Re: [linuxgames] Poll: Video Access

[Francesco Orsenigo <xarvh@lombardiacom.it>]

Adam D. Moss:
>  > How can estimate the texture memory usage?
>
>  System memory or graphics card memory?  It's hard to pin down
>  which (and how much of each) will be used, as it's largely
>  down to the driver and the capabilities of the card.

I should be able to estimate quite precisely how much system memory i'm i 
using.
My problems concern graphics card internal representation.

>  It depends.  You can ask OpenGL to use a specific internal
>  representation (there are many different OpenGL-internal
>  representations you can ask it to use, including RGBA packed
>  2/2/2/2 into the bits of one byte -- but you won't always get
>  what you ask for) if you know what space/quality tradeoff
>  you're aiming for for a particular texture.

Ok, i can call glTexImage2D() with a lot of parameters.
But i always assumed that the gfx card would translate it to his internal 
format, wich size i don't know.

(cut)
>  I don't remember what answers you got originally.  I'm sure that
>  someone would have suggested textured palettes (though they're
>  somewhat deprecated).
No.
Steve just suggested to split the sprite in 2 images: the one with unchanged 
colors, to be drawn first, and a second one with just the areas that must be 
colored.

>  If you want to get fancy and really want to encode all this
>  info in a single texture to work on all OpenGL implementations,
>  I think you could use a single alpha channel to encode both the
>  outline-mask and the tinting-levels by:
(cut)

Smart.
It seems the key is the glTexEnv*() function, wich i'm going to learn.
I'm trying it.

Thanx,
Francesco Orsenigo