why havok's collision detection not so exact

why havok's collision detection not so exact

In vdb, I take a collision detection test with two simple boxes, when I move a box to be closed to another box(but not touch), these two boxes collide, but I don't know why and how to do?somebody help me:-

6 posts / 0 new
Last post
For more complete information about compiler optimizations, see our Optimization Notice.

Now I know, my collision detection test is base on midphase, but I dont know how to set the cinfo(maybe others), so I did not solve it yet?

havokchrisk's picture
Best Reply

Hey 205dsm126.com,

It sounds like you might have your 'Midphase' viewer enabled... do you also have the 'Shapes' viewer enabled? I might recommend enabling the 'Shapes' viewer as well as the 'Convex Radius' viewer, since the effective collision shape used for contact point generation will include this radius as well... this might explain a collision even if the actual shapes themselves aren't penetrating.

Chris

Developer Support Engineer
Havok
www.havok.com

Hi havokchrisk,

Thank you, Now I have my 'Shapes' viewer and 'Convex Radius' viewer enabled, and the collision is correct now. My boxes's side length is short, so the 'Convex Radius' viewer looks deep. what can I do if I want to make the 'Convex Radius' viewer's boundingbox thinner. I have tried to set:
worldInfo.m_collisionTolerance = 0.00001f;
but it did not change anything. Can the 'Convex Radius' be setted a small value?

:-)

havokchrisk's picture

You can set the collision shape's convex radius through hkpConvexShape::setRadius()... that should get you the behavior you're looking for. The world collision tolerance determines when contact points will begin being generated/cached for shapes (for things like stabilizing collisions), so this setting probably won't affect the collisions that you are seeing in this case.

Chris

Developer Support Engineer
Havok
www.havok.com

Thank you very much!

Login to leave a comment.