@cesium/engine
Version:
CesiumJS is a JavaScript library for creating 3D globes and 2D maps in a web browser without a plugin.
33 lines (32 loc) • 984 B
JavaScript
//This file is automatically rebuilt by the Cesium build process.
export default "/**\n\
* Converts an RGB color to CIE Yxy.\n\
* <p>The conversion is described in\n\
* {@link http://content.gpwiki.org/index.php/D3DBook:High-Dynamic_Range_Rendering#Luminance_Transform|Luminance Transform}\n\
* </p>\n\
* \n\
* @name czm_RGBToXYZ\n\
* @glslFunction\n\
* \n\
* @param {vec3} rgb The color in RGB.\n\
*\n\
* @returns {vec3} The color in CIE Yxy.\n\
*\n\
* @example\n\
* vec3 xyz = czm_RGBToXYZ(rgb);\n\
* xyz.x = max(xyz.x - luminanceThreshold, 0.0);\n\
* rgb = czm_XYZToRGB(xyz);\n\
*/\n\
vec3 czm_RGBToXYZ(vec3 rgb)\n\
{\n\
const mat3 RGB2XYZ = mat3(0.4124, 0.2126, 0.0193,\n\
0.3576, 0.7152, 0.1192,\n\
0.1805, 0.0722, 0.9505);\n\
vec3 xyz = RGB2XYZ * rgb;\n\
vec3 Yxy;\n\
Yxy.r = xyz.g;\n\
float temp = dot(vec3(1.0), xyz);\n\
Yxy.gb = xyz.rg / temp;\n\
return Yxy;\n\
}\n\
";