Making things flash...

Wouter de Waal (
Tue, 17 Dec 1996 18:19:19 +0200

To subscribers of the xforms list from (Wouter de Waal) :

Hi all

I want to have a flashing red spot or two on the screen. But I don't
specifically want to redraw everything every time. So I thought of changing
the color pointed to by FL_FREE_COL1 every now & then, using a timer.

OK, first try:

fl_mapcolor(FL_FREE_COL1, red, green, blue)

This only works (the change in color is only accepted) when the form (or I
assume the object) is redrawn. Not good.

OK, second try:


where xcolor.pixel = fl_get_pixel(FL_FREE_COL1)

and I get an X error, BadAccess, this is a Private Resource.

So, what do I try next? Has anybody done something like this? Ideally, I
would like to map a flashing red, green and blue, say, to FL_FREE_COLx, i.e.
every second timer tick I would map FL_COL1 into there and every other tick
it would be FL_RED or FL_GREEN.



Wouter de Waal        Phone : +27 21 683 5490
Development Engineer  Fax   : +27 21 683 5435
CCII Systems
Kenilworth, South Africa