Collision problem

[Dave]

Hi - I am having trouble with viewpoint collision. I have a very large mesh that is a landscape and in a few places I have smaller separate models overlying the mesh that are more detailed areas.

The viewpoint flies over the landscape and is prevented from descending below a fixed level except when it is above the more detailed models where I would like it to go lower but collide with the ground and not go through it.

<viewpoint>.collision( viz.ON ) does actually work but the problem is that the 'flythrough' judders to a crawl - presumably because the viewpoint needs to check whether it is going to collide with every node in the large landscape.

I had hoped that collideMesh applied to the smaller models would cause the viewpoint to collide just with those models but try as I might I cannot get the viewpoint to collide with anything in this way.

I presume that collideMesh, collideBox etc only operate between objects and not a viewpoint and an object. Is there any way to make the viewpoint collide with the surface of a single object within a scene?

Any ideas will be very much appreciated.

Thanks

Dave

[Jeff]

As you guessed, collision shapes work between objects and not the viewpoint. You can turn on viewpoint collision and disable it for certain models. The following example disables viewpoint collision with the court but not the box:

import viz
viz.go()

viz.collision(viz.ON)

court = viz.add('court.ive')
court.disable(viz.INTERSECTION)

box = viz.add('box.wrl',pos = [0,1.5,5])

[Dave]

Thanks Jeff - that works fine. I did have a problem in that due to the scaling that I had used the viewpoint did not seem to be able to get close enough to the ground (I guess there is a lower limit for the buffer size) but this was ok when I scaled everything up by a factor of 20. Thanks again.