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three.js/src/core/Ray.js
T

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JavaScript

/**
* @author mr.doob / http://mrdoob.com/
*/
THREE.Ray = function ( origin, direction ) {
this.origin = origin || new THREE.Vector3();
this.direction = direction || new THREE.Vector3();
}
THREE.Ray.prototype = {
intersectScene : function ( scene ) {
var i, l, object,
objects = scene.objects,
intersects = [];
for ( i = 0, l = objects.length; i < l; i++ ) {
object = objects[i];
if ( object instanceof THREE.Mesh ) {
intersects = intersects.concat( this.intersectObject( object ) );
}
}
intersects.sort( function ( a, b ) { return a.distance - b.distance; } );
return intersects;
},
intersectObject : function ( object ) {
var f, fl, face, a, b, c, d, normal,
dot, scalar,
origin, direction,
geometry = object.geometry,
vertices = geometry.vertices,
objMatrix,
intersect, intersects = [],
intersectPoint;
for ( f = 0, fl = geometry.faces.length; f < fl; f ++ ) {
face = geometry.faces[ f ];
origin = this.origin.clone();
direction = this.direction.clone();
objMatrix = object.matrixWorld;
a = objMatrix.multiplyVector3( vertices[ face.a ].position.clone() );
b = objMatrix.multiplyVector3( vertices[ face.b ].position.clone() );
c = objMatrix.multiplyVector3( vertices[ face.c ].position.clone() );
d = face instanceof THREE.Face4 ? objMatrix.multiplyVector3( vertices[ face.d ].position.clone() ) : null;
normal = object.matrixRotationWorld.multiplyVector3( face.normal.clone() );
dot = direction.dot( normal );
if ( object.doubleSided || ( object.flipSided ? dot > 0 : dot < 0 ) ) { // Math.abs( dot ) > 0.0001
scalar = normal.dot( new THREE.Vector3().sub( a, origin ) ) / dot;
intersectPoint = origin.addSelf( direction.multiplyScalar( scalar ) );
if ( face instanceof THREE.Face3 ) {
if ( pointInFace3( intersectPoint, a, b, c ) ) {
intersect = {
distance: this.origin.distanceTo( intersectPoint ),
point: intersectPoint,
face: face,
object: object
};
intersects.push( intersect );
}
} else if ( face instanceof THREE.Face4 ) {
if ( pointInFace3( intersectPoint, a, b, d ) || pointInFace3( intersectPoint, b, c, d ) ) {
intersect = {
distance: this.origin.distanceTo( intersectPoint ),
point: intersectPoint,
face: face,
object: object
};
intersects.push( intersect );
}
}
}
}
return intersects;
// http://www.blackpawn.com/texts/pointinpoly/default.html
function pointInFace3( p, a, b, c ) {
var v0 = c.clone().subSelf( a ), v1 = b.clone().subSelf( a ), v2 = p.clone().subSelf( a ),
dot00 = v0.dot( v0 ), dot01 = v0.dot( v1 ), dot02 = v0.dot( v2 ), dot11 = v1.dot( v1 ), dot12 = v1.dot( v2 ),
invDenom = 1 / ( dot00 * dot11 - dot01 * dot01 ),
u = ( dot11 * dot02 - dot01 * dot12 ) * invDenom,
v = ( dot00 * dot12 - dot01 * dot02 ) * invDenom;
return ( u > 0 ) && ( v > 0 ) && ( u + v < 1 );
}
}
};