gfx/skia/trunk/src/gpu/GrOvalRenderer.cpp@129ffea94266
gfx/skia/trunk/src/gpu/GrOvalRenderer.cpp
Sat, 03 Jan 2015 20:18:00 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Sat, 03 Jan 2015 20:18:00 +0100
- branch
- TOR_BUG_3246
- changeset 7
- 129ffea94266
- permissions
- -rw-r--r--
Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.
1 /*
2 * Copyright 2013 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 "GrOvalRenderer.h"
10 #include "GrEffect.h"
11 #include "gl/GrGLEffect.h"
12 #include "gl/GrGLSL.h"
13 #include "gl/GrGLVertexEffect.h"
14 #include "GrTBackendEffectFactory.h"
16 #include "GrDrawState.h"
17 #include "GrDrawTarget.h"
18 #include "GrGpu.h"
20 #include "SkRRect.h"
21 #include "SkStrokeRec.h"
23 #include "effects/GrVertexEffect.h"
25 namespace {
27 struct CircleVertex {
28 GrPoint fPos;
29 GrPoint fOffset;
30 SkScalar fOuterRadius;
31 SkScalar fInnerRadius;
32 };
34 struct EllipseVertex {
35 GrPoint fPos;
36 GrPoint fOffset;
37 GrPoint fOuterRadii;
38 GrPoint fInnerRadii;
39 };
41 struct DIEllipseVertex {
42 GrPoint fPos;
43 GrPoint fOuterOffset;
44 GrPoint fInnerOffset;
45 };
47 inline bool circle_stays_circle(const SkMatrix& m) {
48 return m.isSimilarity();
49 }
51 }
53 ///////////////////////////////////////////////////////////////////////////////
55 /**
56 * The output of this effect is a modulation of the input color and coverage for a circle,
57 * specified as offset_x, offset_y (both from center point), outer radius and inner radius.
58 */
60 class CircleEdgeEffect : public GrVertexEffect {
61 public:
62 static GrEffectRef* Create(bool stroke) {
63 GR_CREATE_STATIC_EFFECT(gCircleStrokeEdge, CircleEdgeEffect, (true));
64 GR_CREATE_STATIC_EFFECT(gCircleFillEdge, CircleEdgeEffect, (false));
66 if (stroke) {
67 gCircleStrokeEdge->ref();
68 return gCircleStrokeEdge;
69 } else {
70 gCircleFillEdge->ref();
71 return gCircleFillEdge;
72 }
73 }
75 virtual void getConstantColorComponents(GrColor* color,
76 uint32_t* validFlags) const SK_OVERRIDE {
77 *validFlags = 0;
78 }
80 virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE {
81 return GrTBackendEffectFactory<CircleEdgeEffect>::getInstance();
82 }
84 virtual ~CircleEdgeEffect() {}
86 static const char* Name() { return "CircleEdge"; }
88 inline bool isStroked() const { return fStroke; }
90 class GLEffect : public GrGLVertexEffect {
91 public:
92 GLEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&)
93 : INHERITED (factory) {}
95 virtual void emitCode(GrGLFullShaderBuilder* builder,
96 const GrDrawEffect& drawEffect,
97 EffectKey key,
98 const char* outputColor,
99 const char* inputColor,
100 const TransformedCoordsArray&,
101 const TextureSamplerArray& samplers) SK_OVERRIDE {
102 const CircleEdgeEffect& circleEffect = drawEffect.castEffect<CircleEdgeEffect>();
103 const char *vsName, *fsName;
104 builder->addVarying(kVec4f_GrSLType, "CircleEdge", &vsName, &fsName);
106 const SkString* attrName =
107 builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[0]);
108 builder->vsCodeAppendf("\t%s = %s;\n", vsName, attrName->c_str());
110 builder->fsCodeAppendf("\tfloat d = length(%s.xy);\n", fsName);
111 builder->fsCodeAppendf("\tfloat edgeAlpha = clamp(%s.z - d, 0.0, 1.0);\n", fsName);
112 if (circleEffect.isStroked()) {
113 builder->fsCodeAppendf("\tfloat innerAlpha = clamp(d - %s.w, 0.0, 1.0);\n", fsName);
114 builder->fsCodeAppend("\tedgeAlpha *= innerAlpha;\n");
115 }
117 builder->fsCodeAppendf("\t%s = %s;\n", outputColor,
118 (GrGLSLExpr4(inputColor) * GrGLSLExpr1("edgeAlpha")).c_str());
119 }
121 static inline EffectKey GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) {
122 const CircleEdgeEffect& circleEffect = drawEffect.castEffect<CircleEdgeEffect>();
124 return circleEffect.isStroked() ? 0x1 : 0x0;
125 }
127 virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE {}
129 private:
130 typedef GrGLVertexEffect INHERITED;
131 };
134 private:
135 CircleEdgeEffect(bool stroke) : GrVertexEffect() {
136 this->addVertexAttrib(kVec4f_GrSLType);
137 fStroke = stroke;
138 }
140 virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE {
141 const CircleEdgeEffect& cee = CastEffect<CircleEdgeEffect>(other);
142 return cee.fStroke == fStroke;
143 }
145 bool fStroke;
147 GR_DECLARE_EFFECT_TEST;
149 typedef GrVertexEffect INHERITED;
150 };
152 GR_DEFINE_EFFECT_TEST(CircleEdgeEffect);
154 GrEffectRef* CircleEdgeEffect::TestCreate(SkRandom* random,
155 GrContext* context,
156 const GrDrawTargetCaps&,
157 GrTexture* textures[]) {
158 return CircleEdgeEffect::Create(random->nextBool());
159 }
161 ///////////////////////////////////////////////////////////////////////////////
163 /**
164 * The output of this effect is a modulation of the input color and coverage for an axis-aligned
165 * ellipse, specified as a 2D offset from center, and the reciprocals of the outer and inner radii,
166 * in both x and y directions.
167 *
168 * We are using an implicit function of x^2/a^2 + y^2/b^2 - 1 = 0.
169 */
171 class EllipseEdgeEffect : public GrVertexEffect {
172 public:
173 static GrEffectRef* Create(bool stroke) {
174 GR_CREATE_STATIC_EFFECT(gEllipseStrokeEdge, EllipseEdgeEffect, (true));
175 GR_CREATE_STATIC_EFFECT(gEllipseFillEdge, EllipseEdgeEffect, (false));
177 if (stroke) {
178 gEllipseStrokeEdge->ref();
179 return gEllipseStrokeEdge;
180 } else {
181 gEllipseFillEdge->ref();
182 return gEllipseFillEdge;
183 }
184 }
186 virtual void getConstantColorComponents(GrColor* color,
187 uint32_t* validFlags) const SK_OVERRIDE {
188 *validFlags = 0;
189 }
191 virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE {
192 return GrTBackendEffectFactory<EllipseEdgeEffect>::getInstance();
193 }
195 virtual ~EllipseEdgeEffect() {}
197 static const char* Name() { return "EllipseEdge"; }
199 inline bool isStroked() const { return fStroke; }
201 class GLEffect : public GrGLVertexEffect {
202 public:
203 GLEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&)
204 : INHERITED (factory) {}
206 virtual void emitCode(GrGLFullShaderBuilder* builder,
207 const GrDrawEffect& drawEffect,
208 EffectKey key,
209 const char* outputColor,
210 const char* inputColor,
211 const TransformedCoordsArray&,
212 const TextureSamplerArray& samplers) SK_OVERRIDE {
213 const EllipseEdgeEffect& ellipseEffect = drawEffect.castEffect<EllipseEdgeEffect>();
215 const char *vsOffsetName, *fsOffsetName;
216 const char *vsRadiiName, *fsRadiiName;
218 builder->addVarying(kVec2f_GrSLType, "EllipseOffsets", &vsOffsetName, &fsOffsetName);
219 const SkString* attr0Name =
220 builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[0]);
221 builder->vsCodeAppendf("\t%s = %s;\n", vsOffsetName, attr0Name->c_str());
223 builder->addVarying(kVec4f_GrSLType, "EllipseRadii", &vsRadiiName, &fsRadiiName);
224 const SkString* attr1Name =
225 builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[1]);
226 builder->vsCodeAppendf("\t%s = %s;\n", vsRadiiName, attr1Name->c_str());
228 // for outer curve
229 builder->fsCodeAppendf("\tvec2 scaledOffset = %s*%s.xy;\n", fsOffsetName, fsRadiiName);
230 builder->fsCodeAppend("\tfloat test = dot(scaledOffset, scaledOffset) - 1.0;\n");
231 builder->fsCodeAppendf("\tvec2 grad = 2.0*scaledOffset*%s.xy;\n", fsRadiiName);
232 builder->fsCodeAppend("\tfloat grad_dot = dot(grad, grad);\n");
233 // we need to clamp the length^2 of the gradiant vector to a non-zero value, because
234 // on the Nexus 4 the undefined result of inversesqrt(0) drops out an entire tile
235 // TODO: restrict this to Adreno-only
236 builder->fsCodeAppend("\tgrad_dot = max(grad_dot, 1.0e-4);\n");
237 builder->fsCodeAppend("\tfloat invlen = inversesqrt(grad_dot);\n");
238 builder->fsCodeAppend("\tfloat edgeAlpha = clamp(0.5-test*invlen, 0.0, 1.0);\n");
240 // for inner curve
241 if (ellipseEffect.isStroked()) {
242 builder->fsCodeAppendf("\tscaledOffset = %s*%s.zw;\n", fsOffsetName, fsRadiiName);
243 builder->fsCodeAppend("\ttest = dot(scaledOffset, scaledOffset) - 1.0;\n");
244 builder->fsCodeAppendf("\tgrad = 2.0*scaledOffset*%s.zw;\n", fsRadiiName);
245 builder->fsCodeAppend("\tinvlen = inversesqrt(dot(grad, grad));\n");
246 builder->fsCodeAppend("\tedgeAlpha *= clamp(0.5+test*invlen, 0.0, 1.0);\n");
247 }
249 builder->fsCodeAppendf("\t%s = %s;\n", outputColor,
250 (GrGLSLExpr4(inputColor) * GrGLSLExpr1("edgeAlpha")).c_str());
251 }
253 static inline EffectKey GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) {
254 const EllipseEdgeEffect& ellipseEffect = drawEffect.castEffect<EllipseEdgeEffect>();
256 return ellipseEffect.isStroked() ? 0x1 : 0x0;
257 }
259 virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE {
260 }
262 private:
263 typedef GrGLVertexEffect INHERITED;
264 };
266 private:
267 EllipseEdgeEffect(bool stroke) : GrVertexEffect() {
268 this->addVertexAttrib(kVec2f_GrSLType);
269 this->addVertexAttrib(kVec4f_GrSLType);
270 fStroke = stroke;
271 }
273 virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE {
274 const EllipseEdgeEffect& eee = CastEffect<EllipseEdgeEffect>(other);
275 return eee.fStroke == fStroke;
276 }
278 bool fStroke;
280 GR_DECLARE_EFFECT_TEST;
282 typedef GrVertexEffect INHERITED;
283 };
285 GR_DEFINE_EFFECT_TEST(EllipseEdgeEffect);
287 GrEffectRef* EllipseEdgeEffect::TestCreate(SkRandom* random,
288 GrContext* context,
289 const GrDrawTargetCaps&,
290 GrTexture* textures[]) {
291 return EllipseEdgeEffect::Create(random->nextBool());
292 }
294 ///////////////////////////////////////////////////////////////////////////////
296 /**
297 * The output of this effect is a modulation of the input color and coverage for an ellipse,
298 * specified as a 2D offset from center for both the outer and inner paths (if stroked). The
299 * implict equation used is for a unit circle (x^2 + y^2 - 1 = 0) and the edge corrected by
300 * using differentials.
301 *
302 * The result is device-independent and can be used with any affine matrix.
303 */
305 class DIEllipseEdgeEffect : public GrVertexEffect {
306 public:
307 enum Mode { kStroke = 0, kHairline, kFill };
309 static GrEffectRef* Create(Mode mode) {
310 GR_CREATE_STATIC_EFFECT(gEllipseStrokeEdge, DIEllipseEdgeEffect, (kStroke));
311 GR_CREATE_STATIC_EFFECT(gEllipseHairlineEdge, DIEllipseEdgeEffect, (kHairline));
312 GR_CREATE_STATIC_EFFECT(gEllipseFillEdge, DIEllipseEdgeEffect, (kFill));
314 if (kStroke == mode) {
315 gEllipseStrokeEdge->ref();
316 return gEllipseStrokeEdge;
317 } else if (kHairline == mode) {
318 gEllipseHairlineEdge->ref();
319 return gEllipseHairlineEdge;
320 } else {
321 gEllipseFillEdge->ref();
322 return gEllipseFillEdge;
323 }
324 }
326 virtual void getConstantColorComponents(GrColor* color,
327 uint32_t* validFlags) const SK_OVERRIDE {
328 *validFlags = 0;
329 }
331 virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE {
332 return GrTBackendEffectFactory<DIEllipseEdgeEffect>::getInstance();
333 }
335 virtual ~DIEllipseEdgeEffect() {}
337 static const char* Name() { return "DIEllipseEdge"; }
339 inline Mode getMode() const { return fMode; }
341 class GLEffect : public GrGLVertexEffect {
342 public:
343 GLEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&)
344 : INHERITED (factory) {}
346 virtual void emitCode(GrGLFullShaderBuilder* builder,
347 const GrDrawEffect& drawEffect,
348 EffectKey key,
349 const char* outputColor,
350 const char* inputColor,
351 const TransformedCoordsArray&,
352 const TextureSamplerArray& samplers) SK_OVERRIDE {
353 const DIEllipseEdgeEffect& ellipseEffect = drawEffect.castEffect<DIEllipseEdgeEffect>();
355 SkAssertResult(builder->enableFeature(
356 GrGLShaderBuilder::kStandardDerivatives_GLSLFeature));
358 const char *vsOffsetName0, *fsOffsetName0;
359 builder->addVarying(kVec2f_GrSLType, "EllipseOffsets0",
360 &vsOffsetName0, &fsOffsetName0);
361 const SkString* attr0Name =
362 builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[0]);
363 builder->vsCodeAppendf("\t%s = %s;\n", vsOffsetName0, attr0Name->c_str());
364 const char *vsOffsetName1, *fsOffsetName1;
365 builder->addVarying(kVec2f_GrSLType, "EllipseOffsets1",
366 &vsOffsetName1, &fsOffsetName1);
367 const SkString* attr1Name =
368 builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[1]);
369 builder->vsCodeAppendf("\t%s = %s;\n", vsOffsetName1, attr1Name->c_str());
371 // for outer curve
372 builder->fsCodeAppendf("\tvec2 scaledOffset = %s.xy;\n", fsOffsetName0);
373 builder->fsCodeAppend("\tfloat test = dot(scaledOffset, scaledOffset) - 1.0;\n");
374 builder->fsCodeAppendf("\tvec2 duvdx = dFdx(%s);\n", fsOffsetName0);
375 builder->fsCodeAppendf("\tvec2 duvdy = dFdy(%s);\n", fsOffsetName0);
376 builder->fsCodeAppendf("\tvec2 grad = vec2(2.0*%s.x*duvdx.x + 2.0*%s.y*duvdx.y,\n"
377 "\t 2.0*%s.x*duvdy.x + 2.0*%s.y*duvdy.y);\n",
378 fsOffsetName0, fsOffsetName0, fsOffsetName0, fsOffsetName0);
380 builder->fsCodeAppend("\tfloat grad_dot = dot(grad, grad);\n");
381 // we need to clamp the length^2 of the gradiant vector to a non-zero value, because
382 // on the Nexus 4 the undefined result of inversesqrt(0) drops out an entire tile
383 // TODO: restrict this to Adreno-only
384 builder->fsCodeAppend("\tgrad_dot = max(grad_dot, 1.0e-4);\n");
385 builder->fsCodeAppend("\tfloat invlen = inversesqrt(grad_dot);\n");
386 if (kHairline == ellipseEffect.getMode()) {
387 // can probably do this with one step
388 builder->fsCodeAppend("\tfloat edgeAlpha = clamp(1.0-test*invlen, 0.0, 1.0);\n");
389 builder->fsCodeAppend("\tedgeAlpha *= clamp(1.0+test*invlen, 0.0, 1.0);\n");
390 } else {
391 builder->fsCodeAppend("\tfloat edgeAlpha = clamp(0.5-test*invlen, 0.0, 1.0);\n");
392 }
394 // for inner curve
395 if (kStroke == ellipseEffect.getMode()) {
396 builder->fsCodeAppendf("\tscaledOffset = %s.xy;\n", fsOffsetName1);
397 builder->fsCodeAppend("\ttest = dot(scaledOffset, scaledOffset) - 1.0;\n");
398 builder->fsCodeAppendf("\tduvdx = dFdx(%s);\n", fsOffsetName1);
399 builder->fsCodeAppendf("\tduvdy = dFdy(%s);\n", fsOffsetName1);
400 builder->fsCodeAppendf("\tgrad = vec2(2.0*%s.x*duvdx.x + 2.0*%s.y*duvdx.y,\n"
401 "\t 2.0*%s.x*duvdy.x + 2.0*%s.y*duvdy.y);\n",
402 fsOffsetName1, fsOffsetName1, fsOffsetName1, fsOffsetName1);
403 builder->fsCodeAppend("\tinvlen = inversesqrt(dot(grad, grad));\n");
404 builder->fsCodeAppend("\tedgeAlpha *= clamp(0.5+test*invlen, 0.0, 1.0);\n");
405 }
407 builder->fsCodeAppendf("\t%s = %s;\n", outputColor,
408 (GrGLSLExpr4(inputColor) * GrGLSLExpr1("edgeAlpha")).c_str());
409 }
411 static inline EffectKey GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) {
412 const DIEllipseEdgeEffect& ellipseEffect = drawEffect.castEffect<DIEllipseEdgeEffect>();
414 return ellipseEffect.getMode();
415 }
417 virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE {
418 }
420 private:
421 typedef GrGLVertexEffect INHERITED;
422 };
424 private:
425 DIEllipseEdgeEffect(Mode mode) : GrVertexEffect() {
426 this->addVertexAttrib(kVec2f_GrSLType);
427 this->addVertexAttrib(kVec2f_GrSLType);
428 fMode = mode;
429 }
431 virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE {
432 const DIEllipseEdgeEffect& eee = CastEffect<DIEllipseEdgeEffect>(other);
433 return eee.fMode == fMode;
434 }
436 Mode fMode;
438 GR_DECLARE_EFFECT_TEST;
440 typedef GrVertexEffect INHERITED;
441 };
443 GR_DEFINE_EFFECT_TEST(DIEllipseEdgeEffect);
445 GrEffectRef* DIEllipseEdgeEffect::TestCreate(SkRandom* random,
446 GrContext* context,
447 const GrDrawTargetCaps&,
448 GrTexture* textures[]) {
449 return DIEllipseEdgeEffect::Create((Mode)(random->nextRangeU(0,2)));
450 }
452 ///////////////////////////////////////////////////////////////////////////////
454 void GrOvalRenderer::reset() {
455 SkSafeSetNull(fRRectIndexBuffer);
456 }
458 bool GrOvalRenderer::drawOval(GrDrawTarget* target, const GrContext* context, bool useAA,
459 const SkRect& oval, const SkStrokeRec& stroke)
460 {
461 bool useCoverageAA = useAA &&
462 !target->getDrawState().getRenderTarget()->isMultisampled() &&
463 !target->shouldDisableCoverageAAForBlend();
465 if (!useCoverageAA) {
466 return false;
467 }
469 const SkMatrix& vm = context->getMatrix();
471 // we can draw circles
472 if (SkScalarNearlyEqual(oval.width(), oval.height())
473 && circle_stays_circle(vm)) {
474 this->drawCircle(target, useCoverageAA, oval, stroke);
475 // if we have shader derivative support, render as device-independent
476 } else if (target->caps()->shaderDerivativeSupport()) {
477 return this->drawDIEllipse(target, useCoverageAA, oval, stroke);
478 // otherwise axis-aligned ellipses only
479 } else if (vm.rectStaysRect()) {
480 return this->drawEllipse(target, useCoverageAA, oval, stroke);
481 } else {
482 return false;
483 }
485 return true;
486 }
488 ///////////////////////////////////////////////////////////////////////////////
490 // position + edge
491 extern const GrVertexAttrib gCircleVertexAttribs[] = {
492 {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding},
493 {kVec4f_GrVertexAttribType, sizeof(GrPoint), kEffect_GrVertexAttribBinding}
494 };
496 void GrOvalRenderer::drawCircle(GrDrawTarget* target,
497 bool useCoverageAA,
498 const SkRect& circle,
499 const SkStrokeRec& stroke)
500 {
501 GrDrawState* drawState = target->drawState();
503 const SkMatrix& vm = drawState->getViewMatrix();
504 GrPoint center = GrPoint::Make(circle.centerX(), circle.centerY());
505 vm.mapPoints(¢er, 1);
506 SkScalar radius = vm.mapRadius(SkScalarHalf(circle.width()));
507 SkScalar strokeWidth = vm.mapRadius(stroke.getWidth());
509 GrDrawState::AutoViewMatrixRestore avmr;
510 if (!avmr.setIdentity(drawState)) {
511 return;
512 }
514 drawState->setVertexAttribs<gCircleVertexAttribs>(SK_ARRAY_COUNT(gCircleVertexAttribs));
515 SkASSERT(sizeof(CircleVertex) == drawState->getVertexSize());
517 GrDrawTarget::AutoReleaseGeometry geo(target, 4, 0);
518 if (!geo.succeeded()) {
519 GrPrintf("Failed to get space for vertices!\n");
520 return;
521 }
523 CircleVertex* verts = reinterpret_cast<CircleVertex*>(geo.vertices());
525 SkStrokeRec::Style style = stroke.getStyle();
526 bool isStroked = (SkStrokeRec::kStroke_Style == style || SkStrokeRec::kHairline_Style == style);
528 SkScalar innerRadius = 0.0f;
529 SkScalar outerRadius = radius;
530 SkScalar halfWidth = 0;
531 if (style != SkStrokeRec::kFill_Style) {
532 if (SkScalarNearlyZero(strokeWidth)) {
533 halfWidth = SK_ScalarHalf;
534 } else {
535 halfWidth = SkScalarHalf(strokeWidth);
536 }
538 outerRadius += halfWidth;
539 if (isStroked) {
540 innerRadius = radius - halfWidth;
541 }
542 }
544 GrEffectRef* effect = CircleEdgeEffect::Create(isStroked && innerRadius > 0);
545 static const int kCircleEdgeAttrIndex = 1;
546 drawState->addCoverageEffect(effect, kCircleEdgeAttrIndex)->unref();
548 // The radii are outset for two reasons. First, it allows the shader to simply perform
549 // clamp(distance-to-center - radius, 0, 1). Second, the outer radius is used to compute the
550 // verts of the bounding box that is rendered and the outset ensures the box will cover all
551 // pixels partially covered by the circle.
552 outerRadius += SK_ScalarHalf;
553 innerRadius -= SK_ScalarHalf;
555 SkRect bounds = SkRect::MakeLTRB(
556 center.fX - outerRadius,
557 center.fY - outerRadius,
558 center.fX + outerRadius,
559 center.fY + outerRadius
560 );
562 verts[0].fPos = SkPoint::Make(bounds.fLeft, bounds.fTop);
563 verts[0].fOffset = SkPoint::Make(-outerRadius, -outerRadius);
564 verts[0].fOuterRadius = outerRadius;
565 verts[0].fInnerRadius = innerRadius;
567 verts[1].fPos = SkPoint::Make(bounds.fRight, bounds.fTop);
568 verts[1].fOffset = SkPoint::Make(outerRadius, -outerRadius);
569 verts[1].fOuterRadius = outerRadius;
570 verts[1].fInnerRadius = innerRadius;
572 verts[2].fPos = SkPoint::Make(bounds.fLeft, bounds.fBottom);
573 verts[2].fOffset = SkPoint::Make(-outerRadius, outerRadius);
574 verts[2].fOuterRadius = outerRadius;
575 verts[2].fInnerRadius = innerRadius;
577 verts[3].fPos = SkPoint::Make(bounds.fRight, bounds.fBottom);
578 verts[3].fOffset = SkPoint::Make(outerRadius, outerRadius);
579 verts[3].fOuterRadius = outerRadius;
580 verts[3].fInnerRadius = innerRadius;
582 target->drawNonIndexed(kTriangleStrip_GrPrimitiveType, 0, 4, &bounds);
583 }
585 ///////////////////////////////////////////////////////////////////////////////
587 // position + offset + 1/radii
588 extern const GrVertexAttrib gEllipseVertexAttribs[] = {
589 {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding},
590 {kVec2f_GrVertexAttribType, sizeof(GrPoint), kEffect_GrVertexAttribBinding},
591 {kVec4f_GrVertexAttribType, 2*sizeof(GrPoint), kEffect_GrVertexAttribBinding}
592 };
594 // position + offsets
595 extern const GrVertexAttrib gDIEllipseVertexAttribs[] = {
596 {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding},
597 {kVec2f_GrVertexAttribType, sizeof(GrPoint), kEffect_GrVertexAttribBinding},
598 {kVec2f_GrVertexAttribType, 2*sizeof(GrPoint), kEffect_GrVertexAttribBinding},
599 };
601 bool GrOvalRenderer::drawEllipse(GrDrawTarget* target,
602 bool useCoverageAA,
603 const SkRect& ellipse,
604 const SkStrokeRec& stroke)
605 {
606 GrDrawState* drawState = target->drawState();
607 #ifdef SK_DEBUG
608 {
609 // we should have checked for this previously
610 bool isAxisAlignedEllipse = drawState->getViewMatrix().rectStaysRect();
611 SkASSERT(useCoverageAA && isAxisAlignedEllipse);
612 }
613 #endif
615 // do any matrix crunching before we reset the draw state for device coords
616 const SkMatrix& vm = drawState->getViewMatrix();
617 GrPoint center = GrPoint::Make(ellipse.centerX(), ellipse.centerY());
618 vm.mapPoints(¢er, 1);
619 SkScalar ellipseXRadius = SkScalarHalf(ellipse.width());
620 SkScalar ellipseYRadius = SkScalarHalf(ellipse.height());
621 SkScalar xRadius = SkScalarAbs(vm[SkMatrix::kMScaleX]*ellipseXRadius +
622 vm[SkMatrix::kMSkewY]*ellipseYRadius);
623 SkScalar yRadius = SkScalarAbs(vm[SkMatrix::kMSkewX]*ellipseXRadius +
624 vm[SkMatrix::kMScaleY]*ellipseYRadius);
626 // do (potentially) anisotropic mapping of stroke
627 SkVector scaledStroke;
628 SkScalar strokeWidth = stroke.getWidth();
629 scaledStroke.fX = SkScalarAbs(strokeWidth*(vm[SkMatrix::kMScaleX] + vm[SkMatrix::kMSkewY]));
630 scaledStroke.fY = SkScalarAbs(strokeWidth*(vm[SkMatrix::kMSkewX] + vm[SkMatrix::kMScaleY]));
632 SkStrokeRec::Style style = stroke.getStyle();
633 bool isStroked = (SkStrokeRec::kStroke_Style == style || SkStrokeRec::kHairline_Style == style);
635 SkScalar innerXRadius = 0;
636 SkScalar innerYRadius = 0;
637 if (SkStrokeRec::kFill_Style != style) {
638 if (SkScalarNearlyZero(scaledStroke.length())) {
639 scaledStroke.set(SK_ScalarHalf, SK_ScalarHalf);
640 } else {
641 scaledStroke.scale(SK_ScalarHalf);
642 }
644 // we only handle thick strokes for near-circular ellipses
645 if (scaledStroke.length() > SK_ScalarHalf &&
646 (SK_ScalarHalf*xRadius > yRadius || SK_ScalarHalf*yRadius > xRadius)) {
647 return false;
648 }
650 // we don't handle it if curvature of the stroke is less than curvature of the ellipse
651 if (scaledStroke.fX*(yRadius*yRadius) < (scaledStroke.fY*scaledStroke.fY)*xRadius ||
652 scaledStroke.fY*(xRadius*xRadius) < (scaledStroke.fX*scaledStroke.fX)*yRadius) {
653 return false;
654 }
656 // this is legit only if scale & translation (which should be the case at the moment)
657 if (isStroked) {
658 innerXRadius = xRadius - scaledStroke.fX;
659 innerYRadius = yRadius - scaledStroke.fY;
660 }
662 xRadius += scaledStroke.fX;
663 yRadius += scaledStroke.fY;
664 }
666 GrDrawState::AutoViewMatrixRestore avmr;
667 if (!avmr.setIdentity(drawState)) {
668 return false;
669 }
671 drawState->setVertexAttribs<gEllipseVertexAttribs>(SK_ARRAY_COUNT(gEllipseVertexAttribs));
672 SkASSERT(sizeof(EllipseVertex) == drawState->getVertexSize());
674 GrDrawTarget::AutoReleaseGeometry geo(target, 4, 0);
675 if (!geo.succeeded()) {
676 GrPrintf("Failed to get space for vertices!\n");
677 return false;
678 }
680 EllipseVertex* verts = reinterpret_cast<EllipseVertex*>(geo.vertices());
682 GrEffectRef* effect = EllipseEdgeEffect::Create(isStroked &&
683 innerXRadius > 0 && innerYRadius > 0);
685 static const int kEllipseCenterAttrIndex = 1;
686 static const int kEllipseEdgeAttrIndex = 2;
687 drawState->addCoverageEffect(effect, kEllipseCenterAttrIndex, kEllipseEdgeAttrIndex)->unref();
689 // Compute the reciprocals of the radii here to save time in the shader
690 SkScalar xRadRecip = SkScalarInvert(xRadius);
691 SkScalar yRadRecip = SkScalarInvert(yRadius);
692 SkScalar xInnerRadRecip = SkScalarInvert(innerXRadius);
693 SkScalar yInnerRadRecip = SkScalarInvert(innerYRadius);
695 // We've extended the outer x radius out half a pixel to antialias.
696 // This will also expand the rect so all the pixels will be captured.
697 // TODO: Consider if we should use sqrt(2)/2 instead
698 xRadius += SK_ScalarHalf;
699 yRadius += SK_ScalarHalf;
701 SkRect bounds = SkRect::MakeLTRB(
702 center.fX - xRadius,
703 center.fY - yRadius,
704 center.fX + xRadius,
705 center.fY + yRadius
706 );
708 verts[0].fPos = SkPoint::Make(bounds.fLeft, bounds.fTop);
709 verts[0].fOffset = SkPoint::Make(-xRadius, -yRadius);
710 verts[0].fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip);
711 verts[0].fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip);
713 verts[1].fPos = SkPoint::Make(bounds.fRight, bounds.fTop);
714 verts[1].fOffset = SkPoint::Make(xRadius, -yRadius);
715 verts[1].fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip);
716 verts[1].fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip);
718 verts[2].fPos = SkPoint::Make(bounds.fLeft, bounds.fBottom);
719 verts[2].fOffset = SkPoint::Make(-xRadius, yRadius);
720 verts[2].fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip);
721 verts[2].fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip);
723 verts[3].fPos = SkPoint::Make(bounds.fRight, bounds.fBottom);
724 verts[3].fOffset = SkPoint::Make(xRadius, yRadius);
725 verts[3].fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip);
726 verts[3].fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip);
728 target->drawNonIndexed(kTriangleStrip_GrPrimitiveType, 0, 4, &bounds);
730 return true;
731 }
733 bool GrOvalRenderer::drawDIEllipse(GrDrawTarget* target,
734 bool useCoverageAA,
735 const SkRect& ellipse,
736 const SkStrokeRec& stroke)
737 {
738 GrDrawState* drawState = target->drawState();
739 const SkMatrix& vm = drawState->getViewMatrix();
741 GrPoint center = GrPoint::Make(ellipse.centerX(), ellipse.centerY());
742 SkScalar xRadius = SkScalarHalf(ellipse.width());
743 SkScalar yRadius = SkScalarHalf(ellipse.height());
745 SkStrokeRec::Style style = stroke.getStyle();
746 DIEllipseEdgeEffect::Mode mode = (SkStrokeRec::kStroke_Style == style) ?
747 DIEllipseEdgeEffect::kStroke :
748 (SkStrokeRec::kHairline_Style == style) ?
749 DIEllipseEdgeEffect::kHairline : DIEllipseEdgeEffect::kFill;
751 SkScalar innerXRadius = 0;
752 SkScalar innerYRadius = 0;
753 if (SkStrokeRec::kFill_Style != style && SkStrokeRec::kHairline_Style != style) {
754 SkScalar strokeWidth = stroke.getWidth();
756 if (SkScalarNearlyZero(strokeWidth)) {
757 strokeWidth = SK_ScalarHalf;
758 } else {
759 strokeWidth *= SK_ScalarHalf;
760 }
762 // we only handle thick strokes for near-circular ellipses
763 if (strokeWidth > SK_ScalarHalf &&
764 (SK_ScalarHalf*xRadius > yRadius || SK_ScalarHalf*yRadius > xRadius)) {
765 return false;
766 }
768 // we don't handle it if curvature of the stroke is less than curvature of the ellipse
769 if (strokeWidth*(yRadius*yRadius) < (strokeWidth*strokeWidth)*xRadius ||
770 strokeWidth*(xRadius*xRadius) < (strokeWidth*strokeWidth)*yRadius) {
771 return false;
772 }
774 // set inner radius (if needed)
775 if (SkStrokeRec::kStroke_Style == style) {
776 innerXRadius = xRadius - strokeWidth;
777 innerYRadius = yRadius - strokeWidth;
778 }
780 xRadius += strokeWidth;
781 yRadius += strokeWidth;
782 }
783 if (DIEllipseEdgeEffect::kStroke == mode) {
784 mode = (innerXRadius > 0 && innerYRadius > 0) ? DIEllipseEdgeEffect::kStroke :
785 DIEllipseEdgeEffect::kFill;
786 }
787 SkScalar innerRatioX = SkScalarDiv(xRadius, innerXRadius);
788 SkScalar innerRatioY = SkScalarDiv(yRadius, innerYRadius);
790 drawState->setVertexAttribs<gDIEllipseVertexAttribs>(SK_ARRAY_COUNT(gDIEllipseVertexAttribs));
791 SkASSERT(sizeof(DIEllipseVertex) == drawState->getVertexSize());
793 GrDrawTarget::AutoReleaseGeometry geo(target, 4, 0);
794 if (!geo.succeeded()) {
795 GrPrintf("Failed to get space for vertices!\n");
796 return false;
797 }
799 DIEllipseVertex* verts = reinterpret_cast<DIEllipseVertex*>(geo.vertices());
801 GrEffectRef* effect = DIEllipseEdgeEffect::Create(mode);
803 static const int kEllipseOuterOffsetAttrIndex = 1;
804 static const int kEllipseInnerOffsetAttrIndex = 2;
805 drawState->addCoverageEffect(effect, kEllipseOuterOffsetAttrIndex,
806 kEllipseInnerOffsetAttrIndex)->unref();
808 // This expands the outer rect so that after CTM we end up with a half-pixel border
809 SkScalar a = vm[SkMatrix::kMScaleX];
810 SkScalar b = vm[SkMatrix::kMSkewX];
811 SkScalar c = vm[SkMatrix::kMSkewY];
812 SkScalar d = vm[SkMatrix::kMScaleY];
813 SkScalar geoDx = SkScalarDiv(SK_ScalarHalf, SkScalarSqrt(a*a + c*c));
814 SkScalar geoDy = SkScalarDiv(SK_ScalarHalf, SkScalarSqrt(b*b + d*d));
815 // This adjusts the "radius" to include the half-pixel border
816 SkScalar offsetDx = SkScalarDiv(geoDx, xRadius);
817 SkScalar offsetDy = SkScalarDiv(geoDy, yRadius);
819 SkRect bounds = SkRect::MakeLTRB(
820 center.fX - xRadius - geoDx,
821 center.fY - yRadius - geoDy,
822 center.fX + xRadius + geoDx,
823 center.fY + yRadius + geoDy
824 );
826 verts[0].fPos = SkPoint::Make(bounds.fLeft, bounds.fTop);
827 verts[0].fOuterOffset = SkPoint::Make(-1.0f - offsetDx, -1.0f - offsetDy);
828 verts[0].fInnerOffset = SkPoint::Make(-innerRatioX - offsetDx, -innerRatioY - offsetDy);
830 verts[1].fPos = SkPoint::Make(bounds.fRight, bounds.fTop);
831 verts[1].fOuterOffset = SkPoint::Make(1.0f + offsetDx, -1.0f - offsetDy);
832 verts[1].fInnerOffset = SkPoint::Make(innerRatioX + offsetDx, -innerRatioY - offsetDy);
834 verts[2].fPos = SkPoint::Make(bounds.fLeft, bounds.fBottom);
835 verts[2].fOuterOffset = SkPoint::Make(-1.0f - offsetDx, 1.0f + offsetDy);
836 verts[2].fInnerOffset = SkPoint::Make(-innerRatioX - offsetDx, innerRatioY + offsetDy);
838 verts[3].fPos = SkPoint::Make(bounds.fRight, bounds.fBottom);
839 verts[3].fOuterOffset = SkPoint::Make(1.0f + offsetDx, 1.0f + offsetDy);
840 verts[3].fInnerOffset = SkPoint::Make(innerRatioX + offsetDx, innerRatioY + offsetDy);
842 target->drawNonIndexed(kTriangleStrip_GrPrimitiveType, 0, 4, &bounds);
844 return true;
845 }
847 ///////////////////////////////////////////////////////////////////////////////
849 static const uint16_t gRRectIndices[] = {
850 // corners
851 0, 1, 5, 0, 5, 4,
852 2, 3, 7, 2, 7, 6,
853 8, 9, 13, 8, 13, 12,
854 10, 11, 15, 10, 15, 14,
856 // edges
857 1, 2, 6, 1, 6, 5,
858 4, 5, 9, 4, 9, 8,
859 6, 7, 11, 6, 11, 10,
860 9, 10, 14, 9, 14, 13,
862 // center
863 // we place this at the end so that we can ignore these indices when rendering stroke-only
864 5, 6, 10, 5, 10, 9
865 };
868 GrIndexBuffer* GrOvalRenderer::rRectIndexBuffer(GrGpu* gpu) {
869 if (NULL == fRRectIndexBuffer) {
870 fRRectIndexBuffer =
871 gpu->createIndexBuffer(sizeof(gRRectIndices), false);
872 if (NULL != fRRectIndexBuffer) {
873 #ifdef SK_DEBUG
874 bool updated =
875 #endif
876 fRRectIndexBuffer->updateData(gRRectIndices,
877 sizeof(gRRectIndices));
878 GR_DEBUGASSERT(updated);
879 }
880 }
881 return fRRectIndexBuffer;
882 }
884 bool GrOvalRenderer::drawSimpleRRect(GrDrawTarget* target, GrContext* context, bool useAA,
885 const SkRRect& rrect, const SkStrokeRec& stroke)
886 {
887 bool useCoverageAA = useAA &&
888 !target->getDrawState().getRenderTarget()->isMultisampled() &&
889 !target->shouldDisableCoverageAAForBlend();
891 // only anti-aliased rrects for now
892 if (!useCoverageAA) {
893 return false;
894 }
896 const SkMatrix& vm = context->getMatrix();
897 #ifdef SK_DEBUG
898 {
899 // we should have checked for this previously
900 SkASSERT(useCoverageAA && vm.rectStaysRect() && rrect.isSimple());
901 }
902 #endif
904 // do any matrix crunching before we reset the draw state for device coords
905 const SkRect& rrectBounds = rrect.getBounds();
906 SkRect bounds;
907 vm.mapRect(&bounds, rrectBounds);
909 SkVector radii = rrect.getSimpleRadii();
910 SkScalar xRadius = SkScalarAbs(vm[SkMatrix::kMScaleX]*radii.fX +
911 vm[SkMatrix::kMSkewY]*radii.fY);
912 SkScalar yRadius = SkScalarAbs(vm[SkMatrix::kMSkewX]*radii.fX +
913 vm[SkMatrix::kMScaleY]*radii.fY);
915 // if hairline stroke is greater than radius, we don't handle that right now
916 SkStrokeRec::Style style = stroke.getStyle();
917 if (SkStrokeRec::kHairline_Style == style &&
918 (SK_ScalarHalf > xRadius || SK_ScalarHalf > yRadius)) {
919 return false;
920 }
922 // do (potentially) anisotropic mapping of stroke
923 SkVector scaledStroke;
924 SkScalar strokeWidth = stroke.getWidth();
925 scaledStroke.fX = SkScalarAbs(strokeWidth*(vm[SkMatrix::kMScaleX] + vm[SkMatrix::kMSkewY]));
926 scaledStroke.fY = SkScalarAbs(strokeWidth*(vm[SkMatrix::kMSkewX] + vm[SkMatrix::kMScaleY]));
928 // if half of strokewidth is greater than radius, we don't handle that right now
929 if (SK_ScalarHalf*scaledStroke.fX > xRadius || SK_ScalarHalf*scaledStroke.fY > yRadius) {
930 return false;
931 }
933 // reset to device coordinates
934 GrDrawState* drawState = target->drawState();
935 GrDrawState::AutoViewMatrixRestore avmr;
936 if (!avmr.setIdentity(drawState)) {
937 return false;
938 }
940 bool isStroked = (SkStrokeRec::kStroke_Style == style || SkStrokeRec::kHairline_Style == style);
942 GrIndexBuffer* indexBuffer = this->rRectIndexBuffer(context->getGpu());
943 if (NULL == indexBuffer) {
944 GrPrintf("Failed to create index buffer!\n");
945 return false;
946 }
948 // if the corners are circles, use the circle renderer
949 if ((!isStroked || scaledStroke.fX == scaledStroke.fY) && xRadius == yRadius) {
950 drawState->setVertexAttribs<gCircleVertexAttribs>(SK_ARRAY_COUNT(gCircleVertexAttribs));
951 SkASSERT(sizeof(CircleVertex) == drawState->getVertexSize());
953 GrDrawTarget::AutoReleaseGeometry geo(target, 16, 0);
954 if (!geo.succeeded()) {
955 GrPrintf("Failed to get space for vertices!\n");
956 return false;
957 }
958 CircleVertex* verts = reinterpret_cast<CircleVertex*>(geo.vertices());
960 SkScalar innerRadius = 0.0f;
961 SkScalar outerRadius = xRadius;
962 SkScalar halfWidth = 0;
963 if (style != SkStrokeRec::kFill_Style) {
964 if (SkScalarNearlyZero(scaledStroke.fX)) {
965 halfWidth = SK_ScalarHalf;
966 } else {
967 halfWidth = SkScalarHalf(scaledStroke.fX);
968 }
970 if (isStroked) {
971 innerRadius = xRadius - halfWidth;
972 }
973 outerRadius += halfWidth;
974 bounds.outset(halfWidth, halfWidth);
975 }
977 isStroked = (isStroked && innerRadius >= 0);
979 GrEffectRef* effect = CircleEdgeEffect::Create(isStroked);
980 static const int kCircleEdgeAttrIndex = 1;
981 drawState->addCoverageEffect(effect, kCircleEdgeAttrIndex)->unref();
983 // The radii are outset for two reasons. First, it allows the shader to simply perform
984 // clamp(distance-to-center - radius, 0, 1). Second, the outer radius is used to compute the
985 // verts of the bounding box that is rendered and the outset ensures the box will cover all
986 // pixels partially covered by the circle.
987 outerRadius += SK_ScalarHalf;
988 innerRadius -= SK_ScalarHalf;
990 // Expand the rect so all the pixels will be captured.
991 bounds.outset(SK_ScalarHalf, SK_ScalarHalf);
993 SkScalar yCoords[4] = {
994 bounds.fTop,
995 bounds.fTop + outerRadius,
996 bounds.fBottom - outerRadius,
997 bounds.fBottom
998 };
999 SkScalar yOuterRadii[4] = {
1000 -outerRadius,
1001 0,
1002 0,
1003 outerRadius
1004 };
1005 for (int i = 0; i < 4; ++i) {
1006 verts->fPos = SkPoint::Make(bounds.fLeft, yCoords[i]);
1007 verts->fOffset = SkPoint::Make(-outerRadius, yOuterRadii[i]);
1008 verts->fOuterRadius = outerRadius;
1009 verts->fInnerRadius = innerRadius;
1010 verts++;
1012 verts->fPos = SkPoint::Make(bounds.fLeft + outerRadius, yCoords[i]);
1013 verts->fOffset = SkPoint::Make(0, yOuterRadii[i]);
1014 verts->fOuterRadius = outerRadius;
1015 verts->fInnerRadius = innerRadius;
1016 verts++;
1018 verts->fPos = SkPoint::Make(bounds.fRight - outerRadius, yCoords[i]);
1019 verts->fOffset = SkPoint::Make(0, yOuterRadii[i]);
1020 verts->fOuterRadius = outerRadius;
1021 verts->fInnerRadius = innerRadius;
1022 verts++;
1024 verts->fPos = SkPoint::Make(bounds.fRight, yCoords[i]);
1025 verts->fOffset = SkPoint::Make(outerRadius, yOuterRadii[i]);
1026 verts->fOuterRadius = outerRadius;
1027 verts->fInnerRadius = innerRadius;
1028 verts++;
1029 }
1031 // drop out the middle quad if we're stroked
1032 int indexCnt = isStroked ? GR_ARRAY_COUNT(gRRectIndices)-6 : GR_ARRAY_COUNT(gRRectIndices);
1033 target->setIndexSourceToBuffer(indexBuffer);
1034 target->drawIndexed(kTriangles_GrPrimitiveType, 0, 0, 16, indexCnt, &bounds);
1036 // otherwise we use the ellipse renderer
1037 } else {
1038 drawState->setVertexAttribs<gEllipseVertexAttribs>(SK_ARRAY_COUNT(gEllipseVertexAttribs));
1039 SkASSERT(sizeof(EllipseVertex) == drawState->getVertexSize());
1041 SkScalar innerXRadius = 0.0f;
1042 SkScalar innerYRadius = 0.0f;
1043 if (SkStrokeRec::kFill_Style != style) {
1044 if (SkScalarNearlyZero(scaledStroke.length())) {
1045 scaledStroke.set(SK_ScalarHalf, SK_ScalarHalf);
1046 } else {
1047 scaledStroke.scale(SK_ScalarHalf);
1048 }
1050 // we only handle thick strokes for near-circular ellipses
1051 if (scaledStroke.length() > SK_ScalarHalf &&
1052 (SK_ScalarHalf*xRadius > yRadius || SK_ScalarHalf*yRadius > xRadius)) {
1053 return false;
1054 }
1056 // we don't handle it if curvature of the stroke is less than curvature of the ellipse
1057 if (scaledStroke.fX*(yRadius*yRadius) < (scaledStroke.fY*scaledStroke.fY)*xRadius ||
1058 scaledStroke.fY*(xRadius*xRadius) < (scaledStroke.fX*scaledStroke.fX)*yRadius) {
1059 return false;
1060 }
1062 // this is legit only if scale & translation (which should be the case at the moment)
1063 if (isStroked) {
1064 innerXRadius = xRadius - scaledStroke.fX;
1065 innerYRadius = yRadius - scaledStroke.fY;
1066 }
1068 xRadius += scaledStroke.fX;
1069 yRadius += scaledStroke.fY;
1070 bounds.outset(scaledStroke.fX, scaledStroke.fY);
1071 }
1073 isStroked = (isStroked && innerXRadius >= 0 && innerYRadius >= 0);
1075 GrDrawTarget::AutoReleaseGeometry geo(target, 16, 0);
1076 if (!geo.succeeded()) {
1077 GrPrintf("Failed to get space for vertices!\n");
1078 return false;
1079 }
1080 EllipseVertex* verts = reinterpret_cast<EllipseVertex*>(geo.vertices());
1082 GrEffectRef* effect = EllipseEdgeEffect::Create(isStroked);
1083 static const int kEllipseOffsetAttrIndex = 1;
1084 static const int kEllipseRadiiAttrIndex = 2;
1085 drawState->addCoverageEffect(effect,
1086 kEllipseOffsetAttrIndex, kEllipseRadiiAttrIndex)->unref();
1088 // Compute the reciprocals of the radii here to save time in the shader
1089 SkScalar xRadRecip = SkScalarInvert(xRadius);
1090 SkScalar yRadRecip = SkScalarInvert(yRadius);
1091 SkScalar xInnerRadRecip = SkScalarInvert(innerXRadius);
1092 SkScalar yInnerRadRecip = SkScalarInvert(innerYRadius);
1094 // Extend the radii out half a pixel to antialias.
1095 SkScalar xOuterRadius = xRadius + SK_ScalarHalf;
1096 SkScalar yOuterRadius = yRadius + SK_ScalarHalf;
1098 // Expand the rect so all the pixels will be captured.
1099 bounds.outset(SK_ScalarHalf, SK_ScalarHalf);
1101 SkScalar yCoords[4] = {
1102 bounds.fTop,
1103 bounds.fTop + yOuterRadius,
1104 bounds.fBottom - yOuterRadius,
1105 bounds.fBottom
1106 };
1107 SkScalar yOuterOffsets[4] = {
1108 yOuterRadius,
1109 SK_ScalarNearlyZero, // we're using inversesqrt() in the shader, so can't be exactly 0
1110 SK_ScalarNearlyZero,
1111 yOuterRadius
1112 };
1114 for (int i = 0; i < 4; ++i) {
1115 verts->fPos = SkPoint::Make(bounds.fLeft, yCoords[i]);
1116 verts->fOffset = SkPoint::Make(xOuterRadius, yOuterOffsets[i]);
1117 verts->fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip);
1118 verts->fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip);
1119 verts++;
1121 verts->fPos = SkPoint::Make(bounds.fLeft + xOuterRadius, yCoords[i]);
1122 verts->fOffset = SkPoint::Make(SK_ScalarNearlyZero, yOuterOffsets[i]);
1123 verts->fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip);
1124 verts->fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip);
1125 verts++;
1127 verts->fPos = SkPoint::Make(bounds.fRight - xOuterRadius, yCoords[i]);
1128 verts->fOffset = SkPoint::Make(SK_ScalarNearlyZero, yOuterOffsets[i]);
1129 verts->fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip);
1130 verts->fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip);
1131 verts++;
1133 verts->fPos = SkPoint::Make(bounds.fRight, yCoords[i]);
1134 verts->fOffset = SkPoint::Make(xOuterRadius, yOuterOffsets[i]);
1135 verts->fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip);
1136 verts->fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip);
1137 verts++;
1138 }
1140 // drop out the middle quad if we're stroked
1141 int indexCnt = isStroked ? GR_ARRAY_COUNT(gRRectIndices)-6 : GR_ARRAY_COUNT(gRRectIndices);
1142 target->setIndexSourceToBuffer(indexBuffer);
1143 target->drawIndexed(kTriangles_GrPrimitiveType, 0, 0, 16, indexCnt, &bounds);
1144 }
1146 return true;
1147 }
