commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 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 | */ |
| 7 | |
| 8 | #include "GrOvalRenderer.h" |
| 9 | |
commit-bot@chromium.org | 90c240a | 2013-04-02 17:57:21 +0000 | [diff] [blame^] | 10 | #include "GrEffect.h" |
| 11 | #include "gl/GrGLEffect.h" |
| 12 | #include "gl/GrGLSL.h" |
| 13 | #include "GrTBackendEffectFactory.h" |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 14 | |
| 15 | #include "GrDrawState.h" |
| 16 | #include "GrDrawTarget.h" |
| 17 | #include "SkStrokeRec.h" |
| 18 | |
| 19 | SK_DEFINE_INST_COUNT(GrOvalRenderer) |
| 20 | |
| 21 | namespace { |
| 22 | |
| 23 | struct CircleVertex { |
| 24 | GrPoint fPos; |
| 25 | GrPoint fCenter; |
| 26 | SkScalar fOuterRadius; |
| 27 | SkScalar fInnerRadius; |
| 28 | }; |
| 29 | |
| 30 | struct EllipseVertex { |
| 31 | GrPoint fPos; |
| 32 | GrPoint fCenter; |
| 33 | SkScalar fOuterXRadius; |
| 34 | SkScalar fOuterXYRatio; |
| 35 | SkScalar fInnerXRadius; |
| 36 | SkScalar fInnerXYRatio; |
| 37 | }; |
| 38 | |
| 39 | inline bool circle_stays_circle(const SkMatrix& m) { |
| 40 | return m.isSimilarity(); |
| 41 | } |
| 42 | |
| 43 | } |
| 44 | |
commit-bot@chromium.org | 90c240a | 2013-04-02 17:57:21 +0000 | [diff] [blame^] | 45 | /////////////////////////////////////////////////////////////////////////////// |
| 46 | |
| 47 | /** |
| 48 | * The output of this effect is a modulation of the input color and coverage for a circle, |
| 49 | * specified as center_x, center_y, x_radius, inner radius and outer radius in window space |
| 50 | * (y-down). |
| 51 | */ |
| 52 | |
| 53 | class CircleEdgeEffect : public GrEffect { |
| 54 | public: |
| 55 | static GrEffectRef* Create(bool stroke) { |
| 56 | // we go through this so we only have one copy of each effect (stroked/filled) |
| 57 | static SkAutoTUnref<GrEffectRef> gCircleStrokeEdgeEffectRef( |
| 58 | CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(CircleEdgeEffect, (true))))); |
| 59 | static SkAutoTUnref<GrEffectRef> gCircleFillEdgeEffectRef( |
| 60 | CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(CircleEdgeEffect, (false))))); |
| 61 | |
| 62 | if (stroke) { |
| 63 | gCircleStrokeEdgeEffectRef.get()->ref(); |
| 64 | return gCircleStrokeEdgeEffectRef; |
| 65 | } else { |
| 66 | gCircleFillEdgeEffectRef.get()->ref(); |
| 67 | return gCircleFillEdgeEffectRef; |
| 68 | } |
| 69 | } |
| 70 | |
| 71 | virtual void getConstantColorComponents(GrColor* color, |
| 72 | uint32_t* validFlags) const SK_OVERRIDE { |
| 73 | *validFlags = 0; |
| 74 | } |
| 75 | |
| 76 | virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE { |
| 77 | return GrTBackendEffectFactory<CircleEdgeEffect>::getInstance(); |
| 78 | } |
| 79 | |
| 80 | virtual ~CircleEdgeEffect() {} |
| 81 | |
| 82 | static const char* Name() { return "CircleEdge"; } |
| 83 | |
| 84 | inline bool isStroked() const { return fStroke; } |
| 85 | |
| 86 | class GLEffect : public GrGLEffect { |
| 87 | public: |
| 88 | GLEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&) |
| 89 | : INHERITED (factory) {} |
| 90 | |
| 91 | virtual void emitCode(GrGLShaderBuilder* builder, |
| 92 | const GrDrawEffect& drawEffect, |
| 93 | EffectKey key, |
| 94 | const char* outputColor, |
| 95 | const char* inputColor, |
| 96 | const TextureSamplerArray& samplers) SK_OVERRIDE { |
| 97 | const CircleEdgeEffect& circleEffect = drawEffect.castEffect<CircleEdgeEffect>(); |
| 98 | const char *vsName, *fsName; |
| 99 | builder->addVarying(kVec4f_GrSLType, "CircleEdge", &vsName, &fsName); |
| 100 | |
| 101 | const SkString* attrName = |
| 102 | builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[0]); |
| 103 | builder->vsCodeAppendf("\t%s = %s;\n", vsName, attrName->c_str()); |
| 104 | |
| 105 | builder->fsCodeAppendf("\tfloat d = distance(%s.xy, %s.xy);\n", |
| 106 | builder->fragmentPosition(), fsName); |
| 107 | builder->fsCodeAppendf("\tfloat edgeAlpha = clamp(%s.z - d, 0.0, 1.0);\n", fsName); |
| 108 | if (circleEffect.isStroked()) { |
| 109 | builder->fsCodeAppendf("\tfloat innerAlpha = clamp(d - %s.w, 0.0, 1.0);\n", fsName); |
| 110 | builder->fsCodeAppend("\tedgeAlpha *= innerAlpha;\n"); |
| 111 | } |
| 112 | SkString modulate; |
| 113 | GrGLSLModulate4f(&modulate, inputColor, "edgeAlpha"); |
| 114 | builder->fsCodeAppendf("\t%s = %s;\n", outputColor, modulate.c_str()); |
| 115 | } |
| 116 | |
| 117 | static inline EffectKey GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) { |
| 118 | const CircleEdgeEffect& circleEffect = drawEffect.castEffect<CircleEdgeEffect>(); |
| 119 | |
| 120 | return circleEffect.isStroked() ? 0x1 : 0x0; |
| 121 | } |
| 122 | |
| 123 | virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE {} |
| 124 | |
| 125 | private: |
| 126 | typedef GrGLEffect INHERITED; |
| 127 | }; |
| 128 | |
| 129 | |
| 130 | private: |
| 131 | CircleEdgeEffect(bool stroke) : GrEffect() { |
| 132 | this->addVertexAttrib(kVec4f_GrSLType); |
| 133 | fStroke = stroke; |
| 134 | } |
| 135 | |
| 136 | virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE { |
| 137 | const CircleEdgeEffect& cee = CastEffect<CircleEdgeEffect>(other); |
| 138 | return cee.fStroke == fStroke; |
| 139 | } |
| 140 | |
| 141 | bool fStroke; |
| 142 | |
| 143 | GR_DECLARE_EFFECT_TEST; |
| 144 | |
| 145 | typedef GrEffect INHERITED; |
| 146 | }; |
| 147 | |
| 148 | GR_DEFINE_EFFECT_TEST(CircleEdgeEffect); |
| 149 | |
| 150 | GrEffectRef* CircleEdgeEffect::TestCreate(SkMWCRandom* random, |
| 151 | GrContext* context, |
| 152 | const GrDrawTargetCaps&, |
| 153 | GrTexture* textures[]) { |
| 154 | return CircleEdgeEffect::Create(random->nextBool()); |
| 155 | } |
| 156 | |
| 157 | /////////////////////////////////////////////////////////////////////////////// |
| 158 | |
| 159 | /** |
| 160 | * The output of this effect is a modulation of the input color and coverage for an axis-aligned |
| 161 | * ellipse, specified as center_x, center_y, x_radius, x_radius/y_radius in window space (y-down). |
| 162 | */ |
| 163 | |
| 164 | class EllipseEdgeEffect : public GrEffect { |
| 165 | public: |
| 166 | static GrEffectRef* Create(bool stroke) { |
| 167 | // we go through this so we only have one copy of each effect (stroked/filled) |
| 168 | static SkAutoTUnref<GrEffectRef> gEllipseStrokeEdgeEffectRef( |
| 169 | CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(EllipseEdgeEffect, (true))))); |
| 170 | static SkAutoTUnref<GrEffectRef> gEllipseFillEdgeEffectRef( |
| 171 | CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(EllipseEdgeEffect, (false))))); |
| 172 | |
| 173 | if (stroke) { |
| 174 | gEllipseStrokeEdgeEffectRef.get()->ref(); |
| 175 | return gEllipseStrokeEdgeEffectRef; |
| 176 | } else { |
| 177 | gEllipseFillEdgeEffectRef.get()->ref(); |
| 178 | return gEllipseFillEdgeEffectRef; |
| 179 | } |
| 180 | } |
| 181 | |
| 182 | virtual void getConstantColorComponents(GrColor* color, |
| 183 | uint32_t* validFlags) const SK_OVERRIDE { |
| 184 | *validFlags = 0; |
| 185 | } |
| 186 | |
| 187 | virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE { |
| 188 | return GrTBackendEffectFactory<EllipseEdgeEffect>::getInstance(); |
| 189 | } |
| 190 | |
| 191 | virtual ~EllipseEdgeEffect() {} |
| 192 | |
| 193 | static const char* Name() { return "EllipseEdge"; } |
| 194 | |
| 195 | inline bool isStroked() const { return fStroke; } |
| 196 | |
| 197 | class GLEffect : public GrGLEffect { |
| 198 | public: |
| 199 | GLEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&) |
| 200 | : INHERITED (factory) {} |
| 201 | |
| 202 | virtual void emitCode(GrGLShaderBuilder* builder, |
| 203 | const GrDrawEffect& drawEffect, |
| 204 | EffectKey key, |
| 205 | const char* outputColor, |
| 206 | const char* inputColor, |
| 207 | const TextureSamplerArray& samplers) SK_OVERRIDE { |
| 208 | const EllipseEdgeEffect& ellipseEffect = drawEffect.castEffect<EllipseEdgeEffect>(); |
| 209 | |
| 210 | const char *vsCenterName, *fsCenterName; |
| 211 | const char *vsEdgeName, *fsEdgeName; |
| 212 | |
| 213 | builder->addVarying(kVec2f_GrSLType, "EllipseCenter", &vsCenterName, &fsCenterName); |
| 214 | const SkString* attr0Name = |
| 215 | builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[0]); |
| 216 | builder->vsCodeAppendf("\t%s = %s;\n", vsCenterName, attr0Name->c_str()); |
| 217 | |
| 218 | builder->addVarying(kVec4f_GrSLType, "EllipseEdge", &vsEdgeName, &fsEdgeName); |
| 219 | const SkString* attr1Name = |
| 220 | builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[1]); |
| 221 | builder->vsCodeAppendf("\t%s = %s;\n", vsEdgeName, attr1Name->c_str()); |
| 222 | |
| 223 | // translate to origin |
| 224 | builder->fsCodeAppendf("\tvec2 outerOffset = (%s.xy - %s.xy);\n", |
| 225 | builder->fragmentPosition(), fsCenterName); |
| 226 | builder->fsCodeAppend("\tvec2 innerOffset = outerOffset;\n"); |
| 227 | // scale y by xRadius/yRadius |
| 228 | builder->fsCodeAppendf("\touterOffset.y *= %s.y;\n", fsEdgeName); |
| 229 | builder->fsCodeAppend("\tfloat dOuter = length(outerOffset);\n"); |
| 230 | // compare outer lengths against xOuterRadius |
| 231 | builder->fsCodeAppendf("\tfloat edgeAlpha = clamp(%s.x-dOuter, 0.0, 1.0);\n", |
| 232 | fsEdgeName); |
| 233 | |
| 234 | if (ellipseEffect.isStroked()) { |
| 235 | builder->fsCodeAppendf("\tinnerOffset.y *= %s.w;\n", fsEdgeName); |
| 236 | builder->fsCodeAppend("\tfloat dInner = length(innerOffset);\n"); |
| 237 | |
| 238 | // compare inner lengths against xInnerRadius |
| 239 | builder->fsCodeAppendf("\tfloat innerAlpha = clamp(dInner-%s.z, 0.0, 1.0);\n", |
| 240 | fsEdgeName); |
| 241 | builder->fsCodeAppend("\tedgeAlpha *= innerAlpha;\n"); |
| 242 | } |
| 243 | |
| 244 | SkString modulate; |
| 245 | GrGLSLModulate4f(&modulate, inputColor, "edgeAlpha"); |
| 246 | builder->fsCodeAppendf("\t%s = %s;\n", outputColor, modulate.c_str()); |
| 247 | } |
| 248 | |
| 249 | static inline EffectKey GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) { |
| 250 | const EllipseEdgeEffect& ellipseEffect = drawEffect.castEffect<EllipseEdgeEffect>(); |
| 251 | |
| 252 | return ellipseEffect.isStroked() ? 0x1 : 0x0; |
| 253 | } |
| 254 | |
| 255 | virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE { |
| 256 | } |
| 257 | |
| 258 | private: |
| 259 | typedef GrGLEffect INHERITED; |
| 260 | }; |
| 261 | |
| 262 | private: |
| 263 | EllipseEdgeEffect(bool stroke) : GrEffect() { |
| 264 | this->addVertexAttrib(kVec2f_GrSLType); |
| 265 | this->addVertexAttrib(kVec4f_GrSLType); |
| 266 | fStroke = stroke; |
| 267 | } |
| 268 | |
| 269 | virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE { |
| 270 | const EllipseEdgeEffect& eee = CastEffect<EllipseEdgeEffect>(other); |
| 271 | return eee.fStroke == fStroke; |
| 272 | } |
| 273 | |
| 274 | bool fStroke; |
| 275 | |
| 276 | GR_DECLARE_EFFECT_TEST; |
| 277 | |
| 278 | typedef GrEffect INHERITED; |
| 279 | }; |
| 280 | |
| 281 | GR_DEFINE_EFFECT_TEST(EllipseEdgeEffect); |
| 282 | |
| 283 | GrEffectRef* EllipseEdgeEffect::TestCreate(SkMWCRandom* random, |
| 284 | GrContext* context, |
| 285 | const GrDrawTargetCaps&, |
| 286 | GrTexture* textures[]) { |
| 287 | return EllipseEdgeEffect::Create(random->nextBool()); |
| 288 | } |
| 289 | |
| 290 | /////////////////////////////////////////////////////////////////////////////// |
| 291 | |
skia.committer@gmail.com | 7e32851 | 2013-03-23 07:01:28 +0000 | [diff] [blame] | 292 | bool GrOvalRenderer::drawOval(GrDrawTarget* target, const GrContext* context, const GrPaint& paint, |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 293 | const GrRect& oval, const SkStrokeRec& stroke) |
| 294 | { |
| 295 | if (!paint.isAntiAlias()) { |
| 296 | return false; |
| 297 | } |
| 298 | |
| 299 | const SkMatrix& vm = context->getMatrix(); |
| 300 | |
skia.committer@gmail.com | 7e32851 | 2013-03-23 07:01:28 +0000 | [diff] [blame] | 301 | // we can draw circles |
| 302 | if (SkScalarNearlyEqual(oval.width(), oval.height()) |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 303 | && circle_stays_circle(vm)) { |
| 304 | drawCircle(target, paint, oval, stroke); |
| 305 | |
| 306 | // and axis-aligned ellipses only |
| 307 | } else if (vm.rectStaysRect()) { |
| 308 | drawEllipse(target, paint, oval, stroke); |
| 309 | |
| 310 | } else { |
| 311 | return false; |
| 312 | } |
| 313 | |
| 314 | return true; |
| 315 | } |
| 316 | |
skia.committer@gmail.com | 7e32851 | 2013-03-23 07:01:28 +0000 | [diff] [blame] | 317 | void GrOvalRenderer::drawCircle(GrDrawTarget* target, |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 318 | const GrPaint& paint, |
| 319 | const GrRect& circle, |
| 320 | const SkStrokeRec& stroke) |
| 321 | { |
| 322 | GrDrawState* drawState = target->drawState(); |
| 323 | |
| 324 | const SkMatrix& vm = drawState->getViewMatrix(); |
| 325 | GrPoint center = GrPoint::Make(circle.centerX(), circle.centerY()); |
| 326 | vm.mapPoints(¢er, 1); |
| 327 | SkScalar radius = vm.mapRadius(SkScalarHalf(circle.width())); |
| 328 | SkScalar strokeWidth = vm.mapRadius(stroke.getWidth()); |
| 329 | |
| 330 | GrDrawState::AutoDeviceCoordDraw adcd(drawState); |
| 331 | if (!adcd.succeeded()) { |
| 332 | return; |
| 333 | } |
| 334 | |
| 335 | // position + edge |
| 336 | static const GrVertexAttrib kVertexAttribs[] = { |
jvanverth@google.com | 054ae99 | 2013-04-01 20:06:51 +0000 | [diff] [blame] | 337 | {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding}, |
| 338 | {kVec4f_GrVertexAttribType, sizeof(GrPoint), kEffect_GrVertexAttribBinding} |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 339 | }; |
| 340 | drawState->setVertexAttribs(kVertexAttribs, SK_ARRAY_COUNT(kVertexAttribs)); |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 341 | GrAssert(sizeof(CircleVertex) == drawState->getVertexSize()); |
| 342 | |
| 343 | GrDrawTarget::AutoReleaseGeometry geo(target, 4, 0); |
| 344 | if (!geo.succeeded()) { |
| 345 | GrPrintf("Failed to get space for vertices!\n"); |
| 346 | return; |
| 347 | } |
| 348 | |
| 349 | CircleVertex* verts = reinterpret_cast<CircleVertex*>(geo.vertices()); |
| 350 | |
| 351 | SkStrokeRec::Style style = stroke.getStyle(); |
| 352 | bool isStroked = (SkStrokeRec::kStroke_Style == style || SkStrokeRec::kHairline_Style == style); |
| 353 | enum { |
| 354 | // the edge effects share this stage with glyph rendering |
| 355 | // (kGlyphMaskStage in GrTextContext) && SW path rendering |
| 356 | // (kPathMaskStage in GrSWMaskHelper) |
| 357 | kEdgeEffectStage = GrPaint::kTotalStages, |
| 358 | }; |
skia.committer@gmail.com | 7e32851 | 2013-03-23 07:01:28 +0000 | [diff] [blame] | 359 | |
commit-bot@chromium.org | 90c240a | 2013-04-02 17:57:21 +0000 | [diff] [blame^] | 360 | GrEffectRef* effect = CircleEdgeEffect::Create(isStroked); |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 361 | static const int kCircleEdgeAttrIndex = 1; |
| 362 | drawState->setEffect(kEdgeEffectStage, effect, kCircleEdgeAttrIndex)->unref(); |
| 363 | |
| 364 | SkScalar innerRadius = 0.0f; |
| 365 | SkScalar outerRadius = radius; |
| 366 | SkScalar halfWidth = 0; |
| 367 | if (style != SkStrokeRec::kFill_Style) { |
| 368 | if (SkScalarNearlyZero(strokeWidth)) { |
| 369 | halfWidth = SK_ScalarHalf; |
| 370 | } else { |
| 371 | halfWidth = SkScalarHalf(strokeWidth); |
| 372 | } |
| 373 | |
| 374 | outerRadius += halfWidth; |
| 375 | if (isStroked) { |
| 376 | innerRadius = SkMaxScalar(0, radius - halfWidth); |
| 377 | } |
| 378 | } |
| 379 | |
bsalomon@google.com | 58e30fe | 2013-04-01 19:01:20 +0000 | [diff] [blame] | 380 | // The radii are outset for two reasons. First, it allows the shader to simply perform |
| 381 | // clamp(distance-to-center - radius, 0, 1). Second, the outer radius is used to compute the |
| 382 | // verts of the bounding box that is rendered and the outset ensures the box will cover all |
| 383 | // pixels partially covered by the circle. |
| 384 | outerRadius += SK_ScalarHalf; |
| 385 | innerRadius -= SK_ScalarHalf; |
| 386 | |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 387 | for (int i = 0; i < 4; ++i) { |
| 388 | verts[i].fCenter = center; |
bsalomon@google.com | 58e30fe | 2013-04-01 19:01:20 +0000 | [diff] [blame] | 389 | verts[i].fOuterRadius = outerRadius; |
| 390 | verts[i].fInnerRadius = innerRadius; |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 391 | } |
| 392 | |
commit-bot@chromium.org | bb5c465 | 2013-04-01 12:49:31 +0000 | [diff] [blame] | 393 | SkRect bounds = SkRect::MakeLTRB( |
bsalomon@google.com | 58e30fe | 2013-04-01 19:01:20 +0000 | [diff] [blame] | 394 | center.fX - outerRadius, |
| 395 | center.fY - outerRadius, |
| 396 | center.fX + outerRadius, |
| 397 | center.fY + outerRadius |
commit-bot@chromium.org | bb5c465 | 2013-04-01 12:49:31 +0000 | [diff] [blame] | 398 | ); |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 399 | |
commit-bot@chromium.org | bb5c465 | 2013-04-01 12:49:31 +0000 | [diff] [blame] | 400 | verts[0].fPos = SkPoint::Make(bounds.fLeft, bounds.fTop); |
| 401 | verts[1].fPos = SkPoint::Make(bounds.fRight, bounds.fTop); |
| 402 | verts[2].fPos = SkPoint::Make(bounds.fLeft, bounds.fBottom); |
| 403 | verts[3].fPos = SkPoint::Make(bounds.fRight, bounds.fBottom); |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 404 | |
commit-bot@chromium.org | bb5c465 | 2013-04-01 12:49:31 +0000 | [diff] [blame] | 405 | target->drawNonIndexed(kTriangleStrip_GrPrimitiveType, 0, 4, &bounds); |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 406 | } |
| 407 | |
skia.committer@gmail.com | 7e32851 | 2013-03-23 07:01:28 +0000 | [diff] [blame] | 408 | void GrOvalRenderer::drawEllipse(GrDrawTarget* target, |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 409 | const GrPaint& paint, |
| 410 | const GrRect& ellipse, |
| 411 | const SkStrokeRec& stroke) |
| 412 | { |
| 413 | GrDrawState* drawState = target->drawState(); |
| 414 | #ifdef SK_DEBUG |
| 415 | { |
| 416 | // we should have checked for this previously |
| 417 | bool isAxisAlignedEllipse = drawState->getViewMatrix().rectStaysRect(); |
| 418 | SkASSERT(paint.isAntiAlias() && isAxisAlignedEllipse); |
| 419 | } |
| 420 | #endif |
| 421 | |
| 422 | const SkMatrix& vm = drawState->getViewMatrix(); |
| 423 | GrPoint center = GrPoint::Make(ellipse.centerX(), ellipse.centerY()); |
| 424 | vm.mapPoints(¢er, 1); |
| 425 | SkRect xformedRect; |
| 426 | vm.mapRect(&xformedRect, ellipse); |
| 427 | |
| 428 | GrDrawState::AutoDeviceCoordDraw adcd(drawState); |
| 429 | if (!adcd.succeeded()) { |
| 430 | return; |
| 431 | } |
| 432 | |
| 433 | // position + edge |
| 434 | static const GrVertexAttrib kVertexAttribs[] = { |
jvanverth@google.com | 054ae99 | 2013-04-01 20:06:51 +0000 | [diff] [blame] | 435 | {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding}, |
| 436 | {kVec2f_GrVertexAttribType, sizeof(GrPoint), kEffect_GrVertexAttribBinding}, |
| 437 | {kVec4f_GrVertexAttribType, 2*sizeof(GrPoint), kEffect_GrVertexAttribBinding} |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 438 | }; |
| 439 | drawState->setVertexAttribs(kVertexAttribs, SK_ARRAY_COUNT(kVertexAttribs)); |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 440 | GrAssert(sizeof(EllipseVertex) == drawState->getVertexSize()); |
| 441 | |
| 442 | GrDrawTarget::AutoReleaseGeometry geo(target, 4, 0); |
| 443 | if (!geo.succeeded()) { |
| 444 | GrPrintf("Failed to get space for vertices!\n"); |
| 445 | return; |
| 446 | } |
| 447 | |
| 448 | EllipseVertex* verts = reinterpret_cast<EllipseVertex*>(geo.vertices()); |
| 449 | |
| 450 | SkStrokeRec::Style style = stroke.getStyle(); |
| 451 | bool isStroked = (SkStrokeRec::kStroke_Style == style || SkStrokeRec::kHairline_Style == style); |
| 452 | enum { |
| 453 | // the edge effects share this stage with glyph rendering |
| 454 | // (kGlyphMaskStage in GrTextContext) && SW path rendering |
| 455 | // (kPathMaskStage in GrSWMaskHelper) |
| 456 | kEdgeEffectStage = GrPaint::kTotalStages, |
| 457 | }; |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 458 | |
commit-bot@chromium.org | 90c240a | 2013-04-02 17:57:21 +0000 | [diff] [blame^] | 459 | GrEffectRef* effect = EllipseEdgeEffect::Create(isStroked); |
commit-bot@chromium.org | 8131283 | 2013-03-22 18:34:09 +0000 | [diff] [blame] | 460 | static const int kEllipseCenterAttrIndex = 1; |
| 461 | static const int kEllipseEdgeAttrIndex = 2; |
| 462 | drawState->setEffect(kEdgeEffectStage, effect, |
| 463 | kEllipseCenterAttrIndex, kEllipseEdgeAttrIndex)->unref(); |
| 464 | |
| 465 | SkScalar xRadius = SkScalarHalf(xformedRect.width()); |
| 466 | SkScalar yRadius = SkScalarHalf(xformedRect.height()); |
| 467 | SkScalar innerXRadius = 0.0f; |
| 468 | SkScalar innerRatio = 1.0f; |
| 469 | |
| 470 | if (SkStrokeRec::kFill_Style != style) { |
| 471 | SkScalar strokeWidth = stroke.getWidth(); |
| 472 | |
| 473 | // do (potentially) anisotropic mapping |
| 474 | SkVector scaledStroke; |
| 475 | scaledStroke.set(strokeWidth, strokeWidth); |
| 476 | vm.mapVectors(&scaledStroke, 1); |
| 477 | |
| 478 | if (SkScalarNearlyZero(scaledStroke.length())) { |
| 479 | scaledStroke.set(SK_ScalarHalf, SK_ScalarHalf); |
| 480 | } else { |
| 481 | scaledStroke.scale(0.5f); |
| 482 | } |
| 483 | |
| 484 | // this is legit only if scale & translation (which should be the case at the moment) |
| 485 | if (SkStrokeRec::kStroke_Style == style || SkStrokeRec::kHairline_Style == style) { |
| 486 | SkScalar innerYRadius = SkMaxScalar(0, yRadius - scaledStroke.fY); |
| 487 | if (innerYRadius > SK_ScalarNearlyZero) { |
| 488 | innerXRadius = SkMaxScalar(0, xRadius - scaledStroke.fX); |
| 489 | innerRatio = innerXRadius/innerYRadius; |
| 490 | } |
| 491 | } |
| 492 | xRadius += scaledStroke.fX; |
| 493 | yRadius += scaledStroke.fY; |
| 494 | } |
| 495 | |
| 496 | SkScalar outerRatio = SkScalarDiv(xRadius, yRadius); |
| 497 | |
| 498 | for (int i = 0; i < 4; ++i) { |
| 499 | verts[i].fCenter = center; |
| 500 | verts[i].fOuterXRadius = xRadius + 0.5f; |
| 501 | verts[i].fOuterXYRatio = outerRatio; |
| 502 | verts[i].fInnerXRadius = innerXRadius - 0.5f; |
| 503 | verts[i].fInnerXYRatio = innerRatio; |
| 504 | } |
| 505 | |
| 506 | SkScalar L = -xRadius; |
| 507 | SkScalar R = +xRadius; |
| 508 | SkScalar T = -yRadius; |
| 509 | SkScalar B = +yRadius; |
| 510 | |
| 511 | // We've extended the outer x radius out half a pixel to antialias. |
| 512 | // Expand the drawn rect here so all the pixels will be captured. |
| 513 | L += center.fX - SK_ScalarHalf; |
| 514 | R += center.fX + SK_ScalarHalf; |
| 515 | T += center.fY - SK_ScalarHalf; |
| 516 | B += center.fY + SK_ScalarHalf; |
| 517 | |
| 518 | verts[0].fPos = SkPoint::Make(L, T); |
| 519 | verts[1].fPos = SkPoint::Make(R, T); |
| 520 | verts[2].fPos = SkPoint::Make(L, B); |
| 521 | verts[3].fPos = SkPoint::Make(R, B); |
| 522 | |
| 523 | target->drawNonIndexed(kTriangleStrip_GrPrimitiveType, 0, 4); |
| 524 | } |