[cairo] Re: [Mesa3d-dev] Points in Cairo Glitz paper

[Ian Romanick]

Vladimir Vukicevic wrote:
> David Reveman wrote:
>> On Sun, 2004-04-25 at 11:01 -0600, Marcelo E. Magallon wrote:
>>
>>> I didn't take a closer look at the convolution operation and I'm not
>>> sure if the imaging extensions are capable of providing equal
>>> functionality.
>>
>> I've actually tried using the imaging extensions for convolution
>> filtering but it turned out terribly slow. 
> 
> Some time ago, a friend was doing some work with the imaging extensions. 
>  It turned out that neither nVidia nor ATI make any real attempts to 
> optimize/accelerate them -- the majority of operations are terribly slow 
> under both linux and win32.  It's probably not worth depending on 
> ARB_imaging for much of anything, though I'm not sure if representing 
> operations using ARB_imaging would help Mesa accelerate those operations 
> (hand tailored assembly, etc.).

On most "consumer" hardware the majority of operations in ARB_imaging 
are software fallbacks.  There are a number of things that, with some 
effort, could be partially accelerated with hardware, however.  Most 
people working on drivers (open-source or closed-source) haven't done 
this because it's a fair amount of effort and the market hasn't demanded it.

The market drives everything.

If there were important applications that needed fast imaging to be 
fast, and Nvidia or ATI thought bumping performance in those application 
would sell more chips, you had better believe imaging performance would 
improve. :)