@pmndrs/pointer-events/dist/utils.js

framework agnostic pointer-events implementation for threejs

import { BufferAttribute, Matrix4, Triangle, Vector2, Vector3 } from 'three';
export function updateAndCheckWorldTransformation(object) {
    if (object.transformReady === false) {
        return false;
    }
    if (object.parent == null) {
        object.matrixWorld.copy(object.matrix);
        return true;
    }
    if (!updateAndCheckWorldTransformation(object.parent)) {
        return false;
    }
    //we can just use parent.matrixWorld here because we already executed `updateAndCheckWorldTransformation` before which has updated parent.matrixWorld
    object.matrixWorld.multiplyMatrices(object.parent.matrixWorld, object.matrix);
    return true;
}
const triangleHelper1 = new Triangle();
const triangleHelper2 = new Triangle();
const aVec2Helper = new Vector2();
const bVec2Helper = new Vector2();
const cVec2Helper = new Vector2();
const pointHelper = new Vector3();
const inverseMatrix = new Matrix4();
const localPointHelper = new Vector3();
/**
 * @requires that `mesh.updateWorldMatrix(true, false)` was executed beforehand
 */
export function getClosestUV(target, point, mesh) {
    localPointHelper.copy(point).applyMatrix4(inverseMatrix.copy(mesh.matrixWorld).invert());
    const uv = mesh.geometry.attributes.uv;
    if (uv == null || !(uv instanceof BufferAttribute)) {
        return false;
    }
    let clostestDistance;
    loopThroughTriangles(mesh, (i1, i2, i3) => {
        mesh.getVertexPosition(i1, triangleHelper1.a);
        mesh.getVertexPosition(i2, triangleHelper1.b);
        mesh.getVertexPosition(i3, triangleHelper1.c);
        const distance = triangleHelper1.closestPointToPoint(localPointHelper, pointHelper).distanceTo(localPointHelper);
        if (clostestDistance != null && distance >= clostestDistance) {
            return;
        }
        clostestDistance = distance;
        triangleHelper2.copy(triangleHelper1);
        aVec2Helper.fromBufferAttribute(uv, i1);
        bVec2Helper.fromBufferAttribute(uv, i2);
        cVec2Helper.fromBufferAttribute(uv, i3);
    });
    if (clostestDistance == null) {
        return false;
    }
    triangleHelper2.closestPointToPoint(localPointHelper, pointHelper);
    triangleHelper2.getInterpolation(pointHelper, aVec2Helper, bVec2Helper, cVec2Helper, target);
    return true;
}
function loopThroughTriangles(mesh, fn) {
    const drawRange = mesh.geometry.drawRange;
    if (mesh.geometry.index != null) {
        const index = mesh.geometry.index;
        const start = Math.max(0, drawRange.start);
        const end = Math.min(index.count, drawRange.start + drawRange.count);
        for (let i = start; i < end; i += 3) {
            fn(index.getX(i), index.getX(i + 1), index.getX(i + 2));
        }
        return;
    }
    const position = mesh.geometry.attributes.position;
    if (position == null) {
        return;
    }
    const start = Math.max(0, drawRange.start);
    const end = Math.min(position.count, drawRange.start + drawRange.count);
    for (let i = start; i < end; i += 3) {
        fn(i, i + 1, i + 2);
    }
}