playcanvas/build/playcanvas/src/scene/shader-lib/wgsl/chunks/gsplat/vert/gsplatSogsData.js

PlayCanvas WebGL game engine

var gsplatSogsDataVS = `
var means_u: texture_2d<f32>;
var means_l: texture_2d<f32>;
var quats: texture_2d<f32>;
var scales: texture_2d<f32>;
uniform means_mins: vec3f;
uniform means_maxs: vec3f;
uniform scales_mins: vec3f;
uniform scales_maxs: vec3f;
fn readCenter(source: ptr<function, SplatSource>) -> vec3f {
	let u: vec3f = textureLoad(means_u, source.uv, 0).xyz;
	let l: vec3f = textureLoad(means_l, source.uv, 0).xyz;
	let n: vec3f = (l * 255.0 + u * 255.0 * 256.0) / 65535.0;
	let v: vec3f = mix(uniform.means_mins, uniform.means_maxs, n);
	return sign(v) * (exp(abs(v)) - 1.0);
}
const norm: f32 = 2.0 / sqrt(2.0);
fn readCovariance(source: ptr<function, SplatSource>, covA_ptr: ptr<function, vec3f>, covB_ptr: ptr<function, vec3f>) {
	let qdata: vec4f = textureLoad(quats, source.uv, 0);
	let abc: vec3f = (qdata.xyz - 0.5) * norm;
	let d: f32 = sqrt(max(0.0, 1.0 - dot(abc, abc)));
	let mode: u32 = u32(qdata.w * 255.0 + 0.5) - 252u;
	var quat: vec4f;
	if (mode == 0u) {
		quat = vec4f(d, abc);
	} else if (mode == 1u) {
		quat = vec4f(abc.x, d, abc.y, abc.z);
	} else if (mode == 2u) {
		quat = vec4f(abc.x, abc.y, d, abc.z);
	} else {
		quat = vec4f(abc.x, abc.y, abc.z, d);
	}
	let rot: mat3x3f = quatToMat3(quat);
	let scale: vec3f = exp(mix(uniform.scales_mins, uniform.scales_maxs, textureLoad(scales, source.uv, 0).xyz));
	let M: mat3x3f = transpose(mat3x3f(
		scale.x * rot[0],
		scale.y * rot[1],
		scale.z * rot[2]
	));
	*covA_ptr = vec3f(dot(M[0], M[0]), dot(M[0], M[1]), dot(M[0], M[2]));
	*covB_ptr = vec3f(dot(M[1], M[1]), dot(M[1], M[2]), dot(M[2], M[2]));
}
`;

export { gsplatSogsDataVS as default };