[cairo] What happened to my patches to Pixman for image filtering?

Bill Spitzak spitzak at gmail.com
Wed Oct 29 12:03:02 PDT 2014

Quite some time ago I posted patches to Pixman to fix several bugs in 
the filter generator and to implement GOOD/BEST filtering. My first set 
got a response from Søren Sandmann, but I believe I addressed this 
response in my second series of patches (V5 in this mailing list, and 

  <1411783570-24329-1-git-send-email-spitzak at gmail.com>

Have not heard anything since then.

I believe it would be much better to patch Pixman than my current 
support of filters in Cairo. But it is possible the authors disagree.

Søren did state that he felt that having GOOD/BEST do anything other 
than bilinear may be a bad idea, and that callers should use the filter 
api. However I disagree, primarily because pixman can make numerous 
optimizations (such as using bilinear for some transformations) because 
it knows exactly what filter GOOD and BEST produce. Also it is trivial 
to use BILINEAR if that is what the caller really wants.

I also would like to support 2-pass and non-affine transforms but this 
is going to be considerable work on pixman, so I would like some 
assurances that patches will be considered so I am not wasting my time.

I am sending this only to the cairo list as my previous email all had 
both the cairo and pixman lists as recipients. I am worried this may 
have caused people's email filters to put it in the wrong bin and it was 
never seen.

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