Add elliptical-corner rrect clip effect. Currently only handles the case where all corners have the same pair of radii.

BUG=skia:2181
R=jvanverth@google.com

Author: bsalomon@google.com

Review URL: https://codereview.chromium.org/194603004

git-svn-id: http://skia.googlecode.com/svn/trunk@13766 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 277 insertions, 70 deletions

diff --git a/src/gpu/effects/GrRRectEffect.cpp b/src/gpu/effects/GrRRectEffect.cpp
index 1bbf2f7976..1838cf0287 100644
--- a/src/gpu/effects/GrRRectEffect.cpp
+++ b/src/gpu/effects/GrRRectEffect.cpp
@@ -13,11 +13,9 @@
 
 #include "SkRRect.h"
 
-using namespace GrRRectEffect;
+class GLCircularRRectEffect;
 
-class GLRRectEffect;
-
-class RRectEffect : public GrEffect {
+class CircularRRectEffect : public GrEffect {
 public:
     // This effect only supports circular corner rrects where the radius is >= kRadiusMin.
     static const SkScalar kRadiusMin;
@@ -42,8 +40,8 @@ public:
     // be square).
     static GrEffectRef* Create(GrEffectEdgeType, uint32_t circularCornerFlags, const SkRRect&);
 
-    virtual ~RRectEffect() {};
-    static const char* Name() { return "RRect"; }
+    virtual ~CircularRRectEffect() {};
+    static const char* Name() { return "CircularRRect"; }
 
     const SkRRect& getRRect() const { return fRRect; }
 
@@ -51,14 +49,14 @@ public:
 
     GrEffectEdgeType getEdgeType() const { return fEdgeType; }
 
-    typedef GLRRectEffect GLEffect;
+    typedef GLCircularRRectEffect GLEffect;
 
     virtual void getConstantColorComponents(GrColor* color, uint32_t* validFlags) const SK_OVERRIDE;
 
     virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE;
 
 private:
-    RRectEffect(GrEffectEdgeType, uint32_t circularCornerFlags, const SkRRect&);
+    CircularRRectEffect(GrEffectEdgeType, uint32_t circularCornerFlags, const SkRRect&);
 
     virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE;
 
@@ -71,25 +69,25 @@ private:
     typedef GrEffect INHERITED;
 };
 
-const SkScalar RRectEffect::kRadiusMin = 0.5f;
+const SkScalar CircularRRectEffect::kRadiusMin = 0.5f;
 
-GrEffectRef* RRectEffect::Create(GrEffectEdgeType edgeType,
+GrEffectRef* CircularRRectEffect::Create(GrEffectEdgeType edgeType,
                                  uint32_t circularCornerFlags,
                                  const SkRRect& rrect) {
     SkASSERT(kFillAA_GrEffectEdgeType == edgeType || kInverseFillAA_GrEffectEdgeType == edgeType);
-    return CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(RRectEffect,
+    return CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(CircularRRectEffect,
                                                       (edgeType, circularCornerFlags, rrect))));
 }
 
-void RRectEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
+void CircularRRectEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
     *validFlags = 0;
 }
 
-const GrBackendEffectFactory& RRectEffect::getFactory() const {
-    return GrTBackendEffectFactory<RRectEffect>::getInstance();
+const GrBackendEffectFactory& CircularRRectEffect::getFactory() const {
+    return GrTBackendEffectFactory<CircularRRectEffect>::getInstance();
 }
 
-RRectEffect::RRectEffect(GrEffectEdgeType edgeType, uint32_t circularCornerFlags,
+CircularRRectEffect::CircularRRectEffect(GrEffectEdgeType edgeType, uint32_t circularCornerFlags,
                          const SkRRect& rrect)
     : fRRect(rrect)
     , fEdgeType(edgeType)
@@ -97,17 +95,17 @@ RRectEffect::RRectEffect(GrEffectEdgeType edgeType, uint32_t circularCornerFlags
     this->setWillReadFragmentPosition();
 }
 
-bool RRectEffect::onIsEqual(const GrEffect& other) const {
-    const RRectEffect& rre = CastEffect<RRectEffect>(other);
-    // type is derived from fRRect, so no need to check it.
-    return fEdgeType == rre.fEdgeType && fRRect == rre.fRRect;
+bool CircularRRectEffect::onIsEqual(const GrEffect& other) const {
+    const CircularRRectEffect& crre = CastEffect<CircularRRectEffect>(other);
+    // The corner flags are derived from fRRect, so no need to check them.
+    return fEdgeType == crre.fEdgeType && fRRect == crre.fRRect;
 }
 
 //////////////////////////////////////////////////////////////////////////////
 
-GR_DEFINE_EFFECT_TEST(RRectEffect);
+GR_DEFINE_EFFECT_TEST(CircularRRectEffect);
 
-GrEffectRef* RRectEffect::TestCreate(SkRandom* random,
+GrEffectRef* CircularRRectEffect::TestCreate(SkRandom* random,
                                      GrContext*,
                                      const GrDrawTargetCaps& caps,
                                      GrTexture*[]) {
@@ -126,9 +124,9 @@ GrEffectRef* RRectEffect::TestCreate(SkRandom* random,
 
 //////////////////////////////////////////////////////////////////////////////
 
-class GLRRectEffect : public GrGLEffect {
+class GLCircularRRectEffect : public GrGLEffect {
 public:
-    GLRRectEffect(const GrBackendEffectFactory&, const GrDrawEffect&);
+    GLCircularRRectEffect(const GrBackendEffectFactory&, const GrDrawEffect&);
 
     virtual void emitCode(GrGLShaderBuilder* builder,
                           const GrDrawEffect& drawEffect,
@@ -149,20 +147,20 @@ private:
     typedef GrGLEffect INHERITED;
 };
 
-GLRRectEffect::GLRRectEffect(const GrBackendEffectFactory& factory,
+GLCircularRRectEffect::GLCircularRRectEffect(const GrBackendEffectFactory& factory,
                              const GrDrawEffect& drawEffect)
     : INHERITED (factory) {
     fPrevRRect.setEmpty();
 }
 
-void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
+void GLCircularRRectEffect::emitCode(GrGLShaderBuilder* builder,
                              const GrDrawEffect& drawEffect,
                              EffectKey key,
                              const char* outputColor,
                              const char* inputColor,
                              const TransformedCoordsArray&,
                              const TextureSamplerArray& samplers) {
-    const RRectEffect& rre = drawEffect.castEffect<RRectEffect>();
+    const CircularRRectEffect& crre = drawEffect.castEffect<CircularRRectEffect>();
     const char *rectName;
     const char *radiusPlusHalfName;
     // The inner rect is the rrect bounds inset by the radius. Its left, top, right, and bottom
@@ -193,16 +191,17 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
     // For the cases where one half of the rrect is rectangular we drop one of the x or y
     // computations, compute a separate rect edge alpha for the rect side, and mul the two computed
     // alphas together.
-    switch (rre.getCircularCornerFlags()) {
-        case RRectEffect::kAll_CornerFlags:
+    switch (crre.getCircularCornerFlags()) {
+        case CircularRRectEffect::kAll_CornerFlags:
             builder->fsCodeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
             builder->fsCodeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
             builder->fsCodeAppend("\t\tvec2 dxy = max(max(dxy0, dxy1), 0.0);\n");
             builder->fsCodeAppendf("\t\tfloat alpha = clamp(%s - length(dxy), 0.0, 1.0);\n",
                                    radiusPlusHalfName);
             break;
-        case RRectEffect::kTopLeft_CornerFlag:
-            builder->fsCodeAppendf("\t\tvec2 dxy = max(%s.xy - %s.xy, 0.0);\n", rectName, fragmentPos);
+        case CircularRRectEffect::kTopLeft_CornerFlag:
+            builder->fsCodeAppendf("\t\tvec2 dxy = max(%s.xy - %s.xy, 0.0);\n",
+                                   rectName, fragmentPos);
             builder->fsCodeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n",
                                     rectName, fragmentPos);
             builder->fsCodeAppendf("\t\tfloat bottomAlpha = clamp(%s.w - %s.y, 0.0, 1.0);\n",
@@ -210,7 +209,7 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
             builder->fsCodeAppendf("\t\tfloat alpha = bottomAlpha * rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
                                    radiusPlusHalfName);
             break;
-        case RRectEffect::kTopRight_CornerFlag:
+        case CircularRRectEffect::kTopRight_CornerFlag:
             builder->fsCodeAppendf("\t\tvec2 dxy = max(vec2(%s.x - %s.z, %s.y - %s.y), 0.0);\n",
                                    fragmentPos, rectName, rectName, fragmentPos);
             builder->fsCodeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n",
@@ -220,7 +219,7 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
             builder->fsCodeAppendf("\t\tfloat alpha = bottomAlpha * leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
                                    radiusPlusHalfName);
             break;
-        case RRectEffect::kBottomRight_CornerFlag:
+        case CircularRRectEffect::kBottomRight_CornerFlag:
             builder->fsCodeAppendf("\t\tvec2 dxy = max(%s.xy - %s.zw, 0.0);\n",
                                    fragmentPos, rectName);
             builder->fsCodeAppendf("\t\tfloat leftAlpha = clamp(%s.x - %s.x, 0.0, 1.0);\n",
@@ -230,7 +229,7 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
             builder->fsCodeAppendf("\t\tfloat alpha = topAlpha * leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
                                    radiusPlusHalfName);
             break;
-        case RRectEffect::kBottomLeft_CornerFlag:
+        case CircularRRectEffect::kBottomLeft_CornerFlag:
             builder->fsCodeAppendf("\t\tvec2 dxy = max(vec2(%s.x - %s.x, %s.y - %s.w), 0.0);\n",
                                    rectName, fragmentPos, fragmentPos, rectName);
             builder->fsCodeAppendf("\t\tfloat rightAlpha = clamp(%s.z - %s.x, 0.0, 1.0);\n",
@@ -240,7 +239,7 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
             builder->fsCodeAppendf("\t\tfloat alpha = topAlpha * rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
                                    radiusPlusHalfName);
             break;
-        case RRectEffect::kLeft_CornerFlags:
+        case CircularRRectEffect::kLeft_CornerFlags:
             builder->fsCodeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
             builder->fsCodeAppendf("\t\tfloat dy1 = %s.y - %s.w;\n", fragmentPos, rectName);
             builder->fsCodeAppend("\t\tvec2 dxy = max(vec2(dxy0.x, max(dxy0.y, dy1)), 0.0);\n");
@@ -249,7 +248,7 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
             builder->fsCodeAppendf("\t\tfloat alpha = rightAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
                                    radiusPlusHalfName);
             break;
-        case RRectEffect::kTop_CornerFlags:
+        case CircularRRectEffect::kTop_CornerFlags:
             builder->fsCodeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
             builder->fsCodeAppendf("\t\tfloat dx1 = %s.x - %s.z;\n", fragmentPos, rectName);
             builder->fsCodeAppend("\t\tvec2 dxy = max(vec2(max(dxy0.x, dx1), dxy0.y), 0.0);\n");
@@ -258,7 +257,7 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
             builder->fsCodeAppendf("\t\tfloat alpha = bottomAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
                                    radiusPlusHalfName);
             break;
-        case RRectEffect::kRight_CornerFlags:
+        case CircularRRectEffect::kRight_CornerFlags:
             builder->fsCodeAppendf("\t\tfloat dy0 = %s.y - %s.y;\n", rectName, fragmentPos);
             builder->fsCodeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
             builder->fsCodeAppend("\t\tvec2 dxy = max(vec2(dxy1.x, max(dy0, dxy1.y)), 0.0);\n");
@@ -267,7 +266,7 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
             builder->fsCodeAppendf("\t\tfloat alpha = leftAlpha * clamp(%s - length(dxy), 0.0, 1.0);\n",
                                    radiusPlusHalfName);
             break;
-        case RRectEffect::kBottom_CornerFlags:
+        case CircularRRectEffect::kBottom_CornerFlags:
             builder->fsCodeAppendf("\t\tfloat dx0 = %s.x - %s.x;\n", rectName, fragmentPos);
             builder->fsCodeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
             builder->fsCodeAppend("\t\tvec2 dxy = max(vec2(max(dx0, dxy1.x), dxy1.y), 0.0);\n");
@@ -278,7 +277,7 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
             break;
     }
 
-    if (kInverseFillAA_GrEffectEdgeType == rre.getEdgeType()) {
+    if (kInverseFillAA_GrEffectEdgeType == crre.getEdgeType()) {
         builder->fsCodeAppend("\t\talpha = 1.0 - alpha;\n");
     }
 
@@ -286,75 +285,77 @@ void GLRRectEffect::emitCode(GrGLShaderBuilder* builder,
                            (GrGLSLExpr4(inputColor) * GrGLSLExpr1("alpha")).c_str());
 }
 
-GrGLEffect::EffectKey GLRRectEffect::GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) {
-    const RRectEffect& rre = drawEffect.castEffect<RRectEffect>();
+GrGLEffect::EffectKey GLCircularRRectEffect::GenKey(const GrDrawEffect& drawEffect,
+                                                    const GrGLCaps&) {
+    const CircularRRectEffect& crre = drawEffect.castEffect<CircularRRectEffect>();
     GR_STATIC_ASSERT(kGrEffectEdgeTypeCnt <= 8);
-    return (rre.getCircularCornerFlags() << 3) | rre.getEdgeType();
+    return (crre.getCircularCornerFlags() << 3) | crre.getEdgeType();
 }
 
-void GLRRectEffect::setData(const GrGLUniformManager& uman, const GrDrawEffect& drawEffect) {
-    const RRectEffect& rre = drawEffect.castEffect<RRectEffect>();
-    const SkRRect& rrect = rre.getRRect();
+void GLCircularRRectEffect::setData(const GrGLUniformManager& uman,
+                                    const GrDrawEffect& drawEffect) {
+    const CircularRRectEffect& crre = drawEffect.castEffect<CircularRRectEffect>();
+    const SkRRect& rrect = crre.getRRect();
     if (rrect != fPrevRRect) {
         SkRect rect = rrect.getBounds();
         SkScalar radius = 0;
-        switch (rre.getCircularCornerFlags()) {
-            case RRectEffect::kAll_CornerFlags:
+        switch (crre.getCircularCornerFlags()) {
+            case CircularRRectEffect::kAll_CornerFlags:
                 SkASSERT(rrect.isSimpleCircular());
                 radius = rrect.getSimpleRadii().fX;
-                SkASSERT(radius >= RRectEffect::kRadiusMin);
+                SkASSERT(radius >= CircularRRectEffect::kRadiusMin);
                 rect.inset(radius, radius);
                 break;
-            case RRectEffect::kTopLeft_CornerFlag:
+            case CircularRRectEffect::kTopLeft_CornerFlag:
                 radius = rrect.radii(SkRRect::kUpperLeft_Corner).fX;
                 rect.fLeft += radius;
                 rect.fTop += radius;
                 rect.fRight += 0.5f;
                 rect.fBottom += 0.5f;
                 break;
-            case RRectEffect::kTopRight_CornerFlag:
+            case CircularRRectEffect::kTopRight_CornerFlag:
                 radius = rrect.radii(SkRRect::kUpperRight_Corner).fX;
                 rect.fLeft -= 0.5f;
                 rect.fTop += radius;
                 rect.fRight -= radius;
                 rect.fBottom += 0.5f;
                 break;
-            case RRectEffect::kBottomRight_CornerFlag:
+            case CircularRRectEffect::kBottomRight_CornerFlag:
                 radius = rrect.radii(SkRRect::kLowerRight_Corner).fX;
                 rect.fLeft -= 0.5f;
                 rect.fTop -= 0.5f;
                 rect.fRight -= radius;
                 rect.fBottom -= radius;
                 break;
-            case RRectEffect::kBottomLeft_CornerFlag:
+            case CircularRRectEffect::kBottomLeft_CornerFlag:
                 radius = rrect.radii(SkRRect::kLowerLeft_Corner).fX;
                 rect.fLeft += radius;
                 rect.fTop -= 0.5f;
                 rect.fRight += 0.5f;
                 rect.fBottom -= radius;
                 break;
-            case RRectEffect::kLeft_CornerFlags:
+            case CircularRRectEffect::kLeft_CornerFlags:
                 radius = rrect.radii(SkRRect::kUpperLeft_Corner).fX;
                 rect.fLeft += radius;
                 rect.fTop += radius;
                 rect.fRight += 0.5f;
                 rect.fBottom -= radius;
                 break;
-            case RRectEffect::kTop_CornerFlags:
+            case CircularRRectEffect::kTop_CornerFlags:
                 radius = rrect.radii(SkRRect::kUpperLeft_Corner).fX;
                 rect.fLeft += radius;
                 rect.fTop += radius;
                 rect.fRight -= radius;
                 rect.fBottom += 0.5f;
                 break;
-            case RRectEffect::kRight_CornerFlags:
+            case CircularRRectEffect::kRight_CornerFlags:
                 radius = rrect.radii(SkRRect::kUpperRight_Corner).fX;
                 rect.fLeft -= 0.5f;
                 rect.fTop += radius;
                 rect.fRight -= radius;
                 rect.fBottom -= radius;
                 break;
-            case RRectEffect::kBottom_CornerFlags:
+            case CircularRRectEffect::kBottom_CornerFlags:
                 radius = rrect.radii(SkRRect::kLowerLeft_Corner).fX;
                 rect.fLeft += radius;
                 rect.fTop -= 0.5f;
@@ -372,16 +373,222 @@ void GLRRectEffect::setData(const GrGLUniformManager& uman, const GrDrawEffect&
 
 //////////////////////////////////////////////////////////////////////////////
 
+class GLEllipticalRRectEffect;
+
+/**
+ * Currently this effect only supports "simple" elliptical round rects (i.e.
+ * the corners all have a common x/y radii pair).
+ */
+class EllipticalRRectEffect : public GrEffect {
+public:
+    // This effect only supports rrects where the radii are >= kRadiusMin
+    static const SkScalar kRadiusMin;
+
+    static GrEffectRef* Create(GrEffectEdgeType, const SkRRect&);
+
+    virtual ~EllipticalRRectEffect() {};
+    static const char* Name() { return "EllipticalRRect"; }
+
+    const SkRRect& getRRect() const { return fRRect; }
+
+    GrEffectEdgeType getEdgeType() const { return fEdgeType; }
+
+    typedef GLEllipticalRRectEffect GLEffect;
+
+    virtual void getConstantColorComponents(GrColor* color, uint32_t* validFlags) const SK_OVERRIDE;
+
+    virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE;
+
+private:
+    EllipticalRRectEffect(GrEffectEdgeType, const SkRRect&);
+
+    virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE;
+
+    SkRRect             fRRect;
+    GrEffectEdgeType    fEdgeType;
+
+    GR_DECLARE_EFFECT_TEST;
+
+    typedef GrEffect INHERITED;
+};
+
+const SkScalar EllipticalRRectEffect::kRadiusMin = 0.5f;
+
+GrEffectRef* EllipticalRRectEffect::Create(GrEffectEdgeType edgeType,
+                                           const SkRRect& rrect) {
+    SkASSERT(kFillAA_GrEffectEdgeType == edgeType || kInverseFillAA_GrEffectEdgeType == edgeType);
+    return CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(EllipticalRRectEffect, (edgeType, rrect))));
+}
+
+void EllipticalRRectEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
+    *validFlags = 0;
+}
+
+const GrBackendEffectFactory& EllipticalRRectEffect::getFactory() const {
+    return GrTBackendEffectFactory<EllipticalRRectEffect>::getInstance();
+}
+
+EllipticalRRectEffect::EllipticalRRectEffect(GrEffectEdgeType edgeType, const SkRRect& rrect)
+    : fRRect(rrect)
+    , fEdgeType(edgeType){
+    this->setWillReadFragmentPosition();
+}
+
+bool EllipticalRRectEffect::onIsEqual(const GrEffect& other) const {
+    const EllipticalRRectEffect& erre = CastEffect<EllipticalRRectEffect>(other);
+    return fEdgeType == erre.fEdgeType && fRRect == erre.fRRect;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+
+GR_DEFINE_EFFECT_TEST(EllipticalRRectEffect);
+
+GrEffectRef* EllipticalRRectEffect::TestCreate(SkRandom* random,
+                                               GrContext*,
+                                               const GrDrawTargetCaps& caps,
+                                               GrTexture*[]) {
+    SkScalar w = random->nextRangeScalar(20.f, 1000.f);
+    SkScalar h = random->nextRangeScalar(20.f, 1000.f);
+    SkScalar rx = random->nextRangeF(kRadiusMin, 9.f);
+    SkScalar ry = random->nextRangeF(kRadiusMin, 9.f);
+    SkRRect rrect;
+    rrect.setRectXY(SkRect::MakeWH(w, h), rx, ry);
+    GrEffectRef* effect;
+    do {
+        GrEffectEdgeType et = (GrEffectEdgeType)random->nextULessThan(kGrEffectEdgeTypeCnt);
+        effect = EllipticalRRectEffect::Create(et, rrect);
+    } while (NULL == effect);
+    return effect;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+
+class GLEllipticalRRectEffect : public GrGLEffect {
+public:
+    GLEllipticalRRectEffect(const GrBackendEffectFactory&, const GrDrawEffect&);
+
+    virtual void emitCode(GrGLShaderBuilder* builder,
+                          const GrDrawEffect& drawEffect,
+                          EffectKey key,
+                          const char* outputColor,
+                          const char* inputColor,
+                          const TransformedCoordsArray&,
+                          const TextureSamplerArray&) SK_OVERRIDE;
+
+    static inline EffectKey GenKey(const GrDrawEffect&, const GrGLCaps&);
+
+    virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE;
+
+private:
+    GrGLUniformManager::UniformHandle   fInnerRectUniform;
+    GrGLUniformManager::UniformHandle   fInvRadiusXYSqdUniform;
+    SkRRect                             fPrevRRect;
+    typedef GrGLEffect INHERITED;
+};
+
+GLEllipticalRRectEffect::GLEllipticalRRectEffect(const GrBackendEffectFactory& factory,
+                             const GrDrawEffect& drawEffect)
+    : INHERITED (factory) {
+    fPrevRRect.setEmpty();
+}
+
+void GLEllipticalRRectEffect::emitCode(GrGLShaderBuilder* builder,
+                                       const GrDrawEffect& drawEffect,
+                                       EffectKey key,
+                                       const char* outputColor,
+                                       const char* inputColor,
+                                       const TransformedCoordsArray&,
+                                       const TextureSamplerArray& samplers) {
+    const EllipticalRRectEffect& erre = drawEffect.castEffect<EllipticalRRectEffect>();
+    const char *rectName;
+    const char *invRadiusXYSqdName;
+    // The inner rect is the rrect bounds inset by the x/y radii
+    fInnerRectUniform = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
+                                            kVec4f_GrSLType,
+                                            "innerRect",
+                                            &rectName);
+    fInvRadiusXYSqdUniform = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
+                                              kVec2f_GrSLType,
+                                              "invRadiusXY",
+                                              &invRadiusXYSqdName);
+    const char* fragmentPos = builder->fragmentPosition();
+    // At each quarter-ellipse corner we compute a vector that is the offset of the fragment pos
+    // to the ellipse center. The vector is pinned in x and y to be in the quarter-plane relevant
+    // to that corner. This means that points near the interior near the rrect top edge will have
+    // a vector that points straight up for both the TL left and TR corners. Computing an
+    // alpha from this vector at either the TR or TL corner will give the correct result. Similarly,
+    // fragments near the other three edges will get the correct AA. Fragments in the interior of
+    // the rrect will have a (0,0) vector at all four corners. So long as the radii > 0.5 they will
+    // correctly produce an alpha value of 1 at all four corners. We take the min of all the alphas.
+    // The code below is a simplified version of the above that performs maxs on the vector
+    // components before computing distances and alpha values so that only one distance computation
+    // need be computed to determine the min alpha.
+    builder->fsCodeAppendf("\t\tvec2 dxy0 = %s.xy - %s.xy;\n", rectName, fragmentPos);
+    builder->fsCodeAppendf("\t\tvec2 dxy1 = %s.xy - %s.zw;\n", fragmentPos, rectName);
+    builder->fsCodeAppend("\t\tvec2 dxy = max(max(dxy0, dxy1), 0.0);\n");
+    // Z is the x/y offsets divided by squared radii.
+    builder->fsCodeAppendf("\t\tvec2 Z = dxy * %s;\n", invRadiusXYSqdName);
+    // implicit is the evaluation of (x/a)^2 + (y/b)^2 - 1.
+    builder->fsCodeAppend("\t\tfloat implicit = dot(Z, dxy) - 1.0;\n");
+    // grad_dot is the squared length of the gradient of the implicit.
+    builder->fsCodeAppendf("\t\tfloat grad_dot = 4.0 * dot(Z, Z);\n");
+    builder->fsCodeAppend("\t\tgrad_dot = max(grad_dot, 1.0e-4);\n");
+    builder->fsCodeAppendf("\t\tfloat approx_dist = implicit * inversesqrt(grad_dot);\n");
+
+    if (kFillAA_GrEffectEdgeType == erre.getEdgeType()) {
+        builder->fsCodeAppend("\t\tfloat alpha = clamp(0.5 - approx_dist, 0.0, 1.0);\n");
+    } else {
+        builder->fsCodeAppend("\t\tfloat alpha = clamp(0.5 + approx_dist, 0.0, 1.0);\n");
+    }
+
+    builder->fsCodeAppendf("\t\t%s = %s;\n", outputColor,
+                           (GrGLSLExpr4(inputColor) * GrGLSLExpr1("alpha")).c_str());
+}
+
+GrGLEffect::EffectKey GLEllipticalRRectEffect::GenKey(const GrDrawEffect& drawEffect,
+                                                      const GrGLCaps&) {
+    const EllipticalRRectEffect& erre = drawEffect.castEffect<EllipticalRRectEffect>();
+    return erre.getEdgeType();
+}
+
+void GLEllipticalRRectEffect::setData(const GrGLUniformManager& uman,
+                                      const GrDrawEffect& drawEffect) {
+    const EllipticalRRectEffect& erre = drawEffect.castEffect<EllipticalRRectEffect>();
+    const SkRRect& rrect = erre.getRRect();
+    if (rrect != fPrevRRect) {
+        SkRect rect = rrect.getBounds();
+        SkASSERT(rrect.isSimple());
+        const SkVector& radius = rrect.getSimpleRadii();
+        SkASSERT(radius.fX >= EllipticalRRectEffect::kRadiusMin);
+        SkASSERT(radius.fY >= EllipticalRRectEffect::kRadiusMin);
+        rect.inset(radius.fX, radius.fY);
+        uman.set4f(fInnerRectUniform, rect.fLeft, rect.fTop, rect.fRight, rect.fBottom);
+        uman.set2f(fInvRadiusXYSqdUniform, 1.f / (radius.fX * radius.fX),
+                                           1.f / (radius.fY * radius.fY));
+        fPrevRRect = rrect;
+    }
+}
+
+//////////////////////////////////////////////////////////////////////////////
+
 GrEffectRef* GrRRectEffect::Create(GrEffectEdgeType edgeType, const SkRRect& rrect) {
     if (kFillAA_GrEffectEdgeType != edgeType && kInverseFillAA_GrEffectEdgeType != edgeType) {
         return NULL;
     }
     uint32_t cornerFlags;
-    if (rrect.isSimpleCircular()) {
-        if (rrect.getSimpleRadii().fX < RRectEffect::kRadiusMin) {
-            return NULL;
+    if (rrect.isSimple()) {
+        if (rrect.getSimpleRadii().fX == rrect.getSimpleRadii().fY) {
+            if (rrect.getSimpleRadii().fX < CircularRRectEffect::kRadiusMin) {
+                return NULL;
+            }
+            cornerFlags = CircularRRectEffect::kAll_CornerFlags;
+        } else {
+            if (rrect.getSimpleRadii().fX < EllipticalRRectEffect::kRadiusMin ||
+                rrect.getSimpleRadii().fY < EllipticalRRectEffect::kRadiusMin) {
+                return NULL;
+            }
+            return EllipticalRRectEffect::Create(edgeType, rrect);
         }
-        cornerFlags = RRectEffect::kAll_CornerFlags;
     } else if (rrect.isComplex()) {
         // Check for the "tab" cases - two adjacent circular corners and two square corners.
         SkScalar radius = 0;
@@ -397,7 +604,7 @@ GrEffectRef* GrRRectEffect::Create(GrEffectEdgeType edgeType, const SkRRect& rre
             }
             if (!cornerFlags) {
                 radius = r.fX;
-                if (radius < RRectEffect::kRadiusMin) {
+                if (radius < CircularRRectEffect::kRadiusMin) {
                     return NULL;
                 }
                 cornerFlags = 1 << c;
@@ -410,15 +617,15 @@ GrEffectRef* GrRRectEffect::Create(GrEffectEdgeType edgeType, const SkRRect& rre
         }
 
         switch (cornerFlags) {
-            case RRectEffect::kTopLeft_CornerFlag:
-            case RRectEffect::kTopRight_CornerFlag:
-            case RRectEffect::kBottomRight_CornerFlag:
-            case RRectEffect::kBottomLeft_CornerFlag:
-            case RRectEffect::kLeft_CornerFlags:
-            case RRectEffect::kTop_CornerFlags:
-            case RRectEffect::kRight_CornerFlags:
-            case RRectEffect::kBottom_CornerFlags:
-            case RRectEffect::kAll_CornerFlags:
+            case CircularRRectEffect::kTopLeft_CornerFlag:
+            case CircularRRectEffect::kTopRight_CornerFlag:
+            case CircularRRectEffect::kBottomRight_CornerFlag:
+            case CircularRRectEffect::kBottomLeft_CornerFlag:
+            case CircularRRectEffect::kLeft_CornerFlags:
+            case CircularRRectEffect::kTop_CornerFlags:
+            case CircularRRectEffect::kRight_CornerFlags:
+            case CircularRRectEffect::kBottom_CornerFlags:
+            case CircularRRectEffect::kAll_CornerFlags:
                 break;
             default:
                 return NULL;
@@ -426,5 +633,5 @@ GrEffectRef* GrRRectEffect::Create(GrEffectEdgeType edgeType, const SkRRect& rre
     } else {
         return NULL;
     }
-    return RRectEffect::Create(edgeType, cornerFlags, rrect);
+    return CircularRRectEffect::Create(edgeType, cornerFlags, rrect);
 }