Add clip effect for circles
BUG=skia:2181
R=jvanverth@google.com
Author: bsalomon@google.com
Review URL: https://codereview.chromium.org/214153002
git-svn-id: http://skia.googlecode.com/svn/trunk@13974 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/src/gpu/effects/GrOvalEffect.cpp b/src/gpu/effects/GrOvalEffect.cpp
new file mode 100644
index 0000000..0a07cfe
--- /dev/null
+++ b/src/gpu/effects/GrOvalEffect.cpp
@@ -0,0 +1,193 @@
+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "GrOvalEffect.h"
+
+#include "gl/GrGLEffect.h"
+#include "gl/GrGLSL.h"
+#include "GrTBackendEffectFactory.h"
+
+#include "SkRect.h"
+
+//////////////////////////////////////////////////////////////////////////////
+
+class GLCircleEffect;
+
+class CircleEffect : public GrEffect {
+public:
+ static GrEffectRef* Create(GrEffectEdgeType, const SkPoint& center, SkScalar radius);
+
+ virtual ~CircleEffect() {};
+ static const char* Name() { return "Circle"; }
+
+ const SkPoint& getCenter() const { return fCenter; }
+ SkScalar getRadius() const { return fRadius; }
+
+ GrEffectEdgeType getEdgeType() const { return fEdgeType; }
+
+ typedef GLCircleEffect GLEffect;
+
+ virtual void getConstantColorComponents(GrColor* color, uint32_t* validFlags) const SK_OVERRIDE;
+
+ virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE;
+
+private:
+ CircleEffect(GrEffectEdgeType, const SkPoint& center, SkScalar radius);
+
+ virtual bool onIsEqual(const GrEffect&) const SK_OVERRIDE;
+
+ SkPoint fCenter;
+ SkScalar fRadius;
+ GrEffectEdgeType fEdgeType;
+
+ GR_DECLARE_EFFECT_TEST;
+
+ typedef GrEffect INHERITED;
+};
+
+GrEffectRef* CircleEffect::Create(GrEffectEdgeType edgeType,
+ const SkPoint& center,
+ SkScalar radius) {
+ SkASSERT(radius >= 0);
+ return CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(CircleEffect,
+ (edgeType, center, radius))));
+}
+
+void CircleEffect::getConstantColorComponents(GrColor* color, uint32_t* validFlags) const {
+ *validFlags = 0;
+}
+
+const GrBackendEffectFactory& CircleEffect::getFactory() const {
+ return GrTBackendEffectFactory<CircleEffect>::getInstance();
+}
+
+CircleEffect::CircleEffect(GrEffectEdgeType edgeType, const SkPoint& c, SkScalar r)
+ : fCenter(c)
+ , fRadius(r)
+ , fEdgeType(edgeType) {
+ this->setWillReadFragmentPosition();
+}
+
+bool CircleEffect::onIsEqual(const GrEffect& other) const {
+ const CircleEffect& crre = CastEffect<CircleEffect>(other);
+ return fEdgeType == crre.fEdgeType && fCenter == crre.fCenter && fRadius == crre.fRadius;
+}
+
+//////////////////////////////////////////////////////////////////////////////
+
+GR_DEFINE_EFFECT_TEST(CircleEffect);
+
+GrEffectRef* CircleEffect::TestCreate(SkRandom* random,
+ GrContext*,
+ const GrDrawTargetCaps& caps,
+ GrTexture*[]) {
+ SkPoint center;
+ center.fX = random->nextRangeScalar(0.f, 1000.f);
+ center.fY = random->nextRangeScalar(0.f, 1000.f);
+ SkScalar radius = random->nextRangeF(0.f, 1000.f);
+ GrEffectEdgeType et;
+ do {
+ et = (GrEffectEdgeType)random->nextULessThan(kGrEffectEdgeTypeCnt);
+ } while (kHairlineAA_GrEffectEdgeType == et);
+ return CircleEffect::Create(et, center, radius);
+}
+
+//////////////////////////////////////////////////////////////////////////////
+
+class GLCircleEffect : public GrGLEffect {
+public:
+ GLCircleEffect(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 fCircleUniform;
+ SkPoint fPrevCenter;
+ SkScalar fPrevRadius;
+
+ typedef GrGLEffect INHERITED;
+};
+
+GLCircleEffect::GLCircleEffect(const GrBackendEffectFactory& factory,
+ const GrDrawEffect& drawEffect)
+ : INHERITED (factory) {
+ fPrevRadius = -1.f;
+}
+
+void GLCircleEffect::emitCode(GrGLShaderBuilder* builder,
+ const GrDrawEffect& drawEffect,
+ EffectKey key,
+ const char* outputColor,
+ const char* inputColor,
+ const TransformedCoordsArray&,
+ const TextureSamplerArray& samplers) {
+ const CircleEffect& ce = drawEffect.castEffect<CircleEffect>();
+ const char *circleName;
+ // The circle uniform is (center.x, center.y, radius + 0.5)
+ fCircleUniform = builder->addUniform(GrGLShaderBuilder::kFragment_Visibility,
+ kVec3f_GrSLType,
+ "circle",
+ &circleName);
+ const char* fragmentPos = builder->fragmentPosition();
+
+ SkASSERT(kHairlineAA_GrEffectEdgeType != ce.getEdgeType());
+ if (GrEffectEdgeTypeIsInverseFill(ce.getEdgeType())) {
+ builder->fsCodeAppendf("\t\tfloat d = length(%s.xy - %s.xy) - %s.z;\n",
+ circleName, fragmentPos, circleName);
+ } else {
+ builder->fsCodeAppendf("\t\tfloat d = %s.z - length(%s.xy - %s.xy);\n",
+ circleName, fragmentPos, circleName);
+ }
+ if (GrEffectEdgeTypeIsAA(ce.getEdgeType())) {
+ builder->fsCodeAppend("\t\td = clamp(d, 0.0, 1.0);\n");
+ } else {
+ builder->fsCodeAppend("\t\td = d > 0.5 ? 1.0 : 0.0;\n");
+ }
+
+ builder->fsCodeAppendf("\t\t%s = %s;\n", outputColor,
+ (GrGLSLExpr4(inputColor) * GrGLSLExpr1("d")).c_str());
+}
+
+GrGLEffect::EffectKey GLCircleEffect::GenKey(const GrDrawEffect& drawEffect,
+ const GrGLCaps&) {
+ const CircleEffect& ce = drawEffect.castEffect<CircleEffect>();
+ return ce.getEdgeType();
+}
+
+void GLCircleEffect::setData(const GrGLUniformManager& uman, const GrDrawEffect& drawEffect) {
+ const CircleEffect& ce = drawEffect.castEffect<CircleEffect>();
+ if (ce.getRadius() != fPrevRadius || ce.getCenter() != fPrevCenter) {
+ uman.set3f(fCircleUniform, ce.getCenter().fX, ce.getCenter().fY, ce.getRadius() + 0.5f);
+ fPrevCenter = ce.getCenter();
+ fPrevRadius = ce.getRadius();
+ }
+}
+//////////////////////////////////////////////////////////////////////////////
+
+GrEffectRef* GrOvalEffect::Create(GrEffectEdgeType edgeType, const SkRect& oval) {
+ if (kHairlineAA_GrEffectEdgeType == edgeType) {
+ return NULL;
+ }
+ SkScalar w = oval.width();
+ SkScalar h = oval.height();
+ if (SkScalarNearlyEqual(w, h)) {
+ w /= 2;
+ return CircleEffect::Create(edgeType, SkPoint::Make(oval.fLeft + w, oval.fTop + w), w);
+ }
+
+ return NULL;
+}
diff --git a/src/gpu/effects/GrOvalEffect.h b/src/gpu/effects/GrOvalEffect.h
new file mode 100644
index 0000000..796ee5b
--- /dev/null
+++ b/src/gpu/effects/GrOvalEffect.h
@@ -0,0 +1,24 @@
+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef GrOvalEffect_DEFINED
+#define GrOvalEffect_DEFINED
+
+#include "GrTypes.h"
+#include "GrTypesPriv.h"
+
+class GrEffectRef;
+struct SkRect;
+
+namespace GrOvalEffect {
+ /**
+ * Creates an effect that performs clipping against an oval.
+ */
+ GrEffectRef* Create(GrEffectEdgeType, const SkRect&);
+};
+
+#endif
diff --git a/src/gpu/effects/GrRRectEffect.cpp b/src/gpu/effects/GrRRectEffect.cpp
index eff4aa8..1e93eb1 100644
--- a/src/gpu/effects/GrRRectEffect.cpp
+++ b/src/gpu/effects/GrRRectEffect.cpp
@@ -10,6 +10,7 @@
#include "gl/GrGLEffect.h"
#include "gl/GrGLSL.h"
#include "GrConvexPolyEffect.h"
+#include "GrOvalEffect.h"
#include "GrTBackendEffectFactory.h"
#include "SkRRect.h"
@@ -77,7 +78,9 @@
GrEffectRef* CircularRRectEffect::Create(GrEffectEdgeType edgeType,
uint32_t circularCornerFlags,
const SkRRect& rrect) {
- SkASSERT(kFillAA_GrEffectEdgeType == edgeType || kInverseFillAA_GrEffectEdgeType == edgeType);
+ if (kFillAA_GrEffectEdgeType != edgeType && kInverseFillAA_GrEffectEdgeType != edgeType) {
+ return NULL;
+ }
return CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(CircularRRectEffect,
(edgeType, circularCornerFlags, rrect))));
}
@@ -410,7 +413,9 @@
};
GrEffectRef* EllipticalRRectEffect::Create(GrEffectEdgeType edgeType, const SkRRect& rrect) {
- SkASSERT(kFillAA_GrEffectEdgeType == edgeType || kInverseFillAA_GrEffectEdgeType == edgeType);
+ if (kFillAA_GrEffectEdgeType != edgeType && kInverseFillAA_GrEffectEdgeType != edgeType) {
+ return NULL;
+ }
return CreateEffectRef(AutoEffectUnref(SkNEW_ARGS(EllipticalRRectEffect, (edgeType, rrect))));
}
@@ -627,14 +632,14 @@
//////////////////////////////////////////////////////////////////////////////
GrEffectRef* GrRRectEffect::Create(GrEffectEdgeType edgeType, const SkRRect& rrect) {
- if (kFillAA_GrEffectEdgeType != edgeType && kInverseFillAA_GrEffectEdgeType != edgeType) {
- return NULL;
- }
-
if (rrect.isRect()) {
return GrConvexPolyEffect::Create(edgeType, rrect.getBounds());
}
+ if (rrect.isOval()) {
+ return GrOvalEffect::Create(edgeType, rrect.getBounds());
+ }
+
if (rrect.isSimple()) {
if (rrect.getSimpleRadii().fX < kRadiusMin || rrect.getSimpleRadii().fY < kRadiusMin) {
// In this case the corners are extremely close to rectangular and we collapse the