[ardour-dev] gtkpixscrollbar

[torbenh at informatik.uni-bremen.de]

On Wed, Mar 10, 2004 at 12:10:14AM +0000, Steve Harris wrote:
> On Tue, Mar 09, 2004 at 06:31:54 -0500, Paul Davis wrote:
> > when you create a pixmap from XPM data (or an XPM file) you get two
> > data structures, the pixmap and a bitmap (1 bit pixmap). the bitmap is
> > the "mask". so, to create a custom scrollbar, get the XPM data (or
> 
> I've a feeling that GDK 2 pixmpas can include alpha data, I might well be
> wrong about that though.

you are correct. see src/gtkknob.c in galan.
i use it already for the knob. the slider is not updated yet.

and suggest that this is the way to go.
have a png with alpha layer and render that onto your widgets window.

gdk 2 can now directly render a pixbuf onto a drawable like it can
render a line. these calls have to be used for alpha.



-- 
torben Hohn
http://galan.sourceforge.net -- The graphical Audio language