three
Version:
JavaScript 3D library
150 lines (111 loc) • 3.77 kB
JavaScript
import { Box3 } from '../math/Box3.js';
import { LineSegments } from '../objects/LineSegments.js';
import { LineBasicMaterial } from '../materials/LineBasicMaterial.js';
import { BufferAttribute } from '../core/BufferAttribute.js';
import { BufferGeometry } from '../core/BufferGeometry.js';
const _box = /*@__PURE__*/ new Box3();
/**
* Helper object to graphically show the world-axis-aligned bounding box
* around an object. The actual bounding box is handled with {@link Box3},
* this is just a visual helper for debugging. It can be automatically
* resized with {@link BoxHelper#update} when the object it's created from
* is transformed. Note that the object must have a geometry for this to work,
* so it won't work with sprites.
*
* ```js
* const sphere = new THREE.SphereGeometry();
* const object = new THREE.Mesh( sphere, new THREE.MeshBasicMaterial( 0xff0000 ) );
* const box = new THREE.BoxHelper( object, 0xffff00 );
* scene.add( box );
* ```
*
* @augments LineSegments
*/
class BoxHelper extends LineSegments {
/**
* Constructs a new box helper.
*
* @param {Object3D} [object] - The 3D object to show the world-axis-aligned bounding box.
* @param {number|Color|string} [color=0xffff00] - The box's color.
*/
constructor( object, color = 0xffff00 ) {
const indices = new Uint16Array( [ 0, 1, 1, 2, 2, 3, 3, 0, 4, 5, 5, 6, 6, 7, 7, 4, 0, 4, 1, 5, 2, 6, 3, 7 ] );
const positions = new Float32Array( 8 * 3 );
const geometry = new BufferGeometry();
geometry.setIndex( new BufferAttribute( indices, 1 ) );
geometry.setAttribute( 'position', new BufferAttribute( positions, 3 ) );
super( geometry, new LineBasicMaterial( { color: color, toneMapped: false } ) );
/**
* The 3D object being visualized.
*
* @type {Object3D}
*/
this.object = object;
this.type = 'BoxHelper';
this.matrixAutoUpdate = false;
this.update();
}
/**
* Updates the helper's geometry to match the dimensions of the object,
* including any children.
*/
update() {
if ( this.object !== undefined ) {
_box.setFromObject( this.object );
}
if ( _box.isEmpty() ) return;
const min = _box.min;
const max = _box.max;
/*
5____4
1/___0/|
| 6__|_7
2/___3/
0: max.x, max.y, max.z
1: min.x, max.y, max.z
2: min.x, min.y, max.z
3: max.x, min.y, max.z
4: max.x, max.y, min.z
5: min.x, max.y, min.z
6: min.x, min.y, min.z
7: max.x, min.y, min.z
*/
const position = this.geometry.attributes.position;
const array = position.array;
array[ 0 ] = max.x; array[ 1 ] = max.y; array[ 2 ] = max.z;
array[ 3 ] = min.x; array[ 4 ] = max.y; array[ 5 ] = max.z;
array[ 6 ] = min.x; array[ 7 ] = min.y; array[ 8 ] = max.z;
array[ 9 ] = max.x; array[ 10 ] = min.y; array[ 11 ] = max.z;
array[ 12 ] = max.x; array[ 13 ] = max.y; array[ 14 ] = min.z;
array[ 15 ] = min.x; array[ 16 ] = max.y; array[ 17 ] = min.z;
array[ 18 ] = min.x; array[ 19 ] = min.y; array[ 20 ] = min.z;
array[ 21 ] = max.x; array[ 22 ] = min.y; array[ 23 ] = min.z;
position.needsUpdate = true;
this.geometry.computeBoundingSphere();
}
/**
* Updates the wireframe box for the passed object.
*
* @param {Object3D} object - The 3D object to create the helper for.
* @return {BoxHelper} A reference to this instance.
*/
setFromObject( object ) {
this.object = object;
this.update();
return this;
}
copy( source, recursive ) {
super.copy( source, recursive );
this.object = source.object;
return this;
}
/**
* Frees the GPU-related resources allocated by this instance. Call this
* method whenever this instance is no longer used in your app.
*/
dispose() {
this.geometry.dispose();
this.material.dispose();
}
}
export { BoxHelper };