1 /* 2 * Copyright 2014 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 "GrGLGeometryShaderBuilder.h" 9 #include "GrGLShaderStringBuilder.h" 10 #include "GrGLProgramBuilder.h" 11 #include "../GrGpuGL.h" 12 13 GrGLGeometryShaderBuilder::GrGLGeometryShaderBuilder(GrGLFullProgramBuilder* program) 14 : INHERITED(program) { 15 16 } 17 18 void GrGLGeometryShaderBuilder::addVarying(GrSLType type, 19 const char* name, 20 const char** gsOutName) { 21 // if we have a GS take each varying in as an array 22 // and output as non-array. 23 fInputs.push_back(); 24 fInputs.back().setType(type); 25 fInputs.back().setTypeModifier(GrGLShaderVar::kVaryingIn_TypeModifier); 26 fInputs.back().setUnsizedArray(); 27 *fInputs.back().accessName() = name; 28 fOutputs.push_back(); 29 fOutputs.back().setType(type); 30 fOutputs.back().setTypeModifier(GrGLShaderVar::kVaryingOut_TypeModifier); 31 fProgramBuilder->nameVariable(fOutputs.back().accessName(), 'g', name); 32 if (gsOutName) { 33 *gsOutName = fOutputs.back().getName().c_str(); 34 } 35 } 36 37 38 bool GrGLGeometryShaderBuilder::compileAndAttachShaders(GrGLuint programId, 39 SkTDArray<GrGLuint>* shaderIds) const { 40 const GrGLContext& glCtx = fProgramBuilder->gpu()->glContext(); 41 SkASSERT(fProgramBuilder->ctxInfo().glslGeneration() >= k150_GrGLSLGeneration); 42 SkString geomShaderSrc(GrGetGLSLVersionDecl(fProgramBuilder->ctxInfo())); 43 geomShaderSrc.append("layout(triangles) in;\n" 44 "layout(triangle_strip, max_vertices = 6) out;\n"); 45 fProgramBuilder->appendDecls(fInputs, &geomShaderSrc); 46 fProgramBuilder->appendDecls(fOutputs, &geomShaderSrc); 47 geomShaderSrc.append("void main() {\n"); 48 geomShaderSrc.append("\tfor (int i = 0; i < 3; ++i) {\n" 49 "\t\tgl_Position = gl_in[i].gl_Position;\n"); 50 if (fProgramBuilder->desc().getHeader().fEmitsPointSize) { 51 geomShaderSrc.append("\t\tgl_PointSize = 1.0;\n"); 52 } 53 SkASSERT(fInputs.count() == fOutputs.count()); 54 for (int i = 0; i < fInputs.count(); ++i) { 55 geomShaderSrc.appendf("\t\t%s = %s[i];\n", 56 fOutputs[i].getName().c_str(), 57 fInputs[i].getName().c_str()); 58 } 59 geomShaderSrc.append("\t\tEmitVertex();\n" 60 "\t}\n" 61 "\tEndPrimitive();\n"); 62 geomShaderSrc.append("}\n"); 63 GrGLuint geomShaderId = 64 GrGLCompileAndAttachShader(glCtx, programId, 65 GR_GL_GEOMETRY_SHADER, geomShaderSrc, 66 fProgramBuilder->gpu()->gpuStats()); 67 if (!geomShaderId) { 68 return false; 69 } 70 *shaderIds->append() = geomShaderId; 71 return true; 72 } 73
