From: "Hargreaves, Shawn" To: "'djgpp AT delorie DOT com'" Subject: Re: dirty stuff Date: Wed, 20 Aug 97 13:24:00 PDT Message-ID: <33FB53A4@relay.probe.co.uk> Encoding: 27 TEXT Precedence: bulk Alan Poppleton writes: > What do people mean when they talk about dirty stuff when discussing > graphics? For example 'dirty rectangles'. Dirty rectangles are a commonly used technique for reducing the amount of screen space that needs to be updated when displaying animations. In many situations, only a small part of the screen will change from one frame to the next, and well-written graphics routines will exploit this coherency by only bothering to redraw the areas that have changed, ie. the regions that are "dirty" and need to be updated with the new image... > Also what is this 'foo' variable that keeps cropping up everywhere? 'foo' is a commonly used name for almost anything (variables, functions, files, etc) where the name itself doesn't matter, for example as a placeholder to use in example code or documentation. When someone tells you to type "strcpy(foo, bar)", they don't mean literally to type in the string foo, but insert whatever name is relevant to your situation instead. See http://www.lysator.liu.se/hackdict/split2/metasyntactic_variable.html. Shawn Hargreaves.