fireball/lib/math/Frustum.js

import { Vector3 } from './Vector3.js';
import { Sphere } from './Sphere.js';
import { Plane } from './Plane.js';

/**
 * @author mrdoob / http://mrdoob.com/
 * @author alteredq / http://alteredqualia.com/
 * @author bhouston / http://clara.io
 */

function Frustum( p0, p1, p2, p3, p4, p5 ) {

	this.planes = [

		( p0 !== undefined ) ? p0 : new Plane(),
		( p1 !== undefined ) ? p1 : new Plane(),
		( p2 !== undefined ) ? p2 : new Plane(),
		( p3 !== undefined ) ? p3 : new Plane(),
		( p4 !== undefined ) ? p4 : new Plane(),
		( p5 !== undefined ) ? p5 : new Plane()

	];

}

Object.assign( Frustum.prototype, {

	set: function ( p0, p1, p2, p3, p4, p5 ) {

		var planes = this.planes;

		planes[ 0 ].copy( p0 );
		planes[ 1 ].copy( p1 );
		planes[ 2 ].copy( p2 );
		planes[ 3 ].copy( p3 );
		planes[ 4 ].copy( p4 );
		planes[ 5 ].copy( p5 );

		return this;

	},

	clone: function () {

		return new this.constructor().copy( this );

	},

	copy: function ( frustum ) {

		var planes = this.planes;

		for ( var i = 0; i < 6; i ++ ) {

			planes[ i ].copy( frustum.planes[ i ] );

		}

		return this;

	},

	setFromMatrix: function ( m ) {

		var planes = this.planes;
		var me = m.elements;
		var me0 = me[ 0 ], me1 = me[ 1 ], me2 = me[ 2 ], me3 = me[ 3 ];
		var me4 = me[ 4 ], me5 = me[ 5 ], me6 = me[ 6 ], me7 = me[ 7 ];
		var me8 = me[ 8 ], me9 = me[ 9 ], me10 = me[ 10 ], me11 = me[ 11 ];
		var me12 = me[ 12 ], me13 = me[ 13 ], me14 = me[ 14 ], me15 = me[ 15 ];

		planes[ 0 ].setComponents( me3 - me0, me7 - me4, me11 - me8, me15 - me12 ).normalize();
		planes[ 1 ].setComponents( me3 + me0, me7 + me4, me11 + me8, me15 + me12 ).normalize();
		planes[ 2 ].setComponents( me3 + me1, me7 + me5, me11 + me9, me15 + me13 ).normalize();
		planes[ 3 ].setComponents( me3 - me1, me7 - me5, me11 - me9, me15 - me13 ).normalize();
		planes[ 4 ].setComponents( me3 - me2, me7 - me6, me11 - me10, me15 - me14 ).normalize();
		planes[ 5 ].setComponents( me3 + me2, me7 + me6, me11 + me10, me15 + me14 ).normalize();

		return this;

	},

	intersectsObject: function () {

		var sphere = new Sphere();

		return function intersectsObject( object ) {

			var geometry = object.geometry;

			if ( geometry.boundingSphere === null )
				geometry.computeBoundingSphere();

			sphere.copy( geometry.boundingSphere )
				.applyMatrix4( object.matrixWorld );

			return this.intersectsSphere( sphere );

		};

	}(),

	intersectsSprite: function () {

		var sphere = new Sphere();

		return function intersectsSprite( sprite ) {

			sphere.center.set( 0, 0, 0 );
			sphere.radius = 0.7071067811865476;
			sphere.applyMatrix4( sprite.matrixWorld );

			return this.intersectsSphere( sphere );

		};

	}(),

	intersectsSphere: function ( sphere ) {

		var planes = this.planes;
		var center = sphere.center;
		var negRadius = - sphere.radius;

		for ( var i = 0; i < 6; i ++ ) {

			var distance = planes[ i ].distanceToPoint( center );

			if ( distance < negRadius ) {

				return false;

			}

		}

		return true;

	},

	intersectsBox: function () {

		var p = new Vector3();

		return function intersectsBox( box ) {

			var planes = this.planes;

			for ( var i = 0; i < 6; i ++ ) {

				var plane = planes[ i ];

				// corner at max distance

				p.x = plane.normal.x > 0 ? box.max.x : box.min.x;
				p.y = plane.normal.y > 0 ? box.max.y : box.min.y;
				p.z = plane.normal.z > 0 ? box.max.z : box.min.z;

				if ( plane.distanceToPoint( p ) < 0 ) {

					return false;

				}

			}

			return true;

		};

	}(),

	containsPoint: function ( point ) {

		var planes = this.planes;

		for ( var i = 0; i < 6; i ++ ) {

			if ( planes[ i ].distanceToPoint( point ) < 0 ) {

				return false;

			}

		}

		return true;

	}

} );


export { Frustum };