Re: Projective image transformations

On Sat, 2002-09-14 at 00:04, Keith Packard wrote:

    > The full mipmap stack costs only 1/3 as much memory as the base texture.  If
    > you're doing a lot of minification, it's usually considered a good tradeoff.
    
    As our source operands are writable objects, it seems like it will be 
    somewhat difficult to provide good semantics for mipmaps, but perhaps we 
    could build synthetic source pictures from sources at multiple resolutions 
    to do the same thing.  However, I think this remains just a performance 
    optimization at some level; I'm guessing most mipmaps are generated by 
    shrinking the larger image with a more accurate filter.

The other problem with mip-mapping is that while many modern hardware
implementations support non-power of 2 texture sizes, they generally
don't support mip-mapping non-power of 2 textures.  Since applications
using images generally don't use power of 2 image sizes, this GL
extension can save a lot of texture memory; it would be a tricky
tradeoff between that and improved texture filtering quality.


    J