[cairo] [PATCH] Support image filtering in xlib and xcb backends

Bill Spitzak spitzak at gmail.com
Thu Aug 14 18:29:07 PDT 2014

On 08/14/2014 04:30 PM, Bryce Harrington wrote:
> On Tue, Aug 12, 2014 at 08:06:35PM -0700, Bill Spitzak wrote:

>> - I did not test the xcb changes.

Is there any easy way to get cairo to render into an xcb backend?

>> - I am assuming other backends treat bilinear and good identically,
>> at least for scales larger than 1/1.35.

A search seems to indicate that all other backends just look for whether 
it is FAST/NEAREST or not. So they do not care about bilinear verses good.

I suspect some backends, in particular the drm ones, are not doing the 
filtering, and need a similar fallback. I am not clear however. Lots of 
other backends I think are doing "good" filtering even if bilinear is 
selected, this is probably ok.

>> - A CAIRO_RENDER option maybe should be added in case pixman ever
>> supports GOOD/BEST.

It is probably best to add the config option or flag now. I think pixman 
will support this some day, though there certainly was resistance to my 
first attempt to send a patch for it.

> Should the above notes be taken care of before this is merged?

I will try to add the flags indicating if the filters work and send 
another patch.

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