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wood
03-10-2003, 02:13 AM
what is open GL card.

jin choung
03-10-2003, 03:36 AM
open gl is an API - APPLICATION PROGRAMMING INTERFACE....

that is, programmers have to talk to the graphics card to tell it how to draw polygons and whatnot.

normally, that requires very LOW LEVEL CALLS to the hardware. meaning, programming at or near assembly language level.

that is a PAIN IN THE BUTT.

programmers like to work in "higher level languages" like c or c++ because it's more like english and you can do a lot more with less lines of code.

opengl gives you commands in c++ that will TRANSLATE to the lower level calls to the graphics card (or its drivers) so that programmers can continue to program as they wish in higher level languages but still control the graphics card.

that's why it's called an INTERFACE.
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Open GL is not the only 3d api. another very popular one in windows is DIRECT 3D. but that's limited to systems running windows. and also, it was designed almost specifically for gaming.

opengl was originally developed by SGI and goes waaaaaaaay back. so it's been used from early military flight sims to CAD apps etc. it is also cross platform so opengl can be used as a programming interface in macs, linux, unix, etc.

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just like 3d used to be a very rareified application for computers - limited only to scientists and military, it used to be that you needed a VERY EXPENSIVE high powered graphics card, usually commonly called an OPENGL CARD.

these were meant for hard core, professionals and the price of the cards reflected it. they also sported a great deal more ram than any consumer cards. their drivers were also highly tuned to get optimal performance for professional applications like 3d apps and cad, etc.

BUT

nowadays, many consumer graphics cards sport a great deal of onboard ram (128mb) and are probably as fast as you'll ever need. the drivers, especially from companies like nvidia are rock solid so that you get tremendous performance in apps like maya and lw, as well as in games like quake3.

they still make "opengl cards" and they still do boast better performance in the pro apps but PRICEPERFORMANCE wise, it just doesn't make that much sense to buy a pro board over a consumer one.

jin

Global Hawk
03-10-2003, 01:20 PM
Yea. What he said!;)

Miles
03-10-2003, 01:51 PM
Great response jin choung! :D

Epita
03-12-2003, 03:12 PM
Open Glide, just incase and Direct 3Dimentionall (picky)

Geforce 4 (supafast)

Epita

mattclary
03-12-2003, 03:17 PM
That would be Open Graphics Language.

jin choung
03-12-2003, 03:34 PM
right,

it's open graphics language.

GLIDE is an early consumer 3d API made from 3dfx.

alas, they've gone belly up and have been acquired by nvidia. and glide is no longer used in modern applications.

though there still are a great many excellent older games that either require glide or enforce software rendering (no graphics card acceleration).

jin