Best way of handling simultaneous collision detection for numerous characters?

[kestrel]

Hello,

I'm contemplating a situation where 50+ characters will be moving around in the same room, and was wondering if anyone could suggest super-efficient methods for handling the resulting collision detection.

Up to now I've used two interlocked character counts and an (AreThingOverlapping(firstcount,secondcount)) check to deal with things, but am wondering if this approach will be up to the task with extremely high character headcounts (I already suspect some collisions are slipping through the net because of the time it takes to run through the counts).

All suggestions welcome.

Thanks,
kestrel 

[Kweepa]

For an (incomplete) shootemup I did some work on, the collision detection was handled by rendering objects into a low resolution buffer, using a different colour for each object. Then to check for collision, the bullets just picked the colour in the centre of the bullet, and the player ship scanned the ship's outline.
You might be able to do something similar, depending on the size of the characters.

[kestrel]

Thanks Kweepa. Interesting concept. Creating a low-res buffer isn't something I've ever tried; I'll do some forum searches/experimenting.