gpu-curtains/dist/esm/core/shaders/chunks/fragment/body/get-specular.mjs

gpu-curtains is a 3D WebGPU rendering engine. It can be used as a standalone 3D engine, but also includes extra classes focused on mapping 3d objects to DOM elements; It allows users to synchronize values such as position, sizing, or scale between them.

import { getTextureSample } from "./get-texture-sample.mjs";
//#region src/core/shaders/chunks/fragment/body/get-specular.ts
/**
* Set the `specularIntensity` (`f32`) and `specularColor` (`vec3f`) values from the material specular variables and eventual specular textures.
* @param parameters - Parameters used to set the `specularIntensity` (`f32`) and `specularColor` (`vec3f`) values.
* @param parameters.specularTexture - {@link ShaderTextureDescriptor | Specular texture descriptor} (mixing both specular color in the `RGB` channels and specular intensity in the `A` channel) to use if any.
* @param parameters.specularFactorTexture - {@link ShaderTextureDescriptor | Specular intensity texture descriptor} (using the `A` channel) to use if any.
* @param parameters.specularColorTexture - {@link ShaderTextureDescriptor | Specular color texture descriptor} (using the `RGB` channels) to use if any.
* @returns - String with the `specularIntensity` (`f32`) and `specularColor` (`vec3f`) values set.
*/
const getSpecular = ({ specularTexture = null, specularFactorTexture = null, specularColorTexture = null } = {}) => {
	let specular = `
  var specularF90: f32 = 1.0;`;
	if (specularTexture) {
		specular += getTextureSample(specularTexture, "specular");
		specular += `
  specularIntensity = specularIntensity * specularSample.a;
  specularColor = specularColor * specularSample.rgb;`;
	} else {
		if (specularFactorTexture) {
			specular += getTextureSample(specularFactorTexture, "specularFactor");
			specular += `
  specularIntensity = specularIntensity * specularFactorSample.a;`;
		}
		if (specularColorTexture) {
			specular += getTextureSample(specularColorTexture, "specularColor");
			specular += `
  specularColor = specularColor * specularColorSample.rgb;`;
		}
	}
	specular += `
  specularF90 = mix(specularIntensity, 1.0, metallic);
  specularColor = min( pow2( ( ior - 1.0 ) / ( ior + 1.0 ) ) * specularColor, vec3( 1.0 ) ) * specularIntensity;
  let specularColorBlended: vec3f = mix(specularColor, diffuseColor, metallic);
  `;
	return specular;
};
//#endregion
export { getSpecular };