Collision between 2 balls

Serg Nechaeff · Post by **Serg Nechaeff** » Thu Dec 04, 2003 4:17 pm

I have 2 balls (3ds models) how can I detect when they touch each other? I have them in 2 different nodes... Thnx in advance!

Serg Nechaeff · Post by **Serg Nechaeff** » Thu Dec 04, 2003 5:30 pm

Maybe I have to calculate the distance between their centres?

stampsm · Post by **stampsm** » Thu Dec 04, 2003 10:00 pm

possibly that can be a cheep form of colition detection
did you read all of the tutorials one of them talked about colition detection

Masdus · Post by **Masdus** » Fri Dec 05, 2003 12:07 am

I believe only static collision detection is implemented so far. This enables detection of a model colliding with the map, but not with two moving models. You may want to see about implementing a 3rd party library for detection if you can't wait for a this feature to be implemented

Serg Nechaeff · Post by **Serg Nechaeff** » Fri Dec 05, 2003 12:37 am

oh... it sucks! i wanted to finish my game in 2 days, it complicates things a bit... probably will go with radius vectors or smth :-/

Masdus · Post by **Masdus** » Thu Dec 11, 2003 2:11 am

another options is to use ODE oe Tokamak physics engines, there are tuts on the irrlicht page on how to intergrate them with the engine

Guest · Post by **Guest** » Thu Dec 11, 2003 3:06 pm

The solution is sooo simply : Calculate the distance between the centers of your balls. That is dist = ball2_pos - ball1_pos. Add the radius' of the two balls and compare it to the distance. rad = ball1_rad + ball2_rad;

if (dist > rad) --> not colliding
if (dist == rad) --> touching
if (dist < rad) --> intersecting each other

To calculate co-called "dynamic" collision detection, simply advance one frame and test for collision. If they collide, un-do your move ! It's as easy as that...

Serg Nechaeff · Post by **Serg Nechaeff** » Fri Dec 12, 2003 4:21 am

yeah, thanks, i did that already

another solution is to use bounding box collisions

Isometric God · Post by **Isometric God** » Sun Dec 14, 2003 1:35 am

Oups... the guest was me