playcanvas

Version:
Open-source WebGL/WebGPU 3D engine for the web
25 lines (24 loc) • 1.07 kB
JavaScript
var lightSpecularGGX_default = `
fn calcLightSpecular(gloss: f32, worldNormal: vec3f, viewDir: vec3f, h: vec3f, lightDirNorm: vec3f) -> f32 {
	const PI: f32 = 3.141592653589793;
	let roughness: f32 = max((1.0 - gloss) * (1.0 - gloss), 0.001);
	let alpha: f32 = roughness * roughness;
	let NoH: f32 = max(dot(worldNormal, h), 0.0);
	let NoV: f32 = max(dot(worldNormal, viewDir), 0.0);
	let NoL: f32 = max(dot(worldNormal, -lightDirNorm), 0.0);
	let NoH2: f32 = NoH * NoH;
	let denom: f32 = NoH2 * (alpha - 1.0) + 1.0;
	let D: f32 = alpha / (PI * denom * denom);
	let alpha2: f32 = alpha * alpha;
	let lambdaV: f32 = NoL * sqrt(NoV * NoV * (1.0 - alpha2) + alpha2);
	let lambdaL: f32 = NoV * sqrt(NoL * NoL * (1.0 - alpha2) + alpha2);
	let G: f32 = 0.5 / max(lambdaV + lambdaL, 0.00001);
	return D * G;
}
fn getLightSpecular(h: vec3f, reflDir: vec3f, worldNormal: vec3f, viewDir: vec3f, lightDirNorm: vec3f, gloss: f32, tbn: mat3x3f) -> f32 {
	return calcLightSpecular(gloss, worldNormal, viewDir, h, lightDirNorm);
}
`;
export {
	lightSpecularGGX_default as default
};