Ugh... Qt4 porting

[Mosfet]

Lars wrote:
> I said the math behind it is trivial. And yes, I do think that changing code
> to handle the premultiplied values instead of non premultiplied ones should
> in almost all cases be not too hard.  

Except it doesn't really work, as has been pointed out ;-) 

This is how I see things: You have an image format that is really fast with a 
paint device and XRender but that modifies the pixel values in a way that 
looses precision getting original RGB values back.

Okay fine. Support the format but minimize it's usage, document it's problems 
and tell developers that once converted to this format they won't be able to 
get the original RGB values back. 

There will be a very limited set of filters that will work on these images, 
but that doesn't mean you have to drop it entirely. Consider it more as an 
"accelerated format for viewing images" whereas the normal format is for 
editing them. 

And I still want my create() and jumpTable() methods back, and possibly a 
pointer to the colorTable QVector data so you don't have to use copies ;-)