ODE-TIDBITS

/*

Here is code to use ODE to ray cast from an irrlicht scene node object. Useful for shooting and as a turn sensor. I assume you alredy have the the Irrlicht ODE tutorial working. scenenode is the node that you want to cast a ray from, Geom is the ODE geometry attached to the scenenode, Body is the ODE body attached to the scene node, and space is the collision space.

Code:
*/

dGeomID ray = dCreateRay(Space,1000);
bPos = scenenode->getAbsolutePosition();
const dReal *r;
r = dBodyGetRotation(Body);
dGeomSetRotation (ray,r);
dGeomSetPosition (ray,bPos.X, bPos.Y, bPos.Z);

dContactGeom contact;
dGeomRaySetLength (ray,1000);
int num = dSpaceGetNumGeoms(Space);
for (int ii=0; ii<num; ++ii) {
   dGeomID geo = dSpaceGetGeom(Space,ii);
   if ( dGeomGetClass( geo ) == dSphereClass || dGeomGetClass( geo ) == dBoxClass ){
      if (geo != Geom) {
         if ( dCollide( ray, geo, 1, &contact, sizeof(contact) ) ){
            cout << "contact with object at co-ord : " << endl;
            const dReal *tPos  = dGeomGetPosition (geo);
            cout << "x" << tPos[0] << "; y" << tPos[1] << "; z" << tPos[2] << endl;
         }
      }
   }
}
dSpaceRemove( Space, ray );
dGeomDestroy( ray );