@kitware/vtk.js/Rendering/OpenGL/SurfaceLIC/glsl/vtkSurfaceLICInterface_CE.glsl.js

Visualization Toolkit for the Web

var vtkSurfaceLICInterface_CE = "//VTK::System::Dec\n\n//=========================================================================\n//\n//  Program:   Visualization Toolkit\n//  Module:    vtkSurfaceLICMapper_CE.glsl\n//\n//  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen\n//  All rights reserved.\n//  See Copyright.txt or http://www.kitware.com/Copyright.htm for details.\n//\n//     This software is distributed WITHOUT ANY WARRANTY; without even\n//     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR\n//     PURPOSE.  See the above copyright notice for more information.\n//\n//=========================================================================\n\n// color contrast enhance stage implemented via histogram stretching\n// on lightness channel. if the min and max are tweaked it can generate\n// out-of-range values these will be clamped in 0 to 1\n\n// the output of this shader\n//VTK::Output::Dec\n\nuniform sampler2D texGeomColors; // scalars + lighting\nuniform sampler2D texLIC;        // image lic, mask\nuniform sampler2D texHSLColors;  // hsla colors\n\nuniform float     uLMin;         // min lightness over all fragments\nuniform float     uLMaxMinDiff;  // max - min lightness over all fragments\n\nin vec2 tcoordVC;\n\nvec3 HSLToRGB(vec3 HSL)\n{\n  vec3 RGB;\n  float v;\n  float h = HSL.x;\n  float sl = HSL.y;\n  float l = HSL.z;\n\n  v = (l <= 0.5) ? (l * (1.0 + sl)) : (l + sl - l * sl);\n  if (v <= 0.0) {\n    RGB = vec3(0.0,0.0,0.0);\n  } else {\n    float m;\n    int sextant;\n    float fract, vsf, mid1, mid2;\n\n    m = l + l - v;\n    h *= 6.0;\n    sextant = int(h);\n    fract = h - float(sextant);\n\n    vsf = (v - m) * fract;\n    mid1 = m + vsf;\n    mid2 = v - vsf;\n    switch (sextant) {\n      case 0: RGB.r = v; RGB.g = mid1; RGB.b = m; break;\n      case 1: RGB.r = mid2; RGB.g = v; RGB.b = m; break;\n      case 2: RGB.r = m; RGB.g = v; RGB.b = mid1; break;\n      case 3: RGB.r = m; RGB.g = mid2; RGB.b = v; break;\n      case 4: RGB.r = mid1; RGB.g = m; RGB.b = v; break;\n      case 5: RGB.r = v; RGB.g = m; RGB.b = mid2; break;\n    }\n  }\n  return RGB;\n}\n\nvoid main()\n{\n  // lookup hsl color , mask\n  vec4 fragColor = texture2D(texHSLColors, tcoordVC.st);\n\n  // don't modify masked fragments (masked => lic.g==1)\n  vec4 lic = texture2D(texLIC, tcoordVC.st);\n  if (lic.g==0.0)\n    {\n    // normalize lightness channel\n    fragColor.z = clamp((fragColor.z - uLMin)/uLMaxMinDiff, 0.0, 1.0);\n    }\n\n  // back into rgb space\n  fragColor.rgb = HSLToRGB(fragColor.xyz);\n\n  // add alpha\n  vec4 geomColor = texture2D(texGeomColors, tcoordVC.st);\n  fragColor.a = geomColor.a;\n\n  gl_FragData[0] = fragColor;\n}\n";

export { vtkSurfaceLICInterface_CE as v };