michael@0: /*
michael@0:  * Copyright 2011 Google Inc.
michael@0:  *
michael@0:  * Use of this source code is governed by a BSD-style license that can be
michael@0:  * found in the LICENSE file.
michael@0:  */
michael@0: 
michael@0: #include "GrGLSL.h"
michael@0: #include "GrGLShaderVar.h"
michael@0: #include "SkString.h"
michael@0: 
michael@0: GrGLSLGeneration GrGetGLSLGeneration(const GrGLInterface* gl) {
michael@0:     GrGLSLVersion ver = GrGLGetGLSLVersion(gl);
michael@0:     switch (gl->fStandard) {
michael@0:         case kGL_GrGLStandard:
michael@0:             SkASSERT(ver >= GR_GLSL_VER(1,10));
michael@0:             if (ver >= GR_GLSL_VER(1,50)) {
michael@0:                 return k150_GrGLSLGeneration;
michael@0:             } else if (ver >= GR_GLSL_VER(1,40)) {
michael@0:                 return k140_GrGLSLGeneration;
michael@0:             } else if (ver >= GR_GLSL_VER(1,30)) {
michael@0:                 return k130_GrGLSLGeneration;
michael@0:             } else {
michael@0:                 return k110_GrGLSLGeneration;
michael@0:             }
michael@0:         case kGLES_GrGLStandard:
michael@0:             // version 1.00 of ES GLSL based on ver 1.20 of desktop GLSL
michael@0:             SkASSERT(ver >= GR_GL_VER(1,00));
michael@0:             return k110_GrGLSLGeneration;
michael@0:         default:
michael@0:             GrCrash("Unknown GL Standard");
michael@0:             return k110_GrGLSLGeneration; // suppress warning
michael@0:     }
michael@0: }
michael@0: 
michael@0: const char* GrGetGLSLVersionDecl(const GrGLContextInfo& info) {
michael@0:     switch (info.glslGeneration()) {
michael@0:         case k110_GrGLSLGeneration:
michael@0:             if (kGLES_GrGLStandard == info.standard()) {
michael@0:                 // ES2s shader language is based on version 1.20 but is version
michael@0:                 // 1.00 of the ES language.
michael@0:                 return "#version 100\n";
michael@0:             } else {
michael@0:                 SkASSERT(kGL_GrGLStandard == info.standard());
michael@0:                 return "#version 110\n";
michael@0:             }
michael@0:         case k130_GrGLSLGeneration:
michael@0:             SkASSERT(kGL_GrGLStandard == info.standard());
michael@0:             return "#version 130\n";
michael@0:         case k140_GrGLSLGeneration:
michael@0:             SkASSERT(kGL_GrGLStandard == info.standard());
michael@0:             return "#version 140\n";
michael@0:         case k150_GrGLSLGeneration:
michael@0:             SkASSERT(kGL_GrGLStandard == info.standard());
michael@0:             if (info.caps()->isCoreProfile()) {
michael@0:                 return "#version 150\n";
michael@0:             } else {
michael@0:                 return "#version 150 compatibility\n";
michael@0:             }
michael@0:         default:
michael@0:             GrCrash("Unknown GL version.");
michael@0:             return ""; // suppress warning
michael@0:     }
michael@0: }
michael@0: 
michael@0: namespace {
michael@0:     void append_tabs(SkString* outAppend, int tabCnt) {
michael@0:         static const char kTabs[] = "\t\t\t\t\t\t\t\t";
michael@0:         while (tabCnt) {
michael@0:             int cnt = GrMin((int)GR_ARRAY_COUNT(kTabs), tabCnt);
michael@0:             outAppend->append(kTabs, cnt);
michael@0:             tabCnt -= cnt;
michael@0:         }
michael@0:     }
michael@0: }
michael@0: 
michael@0: void GrGLSLMulVarBy4f(SkString* outAppend,
michael@0:                       unsigned tabCnt,
michael@0:                       const char* vec4VarName,
michael@0:                       const GrGLSLExpr4& mulFactor) {
michael@0:     if (mulFactor.isOnes()) {
michael@0:         *outAppend = SkString();
michael@0:     }
michael@0: 
michael@0:     append_tabs(outAppend, tabCnt);
michael@0: 
michael@0:     if (mulFactor.isZeros()) {
michael@0:         outAppend->appendf("%s = vec4(0);\n", vec4VarName);
michael@0:     } else {
michael@0:         outAppend->appendf("%s *= %s;\n", vec4VarName, mulFactor.c_str());
michael@0:     }
michael@0: }