Function GetVectorLookupProgram

Rendering/LICOpenGL2/vtkLineIntegralConvolution2D.cxx:743–776

Shader code for looking up vectors */

Shader code for looking up vectors
*/
const char* GetVectorLookupProgram(int normalize)
{
  // lookup the vector and normalize
  const char* getNormVecSrc = " \
    vec2 getVector( vec2 vectc )\n \
      {\n \
      vec2 V = texture2D( texVectors, vectc ).xy;\n \
      // normalize if |V| not 0\n \
      float lenV = length( V );\n \
      if ( lenV > 1.0e-8 )\n \
        {\n \
        return V/lenV;\n \
        }\n \
      else\n \
        {\n \
        return vec2( 0.0, 0.0 );\n \
        }\n \
      }\n \
    ";

  // lookup the vector
  const char* getVecSrc = " \
    vec2 getVector( vec2 vectc )\n \
      {\n \
      return texture2D( texVectors, vectc ).xy;\n \
      }\n \
    ";

  if (normalize)
  {
    return getNormVecSrc;
  }
  return getVecSrc;
}

#ifdef STREAMING_MIN_MAX
// Description