three
Version:
JavaScript 3D library
228 lines (122 loc) • 4.35 kB
JavaScript
import { Matrix3 } from './Matrix3.js';
import { Vector3 } from './Vector3.js';
const _vector1 = new Vector3();
const _vector2 = new Vector3();
const _normalMatrix = new Matrix3();
function Plane( normal, constant ) {
// normal is assumed to be normalized
this.normal = ( normal !== undefined ) ? normal : new Vector3( 1, 0, 0 );
this.constant = ( constant !== undefined ) ? constant : 0;
}
Object.assign( Plane.prototype, {
isPlane: true,
set: function ( normal, constant ) {
this.normal.copy( normal );
this.constant = constant;
return this;
},
setComponents: function ( x, y, z, w ) {
this.normal.set( x, y, z );
this.constant = w;
return this;
},
setFromNormalAndCoplanarPoint: function ( normal, point ) {
this.normal.copy( normal );
this.constant = - point.dot( this.normal );
return this;
},
setFromCoplanarPoints: function ( a, b, c ) {
const normal = _vector1.subVectors( c, b ).cross( _vector2.subVectors( a, b ) ).normalize();
// Q: should an error be thrown if normal is zero (e.g. degenerate plane)?
this.setFromNormalAndCoplanarPoint( normal, a );
return this;
},
clone: function () {
return new this.constructor().copy( this );
},
copy: function ( plane ) {
this.normal.copy( plane.normal );
this.constant = plane.constant;
return this;
},
normalize: function () {
// Note: will lead to a divide by zero if the plane is invalid.
const inverseNormalLength = 1.0 / this.normal.length();
this.normal.multiplyScalar( inverseNormalLength );
this.constant *= inverseNormalLength;
return this;
},
negate: function () {
this.constant *= - 1;
this.normal.negate();
return this;
},
distanceToPoint: function ( point ) {
return this.normal.dot( point ) + this.constant;
},
distanceToSphere: function ( sphere ) {
return this.distanceToPoint( sphere.center ) - sphere.radius;
},
projectPoint: function ( point, target ) {
if ( target === undefined ) {
console.warn( 'THREE.Plane: .projectPoint() target is now required' );
target = new Vector3();
}
return target.copy( this.normal ).multiplyScalar( - this.distanceToPoint( point ) ).add( point );
},
intersectLine: function ( line, target ) {
if ( target === undefined ) {
console.warn( 'THREE.Plane: .intersectLine() target is now required' );
target = new Vector3();
}
const direction = line.delta( _vector1 );
const denominator = this.normal.dot( direction );
if ( denominator === 0 ) {
// line is coplanar, return origin
if ( this.distanceToPoint( line.start ) === 0 ) {
return target.copy( line.start );
}
// Unsure if this is the correct method to handle this case.
return undefined;
}
const t = - ( line.start.dot( this.normal ) + this.constant ) / denominator;
if ( t < 0 || t > 1 ) {
return undefined;
}
return target.copy( direction ).multiplyScalar( t ).add( line.start );
},
intersectsLine: function ( line ) {
// Note: this tests if a line intersects the plane, not whether it (or its end-points) are coplanar with it.
const startSign = this.distanceToPoint( line.start );
const endSign = this.distanceToPoint( line.end );
return ( startSign < 0 && endSign > 0 ) || ( endSign < 0 && startSign > 0 );
},
intersectsBox: function ( box ) {
return box.intersectsPlane( this );
},
intersectsSphere: function ( sphere ) {
return sphere.intersectsPlane( this );
},
coplanarPoint: function ( target ) {
if ( target === undefined ) {
console.warn( 'THREE.Plane: .coplanarPoint() target is now required' );
target = new Vector3();
}
return target.copy( this.normal ).multiplyScalar( - this.constant );
},
applyMatrix4: function ( matrix, optionalNormalMatrix ) {
const normalMatrix = optionalNormalMatrix || _normalMatrix.getNormalMatrix( matrix );
const referencePoint = this.coplanarPoint( _vector1 ).applyMatrix4( matrix );
const normal = this.normal.applyMatrix3( normalMatrix ).normalize();
this.constant = - referencePoint.dot( normal );
return this;
},
translate: function ( offset ) {
this.constant -= offset.dot( this.normal );
return this;
},
equals: function ( plane ) {
return plane.normal.equals( this.normal ) && ( plane.constant === this.constant );
}
} );
export { Plane };