[XForms] Colour picker

[jon]

I see lots of demos in xforms but I can't find anything I can use as a
colour picker.

I've created a form and loaded up a graphic with:

    obj = fl_add_pixmap( FL_NORMAL_PIXMAP, 50, 40, 450, 450, "" );
    fl_set_pixmap_file( obj, "conic-spectrum1.xpm" );

But I am not sure how I can read an RGB value from under the cursor. I
need the raw RGB value not the closest forms colour.

Some combination of XGetPixel and the mouse position might do the job
but I am unsure how to combine Xlib stuff with Xforms objects in any
useful way.

Does anyone have an example that might help.

Thanks,
Jon