrTBackendEffectFactory<AARectEffect>::getInstance();
174 }
176 //////////////////////////////////////////////////////////////////////////////
178 class GrGLConvexPolyEffect : public GrGLEffect {
179 public:
180 GrGLConvexPolyEffect(const GrBackendEffectFactory&, const GrDrawEffect&);
182 virtual void emitCode(GrGLShaderBuilder* builder,
183 const GrDrawEffect& drawEffect,
184 EffectKey key,
185 const char* outputColor,
186 const char* inputColor,
187 const TransformedCoordsArray&,
188 const TextureSamplerArray&) SK_OVERRIDE;
190 static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);
192 virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
194 private:
195 GrGLUniformManager::UniformHandle fEdgeUniform;
196 SkScalar fPrevEdges[3 * GrConvexPolyEffect::kMaxEdges];
197 typedef GrGLEffect INHERITED;
198 };
200 GrGLConvexPolyEffect::GrGLConvexPolyEffect(const GrBackendEffectFactory& factory,
201 const GrDrawEffect& drawEffect)
202 : INHERITED (factory) {
203 fPrevEdges[0] = SK_ScalarNaN;
204 }
206 void GrGLConvexPolyEffect::emitCode(GrGLShaderBuilder* builder,
207 const GrDrawEffect& drawEffect,
208 EffectKey key,
209 const char* outputColor,
210 const char* inputColor,
211 const TransformedCoordsArray&,
212 const TextureSamplerArray& samplers) {
213 const GrConvexPolyEffect& cpe = drawEffect.castEffect<GrConvexPolyEffect>();
215 const char *edgeArrayName;
216 fEdgeUniform = builder->addUniformArray(GrGLShaderBuilder::kFragment_Visibility,
217 kVec3f_GrSLType,
218 "edges",
219 cpe.getEdgeCount(),
220 &edgeArrayName);
221 builder->fsCodeAppend("\t\tfloat alpha = 1.0;\n");
222 builder->fsCodeAppend("\t\tfloat edge;\n");
223 const char* fragmentPos = builder->fragmentPosition();
224 for (int i = 0; i < cpe.getEdgeCount(); ++i) {
225 builder->fsCodeAppendf("\t\tedge = dot(%s[%d], vec3(%s.x, %s.y, 1));\n",
226 edgeArrayName, i, fragmentPos, fragmentPos);
227 if (GrEffectEdgeTypeIsAA(cpe.getEdgeType())) {
228 builder->fsCodeAppend("\t\tedge = clamp(edge, 0.0, 1.0);\n");
229 } else {
230 builder->fsCodeAppend("\t\tedge = edge >= 0.5 ? 1.0 : 0.0;\n");
231 }
232 builder->fsCodeAppend("\t\talpha *= edge;\n");
233 }
235 // Woe is me. See skbug.com/2149.
236 if (kTegra2_GrGLRenderer == builder->ctxInfo().renderer()) {
237 builder->fsCodeAppend("\t\tif (-1.0 == alpha) {\n\t\t\tdiscard;\n\t\t}\n");
238 }
240 if (GrEffectEdgeTypeIsInverseFill(cpe.getEdgeType())) {
241 builder->fsCodeAppend("\talpha = 1.0 - alpha;\n");
242 }
243 builder->fsCodeAppendf("\t%s = %s;\n", outputColor,
244 (GrGLSLExpr4(inputColor) * GrGLSLExpr1("alpha")).c_str());
245 }
247 void GrGLConvexPolyEffect::setData(const GrGLUniformManager& uman, const GrDrawEffect& drawEffect) {
248 const GrConvexPolyEffect& cpe = drawEffect.castEffect<GrConvexPolyEffect>();
249 size_t byteSize = 3 * cpe.getEdgeCount() * sizeof(SkScalar);
250 if (0 != memcmp(fPrevEdges, cpe.getEdges(), byteSize)) {
251 uman.set3fv(fEdgeUniform, cpe.getEdgeCount(), cpe.getEdges());
252 memcpy(fPrevEdges, cpe.getEdges(), byteSize);
253 }
254 }
256 GrGLEffect::EffectKey GrGLConvexPolyEffect::GenKey(const GrDrawEffect& drawEffect,
257 const GrGLCaps&) {
258 const GrConvexPolyEffect& cpe = drawEffect.castEffect<GrConvexPolyEffect>();
259 GR_STATIC_ASSERT(kGrEffectEdgeTypeCnt <= 8);
260 return (cpe.getEdgeCount() << 3) | cpe.getEdgeType();
261 }
263 //////////////////////////////////////////////////////////////////////////////
265 GrEffectRef* GrConvexPolyEffect::Create(GrEffectEdgeType type, const SkPath& path, const SkVector* offset) {
266 if (kHairlineAA_GrEffectEdgeType == type) {
267 return NULL;
268 }
269 if (path.getSegmentMasks() != SkPath::kLine_SegmentMask ||
270 !path.isConvex()) {
271 return NULL;
272 }
274 if (path.countPoints() > kMaxEdges) {
275 return NULL;
276 }
278 SkPoint pts[kMaxEdges];
279 SkScalar edges[3 * kMaxEdges];
281 SkPath::Direction dir;
282 SkAssertResult(path.cheapComputeDirection(&dir));
284 SkVector t;
285 if (NULL == offset) {
286 t.set(0, 0);
287 } else {
288 t = *offset;
289 }
291 int count = path.getPoints(pts, kMaxEdges);
292 int n = 0;
293 for (int lastPt = count - 1, i = 0; i < count; lastPt = i++) {
294 if (pts[lastPt] != pts[i]) {
295 SkVector v = pts[i] - pts[lastPt];
296 v.normalize();
297 if (SkPath::kCCW_Direction == dir) {
298 edges[3 * n] = v.fY;
299 edges[3 * n + 1] = -v.fX;
300 } else {
301 edges[3 * n] = -v.fY;
302 edges[3 * n + 1] = v.fX;
303 }
304 SkPoint p = pts[i] + t;
305 edges[3 * n + 2] = -(edges[3 * n] * p.fX + edges[3 * n + 1] * p.fY);
306 ++n;
307 }
308 }
309 if (path.isInverseFillType()) {
310 type = GrInvertEffectEdgeType(type);
311 }
312 return Create(type, n, edges);
313 }
315 GrEffectRef* GrConvexPolyEffect::Create(GrEffectEdgeType edgeType, const SkRect& rect) {
316 if (kHairlineAA_GrEffectEdgeType == edgeType){
317 return NULL;
318 }
319 return AARectEffect::Create(edgeType, rect);
320 }
322 GrConvexPolyEffect::~GrConvexPolyEffect() {}
324 void GrConvexPolyEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
325 *validFlags = 0;
326 }
328 const GrBackendEffectFactory& GrConvexPolyEffect::getFactory() const {
329 return GrTBackendEffectFactory<GrConvexPolyEffect>::getInstance();
330 }
332 GrConvexPolyEffect::GrConvexPolyEffect(GrEffectEdgeType edgeType, int n, const SkScalar edges[])
333 : fEdgeType(edgeType)
334 , fEdgeCount(n) {
335 // Factory function should have already ensured this.
336 SkASSERT(n <= kMaxEdges);
337 memcpy(fEdges, edges, 3 * n * sizeof(SkScalar));
338 // Outset the edges by 0.5 so that a pixel with center on an edge is 50% covered in the AA case
339 // and 100% covered in the non-AA case.
340 for (int i = 0; i < n; ++i) {
341 fEdges[3 * i + 2] += SK_ScalarHalf;
342 }
343 this->setWillReadFragmentPosition();
344 }
346 bool GrConvexPolyEffect::onIsEqual(const GrEffect& other) const {
347 const GrConvexPolyEffect& cpe = CastEffect<GrConvexPolyEffect>(other);
348 // ignore the fact that 0 == -0 and just use memcmp.
349 return (cpe.fEdgeType == fEdgeType && cpe.fEdgeCount == fEdgeCount &&
350 0 == memcmp(cpe.fEdges, fEdges, 3 * fEdgeCount * sizeof(SkScalar)));
351 }
353 //////////////////////////////////////////////////////////////////////////////
355 GR_DEFINE_EFFECT_TEST(GrConvexPolyEffect);
357 GrEffectRef* GrConvexPolyEffect::TestCreate(SkRandom* random,
358 GrContext*,
359 const GrDrawTargetCaps& caps,
360 GrTexture*[]) {
361 int count = random->nextULessThan(kMaxEdges) + 1;
362 SkScalar edges[kMaxEdges * 3];
363 for (int i = 0; i < 3 * count; ++i) {
364 edges[i] = random->nextSScalar1();
365 }
367 GrEffectRef* effect;
368 do {
369 GrEffectEdgeType edgeType = static_cast<GrEffectEdgeType>(
370 random->nextULessThan(kGrEffectEdgeTypeCnt));
371 effect = GrConvexPolyEffect::Create(edgeType, count, edges);
372 } while (NULL == effect);
373 return effect;
374 }
