diff -r 000000000000 -r 6474c204b198 gfx/skia/trunk/src/gpu/GrOvalRenderer.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/gfx/skia/trunk/src/gpu/GrOvalRenderer.cpp Wed Dec 31 06:09:35 2014 +0100 @@ -0,0 +1,1147 @@ +/* + * Copyright 2013 Google Inc. + * + * Use of this source code is governed by a BSD-style license that can be + * found in the LICENSE file. + */ + +#include "GrOvalRenderer.h" + +#include "GrEffect.h" +#include "gl/GrGLEffect.h" +#include "gl/GrGLSL.h" +#include "gl/GrGLVertexEffect.h" +#include "GrTBackendEffectFactory.h" + +#include "GrDrawState.h" +#include "GrDrawTarget.h" +#include "GrGpu.h" + +#include "SkRRect.h" +#include "SkStrokeRec.h" + +#include "effects/GrVertexEffect.h" + +namespace { + +struct CircleVertex { + GrPoint fPos; + GrPoint fOffset; + SkScalar fOuterRadius; + SkScalar fInnerRadius; +}; + +struct EllipseVertex { + GrPoint fPos; + GrPoint fOffset; + GrPoint fOuterRadii; + GrPoint fInnerRadii; +}; + +struct DIEllipseVertex { + GrPoint fPos; + GrPoint fOuterOffset; + GrPoint fInnerOffset; +}; + +inline bool circle_stays_circle(const SkMatrix& m) { + return m.isSimilarity(); +} + +} + +/////////////////////////////////////////////////////////////////////////////// + +/** + * The output of this effect is a modulation of the input color and coverage for a circle, + * specified as offset_x, offset_y (both from center point), outer radius and inner radius. + */ + +class CircleEdgeEffect : public GrVertexEffect { +public: + static GrEffectRef* Create(bool stroke) { + GR_CREATE_STATIC_EFFECT(gCircleStrokeEdge, CircleEdgeEffect, (true)); + GR_CREATE_STATIC_EFFECT(gCircleFillEdge, CircleEdgeEffect, (false)); + + if (stroke) { + gCircleStrokeEdge->ref(); + return gCircleStrokeEdge; + } else { + gCircleFillEdge->ref(); + return gCircleFillEdge; + } + } + + virtual void getConstantColorComponents(GrColor* color, + uint32_t* validFlags) const SK_OVERRIDE { + *validFlags = 0; + } + + virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE { + return GrTBackendEffectFactory::getInstance(); + } + + virtual ~CircleEdgeEffect() {} + + static const char* Name() { return "CircleEdge"; } + + inline bool isStroked() const { return fStroke; } + + class GLEffect : public GrGLVertexEffect { + public: + GLEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&) + : INHERITED (factory) {} + + virtual void emitCode(GrGLFullShaderBuilder* builder, + const GrDrawEffect& drawEffect, + EffectKey key, + const char* outputColor, + const char* inputColor, + const TransformedCoordsArray&, + const TextureSamplerArray& samplers) SK_OVERRIDE { + const CircleEdgeEffect& circleEffect = drawEffect.castEffect(); + const char *vsName, *fsName; + builder->addVarying(kVec4f_GrSLType, "CircleEdge", &vsName, &fsName); + + const SkString* attrName = + builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[0]); + builder->vsCodeAppendf("\t%s = %s;\n", vsName, attrName->c_str()); + + builder->fsCodeAppendf("\tfloat d = length(%s.xy);\n", fsName); + builder->fsCodeAppendf("\tfloat edgeAlpha = clamp(%s.z - d, 0.0, 1.0);\n", fsName); + if (circleEffect.isStroked()) { + builder->fsCodeAppendf("\tfloat innerAlpha = clamp(d - %s.w, 0.0, 1.0);\n", fsName); + builder->fsCodeAppend("\tedgeAlpha *= innerAlpha;\n"); + } + + builder->fsCodeAppendf("\t%s = %s;\n", outputColor, + (GrGLSLExpr4(inputColor) * GrGLSLExpr1("edgeAlpha")).c_str()); + } + + static inline EffectKey GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) { + const CircleEdgeEffect& circleEffect = drawEffect.castEffect(); + + return circleEffect.isStroked() ? 0x1 : 0x0; + } + + virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE {} + + private: + typedef GrGLVertexEffect INHERITED; + }; + + +private: + CircleEdgeEffect(bool stroke) : GrVertexEffect() { + this->addVertexAttrib(kVec4f_GrSLType); + fStroke = stroke; + } + + virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE { + const CircleEdgeEffect& cee = CastEffect(other); + return cee.fStroke == fStroke; + } + + bool fStroke; + + GR_DECLARE_EFFECT_TEST; + + typedef GrVertexEffect INHERITED; +}; + +GR_DEFINE_EFFECT_TEST(CircleEdgeEffect); + +GrEffectRef* CircleEdgeEffect::TestCreate(SkRandom* random, + GrContext* context, + const GrDrawTargetCaps&, + GrTexture* textures[]) { + return CircleEdgeEffect::Create(random->nextBool()); +} + +/////////////////////////////////////////////////////////////////////////////// + +/** + * The output of this effect is a modulation of the input color and coverage for an axis-aligned + * ellipse, specified as a 2D offset from center, and the reciprocals of the outer and inner radii, + * in both x and y directions. + * + * We are using an implicit function of x^2/a^2 + y^2/b^2 - 1 = 0. + */ + +class EllipseEdgeEffect : public GrVertexEffect { +public: + static GrEffectRef* Create(bool stroke) { + GR_CREATE_STATIC_EFFECT(gEllipseStrokeEdge, EllipseEdgeEffect, (true)); + GR_CREATE_STATIC_EFFECT(gEllipseFillEdge, EllipseEdgeEffect, (false)); + + if (stroke) { + gEllipseStrokeEdge->ref(); + return gEllipseStrokeEdge; + } else { + gEllipseFillEdge->ref(); + return gEllipseFillEdge; + } + } + + virtual void getConstantColorComponents(GrColor* color, + uint32_t* validFlags) const SK_OVERRIDE { + *validFlags = 0; + } + + virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE { + return GrTBackendEffectFactory::getInstance(); + } + + virtual ~EllipseEdgeEffect() {} + + static const char* Name() { return "EllipseEdge"; } + + inline bool isStroked() const { return fStroke; } + + class GLEffect : public GrGLVertexEffect { + public: + GLEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&) + : INHERITED (factory) {} + + virtual void emitCode(GrGLFullShaderBuilder* builder, + const GrDrawEffect& drawEffect, + EffectKey key, + const char* outputColor, + const char* inputColor, + const TransformedCoordsArray&, + const TextureSamplerArray& samplers) SK_OVERRIDE { + const EllipseEdgeEffect& ellipseEffect = drawEffect.castEffect(); + + const char *vsOffsetName, *fsOffsetName; + const char *vsRadiiName, *fsRadiiName; + + builder->addVarying(kVec2f_GrSLType, "EllipseOffsets", &vsOffsetName, &fsOffsetName); + const SkString* attr0Name = + builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[0]); + builder->vsCodeAppendf("\t%s = %s;\n", vsOffsetName, attr0Name->c_str()); + + builder->addVarying(kVec4f_GrSLType, "EllipseRadii", &vsRadiiName, &fsRadiiName); + const SkString* attr1Name = + builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[1]); + builder->vsCodeAppendf("\t%s = %s;\n", vsRadiiName, attr1Name->c_str()); + + // for outer curve + builder->fsCodeAppendf("\tvec2 scaledOffset = %s*%s.xy;\n", fsOffsetName, fsRadiiName); + builder->fsCodeAppend("\tfloat test = dot(scaledOffset, scaledOffset) - 1.0;\n"); + builder->fsCodeAppendf("\tvec2 grad = 2.0*scaledOffset*%s.xy;\n", fsRadiiName); + builder->fsCodeAppend("\tfloat grad_dot = dot(grad, grad);\n"); + // we need to clamp the length^2 of the gradiant vector to a non-zero value, because + // on the Nexus 4 the undefined result of inversesqrt(0) drops out an entire tile + // TODO: restrict this to Adreno-only + builder->fsCodeAppend("\tgrad_dot = max(grad_dot, 1.0e-4);\n"); + builder->fsCodeAppend("\tfloat invlen = inversesqrt(grad_dot);\n"); + builder->fsCodeAppend("\tfloat edgeAlpha = clamp(0.5-test*invlen, 0.0, 1.0);\n"); + + // for inner curve + if (ellipseEffect.isStroked()) { + builder->fsCodeAppendf("\tscaledOffset = %s*%s.zw;\n", fsOffsetName, fsRadiiName); + builder->fsCodeAppend("\ttest = dot(scaledOffset, scaledOffset) - 1.0;\n"); + builder->fsCodeAppendf("\tgrad = 2.0*scaledOffset*%s.zw;\n", fsRadiiName); + builder->fsCodeAppend("\tinvlen = inversesqrt(dot(grad, grad));\n"); + builder->fsCodeAppend("\tedgeAlpha *= clamp(0.5+test*invlen, 0.0, 1.0);\n"); + } + + builder->fsCodeAppendf("\t%s = %s;\n", outputColor, + (GrGLSLExpr4(inputColor) * GrGLSLExpr1("edgeAlpha")).c_str()); + } + + static inline EffectKey GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) { + const EllipseEdgeEffect& ellipseEffect = drawEffect.castEffect(); + + return ellipseEffect.isStroked() ? 0x1 : 0x0; + } + + virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE { + } + + private: + typedef GrGLVertexEffect INHERITED; + }; + +private: + EllipseEdgeEffect(bool stroke) : GrVertexEffect() { + this->addVertexAttrib(kVec2f_GrSLType); + this->addVertexAttrib(kVec4f_GrSLType); + fStroke = stroke; + } + + virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE { + const EllipseEdgeEffect& eee = CastEffect(other); + return eee.fStroke == fStroke; + } + + bool fStroke; + + GR_DECLARE_EFFECT_TEST; + + typedef GrVertexEffect INHERITED; +}; + +GR_DEFINE_EFFECT_TEST(EllipseEdgeEffect); + +GrEffectRef* EllipseEdgeEffect::TestCreate(SkRandom* random, + GrContext* context, + const GrDrawTargetCaps&, + GrTexture* textures[]) { + return EllipseEdgeEffect::Create(random->nextBool()); +} + +/////////////////////////////////////////////////////////////////////////////// + +/** + * The output of this effect is a modulation of the input color and coverage for an ellipse, + * specified as a 2D offset from center for both the outer and inner paths (if stroked). The + * implict equation used is for a unit circle (x^2 + y^2 - 1 = 0) and the edge corrected by + * using differentials. + * + * The result is device-independent and can be used with any affine matrix. + */ + +class DIEllipseEdgeEffect : public GrVertexEffect { +public: + enum Mode { kStroke = 0, kHairline, kFill }; + + static GrEffectRef* Create(Mode mode) { + GR_CREATE_STATIC_EFFECT(gEllipseStrokeEdge, DIEllipseEdgeEffect, (kStroke)); + GR_CREATE_STATIC_EFFECT(gEllipseHairlineEdge, DIEllipseEdgeEffect, (kHairline)); + GR_CREATE_STATIC_EFFECT(gEllipseFillEdge, DIEllipseEdgeEffect, (kFill)); + + if (kStroke == mode) { + gEllipseStrokeEdge->ref(); + return gEllipseStrokeEdge; + } else if (kHairline == mode) { + gEllipseHairlineEdge->ref(); + return gEllipseHairlineEdge; + } else { + gEllipseFillEdge->ref(); + return gEllipseFillEdge; + } + } + + virtual void getConstantColorComponents(GrColor* color, + uint32_t* validFlags) const SK_OVERRIDE { + *validFlags = 0; + } + + virtual const GrBackendEffectFactory& getFactory() const SK_OVERRIDE { + return GrTBackendEffectFactory::getInstance(); + } + + virtual ~DIEllipseEdgeEffect() {} + + static const char* Name() { return "DIEllipseEdge"; } + + inline Mode getMode() const { return fMode; } + + class GLEffect : public GrGLVertexEffect { + public: + GLEffect(const GrBackendEffectFactory& factory, const GrDrawEffect&) + : INHERITED (factory) {} + + virtual void emitCode(GrGLFullShaderBuilder* builder, + const GrDrawEffect& drawEffect, + EffectKey key, + const char* outputColor, + const char* inputColor, + const TransformedCoordsArray&, + const TextureSamplerArray& samplers) SK_OVERRIDE { + const DIEllipseEdgeEffect& ellipseEffect = drawEffect.castEffect(); + + SkAssertResult(builder->enableFeature( + GrGLShaderBuilder::kStandardDerivatives_GLSLFeature)); + + const char *vsOffsetName0, *fsOffsetName0; + builder->addVarying(kVec2f_GrSLType, "EllipseOffsets0", + &vsOffsetName0, &fsOffsetName0); + const SkString* attr0Name = + builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[0]); + builder->vsCodeAppendf("\t%s = %s;\n", vsOffsetName0, attr0Name->c_str()); + const char *vsOffsetName1, *fsOffsetName1; + builder->addVarying(kVec2f_GrSLType, "EllipseOffsets1", + &vsOffsetName1, &fsOffsetName1); + const SkString* attr1Name = + builder->getEffectAttributeName(drawEffect.getVertexAttribIndices()[1]); + builder->vsCodeAppendf("\t%s = %s;\n", vsOffsetName1, attr1Name->c_str()); + + // for outer curve + builder->fsCodeAppendf("\tvec2 scaledOffset = %s.xy;\n", fsOffsetName0); + builder->fsCodeAppend("\tfloat test = dot(scaledOffset, scaledOffset) - 1.0;\n"); + builder->fsCodeAppendf("\tvec2 duvdx = dFdx(%s);\n", fsOffsetName0); + builder->fsCodeAppendf("\tvec2 duvdy = dFdy(%s);\n", fsOffsetName0); + builder->fsCodeAppendf("\tvec2 grad = vec2(2.0*%s.x*duvdx.x + 2.0*%s.y*duvdx.y,\n" + "\t 2.0*%s.x*duvdy.x + 2.0*%s.y*duvdy.y);\n", + fsOffsetName0, fsOffsetName0, fsOffsetName0, fsOffsetName0); + + builder->fsCodeAppend("\tfloat grad_dot = dot(grad, grad);\n"); + // we need to clamp the length^2 of the gradiant vector to a non-zero value, because + // on the Nexus 4 the undefined result of inversesqrt(0) drops out an entire tile + // TODO: restrict this to Adreno-only + builder->fsCodeAppend("\tgrad_dot = max(grad_dot, 1.0e-4);\n"); + builder->fsCodeAppend("\tfloat invlen = inversesqrt(grad_dot);\n"); + if (kHairline == ellipseEffect.getMode()) { + // can probably do this with one step + builder->fsCodeAppend("\tfloat edgeAlpha = clamp(1.0-test*invlen, 0.0, 1.0);\n"); + builder->fsCodeAppend("\tedgeAlpha *= clamp(1.0+test*invlen, 0.0, 1.0);\n"); + } else { + builder->fsCodeAppend("\tfloat edgeAlpha = clamp(0.5-test*invlen, 0.0, 1.0);\n"); + } + + // for inner curve + if (kStroke == ellipseEffect.getMode()) { + builder->fsCodeAppendf("\tscaledOffset = %s.xy;\n", fsOffsetName1); + builder->fsCodeAppend("\ttest = dot(scaledOffset, scaledOffset) - 1.0;\n"); + builder->fsCodeAppendf("\tduvdx = dFdx(%s);\n", fsOffsetName1); + builder->fsCodeAppendf("\tduvdy = dFdy(%s);\n", fsOffsetName1); + builder->fsCodeAppendf("\tgrad = vec2(2.0*%s.x*duvdx.x + 2.0*%s.y*duvdx.y,\n" + "\t 2.0*%s.x*duvdy.x + 2.0*%s.y*duvdy.y);\n", + fsOffsetName1, fsOffsetName1, fsOffsetName1, fsOffsetName1); + builder->fsCodeAppend("\tinvlen = inversesqrt(dot(grad, grad));\n"); + builder->fsCodeAppend("\tedgeAlpha *= clamp(0.5+test*invlen, 0.0, 1.0);\n"); + } + + builder->fsCodeAppendf("\t%s = %s;\n", outputColor, + (GrGLSLExpr4(inputColor) * GrGLSLExpr1("edgeAlpha")).c_str()); + } + + static inline EffectKey GenKey(const GrDrawEffect& drawEffect, const GrGLCaps&) { + const DIEllipseEdgeEffect& ellipseEffect = drawEffect.castEffect(); + + return ellipseEffect.getMode(); + } + + virtual void setData(const GrGLUniformManager&, const GrDrawEffect&) SK_OVERRIDE { + } + + private: + typedef GrGLVertexEffect INHERITED; + }; + +private: + DIEllipseEdgeEffect(Mode mode) : GrVertexEffect() { + this->addVertexAttrib(kVec2f_GrSLType); + this->addVertexAttrib(kVec2f_GrSLType); + fMode = mode; + } + + virtual bool onIsEqual(const GrEffect& other) const SK_OVERRIDE { + const DIEllipseEdgeEffect& eee = CastEffect(other); + return eee.fMode == fMode; + } + + Mode fMode; + + GR_DECLARE_EFFECT_TEST; + + typedef GrVertexEffect INHERITED; +}; + +GR_DEFINE_EFFECT_TEST(DIEllipseEdgeEffect); + +GrEffectRef* DIEllipseEdgeEffect::TestCreate(SkRandom* random, + GrContext* context, + const GrDrawTargetCaps&, + GrTexture* textures[]) { + return DIEllipseEdgeEffect::Create((Mode)(random->nextRangeU(0,2))); +} + +/////////////////////////////////////////////////////////////////////////////// + +void GrOvalRenderer::reset() { + SkSafeSetNull(fRRectIndexBuffer); +} + +bool GrOvalRenderer::drawOval(GrDrawTarget* target, const GrContext* context, bool useAA, + const SkRect& oval, const SkStrokeRec& stroke) +{ + bool useCoverageAA = useAA && + !target->getDrawState().getRenderTarget()->isMultisampled() && + !target->shouldDisableCoverageAAForBlend(); + + if (!useCoverageAA) { + return false; + } + + const SkMatrix& vm = context->getMatrix(); + + // we can draw circles + if (SkScalarNearlyEqual(oval.width(), oval.height()) + && circle_stays_circle(vm)) { + this->drawCircle(target, useCoverageAA, oval, stroke); + // if we have shader derivative support, render as device-independent + } else if (target->caps()->shaderDerivativeSupport()) { + return this->drawDIEllipse(target, useCoverageAA, oval, stroke); + // otherwise axis-aligned ellipses only + } else if (vm.rectStaysRect()) { + return this->drawEllipse(target, useCoverageAA, oval, stroke); + } else { + return false; + } + + return true; +} + +/////////////////////////////////////////////////////////////////////////////// + +// position + edge +extern const GrVertexAttrib gCircleVertexAttribs[] = { + {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding}, + {kVec4f_GrVertexAttribType, sizeof(GrPoint), kEffect_GrVertexAttribBinding} +}; + +void GrOvalRenderer::drawCircle(GrDrawTarget* target, + bool useCoverageAA, + const SkRect& circle, + const SkStrokeRec& stroke) +{ + GrDrawState* drawState = target->drawState(); + + const SkMatrix& vm = drawState->getViewMatrix(); + GrPoint center = GrPoint::Make(circle.centerX(), circle.centerY()); + vm.mapPoints(¢er, 1); + SkScalar radius = vm.mapRadius(SkScalarHalf(circle.width())); + SkScalar strokeWidth = vm.mapRadius(stroke.getWidth()); + + GrDrawState::AutoViewMatrixRestore avmr; + if (!avmr.setIdentity(drawState)) { + return; + } + + drawState->setVertexAttribs(SK_ARRAY_COUNT(gCircleVertexAttribs)); + SkASSERT(sizeof(CircleVertex) == drawState->getVertexSize()); + + GrDrawTarget::AutoReleaseGeometry geo(target, 4, 0); + if (!geo.succeeded()) { + GrPrintf("Failed to get space for vertices!\n"); + return; + } + + CircleVertex* verts = reinterpret_cast(geo.vertices()); + + SkStrokeRec::Style style = stroke.getStyle(); + bool isStroked = (SkStrokeRec::kStroke_Style == style || SkStrokeRec::kHairline_Style == style); + + SkScalar innerRadius = 0.0f; + SkScalar outerRadius = radius; + SkScalar halfWidth = 0; + if (style != SkStrokeRec::kFill_Style) { + if (SkScalarNearlyZero(strokeWidth)) { + halfWidth = SK_ScalarHalf; + } else { + halfWidth = SkScalarHalf(strokeWidth); + } + + outerRadius += halfWidth; + if (isStroked) { + innerRadius = radius - halfWidth; + } + } + + GrEffectRef* effect = CircleEdgeEffect::Create(isStroked && innerRadius > 0); + static const int kCircleEdgeAttrIndex = 1; + drawState->addCoverageEffect(effect, kCircleEdgeAttrIndex)->unref(); + + // The radii are outset for two reasons. First, it allows the shader to simply perform + // clamp(distance-to-center - radius, 0, 1). Second, the outer radius is used to compute the + // verts of the bounding box that is rendered and the outset ensures the box will cover all + // pixels partially covered by the circle. + outerRadius += SK_ScalarHalf; + innerRadius -= SK_ScalarHalf; + + SkRect bounds = SkRect::MakeLTRB( + center.fX - outerRadius, + center.fY - outerRadius, + center.fX + outerRadius, + center.fY + outerRadius + ); + + verts[0].fPos = SkPoint::Make(bounds.fLeft, bounds.fTop); + verts[0].fOffset = SkPoint::Make(-outerRadius, -outerRadius); + verts[0].fOuterRadius = outerRadius; + verts[0].fInnerRadius = innerRadius; + + verts[1].fPos = SkPoint::Make(bounds.fRight, bounds.fTop); + verts[1].fOffset = SkPoint::Make(outerRadius, -outerRadius); + verts[1].fOuterRadius = outerRadius; + verts[1].fInnerRadius = innerRadius; + + verts[2].fPos = SkPoint::Make(bounds.fLeft, bounds.fBottom); + verts[2].fOffset = SkPoint::Make(-outerRadius, outerRadius); + verts[2].fOuterRadius = outerRadius; + verts[2].fInnerRadius = innerRadius; + + verts[3].fPos = SkPoint::Make(bounds.fRight, bounds.fBottom); + verts[3].fOffset = SkPoint::Make(outerRadius, outerRadius); + verts[3].fOuterRadius = outerRadius; + verts[3].fInnerRadius = innerRadius; + + target->drawNonIndexed(kTriangleStrip_GrPrimitiveType, 0, 4, &bounds); +} + +/////////////////////////////////////////////////////////////////////////////// + +// position + offset + 1/radii +extern const GrVertexAttrib gEllipseVertexAttribs[] = { + {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding}, + {kVec2f_GrVertexAttribType, sizeof(GrPoint), kEffect_GrVertexAttribBinding}, + {kVec4f_GrVertexAttribType, 2*sizeof(GrPoint), kEffect_GrVertexAttribBinding} +}; + +// position + offsets +extern const GrVertexAttrib gDIEllipseVertexAttribs[] = { + {kVec2f_GrVertexAttribType, 0, kPosition_GrVertexAttribBinding}, + {kVec2f_GrVertexAttribType, sizeof(GrPoint), kEffect_GrVertexAttribBinding}, + {kVec2f_GrVertexAttribType, 2*sizeof(GrPoint), kEffect_GrVertexAttribBinding}, +}; + +bool GrOvalRenderer::drawEllipse(GrDrawTarget* target, + bool useCoverageAA, + const SkRect& ellipse, + const SkStrokeRec& stroke) +{ + GrDrawState* drawState = target->drawState(); +#ifdef SK_DEBUG + { + // we should have checked for this previously + bool isAxisAlignedEllipse = drawState->getViewMatrix().rectStaysRect(); + SkASSERT(useCoverageAA && isAxisAlignedEllipse); + } +#endif + + // do any matrix crunching before we reset the draw state for device coords + const SkMatrix& vm = drawState->getViewMatrix(); + GrPoint center = GrPoint::Make(ellipse.centerX(), ellipse.centerY()); + vm.mapPoints(¢er, 1); + SkScalar ellipseXRadius = SkScalarHalf(ellipse.width()); + SkScalar ellipseYRadius = SkScalarHalf(ellipse.height()); + SkScalar xRadius = SkScalarAbs(vm[SkMatrix::kMScaleX]*ellipseXRadius + + vm[SkMatrix::kMSkewY]*ellipseYRadius); + SkScalar yRadius = SkScalarAbs(vm[SkMatrix::kMSkewX]*ellipseXRadius + + vm[SkMatrix::kMScaleY]*ellipseYRadius); + + // do (potentially) anisotropic mapping of stroke + SkVector scaledStroke; + SkScalar strokeWidth = stroke.getWidth(); + scaledStroke.fX = SkScalarAbs(strokeWidth*(vm[SkMatrix::kMScaleX] + vm[SkMatrix::kMSkewY])); + scaledStroke.fY = SkScalarAbs(strokeWidth*(vm[SkMatrix::kMSkewX] + vm[SkMatrix::kMScaleY])); + + SkStrokeRec::Style style = stroke.getStyle(); + bool isStroked = (SkStrokeRec::kStroke_Style == style || SkStrokeRec::kHairline_Style == style); + + SkScalar innerXRadius = 0; + SkScalar innerYRadius = 0; + if (SkStrokeRec::kFill_Style != style) { + if (SkScalarNearlyZero(scaledStroke.length())) { + scaledStroke.set(SK_ScalarHalf, SK_ScalarHalf); + } else { + scaledStroke.scale(SK_ScalarHalf); + } + + // we only handle thick strokes for near-circular ellipses + if (scaledStroke.length() > SK_ScalarHalf && + (SK_ScalarHalf*xRadius > yRadius || SK_ScalarHalf*yRadius > xRadius)) { + return false; + } + + // we don't handle it if curvature of the stroke is less than curvature of the ellipse + if (scaledStroke.fX*(yRadius*yRadius) < (scaledStroke.fY*scaledStroke.fY)*xRadius || + scaledStroke.fY*(xRadius*xRadius) < (scaledStroke.fX*scaledStroke.fX)*yRadius) { + return false; + } + + // this is legit only if scale & translation (which should be the case at the moment) + if (isStroked) { + innerXRadius = xRadius - scaledStroke.fX; + innerYRadius = yRadius - scaledStroke.fY; + } + + xRadius += scaledStroke.fX; + yRadius += scaledStroke.fY; + } + + GrDrawState::AutoViewMatrixRestore avmr; + if (!avmr.setIdentity(drawState)) { + return false; + } + + drawState->setVertexAttribs(SK_ARRAY_COUNT(gEllipseVertexAttribs)); + SkASSERT(sizeof(EllipseVertex) == drawState->getVertexSize()); + + GrDrawTarget::AutoReleaseGeometry geo(target, 4, 0); + if (!geo.succeeded()) { + GrPrintf("Failed to get space for vertices!\n"); + return false; + } + + EllipseVertex* verts = reinterpret_cast(geo.vertices()); + + GrEffectRef* effect = EllipseEdgeEffect::Create(isStroked && + innerXRadius > 0 && innerYRadius > 0); + + static const int kEllipseCenterAttrIndex = 1; + static const int kEllipseEdgeAttrIndex = 2; + drawState->addCoverageEffect(effect, kEllipseCenterAttrIndex, kEllipseEdgeAttrIndex)->unref(); + + // Compute the reciprocals of the radii here to save time in the shader + SkScalar xRadRecip = SkScalarInvert(xRadius); + SkScalar yRadRecip = SkScalarInvert(yRadius); + SkScalar xInnerRadRecip = SkScalarInvert(innerXRadius); + SkScalar yInnerRadRecip = SkScalarInvert(innerYRadius); + + // We've extended the outer x radius out half a pixel to antialias. + // This will also expand the rect so all the pixels will be captured. + // TODO: Consider if we should use sqrt(2)/2 instead + xRadius += SK_ScalarHalf; + yRadius += SK_ScalarHalf; + + SkRect bounds = SkRect::MakeLTRB( + center.fX - xRadius, + center.fY - yRadius, + center.fX + xRadius, + center.fY + yRadius + ); + + verts[0].fPos = SkPoint::Make(bounds.fLeft, bounds.fTop); + verts[0].fOffset = SkPoint::Make(-xRadius, -yRadius); + verts[0].fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip); + verts[0].fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip); + + verts[1].fPos = SkPoint::Make(bounds.fRight, bounds.fTop); + verts[1].fOffset = SkPoint::Make(xRadius, -yRadius); + verts[1].fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip); + verts[1].fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip); + + verts[2].fPos = SkPoint::Make(bounds.fLeft, bounds.fBottom); + verts[2].fOffset = SkPoint::Make(-xRadius, yRadius); + verts[2].fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip); + verts[2].fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip); + + verts[3].fPos = SkPoint::Make(bounds.fRight, bounds.fBottom); + verts[3].fOffset = SkPoint::Make(xRadius, yRadius); + verts[3].fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip); + verts[3].fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip); + + target->drawNonIndexed(kTriangleStrip_GrPrimitiveType, 0, 4, &bounds); + + return true; +} + +bool GrOvalRenderer::drawDIEllipse(GrDrawTarget* target, + bool useCoverageAA, + const SkRect& ellipse, + const SkStrokeRec& stroke) +{ + GrDrawState* drawState = target->drawState(); + const SkMatrix& vm = drawState->getViewMatrix(); + + GrPoint center = GrPoint::Make(ellipse.centerX(), ellipse.centerY()); + SkScalar xRadius = SkScalarHalf(ellipse.width()); + SkScalar yRadius = SkScalarHalf(ellipse.height()); + + SkStrokeRec::Style style = stroke.getStyle(); + DIEllipseEdgeEffect::Mode mode = (SkStrokeRec::kStroke_Style == style) ? + DIEllipseEdgeEffect::kStroke : + (SkStrokeRec::kHairline_Style == style) ? + DIEllipseEdgeEffect::kHairline : DIEllipseEdgeEffect::kFill; + + SkScalar innerXRadius = 0; + SkScalar innerYRadius = 0; + if (SkStrokeRec::kFill_Style != style && SkStrokeRec::kHairline_Style != style) { + SkScalar strokeWidth = stroke.getWidth(); + + if (SkScalarNearlyZero(strokeWidth)) { + strokeWidth = SK_ScalarHalf; + } else { + strokeWidth *= SK_ScalarHalf; + } + + // we only handle thick strokes for near-circular ellipses + if (strokeWidth > SK_ScalarHalf && + (SK_ScalarHalf*xRadius > yRadius || SK_ScalarHalf*yRadius > xRadius)) { + return false; + } + + // we don't handle it if curvature of the stroke is less than curvature of the ellipse + if (strokeWidth*(yRadius*yRadius) < (strokeWidth*strokeWidth)*xRadius || + strokeWidth*(xRadius*xRadius) < (strokeWidth*strokeWidth)*yRadius) { + return false; + } + + // set inner radius (if needed) + if (SkStrokeRec::kStroke_Style == style) { + innerXRadius = xRadius - strokeWidth; + innerYRadius = yRadius - strokeWidth; + } + + xRadius += strokeWidth; + yRadius += strokeWidth; + } + if (DIEllipseEdgeEffect::kStroke == mode) { + mode = (innerXRadius > 0 && innerYRadius > 0) ? DIEllipseEdgeEffect::kStroke : + DIEllipseEdgeEffect::kFill; + } + SkScalar innerRatioX = SkScalarDiv(xRadius, innerXRadius); + SkScalar innerRatioY = SkScalarDiv(yRadius, innerYRadius); + + drawState->setVertexAttribs(SK_ARRAY_COUNT(gDIEllipseVertexAttribs)); + SkASSERT(sizeof(DIEllipseVertex) == drawState->getVertexSize()); + + GrDrawTarget::AutoReleaseGeometry geo(target, 4, 0); + if (!geo.succeeded()) { + GrPrintf("Failed to get space for vertices!\n"); + return false; + } + + DIEllipseVertex* verts = reinterpret_cast(geo.vertices()); + + GrEffectRef* effect = DIEllipseEdgeEffect::Create(mode); + + static const int kEllipseOuterOffsetAttrIndex = 1; + static const int kEllipseInnerOffsetAttrIndex = 2; + drawState->addCoverageEffect(effect, kEllipseOuterOffsetAttrIndex, + kEllipseInnerOffsetAttrIndex)->unref(); + + // This expands the outer rect so that after CTM we end up with a half-pixel border + SkScalar a = vm[SkMatrix::kMScaleX]; + SkScalar b = vm[SkMatrix::kMSkewX]; + SkScalar c = vm[SkMatrix::kMSkewY]; + SkScalar d = vm[SkMatrix::kMScaleY]; + SkScalar geoDx = SkScalarDiv(SK_ScalarHalf, SkScalarSqrt(a*a + c*c)); + SkScalar geoDy = SkScalarDiv(SK_ScalarHalf, SkScalarSqrt(b*b + d*d)); + // This adjusts the "radius" to include the half-pixel border + SkScalar offsetDx = SkScalarDiv(geoDx, xRadius); + SkScalar offsetDy = SkScalarDiv(geoDy, yRadius); + + SkRect bounds = SkRect::MakeLTRB( + center.fX - xRadius - geoDx, + center.fY - yRadius - geoDy, + center.fX + xRadius + geoDx, + center.fY + yRadius + geoDy + ); + + verts[0].fPos = SkPoint::Make(bounds.fLeft, bounds.fTop); + verts[0].fOuterOffset = SkPoint::Make(-1.0f - offsetDx, -1.0f - offsetDy); + verts[0].fInnerOffset = SkPoint::Make(-innerRatioX - offsetDx, -innerRatioY - offsetDy); + + verts[1].fPos = SkPoint::Make(bounds.fRight, bounds.fTop); + verts[1].fOuterOffset = SkPoint::Make(1.0f + offsetDx, -1.0f - offsetDy); + verts[1].fInnerOffset = SkPoint::Make(innerRatioX + offsetDx, -innerRatioY - offsetDy); + + verts[2].fPos = SkPoint::Make(bounds.fLeft, bounds.fBottom); + verts[2].fOuterOffset = SkPoint::Make(-1.0f - offsetDx, 1.0f + offsetDy); + verts[2].fInnerOffset = SkPoint::Make(-innerRatioX - offsetDx, innerRatioY + offsetDy); + + verts[3].fPos = SkPoint::Make(bounds.fRight, bounds.fBottom); + verts[3].fOuterOffset = SkPoint::Make(1.0f + offsetDx, 1.0f + offsetDy); + verts[3].fInnerOffset = SkPoint::Make(innerRatioX + offsetDx, innerRatioY + offsetDy); + + target->drawNonIndexed(kTriangleStrip_GrPrimitiveType, 0, 4, &bounds); + + return true; +} + +/////////////////////////////////////////////////////////////////////////////// + +static const uint16_t gRRectIndices[] = { + // corners + 0, 1, 5, 0, 5, 4, + 2, 3, 7, 2, 7, 6, + 8, 9, 13, 8, 13, 12, + 10, 11, 15, 10, 15, 14, + + // edges + 1, 2, 6, 1, 6, 5, + 4, 5, 9, 4, 9, 8, + 6, 7, 11, 6, 11, 10, + 9, 10, 14, 9, 14, 13, + + // center + // we place this at the end so that we can ignore these indices when rendering stroke-only + 5, 6, 10, 5, 10, 9 +}; + + +GrIndexBuffer* GrOvalRenderer::rRectIndexBuffer(GrGpu* gpu) { + if (NULL == fRRectIndexBuffer) { + fRRectIndexBuffer = + gpu->createIndexBuffer(sizeof(gRRectIndices), false); + if (NULL != fRRectIndexBuffer) { +#ifdef SK_DEBUG + bool updated = +#endif + fRRectIndexBuffer->updateData(gRRectIndices, + sizeof(gRRectIndices)); + GR_DEBUGASSERT(updated); + } + } + return fRRectIndexBuffer; +} + +bool GrOvalRenderer::drawSimpleRRect(GrDrawTarget* target, GrContext* context, bool useAA, + const SkRRect& rrect, const SkStrokeRec& stroke) +{ + bool useCoverageAA = useAA && + !target->getDrawState().getRenderTarget()->isMultisampled() && + !target->shouldDisableCoverageAAForBlend(); + + // only anti-aliased rrects for now + if (!useCoverageAA) { + return false; + } + + const SkMatrix& vm = context->getMatrix(); +#ifdef SK_DEBUG + { + // we should have checked for this previously + SkASSERT(useCoverageAA && vm.rectStaysRect() && rrect.isSimple()); + } +#endif + + // do any matrix crunching before we reset the draw state for device coords + const SkRect& rrectBounds = rrect.getBounds(); + SkRect bounds; + vm.mapRect(&bounds, rrectBounds); + + SkVector radii = rrect.getSimpleRadii(); + SkScalar xRadius = SkScalarAbs(vm[SkMatrix::kMScaleX]*radii.fX + + vm[SkMatrix::kMSkewY]*radii.fY); + SkScalar yRadius = SkScalarAbs(vm[SkMatrix::kMSkewX]*radii.fX + + vm[SkMatrix::kMScaleY]*radii.fY); + + // if hairline stroke is greater than radius, we don't handle that right now + SkStrokeRec::Style style = stroke.getStyle(); + if (SkStrokeRec::kHairline_Style == style && + (SK_ScalarHalf > xRadius || SK_ScalarHalf > yRadius)) { + return false; + } + + // do (potentially) anisotropic mapping of stroke + SkVector scaledStroke; + SkScalar strokeWidth = stroke.getWidth(); + scaledStroke.fX = SkScalarAbs(strokeWidth*(vm[SkMatrix::kMScaleX] + vm[SkMatrix::kMSkewY])); + scaledStroke.fY = SkScalarAbs(strokeWidth*(vm[SkMatrix::kMSkewX] + vm[SkMatrix::kMScaleY])); + + // if half of strokewidth is greater than radius, we don't handle that right now + if (SK_ScalarHalf*scaledStroke.fX > xRadius || SK_ScalarHalf*scaledStroke.fY > yRadius) { + return false; + } + + // reset to device coordinates + GrDrawState* drawState = target->drawState(); + GrDrawState::AutoViewMatrixRestore avmr; + if (!avmr.setIdentity(drawState)) { + return false; + } + + bool isStroked = (SkStrokeRec::kStroke_Style == style || SkStrokeRec::kHairline_Style == style); + + GrIndexBuffer* indexBuffer = this->rRectIndexBuffer(context->getGpu()); + if (NULL == indexBuffer) { + GrPrintf("Failed to create index buffer!\n"); + return false; + } + + // if the corners are circles, use the circle renderer + if ((!isStroked || scaledStroke.fX == scaledStroke.fY) && xRadius == yRadius) { + drawState->setVertexAttribs(SK_ARRAY_COUNT(gCircleVertexAttribs)); + SkASSERT(sizeof(CircleVertex) == drawState->getVertexSize()); + + GrDrawTarget::AutoReleaseGeometry geo(target, 16, 0); + if (!geo.succeeded()) { + GrPrintf("Failed to get space for vertices!\n"); + return false; + } + CircleVertex* verts = reinterpret_cast(geo.vertices()); + + SkScalar innerRadius = 0.0f; + SkScalar outerRadius = xRadius; + SkScalar halfWidth = 0; + if (style != SkStrokeRec::kFill_Style) { + if (SkScalarNearlyZero(scaledStroke.fX)) { + halfWidth = SK_ScalarHalf; + } else { + halfWidth = SkScalarHalf(scaledStroke.fX); + } + + if (isStroked) { + innerRadius = xRadius - halfWidth; + } + outerRadius += halfWidth; + bounds.outset(halfWidth, halfWidth); + } + + isStroked = (isStroked && innerRadius >= 0); + + GrEffectRef* effect = CircleEdgeEffect::Create(isStroked); + static const int kCircleEdgeAttrIndex = 1; + drawState->addCoverageEffect(effect, kCircleEdgeAttrIndex)->unref(); + + // The radii are outset for two reasons. First, it allows the shader to simply perform + // clamp(distance-to-center - radius, 0, 1). Second, the outer radius is used to compute the + // verts of the bounding box that is rendered and the outset ensures the box will cover all + // pixels partially covered by the circle. + outerRadius += SK_ScalarHalf; + innerRadius -= SK_ScalarHalf; + + // Expand the rect so all the pixels will be captured. + bounds.outset(SK_ScalarHalf, SK_ScalarHalf); + + SkScalar yCoords[4] = { + bounds.fTop, + bounds.fTop + outerRadius, + bounds.fBottom - outerRadius, + bounds.fBottom + }; + SkScalar yOuterRadii[4] = { + -outerRadius, + 0, + 0, + outerRadius + }; + for (int i = 0; i < 4; ++i) { + verts->fPos = SkPoint::Make(bounds.fLeft, yCoords[i]); + verts->fOffset = SkPoint::Make(-outerRadius, yOuterRadii[i]); + verts->fOuterRadius = outerRadius; + verts->fInnerRadius = innerRadius; + verts++; + + verts->fPos = SkPoint::Make(bounds.fLeft + outerRadius, yCoords[i]); + verts->fOffset = SkPoint::Make(0, yOuterRadii[i]); + verts->fOuterRadius = outerRadius; + verts->fInnerRadius = innerRadius; + verts++; + + verts->fPos = SkPoint::Make(bounds.fRight - outerRadius, yCoords[i]); + verts->fOffset = SkPoint::Make(0, yOuterRadii[i]); + verts->fOuterRadius = outerRadius; + verts->fInnerRadius = innerRadius; + verts++; + + verts->fPos = SkPoint::Make(bounds.fRight, yCoords[i]); + verts->fOffset = SkPoint::Make(outerRadius, yOuterRadii[i]); + verts->fOuterRadius = outerRadius; + verts->fInnerRadius = innerRadius; + verts++; + } + + // drop out the middle quad if we're stroked + int indexCnt = isStroked ? GR_ARRAY_COUNT(gRRectIndices)-6 : GR_ARRAY_COUNT(gRRectIndices); + target->setIndexSourceToBuffer(indexBuffer); + target->drawIndexed(kTriangles_GrPrimitiveType, 0, 0, 16, indexCnt, &bounds); + + // otherwise we use the ellipse renderer + } else { + drawState->setVertexAttribs(SK_ARRAY_COUNT(gEllipseVertexAttribs)); + SkASSERT(sizeof(EllipseVertex) == drawState->getVertexSize()); + + SkScalar innerXRadius = 0.0f; + SkScalar innerYRadius = 0.0f; + if (SkStrokeRec::kFill_Style != style) { + if (SkScalarNearlyZero(scaledStroke.length())) { + scaledStroke.set(SK_ScalarHalf, SK_ScalarHalf); + } else { + scaledStroke.scale(SK_ScalarHalf); + } + + // we only handle thick strokes for near-circular ellipses + if (scaledStroke.length() > SK_ScalarHalf && + (SK_ScalarHalf*xRadius > yRadius || SK_ScalarHalf*yRadius > xRadius)) { + return false; + } + + // we don't handle it if curvature of the stroke is less than curvature of the ellipse + if (scaledStroke.fX*(yRadius*yRadius) < (scaledStroke.fY*scaledStroke.fY)*xRadius || + scaledStroke.fY*(xRadius*xRadius) < (scaledStroke.fX*scaledStroke.fX)*yRadius) { + return false; + } + + // this is legit only if scale & translation (which should be the case at the moment) + if (isStroked) { + innerXRadius = xRadius - scaledStroke.fX; + innerYRadius = yRadius - scaledStroke.fY; + } + + xRadius += scaledStroke.fX; + yRadius += scaledStroke.fY; + bounds.outset(scaledStroke.fX, scaledStroke.fY); + } + + isStroked = (isStroked && innerXRadius >= 0 && innerYRadius >= 0); + + GrDrawTarget::AutoReleaseGeometry geo(target, 16, 0); + if (!geo.succeeded()) { + GrPrintf("Failed to get space for vertices!\n"); + return false; + } + EllipseVertex* verts = reinterpret_cast(geo.vertices()); + + GrEffectRef* effect = EllipseEdgeEffect::Create(isStroked); + static const int kEllipseOffsetAttrIndex = 1; + static const int kEllipseRadiiAttrIndex = 2; + drawState->addCoverageEffect(effect, + kEllipseOffsetAttrIndex, kEllipseRadiiAttrIndex)->unref(); + + // Compute the reciprocals of the radii here to save time in the shader + SkScalar xRadRecip = SkScalarInvert(xRadius); + SkScalar yRadRecip = SkScalarInvert(yRadius); + SkScalar xInnerRadRecip = SkScalarInvert(innerXRadius); + SkScalar yInnerRadRecip = SkScalarInvert(innerYRadius); + + // Extend the radii out half a pixel to antialias. + SkScalar xOuterRadius = xRadius + SK_ScalarHalf; + SkScalar yOuterRadius = yRadius + SK_ScalarHalf; + + // Expand the rect so all the pixels will be captured. + bounds.outset(SK_ScalarHalf, SK_ScalarHalf); + + SkScalar yCoords[4] = { + bounds.fTop, + bounds.fTop + yOuterRadius, + bounds.fBottom - yOuterRadius, + bounds.fBottom + }; + SkScalar yOuterOffsets[4] = { + yOuterRadius, + SK_ScalarNearlyZero, // we're using inversesqrt() in the shader, so can't be exactly 0 + SK_ScalarNearlyZero, + yOuterRadius + }; + + for (int i = 0; i < 4; ++i) { + verts->fPos = SkPoint::Make(bounds.fLeft, yCoords[i]); + verts->fOffset = SkPoint::Make(xOuterRadius, yOuterOffsets[i]); + verts->fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip); + verts->fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip); + verts++; + + verts->fPos = SkPoint::Make(bounds.fLeft + xOuterRadius, yCoords[i]); + verts->fOffset = SkPoint::Make(SK_ScalarNearlyZero, yOuterOffsets[i]); + verts->fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip); + verts->fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip); + verts++; + + verts->fPos = SkPoint::Make(bounds.fRight - xOuterRadius, yCoords[i]); + verts->fOffset = SkPoint::Make(SK_ScalarNearlyZero, yOuterOffsets[i]); + verts->fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip); + verts->fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip); + verts++; + + verts->fPos = SkPoint::Make(bounds.fRight, yCoords[i]); + verts->fOffset = SkPoint::Make(xOuterRadius, yOuterOffsets[i]); + verts->fOuterRadii = SkPoint::Make(xRadRecip, yRadRecip); + verts->fInnerRadii = SkPoint::Make(xInnerRadRecip, yInnerRadRecip); + verts++; + } + + // drop out the middle quad if we're stroked + int indexCnt = isStroked ? GR_ARRAY_COUNT(gRRectIndices)-6 : GR_ARRAY_COUNT(gRRectIndices); + target->setIndexSourceToBuffer(indexBuffer); + target->drawIndexed(kTriangles_GrPrimitiveType, 0, 0, 16, indexCnt, &bounds); + } + + return true; +}