OpenSpace/modules/globebrowsing/shaders/interpolate_fs.glsl

/*****************************************************************************************
 *                                                                                       *
 * OpenSpace                                                                             *
 *                                                                                       *
 * Copyright (c) 2014-2025                                                               *
 *                                                                                       *
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 * software and associated documentation files (the "Software"), to deal in the Software *
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 * permit persons to whom the Software is furnished to do so, subject to the following   *
 * conditions:                                                                           *
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 * or substantial portions of the Software.                                              *
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 * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A         *
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 ****************************************************************************************/

#include "fragment.glsl"

in vec2 texCoord;

uniform sampler2D prevTexture;
uniform sampler2D nextTexture;
uniform sampler1D colormapTexture;
uniform float blendFactor;


Fragment getFragment() {
  vec4 texel0 = texture(prevTexture, texCoord);
  vec4 texel1 = texture(nextTexture, texCoord);

  vec4 mixedTexture = mix(texel0, texel1, blendFactor);

  Fragment frag;
  if (mixedTexture.r > 0.999) {
    frag.color = texture(colormapTexture, mixedTexture.r - 0.01);
  }
  else {
    frag.color = texture(colormapTexture, mixedTexture.r);
  }

  frag.color.a = mixedTexture.a;
  return frag;
}