Newton again...

[M109uk]

Hi,

I'm having some more trouble with newton,

I'm trying to get collision detection with particles, at the moment i want the particle to "die" when it collides with something other than another particle.

In my test app, i have a face along the XZ plane with the particle system above it, dropping like rain (see screenshot).
I have a newton debug rendering (the white boxes in the particles and on the face).


When the app is created, i create the scene (in which creates an empty newton world object) and a material object, i then create the face using NewtonCreateTreeCollision and set the world size around the face with a height of -200 - 200, i apply the scene's material id to the object.

When i create the particle, i use the newton box, and create a new material that is used on all the particles with in the particle group. I am not using any newton physics with the particles, instead i update the particles matrix and send it to newton.

I have collision callbacks set to the materials, however none of them are called when a particle collides with the face.

Initialize newton for the face:

var
  nColl: PNewtonCollision;
  i: Integer;
  v: Array [0..3] Of TVector3f;
  tmpM: Geometry.TMatrix4f;
  Min,Max: TVector3f;
begin
  nColl := NewtonCreateTreeCollision(_XScene.World, Nil);
  NewtonTreeCollisionBeginBuild(nColl);
  v[0] := Vertices[3].Point;
  v[1] := Vertices[2].Point;
  v[2] := Vertices[1].Point;
  v[3] := Vertices[0].Point;
  NewtonTreeCollisionAddFace(nColl, 4, @v[0], SizeOf(TVector3f), 1);
  NewtonTreeCollisionEndBuild(nColl, 0);

  If nColl = Nil Then Exit;
  _Body := NewtonCreateBody(_XScene.World, nColl);

  tmpM := MatrixTransform(Position, Rotation, Vector3fMake(1, 1, 1));
  NewtonBodySetMatrix(_Body, @tmpM[0, 0]);
  NewtonBodySetMaterialGroupID(_Body, _XScene.MaterialID);
  NewtonBodySetUserData(_Body, Self);

  NewtonCollisionCalculateAABB(nColl, @tmpM[0, 0], @Min[0], @Max[0]);

  If Min[0] > _XScene.WorldSize[0][0] Then _XScene.WorldSize[0][0] := Min[0];
  If Min[1] > _XScene.WorldSize[0][1] Then _XScene.WorldSize[0][1] := Min[1];
  If Min[2] > _XScene.WorldSize[0][2] Then _XScene.WorldSize[0][2] := Min[2];
  If Max[0] > _XScene.WorldSize[1][0] Then _XScene.WorldSize[1][0] := Max[0];
  If Max[0] > _XScene.WorldSize[1][1] Then _XScene.WorldSize[1][1] := Max[1];
  If Max[0] > _XScene.WorldSize[1][2] Then _XScene.WorldSize[1][2] := Max[2];
  _XScene.SetWorldSize;

  NewtonReleaseCollision(_XScene.World, nColl);
end;

Scene newton:

  fWorld := NewtonCreate(Nil, Nil);
// other code..
  DefaultID := NewtonMaterialGetDefaultGroupID(fWorld);
  fMaterialID := NewtonMaterialCreateGroupID(fWorld);
  NewtonMaterialSetDefaultFriction(fWorld, DefaultID, fMaterialID, 0.01, 0.01);
  NewtonMaterialSetDefaultElasticity(fWorld, DefaultID, fMaterialID, 0.01);

Particle Group:

  fMaterialID := NewtonMaterialCreateGroupID(_XScene.World);
  NewtonMaterialSetCollisionCallback(_XScene.World, _XScene.MaterialID, fMaterialID, @_XScene.MaterialID, @CollisionBegin, @CollisionWorld, Nil);
  NewtonMaterialSetCollisionCallback(_XScene.World, fMaterialID, fMaterialID, @fMaterialID, @CollisionBegin, @CollisionParticle, Nil);

On particle move:

    If (fParticles[Value].Body = Nil) And (fCollision) Then fParticles[Value].initNewton;
    If fParticles&#91;Value&#93;.Body <> Nil Then
    Begin
      tmpM &#58;= MatrixTransform&#40;fParticlePosition, Vector3fMake&#40;0, 0, 0&#41;, Vector3fMake&#40;1, 1, 1&#41;&#41;;
      NewtonBodySetMatrix&#40;fParticles&#91;Value&#93;.Body, @tmpM&#91;0, 0&#93;&#41;;
    End;

Particle initialize newton:

var
  nColl: PNewtonCollision;
  Position: TVector3f;
  maxSize: Single;
  tmpM: TMatrix4f;
begin
  If fBody <Nil> maxSize Then maxSize &#58;= TXParticleGroup&#40;fOwner&#41;.EndSize;

  Position &#58;= Vector3fMake&#40;TXParticleGroup&#40;fOwner&#41;.X, TXParticleGroup&#40;fOwner&#41;.Y, TXParticleGroup&#40;fOwner&#41;.Z&#41;;

  nColl &#58;= NewtonCreateBox&#40;_XScene.World, maxSize, maxSize, maxSize, Nil&#41;;
  fBody &#58;= NewtonCreateBody&#40;_XScene.World, nColl&#41;;
  NewtonReleaseCollision&#40;_XScene.World, nColl&#41;;

  tmpM &#58;= MatrixTransform&#40;Position, Vector3fMake&#40;0, 0, 0&#41;, Vector3fMake&#40;1, 1, 1&#41;&#41;;
  NewtonBodySetMatrix&#40;fBody, @tmpM&#91;0, 0&#93;&#41;;

  NewtonBodySetMaterialGroupID&#40;fBody, TXParticleGroup&#40;fOwner&#41;.MaterialID&#41;;
  NewtonBodySetUserData&#40;fBody, Self&#41;;
end;

Im uterly stuck on this, and from all the examples i have looked at i can't see anything wrong..

Many thanks