mrdoob/three.js — Issue #941: Quick one: Clarity on perspective camera's field of view.
Author: interactiveluke
Created: 2011-12-20 16:24:17+00:00
State: open

Hi, I'm trying to work out the maths of sizing a sphere to fill a dynamically sized canvas width, although to do so, the FOV variable is confusing me.

I understand that the camera works by showing everything inside of the 'viewing frustum', although how is there only one FOV angle? Surely if the canvas or aspect ratio weren't square, there would be two field of view angles, one for each of vertical and horizontal? Though there is only one defined, so my main question is, where would FOV fit into this diagram? http://techpubs.sgi.com/library/dynaweb_docs/0650/SGI_Developer/books/Perf_PG/sgi_html/figures/04.3.frustum.gif

Thanks! Luke.