OLD | NEW |
(Empty) | |
| 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 "GrEllipseEdgeEffect.h" |
| 9 #include "gl/GrGLEffect.h" |
| 10 #include "gl/GrGLEffectMatrix.h" |
| 11 #include "gl/GrGLSL.h" |
| 12 #include "gl/GrGLTexture.h" |
| 13 #include "GrTBackendEffectFactory.h" |
| 14 #include "GrTexture.h" |
| 15 |
| 16 #define ELLIPSE_EDGE_ATTR0 "aEllipseEdge" |
| 17 |
| 18 class GrGLEllipseEdgeEffect : public GrGLEffect { |
| 19 public: |
| 20 GrGLEllipseEdgeEffect(const GrBackendEffectFactory& factory, const GrEffectR
ef&) |
| 21 : INHERITED (factory) {} |
| 22 |
| 23 virtual void emitCode(GrGLShaderBuilder* builder, |
| 24 const GrEffectStage&, |
| 25 EffectKey key, |
| 26 const char* vertexCoords, |
| 27 const char* outputColor, |
| 28 const char* inputColor, |
| 29 const TextureSamplerArray& samplers) SK_OVERRIDE { |
| 30 const char *vsName, *fsName; |
| 31 builder->addVarying(kVec4f_GrSLType, "EllipseEdge", &vsName, &fsName); |
| 32 builder->addAttribute(kVec4f_GrSLType, ELLIPSE_EDGE_ATTR0); |
| 33 |
| 34 builder->fVSCode.appendf("\t%s = " ELLIPSE_EDGE_ATTR0 ";\n", vsName); |
| 35 |
| 36 builder->fFSCode.append("\tfloat edgeAlpha;\n"); |
| 37 // translate to origin |
| 38 builder->fFSCode.appendf("\tvec2 offset = (%s.xy - %s.xy);\n", builder->
fragmentPosition(), fsName); |
| 39 // scale y by xRadius/yRadius |
| 40 builder->fFSCode.appendf("\toffset.y *= %s.w;\n", fsName); |
| 41 builder->fFSCode.append("\tfloat d = length(offset);\n"); |
| 42 // compare length against xRadius |
| 43 builder->fFSCode.appendf("\tedgeAlpha = smoothstep(d - 0.5, d + 0.5, %s.
z);\n", fsName); |
| 44 builder->fFSCode.appendf("\t%s = ", outputColor); |
| 45 GrGLSLModulate4f(&builder->fFSCode, inputColor, "edgeAlpha"); |
| 46 builder->fFSCode.append(";\n"); |
| 47 |
| 48 } |
| 49 |
| 50 static inline EffectKey GenKey(const GrEffectStage& stage, const GrGLCaps&)
{ |
| 51 return 0; |
| 52 } |
| 53 |
| 54 virtual void setData(const GrGLUniformManager& uman, const GrEffectStage& st
age) SK_OVERRIDE { |
| 55 } |
| 56 |
| 57 private: |
| 58 typedef GrGLEffect INHERITED; |
| 59 }; |
| 60 |
| 61 /////////////////////////////////////////////////////////////////////////////// |
| 62 |
| 63 GrEllipseEdgeEffect::GrEllipseEdgeEffect() : GrEffect() { |
| 64 this->addVertexAttribName(ELLIPSE_EDGE_ATTR0); |
| 65 } |
| 66 |
| 67 void GrEllipseEdgeEffect::getConstantColorComponents(GrColor* color, uint32_t* v
alidFlags) const { |
| 68 *validFlags = 0; |
| 69 } |
| 70 |
| 71 const GrBackendEffectFactory& GrEllipseEdgeEffect::getFactory() const { |
| 72 return GrTBackendEffectFactory<GrEllipseEdgeEffect>::getInstance(); |
| 73 } |
| 74 |
| 75 /////////////////////////////////////////////////////////////////////////////// |
| 76 |
| 77 GR_DEFINE_EFFECT_TEST(GrEllipseEdgeEffect); |
| 78 |
| 79 GrEffectRef* GrEllipseEdgeEffect::TestCreate(SkMWCRandom* random, |
| 80 GrContext* context, |
| 81 GrTexture* textures[]) { |
| 82 return GrEllipseEdgeEffect::Create(); |
| 83 } |
OLD | NEW |