Re: porting Xlib/Motif apps to GTK+

[Just Fill Bugs <mozbugbox yahoo com au>]

On 03/01/2012 04:07 AM, Roger Davis wrote:
> Hi Dov,
>
> Thanks very much for that interesting code example. I built it and it
> seems to work fine, so there is apparently a solution to my problem,
> however complicated it may turn out to be. I assume since no one has
> given me a short 'yes' answer to my question of whether you can easily
> do an XOR line draw in Cairo that the answer is in fact 'no'. That's
> really too bad, XOR is such a nice, easy solution to quickly drawing a
> visible overlay line (when one is not particular about its actual color)
> and then rapidly restoring the original underlying drawing with an XOR
> erase. A few of my rubberbanding operations are unfortunately a lot more
> complicated than just a single line or box.
>
> I will definitely save this very useful demo code, and probably bug you
> about it sometime in the future when I get to the point of rewriting all
> of my Xlib drawing ops. (Lucky you! ;-> )



If it is in cairo operators, it can be done. Else, no.

http://cairographics.org/manual/cairo-cairo-t.html#cairo-operator-t