three
Version:
JavaScript 3D library
295 lines (215 loc) • 7.76 kB
JavaScript
import {
Frustum,
Vector3,
Matrix4,
Quaternion,
} from 'three';
const _frustum = new Frustum();
const _center = new Vector3();
const _tmpPoint = new Vector3();
const _vecNear = new Vector3();
const _vecTopLeft = new Vector3();
const _vecTopRight = new Vector3();
const _vecDownRight = new Vector3();
const _vecDownLeft = new Vector3();
const _vecFarTopLeft = new Vector3();
const _vecFarTopRight = new Vector3();
const _vecFarDownRight = new Vector3();
const _vecFarDownLeft = new Vector3();
const _vectemp1 = new Vector3();
const _vectemp2 = new Vector3();
const _vectemp3 = new Vector3();
const _matrix = new Matrix4();
const _quaternion = new Quaternion();
const _scale = new Vector3();
/**
* This class can be used to select 3D objects in a scene with a selection box.
* It is recommended to visualize the selected area with the help of {@link SelectionHelper}.
*
* ```js
* const selectionBox = new SelectionBox( camera, scene );
* const selectedObjects = selectionBox.select( startPoint, endPoint );
* ```
*
* @three_import import { SelectionBox } from 'three/addons/interactive/SelectionBox.js';
*/
class SelectionBox {
/**
* Constructs a new selection box.
*
* @param {Camera} camera - The camera the scene is rendered with.
* @param {Scene} scene - The scene.
* @param {number} [deep=Number.MAX_VALUE] - How deep the selection frustum of perspective cameras should extend.
*/
constructor( camera, scene, deep = Number.MAX_VALUE ) {
/**
* The camera the scene is rendered with.
*
* @type {Camera}
*/
this.camera = camera;
/**
* The camera the scene is rendered with.
*
* @type {Scene}
*/
this.scene = scene;
/**
* The start point of the selection.
*
* @type {Vector3}
*/
this.startPoint = new Vector3();
/**
* The end point of the selection.
*
* @type {Vector3}
*/
this.endPoint = new Vector3();
/**
* The selected 3D objects.
*
* @type {Array<Object3D>}
*/
this.collection = [];
/**
* The selected instance IDs of instanced meshes.
*
* @type {Object}
*/
this.instances = {};
/**
* How deep the selection frustum of perspective cameras should extend.
*
* @type {number}
* @default Number.MAX_VALUE
*/
this.deep = deep;
}
/**
* This method selects 3D objects in the scene based on the given start
* and end point. If no parameters are provided, the method uses the start
* and end values of the respective members.
*
* @param {Vector3} [startPoint] - The start point.
* @param {Vector3} [endPoint] - The end point.
* @return {Array<Object3D>} The selected 3D objects.
*/
select( startPoint, endPoint ) {
this.startPoint = startPoint || this.startPoint;
this.endPoint = endPoint || this.endPoint;
this.collection = [];
this._updateFrustum( this.startPoint, this.endPoint );
this._searchChildInFrustum( _frustum, this.scene );
return this.collection;
}
// private
_updateFrustum( startPoint, endPoint ) {
startPoint = startPoint || this.startPoint;
endPoint = endPoint || this.endPoint;
// Avoid invalid frustum
if ( startPoint.x === endPoint.x ) {
endPoint.x += Number.EPSILON;
}
if ( startPoint.y === endPoint.y ) {
endPoint.y += Number.EPSILON;
}
this.camera.updateProjectionMatrix();
this.camera.updateMatrixWorld();
if ( this.camera.isPerspectiveCamera ) {
_tmpPoint.copy( startPoint );
_tmpPoint.x = Math.min( startPoint.x, endPoint.x );
_tmpPoint.y = Math.max( startPoint.y, endPoint.y );
endPoint.x = Math.max( startPoint.x, endPoint.x );
endPoint.y = Math.min( startPoint.y, endPoint.y );
_vecNear.setFromMatrixPosition( this.camera.matrixWorld );
_vecTopLeft.copy( _tmpPoint );
_vecTopRight.set( endPoint.x, _tmpPoint.y, 0 );
_vecDownRight.copy( endPoint );
_vecDownLeft.set( _tmpPoint.x, endPoint.y, 0 );
_vecTopLeft.unproject( this.camera );
_vecTopRight.unproject( this.camera );
_vecDownRight.unproject( this.camera );
_vecDownLeft.unproject( this.camera );
_vectemp1.copy( _vecTopLeft ).sub( _vecNear );
_vectemp2.copy( _vecTopRight ).sub( _vecNear );
_vectemp3.copy( _vecDownRight ).sub( _vecNear );
_vectemp1.normalize();
_vectemp2.normalize();
_vectemp3.normalize();
_vectemp1.multiplyScalar( this.deep );
_vectemp2.multiplyScalar( this.deep );
_vectemp3.multiplyScalar( this.deep );
_vectemp1.add( _vecNear );
_vectemp2.add( _vecNear );
_vectemp3.add( _vecNear );
const planes = _frustum.planes;
planes[ 0 ].setFromCoplanarPoints( _vecNear, _vecTopLeft, _vecTopRight );
planes[ 1 ].setFromCoplanarPoints( _vecNear, _vecTopRight, _vecDownRight );
planes[ 2 ].setFromCoplanarPoints( _vecDownRight, _vecDownLeft, _vecNear );
planes[ 3 ].setFromCoplanarPoints( _vecDownLeft, _vecTopLeft, _vecNear );
planes[ 4 ].setFromCoplanarPoints( _vecTopRight, _vecDownRight, _vecDownLeft );
planes[ 5 ].setFromCoplanarPoints( _vectemp3, _vectemp2, _vectemp1 );
planes[ 5 ].normal.multiplyScalar( - 1 );
} else if ( this.camera.isOrthographicCamera ) {
const left = Math.min( startPoint.x, endPoint.x );
const top = Math.max( startPoint.y, endPoint.y );
const right = Math.max( startPoint.x, endPoint.x );
const down = Math.min( startPoint.y, endPoint.y );
_vecTopLeft.set( left, top, - 1 );
_vecTopRight.set( right, top, - 1 );
_vecDownRight.set( right, down, - 1 );
_vecDownLeft.set( left, down, - 1 );
_vecFarTopLeft.set( left, top, 1 );
_vecFarTopRight.set( right, top, 1 );
_vecFarDownRight.set( right, down, 1 );
_vecFarDownLeft.set( left, down, 1 );
_vecTopLeft.unproject( this.camera );
_vecTopRight.unproject( this.camera );
_vecDownRight.unproject( this.camera );
_vecDownLeft.unproject( this.camera );
_vecFarTopLeft.unproject( this.camera );
_vecFarTopRight.unproject( this.camera );
_vecFarDownRight.unproject( this.camera );
_vecFarDownLeft.unproject( this.camera );
const planes = _frustum.planes;
planes[ 0 ].setFromCoplanarPoints( _vecTopLeft, _vecFarTopLeft, _vecFarTopRight );
planes[ 1 ].setFromCoplanarPoints( _vecTopRight, _vecFarTopRight, _vecFarDownRight );
planes[ 2 ].setFromCoplanarPoints( _vecFarDownRight, _vecFarDownLeft, _vecDownLeft );
planes[ 3 ].setFromCoplanarPoints( _vecFarDownLeft, _vecFarTopLeft, _vecTopLeft );
planes[ 4 ].setFromCoplanarPoints( _vecTopRight, _vecDownRight, _vecDownLeft );
planes[ 5 ].setFromCoplanarPoints( _vecFarDownRight, _vecFarTopRight, _vecFarTopLeft );
planes[ 5 ].normal.multiplyScalar( - 1 );
} else {
console.error( 'THREE.SelectionBox: Unsupported camera type.' );
}
}
_searchChildInFrustum( frustum, object ) {
if ( object.isMesh || object.isLine || object.isPoints ) {
if ( object.isInstancedMesh ) {
this.instances[ object.uuid ] = [];
for ( let instanceId = 0; instanceId < object.count; instanceId ++ ) {
object.getMatrixAt( instanceId, _matrix );
_matrix.decompose( _center, _quaternion, _scale );
_center.applyMatrix4( object.matrixWorld );
if ( frustum.containsPoint( _center ) ) {
this.instances[ object.uuid ].push( instanceId );
}
}
} else {
if ( object.geometry.boundingSphere === null ) object.geometry.computeBoundingSphere();
_center.copy( object.geometry.boundingSphere.center );
_center.applyMatrix4( object.matrixWorld );
if ( frustum.containsPoint( _center ) ) {
this.collection.push( object );
}
}
}
if ( object.children.length > 0 ) {
for ( let x = 0; x < object.children.length; x ++ ) {
this._searchChildInFrustum( frustum, object.children[ x ] );
}
}
}
}
export { SelectionBox };