/**
|
* Converts an HSB color (hue, saturation, brightness) to RGB
|
* HSB <-> RGB conversion with minimal branching: {@link http://lolengine.net/blog/2013/07/27/rgb-to-hsv-in-glsl}
|
*
|
* @name czm_HSBToRGB
|
* @glslFunction
|
*
|
* @param {vec3} hsb The color in HSB.
|
*
|
* @returns {vec3} The color in RGB.
|
*
|
* @example
|
* vec3 hsb = czm_RGBToHSB(rgb);
|
* hsb.z *= 0.1;
|
* rgb = czm_HSBToRGB(hsb);
|
*/
|
|
const vec4 K_HSB2RGB = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0);
|
|
vec3 czm_HSBToRGB(vec3 hsb)
|
{
|
vec3 p = abs(fract(hsb.xxx + K_HSB2RGB.xyz) * 6.0 - K_HSB2RGB.www);
|
return hsb.z * mix(K_HSB2RGB.xxx, clamp(p - K_HSB2RGB.xxx, 0.0, 1.0), hsb.y);
|
}
|
