@openhps/core
Version:
Open Hybrid Positioning System - Core component
38 lines (35 loc) • 1.1 kB
JavaScript
import TempNode from '../core/TempNode.js';
import { transformedNormalView } from '../accessors/Normal.js';
import { positionViewDirection } from '../accessors/Position.js';
import { nodeImmutable, vec2, vec3 } from '../tsl/TSLBase.js';
/**
* Can be used to compute texture coordinates for projecting a
* matcap onto a mesh. Used by {@link MeshMatcapNodeMaterial}.
*
* @augments TempNode
*/
class MatcapUVNode extends TempNode {
static get type() {
return 'MatcapUVNode';
}
/**
* Constructs a new matcap uv node.
*/
constructor() {
super('vec2');
}
setup() {
const x = vec3(positionViewDirection.z, 0, positionViewDirection.x.negate()).normalize();
const y = positionViewDirection.cross(x);
return vec2(x.dot(transformedNormalView), y.dot(transformedNormalView)).mul(0.495).add(0.5); // 0.495 to remove artifacts caused by undersized matcap disks
}
}
export default MatcapUVNode;
/**
* TSL function for creating a matcap uv node.
*
* @tsl
* @function
* @returns {MatcapUVNode}
*/
export const matcapUV = /*@__PURE__*/nodeImmutable(MatcapUVNode);