[ODE] auto-enable problem solutions?

[Jani Laakso]

Aras Pranckevicius wrote:

> Now, for auto-disabling to be really effective, you have to take some care
> 
> // -----------------
> static void nearCallback (void *data, dGeomID o1, dGeomID o2) {

I'm using pretty similar case with Odejava:

  // ignore if both o1 and o2 are plain Geoms (not bodies)
   if (!b1 && !b2) return;

   // check more if both are bodies
   if (b1 && b2) {
     // A body collides with body

     // ignore if both bodies are connected by a joint
     if (dAreConnectedExcluding (b1,b2,dJointTypeContact)) return;

     // ignore if both bodies are disabled
     if (!dBodyIsEnabled(b1) && !dBodyIsEnabled(b2)) return;
   } else {
     // A body collides with geom

     // ignore if disabled body collides with plain geom
     if (b1 && !dBodyIsEnabled(b1)) return;
     if (b2 && !dBodyIsEnabled(b2)) return;
   }

Have you made anything (or got any ideas) for the re-enable problem? 
This auto disabling is good feature bust as someone earlier already 
stated it has it's problems.

If I construct e.g. high tower and set it disabled by default and then 
slowly push the lowest box somewhat ahead, then some boxes are left 
floating in the air, upper boxes are not re-enabled because no contacts 
occur with the enabled lower boxes.

Solutions

1. extend a reenabled body's AABB a little, and checking
which disabled bodies' AABBs are now intersecting, then re-enabling 
those (comment from ql at ntlworld.com)

2. same than upper but temporarily expand the raw geom's dimensions 
(comment from adam)

Upper solutions needs changing the ODE internals and checking this can 
take too much of my time.

Does anyone have any other ideas?

-- 
Jani Laakso / IT Mill Ltd | Tel. +358 40 5898086 | http://www.itmill.com