PhysX Implementation Questions

#61 OK I have to come right out and ask because this is getting to be a mess. Have you done this sweep test thing successfully, and do you even use the rigid collision anymore?

#62 It's not actually very difficult. It's one function. Look in the PhysX documents. You just call the function, it either returns a struct of some sort or you pass it one that it fills. It will have all the information of whether or not it got a hit. You'll use the "time" value to scale the position of the player, to move him back. You'll want to do this whereever it updates the player position in player.cpp. There is sample code for the sweep tests available.

#63 You might instead take a look at the character controller code that PhysX has. It has the full source code, so you can always make changes to it. There are also a couple of demos for it.

#64 Ok well I am starting this out.

void Vehicle::updatePos(F32 dt)
{
   Point3F origVelocity = mRigid.linVelocity;
   if (isServerObject())
   {
	   PhysXWorld *PxWorld = PhysXWorld::getWorld(isServerObject());
	   if (PxWorld) 
	   {
		   // const NxVec3 &motion = NxVec3(origVelocity.x, origVelocity.y, origVelocity.z);
		   NxU32 flags = NX_SF_STATICS|NX_SF_DYNAMICS;
		   NxSweepQueryHit result;
		   float dist = 100.0f;
		   NxVec3 dir(0.0f, -1.0f, 0.0f);
		   
		   mActor->actor->linearSweep(dir*dist, flags, NULL, 1, &result, NULL);
	   }
   }

Does this look about right to you?

I am assuming you mean the "t" variable member of NxSweepQueryHit is the time value you mentioned even though it says in the docs it is the distance to the hit.

Now finally, What do you mean scale the position of the object,? That is about the only thing I really have no idea what you mean.

#65 OK I have another question as I can see I had the option of adding more to the function which is the NxUserEntityReport which apparently calls a function for the closest object in the sweep. Did you use this?

#66 OK Ross I really need your help. I know now that I am extremely close with this but I am definitely handling the shape repositioning wrong because it is bounces madly and is nearly uncontrollable. However, I do know from the very few times I could contrl the vehicle enough to try to collide with the Triangle Mesh object I am using that it definitely detects it and reacts to it.

Here is my code. Please tell me what I have done wrong.

if (isServerObject())
   {
	   PhysXWorld *PxWorld = PhysXWorld::getWorld(isServerObject());
	   if (PxWorld) 
	   {
		   static NxF32 t = 0.0f;
		   NxF32 elapsedTime = dt;   
		   t += elapsedTime;

		   float dist = 100.0f;
		   NxVec3 dir(0.5f, -1.0f, 0.0f);
		   dir.normalize();

		   NxU32 flags = NX_SF_STATICS|NX_SF_DYNAMICS;
		   NxSweepQueryHit results[100];
		   
		   NxU32 nb = mActor->actor->linearSweep(dir*dist, flags, NULL, 100, results, NULL);
		   NxBox shapeBox;
		   if(nb)
		   {			   
			   mActor->actor->getShapes()[0]->isBox()->getWorldOBB(shapeBox);
			   shapeBox.center += results[0].t * dist * dir;
			   Point3F shapeCenter;
			   shapeCenter.set(shapeBox.center.x, shapeBox.center.y, shapeBox.center.z);
			   mRigid.linPosition = shapeCenter;
		   }
	   }
   }