//This file is automatically rebuilt by the Cesium build process.
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export default "/**\n\
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* Adjusts the hue of a color.\n\
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* \n\
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* @name czm_hue\n\
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* @glslFunction\n\
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* \n\
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* @param {vec3} rgb The color.\n\
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* @param {float} adjustment The amount to adjust the hue of the color in radians.\n\
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*\n\
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* @returns {float} The color with the hue adjusted.\n\
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*\n\
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* @example\n\
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* vec3 adjustHue = czm_hue(color, czm_pi); // The same as czm_hue(color, -czm_pi)\n\
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*/\n\
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vec3 czm_hue(vec3 rgb, float adjustment)\n\
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{\n\
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const mat3 toYIQ = mat3(0.299, 0.587, 0.114,\n\
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0.595716, -0.274453, -0.321263,\n\
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0.211456, -0.522591, 0.311135);\n\
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const mat3 toRGB = mat3(1.0, 0.9563, 0.6210,\n\
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1.0, -0.2721, -0.6474,\n\
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1.0, -1.107, 1.7046);\n\
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\n\
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vec3 yiq = toYIQ * rgb;\n\
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float hue = atan(yiq.z, yiq.y) + adjustment;\n\
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float chroma = sqrt(yiq.z * yiq.z + yiq.y * yiq.y);\n\
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\n\
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vec3 color = vec3(yiq.x, chroma * cos(hue), chroma * sin(hue));\n\
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return toRGB * color;\n\
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}\n\
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";
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