Hi Peter:
Thanks for the explanation and example.
Ya, I have only start to understand the way Gem/OpenGL works in terms of gemlist and so on. I have also tried to draw trails or repeated motions with [any] but did not get anywhere with it. Your example will be a good starting point for me.
However, a Gem delay line object could be very interesting.
Thanks again
CHUN
On 8/12/04 4:36 pm, "Peter Todd" peter_todd82@yahoo.co.uk wrote:
I would like to draw the trail of a geo in motion, how can I do this? I am thinking of delay the gemlist to the specified amount but having no luck in doing so.
I have wondered a bit about individual geos leaving trails, and delay line type things, but I haven't reached much conclussion (or done much experimentation). You could use a table to store the previous frames data, and have diminishing alpha for older elements, but again it would be far from perfect. Could be workable, though. I might see what I can hack together this afternoon, otherwise it won't be for a few days. As far as a generalised 'delay line' goes, I think this could turn out to be a good approach.
Here's a start.