9 replies to this topic

[Volgogradetzzz]

Hello. SAT excellent in finding TOI of convex NON rotating shapes. I wonder - is there any technique to predict collision for rotated bodies?

[owl]

http://www.gamedev.n...sion-detection/

This post in particular

[Volgogradetzzz]

Thanks, owl, but the question was not aboute SAT. For exaple I have 2 static bodies, i.e. their velocities is 0. But they can rotate and they can collide at some time. So how can I get this time?

[owl]

Thanks, owl, but the question was not aboute SAT. For exaple I have 2 static bodies, i.e. their velocities is 0. But they can rotate and they can collide at some time. So how can I get this time?

http://www.gamedev.net/topic/586690-collision-detection-for-rotating-objects/

the first reply pretty much addresses it.

[Volgogradetzzz]

Thanks. Sadly - but see the only way - decrease time steps.
Also I can do the following - given two line segments I can predict their TOI in current frame even if they moving with rotation. But math that I use - is toooooooooooo complicated - there're tons of sin/cos, so for real time sim with many objects this method is not suitable.

[owl]

I've read some moderator talking about radial swept-volumes (yet denoted as quite complicated). You might want to ask about that.. and post me back lol

[wildbunny]

I've read some moderator talking about radial swept-volumes (yet denoted as quite complicated). You might want to ask about that.. and post me back lol

You can use conservative advancement, or cheat and use closet points combined with speculative contacts - about half way through the article I talk about rotation

[Volgogradetzzz]

Yeah, I've read your article, but I'm true dummy and I didn't understand a half. I hope I'll dig it someday. Thanks.

[wildbunny]

Yeah, I've read your article, but I'm true dummy and I didn't understand a half. I hope I'll dig it someday. Thanks.

I've just published a new one on collision detection which covers continuous rotating bodies:

http://www.wildbunny.co.uk/blog/2011/04/20/collision-detection-for-dummies/


Hope its useful!

Cheers, Paul.

[Volgogradetzzz]

Oh, man, you're wonderful )))! Thanks.