Line data    Source code

       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 "GrGLSLVertexShaderBuilder.h"
       9             : #include "glsl/GrGLSLProgramBuilder.h"
      10             : #include "glsl/GrGLSLUniformHandler.h"
      11             : #include "glsl/GrGLSLVarying.h"
      12             : 
      13           0 : GrGLSLVertexBuilder::GrGLSLVertexBuilder(GrGLSLProgramBuilder* program)
      14           0 :     : INHERITED(program) {
      15           0 : }
      16             : 
      17           0 : void GrGLSLVertexBuilder::transformToNormalizedDeviceSpace(const GrShaderVar& posVar,
      18             :                                                            const char* rtAdjustName) {
      19             :     // setup RT Uniform
      20           0 :     if (this->getProgramBuilder()->desc()->header().fSnapVerticesToPixelCenters) {
      21           0 :         if (kVec3f_GrSLType == posVar.getType()) {
      22           0 :             const char* p = posVar.c_str();
      23           0 :             this->codeAppendf("{vec2 _posTmp = vec2(%s.x/%s.z, %s.y/%s.z);", p, p, p, p);
      24             :         } else {
      25           0 :             SkASSERT(kVec2f_GrSLType == posVar.getType());
      26           0 :             this->codeAppendf("{vec2 _posTmp = %s;", posVar.c_str());
      27             :         }
      28           0 :         this->codeAppendf("_posTmp = floor(_posTmp) + vec2(0.5, 0.5);"
      29             :                           "gl_Position = vec4(_posTmp.x * %s.x + %s.y,"
      30             :                                              "_posTmp.y * %s.z + %s.w, 0, 1);}",
      31           0 :                           rtAdjustName, rtAdjustName, rtAdjustName, rtAdjustName);
      32           0 :     } else if (kVec3f_GrSLType == posVar.getType()) {
      33           0 :         this->codeAppendf("gl_Position = vec4(dot(%s.xz, %s.xy), dot(%s.yz, %s.zw), 0, %s.z);",
      34             :                           posVar.c_str(), rtAdjustName,
      35             :                           posVar.c_str(), rtAdjustName,
      36           0 :                           posVar.c_str());
      37             :     } else {
      38           0 :         SkASSERT(kVec2f_GrSLType == posVar.getType());
      39           0 :         this->codeAppendf("gl_Position = vec4(%s.x * %s.x + %s.y, %s.y * %s.z + %s.w, 0, 1);",
      40             :                           posVar.c_str(), rtAdjustName, rtAdjustName,
      41           0 :                           posVar.c_str(), rtAdjustName, rtAdjustName);
      42             :     }
      43             :     // We could have the GrGeometryProcessor do this, but its just easier to have it performed
      44             :     // here. If we ever need to set variable pointsize, then we can reinvestigate.
      45           0 :     if (this->getProgramBuilder()->desc()->header().fHasPointSize) {
      46           0 :         this->codeAppend("gl_PointSize = 1.0;");
      47             :     }
      48           0 : }
      49             : 
      50           0 : void GrGLSLVertexBuilder::onFinalize() {
      51           0 :     fProgramBuilder->varyingHandler()->getVertexDecls(&this->inputs(), &this->outputs());
      52           0 : }