[cairo] drawing into GDK bitmap (pixmap of depth 1)?

[Eric Smith]

Owen wrote:
> IIRC, when you use a GTK+ bitmap with Cairo it's treated as a 1-bit
> alpha bitmap, so you might want to try adjusting you code appropriately.

OK.  That's an interesting interpretation, and I never would have guessed
that.

> Try - set_operator(CAIRO_CLEAR); cairo_fill(); rather than painting
> with black.

That solved the problem.

So with CAIRO_OPERATOR_SOURCE, anything I stroke or fill in a bitmap
is going to be "white" (non-clear)?

Thanks!
Eric