Re: [AD] power-of-two textures?

[Milan Mimica <milan.mimica@xxxxxxxxxx>]

Evert Glebbeek wrote:
> AllegroGL has (used to have?) a way to cope with non-power-of-two  
> textures, but I've forgotten the details. I assume we could use the  
> same method?

No, we'd better not use the same method. :)

This is how it works:
If EXT_NPOT is not available, try EXT_TEXTURE_RECTANGLE. If neither is 
available, split the texture into smaller POT textures. For example, a 
3000x500 bitmap is then split into (2^11,2^9,2^8,2^7,2^5,2^4,2^3 x 
2^8,2^7,2^6,2^5,2^4,2^2) 42 pieces! Doing anything to such a bitmap is 
slow as hell. And it's hard to test.

Using a subitmap might be a better solution. Maybe not even try 
EXT_TEXTURE_RECTANGLE because it requires special coordinate handing 
when blitting it. It would use less video memory though.

Splitting a too large bitmap should not produce too many fragments, so 
that should be fine, just because there isn't a better solution apparently.


--
Milan Mimica
http://sparklet.sf.net