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2b7aae2 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 | import { BufferGeometry } from '../core/BufferGeometry.js';
import { Float32BufferAttribute } from '../core/BufferAttribute.js';
import { Vector3 } from '../math/Vector3.js';
class WireframeGeometry extends BufferGeometry {
constructor(geometry = null) {
super();
this.type = 'WireframeGeometry';
this.parameters = {
geometry: geometry,
};
if (geometry !== null) {
// buffer
const vertices = [];
const edges = new Set();
// helper variables
const start = new Vector3();
const end = new Vector3();
if (geometry.index !== null) {
// indexed BufferGeometry
const position = geometry.attributes.position;
const indices = geometry.index;
let groups = geometry.groups;
if (groups.length === 0) {
groups = [{ start: 0, count: indices.count, materialIndex: 0 }];
}
// create a data structure that contains all eges without duplicates
for (let o = 0, ol = groups.length; o < ol; ++o) {
const group = groups[o];
const groupStart = group.start;
const groupCount = group.count;
for (let i = groupStart, l = groupStart + groupCount; i < l; i += 3) {
for (let j = 0; j < 3; j++) {
const index1 = indices.getX(i + j);
const index2 = indices.getX(i + ((j + 1) % 3));
start.fromBufferAttribute(position, index1);
end.fromBufferAttribute(position, index2);
if (isUniqueEdge(start, end, edges) === true) {
vertices.push(start.x, start.y, start.z);
vertices.push(end.x, end.y, end.z);
}
}
}
}
} else {
// non-indexed BufferGeometry
const position = geometry.attributes.position;
for (let i = 0, l = position.count / 3; i < l; i++) {
for (let j = 0; j < 3; j++) {
// three edges per triangle, an edge is represented as (index1, index2)
// e.g. the first triangle has the following edges: (0,1),(1,2),(2,0)
const index1 = 3 * i + j;
const index2 = 3 * i + ((j + 1) % 3);
start.fromBufferAttribute(position, index1);
end.fromBufferAttribute(position, index2);
if (isUniqueEdge(start, end, edges) === true) {
vertices.push(start.x, start.y, start.z);
vertices.push(end.x, end.y, end.z);
}
}
}
}
// build geometry
this.setAttribute('position', new Float32BufferAttribute(vertices, 3));
}
}
}
function isUniqueEdge(start, end, edges) {
const hash1 = `${start.x},${start.y},${start.z}-${end.x},${end.y},${end.z}`;
const hash2 = `${end.x},${end.y},${end.z}-${start.x},${start.y},${start.z}`; // coincident edge
if (edges.has(hash1) === true || edges.has(hash2) === true) {
return false;
} else {
edges.add(hash1, hash2);
return true;
}
}
export { WireframeGeometry };
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