Re: Experimental cairo port

[John Stowers <john stowers lists gmail com>]

> On the negative side though it is almost a magnitude of order slower. This is
> especially noticeable if many datapoints are drawn like in the rulers example.
> A simple solution I've tried is to filter the points and skip points which
> wouldn't be visible anyway, because they are identical to their predecessor.
> Part of the problem though is that cairo requires a function for each point
> which should be drawn. This results in a huge overhead, so another solution
> would be to use a cairo image surface and implement our own drawing functions
> and do raw pixel access.

This is really great.

Perhaps it is worth asking on the cairo mailing list for performance
advice - do you have a trace/oprofile run showing where time is spend
drawing?

John