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bubbaJr
05-04-2005, 10:32 AM
I'm still fairly new to OpenGL, so pardon me if I misuse/abuse some OGL terminology.

I read in the OpenGL SuperBible that creating display lists containing characters as textured quads was very much preferred to creating display lists containing bitmapped text. The performance of rendering characters as textured quads is 'spozed to be better than rendering bitmapped text.

Is this true? Am I misunderstanding the problem?

05-04-2005, 12:36 PM
Yes, ye're ri'ht...

When you output bitmapped text you directly write to image buffer, which is slow. You can temporaly disable all unneeded operations - such stenlic buffer test, but it will always slower than textured quads. If you are using quads, just set glLoadIdentity, then glOrtho an' you can easly specify text position...

Good luck

bansheeogl
05-04-2005, 12:36 PM
I believe its true although i havent got time to test it. display lists will help you improve performance when its about a lot of calls to the same thing.

and texturing quads is a good idea, and eats a couple of triangles only. also, I believe it works on any system and gfx card regarding its age no?

bubbaJr
05-04-2005, 01:39 PM
NeHe's Lesson 43 has an example of using bitmapped text converted to textured quads. But they use wgl UseBitMappedFontText(?not sure of the name), which the SuperBible says to avoid like the plague.