[cairo] Performance of the image surface back-end

[Vladimir Vukicevic]

On Aug 15, 2008, at 6:20 AM, Nicholas Allen wrote:
> Cairo (image surface back-end version 1.6.4 on Windows):
>
> ~     DrawHorizLine                 44352 ms             1000000 solid
> horiz lines from 0.5, 50.5 to 500.5, 50.5

This is not actually a pixel-aligned horizontal line, unless you are  
using the non-default SQUARE endcaps.  The horizontal line would be  
from 0.0, 50.5 to 501.0, 50.5.  With this line, you are getting  
essentially the slowest possible path for path rasterization; however,  
even with that, it seems quite slow.  As others mentioned, seeing the  
source for your benchmark would be useful!  (If, however, you are  
explicitly setting SQUARE endcaps, then something is likely going  
quite wrong.)

     - Vlad