drawing a simple point or line

[Brandon <bmccombs ma rr com>]

what are the widget types and functions that i would need in order to
draw points or lines in a gtk drawing area w/o having to rely on a
signal being emitted in order to call a function that would do the
drawing? I followed a tutorial and I was able to get drawing to work
within the functions that listen for the "configure" and "expose"
signals but I want points to be drawn as my program is performing
calculations (to plot values) and therefore I'm not listening for
signals. But I cant get the code to work even though im using the same
1st argument to the gdk_draw_point() function as I do when it's used in
the function that is called when the "configure" signal is emitted. I'm
given an error related to the widget I use as the first argument saying
that "assertion 'drawable' != NULL" failed. I'm declaring "drawable" to
be a GtkWidget.


What's the difference that I'm missing betweeen drawing in a function
after a signal and drawing in main() whenever I feel like it?



thanks
Brandon