Path: chuka.playstation.co.uk!news From: Toby Sargeant Newsgroups: scee.yaroze.programming.3d_graphics Subject: Re: LOD Date: Tue, 22 Feb 2000 11:28:22 +1100 Organization: PlayStation Net Yaroze (SCEE) Lines: 33 Message-ID: <38B1D826.E69970B@fulcrum.com.au> References: <88eo73$cj112@chuka.playstation.co.uk> <88sj0g$ad1@chuka.playstation.co.uk> NNTP-Posting-Host: longford.csse.monash.edu.au Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Mailer: Mozilla 4.7 [en] (X11; I; Linux 2.2.14 i686) X-Accept-Language: en "Jon Prestidge (Moose)" wrote: > > What's LOD and FOV then? LOD - level of detail Doesn't mean all that much by itself. Generally people talk about progressive or adaptive level of detail which basically means modifying the complexity of objects in the scene as a result of a varying parameter. Commonly, this parameter is distance - objects in the foreground need to be more detailed, simply because they're bigger. Adaptive LOD could also be parameterised in terms of CPU/GPU load in order to keep a constant frame rate, or even in terms of percepual/focus values, making objects that the player should be concentrating on more detailed at the expense of less important stuff. FOV - field of view The angle formed by two opposite planes of the viewing frustrum. The viewing frustrum is simply the pyramidal space that is visible on the screen. The apex of the pyramid is the view/camera point, and the screen is a cross-sectional slice of the pyramid. When combined with near and far clipping planes, the result is a frustrum; a pyramid with the top lopped off. Widening the field of view affects various things, most notably the distortion that perspective creates. Toby.