[link:http://en.wikipedia.org/wiki/Frustum Frustums] are used to determine what is
inside the camera's field of view. They help speed up the rendering process - objects which lie
outside a camera's frustum can safely be excluded from rendering.
This class is mainly intended for use internally by a renderer for calculating
a [page:Camera camera] or [page:LightShadow.camera shadowCamera]'s frustum.
[page:Plane p0] - (optional) defaults to a new [page:Plane].
[page:Plane p1] - (optional) defaults to a new [page:Plane].
[page:Plane p2] - (optional) defaults to a new [page:Plane].
[page:Plane p3] - (optional) defaults to a new [page:Plane].
[page:Plane p4] - (optional) defaults to a new [page:Plane].
[page:Plane p5] - (optional) defaults to a new [page:Plane].
Creates a new [name].
Array of 6 [page:Plane planes].
Return a new Frustum with the same parameters as this one.
[page:Vector3 point] - [page:Vector3] to test.
Checks to see if the frustum contains the [page:Vector3 point].
[page:Frustum frustum] - The frustum to copy
Copies the properties of the passed [page:Frustum frustum] into this one.
[page:Box3 box] - [page:Box3] to check for intersection.
Return true if [page:Box3 box] intersects with this frustum.
Checks whether the [page:Object3D object]'s [page:BufferGeometry.boundingSphere bounding sphere] is intersecting the Frustum.
Note that the object must have a [page:BufferGeometry geometry] so that the bounding sphere can be calculated.
[page:Sphere sphere] - [page:Sphere] to check for intersection.
Return true if [page:Sphere sphere] intersects with this frustum.
Checks whether the [page:Sprite sprite] is intersecting the Frustum.
Sets the frustum from the passed planes. No plane order is implied.
Note that this method only copies the values from the given objects.
[page:Matrix4 matrix] - Projection [page:Matrix4] used to set the [page:.planes planes]
Sets the frustum planes from the projection matrix.
[link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]