Mipmapping for canvas. Ideas and comments.

[Boudewijn Rempt]

On Thu, 23 Jul 2009, Lukast dev wrote:

> >> Well, it seems that KisImage level really fits better.
> >> Btw, doesn't OpenGL has it's own _hardware_ downsampling? Or even
> >> mipmapping? I guess it's quite unreasonably to emulate mipmapping with cpu
> >> when gpu can do it faster?
> >
> > Lukas is looking into that.
> >
> 
> OpenGL uses some small textures (tiles) that are mapped on planes
> (quads) and when
> the image is scaled, you can decide what algorithm is used. See [1]
> There are also mip-map versions. I used bi-linear interpolation for
> zoom til 2.0 (200 %), and nearest neighbohour at higher zoom.

I think the pyramid doesn't make much sense for the opengl canvas indeed,
which is an argument to implement it in KisProjectionCache.

Boudewijn