Camera arguments in Three.js

Question

This is how a camera is instantiated:

var camera = new THREE.PerspectiveCamera(
    VIEW_ANGLE,
    ASPECT,
    NEAR,
    FAR
);

What do these values mean?

Answer 1

I was wondering the same thing so I looked it up, it is a view "frustum".

I'll paste here a code comment I wrote in a recent project because it sums it up nicely IMHO.

// "What the f*** is a frustum?" you ask. Well I did.
// Think about it as a truncated pyramid. The tip is the camera. From a certain
// point "down" the pyramid (the "near plane"), stuff can be seen on-screen.
// After the "base" of the pyramid (the "far plane"), stuff is too far to be
// seen. Stuff outside the pyramid is off-screen too. There is also the "aspect
// ratio" (the rectangle that makes up the pyramid's base, so this value is
// width/height) and the "field of view" (think of it as a lens or something,
// it distorts the pyramid so there's more objects on screen - it is set in
// degrees and 45° is more-or-less a "natural" perspective. The bigger the
// number, the more "perspective" there is).

                                         

Answer 2

The first param is FOV means field of view, imagine a camera on a tripod, if you change lens to wide angle you get a higher FOV. Try to imagine a cone coming out from the camera, it can only see objects in that area.

ASPECT means aspect ratio, a widescreen TV is 16/9 and old ones were 4/3, usually just give it the screen width/height or the dims of a DIV you would like three.js to use.