three
Version:
JavaScript 3D library
262 lines (201 loc) • 8.16 kB
JavaScript
import { Matrix4 } from '../math/Matrix4.js';
import { Ray } from '../math/Ray.js';
import { Layers } from './Layers.js';
const _matrix = /*@__PURE__*/ new Matrix4();
/**
* This class is designed to assist with raycasting. Raycasting is used for
* mouse picking (working out what objects in the 3d space the mouse is over)
* amongst other things.
*/
class Raycaster {
/**
* Constructs a new raycaster.
*
* @param {Vector3} origin - The origin vector where the ray casts from.
* @param {Vector3} direction - The (normalized) direction vector that gives direction to the ray.
* @param {number} [near=0] - All results returned are further away than near. Near can't be negative.
* @param {number} [far=Infinity] - All results returned are closer than far. Far can't be lower than near.
*/
constructor( origin, direction, near = 0, far = Infinity ) {
/**
* The ray used for raycasting.
*
* @type {Ray}
*/
this.ray = new Ray( origin, direction );
/**
* All results returned are further away than near. Near can't be negative.
*
* @type {number}
* @default 0
*/
this.near = near;
/**
* All results returned are further away than near. Near can't be negative.
*
* @type {number}
* @default Infinity
*/
this.far = far;
/**
* The camera to use when raycasting against view-dependent objects such as
* billboarded objects like sprites. This field can be set manually or
* is set when calling `setFromCamera()`.
*
* @type {?Camera}
* @default null
*/
this.camera = null;
/**
* Allows to selectively ignore 3D objects when performing intersection tests.
* The following code example ensures that only 3D objects on layer `1` will be
* honored by raycaster.
* ```js
* raycaster.layers.set( 1 );
* object.layers.enable( 1 );
* ```
*
* @type {Layers}
*/
this.layers = new Layers();
/**
* A parameter object that configures the raycasting. It has the structure:
*
* ```
* {
* Mesh: {},
* Line: { threshold: 1 },
* LOD: {},
* Points: { threshold: 1 },
* Sprite: {}
* }
* ```
* Where `threshold` is the precision of the raycaster when intersecting objects, in world units.
*
* @type {Object}
*/
this.params = {
Mesh: {},
Line: { threshold: 1 },
LOD: {},
Points: { threshold: 1 },
Sprite: {}
};
}
/**
* Updates the ray with a new origin and direction by copying the values from the arguments.
*
* @param {Vector3} origin - The origin vector where the ray casts from.
* @param {Vector3} direction - The (normalized) direction vector that gives direction to the ray.
*/
set( origin, direction ) {
// direction is assumed to be normalized (for accurate distance calculations)
this.ray.set( origin, direction );
}
/**
* Uses the given coordinates and camera to compute a new origin and direction for the internal ray.
*
* @param {Vector2} coords - 2D coordinates of the mouse, in normalized device coordinates (NDC).
* X and Y components should be between `-1` and `1`.
* @param {Camera} camera - The camera from which the ray should originate.
*/
setFromCamera( coords, camera ) {
if ( camera.isPerspectiveCamera ) {
this.ray.origin.setFromMatrixPosition( camera.matrixWorld );
this.ray.direction.set( coords.x, coords.y, 0.5 ).unproject( camera ).sub( this.ray.origin ).normalize();
this.camera = camera;
} else if ( camera.isOrthographicCamera ) {
this.ray.origin.set( coords.x, coords.y, ( camera.near + camera.far ) / ( camera.near - camera.far ) ).unproject( camera ); // set origin in plane of camera
this.ray.direction.set( 0, 0, - 1 ).transformDirection( camera.matrixWorld );
this.camera = camera;
} else {
console.error( 'THREE.Raycaster: Unsupported camera type: ' + camera.type );
}
}
/**
* Uses the given WebXR controller to compute a new origin and direction for the internal ray.
*
* @param {WebXRController} controller - The controller to copy the position and direction from.
* @return {Raycaster} A reference to this raycaster.
*/
setFromXRController( controller ) {
_matrix.identity().extractRotation( controller.matrixWorld );
this.ray.origin.setFromMatrixPosition( controller.matrixWorld );
this.ray.direction.set( 0, 0, - 1 ).applyMatrix4( _matrix );
return this;
}
/**
* The intersection point of a raycaster intersection test.
* @typedef {Object} Raycaster~Intersection
* @property {number} distance - The distance from the ray's origin to the intersection point.
* @property {number} distanceToRay - Some 3D objects e.g. {@link Points} provide the distance of the
* intersection to the nearest point on the ray. For other objects it will be `undefined`.
* @property {Vector3} point - The intersection point, in world coordinates.
* @property {Object} face - The face that has been intersected.
* @property {number} faceIndex - The face index.
* @property {Object3D} object - The 3D object that has been intersected.
* @property {Vector2} uv - U,V coordinates at point of intersection.
* @property {Vector2} uv1 - Second set of U,V coordinates at point of intersection.
* @property {Vector3} uv1 - Interpolated normal vector at point of intersection.
* @property {number} instanceId - The index number of the instance where the ray
* intersects the {@link InstancedMesh}.
*/
/**
* Checks all intersection between the ray and the object with or without the
* descendants. Intersections are returned sorted by distance, closest first.
*
* `Raycaster` delegates to the `raycast()` method of the passed 3D object, when
* evaluating whether the ray intersects the object or not. This allows meshes to respond
* differently to ray casting than lines or points.
*
* Note that for meshes, faces must be pointed towards the origin of the ray in order
* to be detected; intersections of the ray passing through the back of a face will not
* be detected. To raycast against both faces of an object, you'll want to set {@link Material#side}
* to `THREE.DoubleSide`.
*
* @param {Object3D} object - The 3D object to check for intersection with the ray.
* @param {boolean} [recursive=true] - If set to `true`, it also checks all descendants.
* Otherwise it only checks intersection with the object.
* @param {Array<Raycaster~Intersection>} [intersects=[]] The target array that holds the result of the method.
* @return {Array<Raycaster~Intersection>} An array holding the intersection points.
*/
intersectObject( object, recursive = true, intersects = [] ) {
intersect( object, this, intersects, recursive );
intersects.sort( ascSort );
return intersects;
}
/**
* Checks all intersection between the ray and the objects with or without
* the descendants. Intersections are returned sorted by distance, closest first.
*
* @param {Array<Object3D>} objects - The 3D objects to check for intersection with the ray.
* @param {boolean} [recursive=true] - If set to `true`, it also checks all descendants.
* Otherwise it only checks intersection with the object.
* @param {Array<Raycaster~Intersection>} [intersects=[]] The target array that holds the result of the method.
* @return {Array<Raycaster~Intersection>} An array holding the intersection points.
*/
intersectObjects( objects, recursive = true, intersects = [] ) {
for ( let i = 0, l = objects.length; i < l; i ++ ) {
intersect( objects[ i ], this, intersects, recursive );
}
intersects.sort( ascSort );
return intersects;
}
}
function ascSort( a, b ) {
return a.distance - b.distance;
}
function intersect( object, raycaster, intersects, recursive ) {
let propagate = true;
if ( object.layers.test( raycaster.layers ) ) {
const result = object.raycast( raycaster, intersects );
if ( result === false ) propagate = false;
}
if ( propagate === true && recursive === true ) {
const children = object.children;
for ( let i = 0, l = children.length; i < l; i ++ ) {
intersect( children[ i ], raycaster, intersects, true );
}
}
}
export { Raycaster };