Sample video here:
http://www.youtube.com/user/steffensensa#p/a/u/0/qX7xoOEyJMM
Hi,
I've been wanting to have Nvidia Physx in my projects for a long time,
so I was finally able to do so, for now it's really simple, I press a button to add cubes to my scene,
which get's their transformation and rotation from the physx objects.
Please note that I ported this straight from a openGL example, and there are probably many other way's of doing this.
I just wanted it "to work" and start from there, and I'm no guru, so don't expect it to be perfect.
But I've got to start somewhere. 
This is how I did it:
Go and download 'Physx candy wrapper' from here
get the mogrephysx dll, and add it as reference to your project.
Variables. these goes in top of your class:
[code]
protected const long tickspersec = 10000000;
protected static long lasttickcount;
protected static double t = 0;
protected static double dt = 0;
protected Scene phscene;
protected bool StartToUpdatePhysx = false;
protected Physics physics;
private int PhysxBoxCount = 1;
private int tempCounter = 1;
int linecount = 1;
[/code]
Next step is to create your physx scene, to put physx objects into:
I also connect to the 'physx debugger' to make life easier.
Just call this one while creating your scene.
[code]
protected void Initphysx()
{
//"Start" physx
var physics = Physics.Create();
//Set the skin widht.
physics.Parameters.SkinWidth = 0.002F;
//Create a new physx scene
phscene = physics.CreateScene( new SceneDesc() );
//set the max timestep
phscene.Timing.MaxTimestep = 1.0f / (3 * 24);
//set gravity in physx
phscene.Gravity = new Mogre.Vector3( 0, -9.81f, 0 );
//Create a material defining properties for the physx objects
var defm = phscene.Materials[0];
defm.Restitution = 0.5f;
defm.DynamicFriction = defm.StaticFriction = 10.6f;
//Connect to the debugger.
physics.RemoteDebugger.Connect("localhost");
}
[/code]
Spawning boxes:
[code]
public void Spawncube()
{
//make a vector variable named pos.
Vector3 pos = new Mogre.Vector3(0, 0, 0);
float tempy = pos.y;
//this is where we spawn boxes in our scene
pos.x = 0;
pos.y = 1000;
pos.z = 0;
//Create a physx ground plane
phscene.CreateActor(new ActorDesc(new PlaneShapeDesc()));
//Create a new box in physx
var ad = new ActorDesc(new BodyDesc(), 1, new BoxShapeDesc(new Vector3(1, 1, 1)));
//Set it's position to spawnpoint
ad.GlobalPosition = pos;
//Create the physx actor and give it a name
var a = phscene.CreateActor(ad);
a.Name = "Actor_" + PhysxBoxCount;
//Here we create the mogre entity and give it the same name as the physx object
var planeEnt = sceneMgr.CreateEntity( ("Actor_" + PhysxBoxCount) , SceneManager.PrefabType.PT_CUBE);
var physxnodew = sceneMgr.CreateSceneNode("Actor_" + PhysxBoxCount);
physxnodew.AttachObject(planeEnt);
physxnodew._update(true, true);
PhysxBoxCount += 1;
//Scale the object down a bit
planeEnt.ParentSceneNode.Scale(0.2f, 0.2f, 0.2f);
// this one is to enable us to start it when the objects are created.
if (!StartToUpdatePhysx)
{
StartToUpdatePhysx = true;
}
return;
}
[/code]
Now we need a update loop.. this is done like this:
Add these two functions, and add to the "on each frame" loop,
there you add the "onidle" function.
[code]
//Call this one (OnIdle) on each frame.
private void OnIdle()
{
System.Threading.Thread.Sleep( 1 );
long ticks = DateTime.Now.Ticks;
if ( lasttickcount == 0 ) lasttickcount = ticks;
long tickselapsed = ticks - lasttickcount;
lasttickcount = ticks;
dt = (double)tickselapsed / tickspersec;
t += dt;
OnFrame();
}
protected virtual void OnFrame()
{
System.Threading.Thread.Sleep( 1 );
phscene.Simulate(1.0);
phscene.Simulate( dt );
phscene.FlushStream();
phscene.FetchResults( SimulationStatuses.AllFinished, true );
}
[/code]
Updating the translation \ rotation of all the objects:
Call this one per frame.
[code]
protected void UpdatePhysics()
{
foreach (var a in phscene.Actors)
{
if (!a.IsDynamic) continue;
if (StartToUpdatePhysx)
{
if (sceneMgr.HasSceneNode(a.Name))
{
var mat = a.GlobalPose;
var rot = a.GlobalOrientationQuaternion;
var tempnode = sceneMgr.GetSceneNode(a.Name);
tempnode.Orientation = rot;
tempnode.Position = mat.GetTrans();
}
}
}
}
[/code]
