DelaunayEffect(NewtonWorld* const world, NewtonMesh* const mesh, int interiorMaterial)
:FractureEffect(world)
{
// first we populate the bounding Box area with few random point to get some interior subdivisions.
// the subdivision are local to the point placement, by placing these points visual ally with a 3d tool
// and have precise control of how the debris are created.
// the number of pieces is equal to the number of point inside the Mesh plus the number of point on the mesh
dVector size(0.0f);
dMatrix matrix(dGetIdentityMatrix());
NewtonMeshCalculateOOBB(mesh, &matrix[0][0], &size.m_x, &size.m_y, &size.m_z);
// create a texture matrix, for applying the material's UV to all internal faces
dMatrix textureMatrix(dGetIdentityMatrix());
textureMatrix[0][0] = 1.0f / size.m_x;
textureMatrix[1][1] = 1.0f / size.m_y;
// Get the volume of the original mesh
NewtonCollision* const collision1 = NewtonCreateConvexHullFromMesh(m_world, mesh, 0.0f, 0);
dFloat volume = NewtonConvexCollisionCalculateVolume(collision1);
NewtonDestroyCollision(collision1);
// now we call create we decompose the mesh into several convex pieces
NewtonMesh* const debriMeshPieces = NewtonMeshCreateTetrahedraIsoSurface(mesh);
dAssert(debriMeshPieces);
// now we iterate over each pieces and for each one we create a visual entity and a rigid body
NewtonMesh* nextDebri;
for (NewtonMesh* debri = NewtonMeshCreateFirstLayer(debriMeshPieces); debri; debri = nextDebri) {
// get next segment piece
nextDebri = NewtonMeshCreateNextLayer(debriMeshPieces, debri);
//clip the Delaunay convexes against the mesh, make a convex hull collision shape
NewtonCollision* const collision = NewtonCreateConvexHullFromMesh(m_world, debri, 0.0f, 0);
if (collision) {
// we have a piece which has a convex collision representation, add that to the list
FractureAtom& atom = Append()->GetInfo();
atom.m_mesh = new DemoMesh(debri);
atom.m_collision = collision;
NewtonConvexCollisionCalculateInertialMatrix(atom.m_collision, &atom.m_momentOfInirtia[0], &atom.m_centerOfMass[0]);
dFloat debriVolume = NewtonConvexCollisionCalculateVolume(atom.m_collision);
atom.m_massFraction = debriVolume / volume;
}
NewtonMeshDestroy(debri);
}
NewtonMeshDestroy(debriMeshPieces);
}
void CreateTetrahedraPrimitive(DemoEntityManager* const scene, int materialID)
{
dFloat mass = 5.0f;
dVector size (1.0f);
NewtonWorld* const world = scene->GetNewton();
NewtonCollision* const primitiveShape = CreateConvexCollision (world, dGetIdentityMatrix(), size, _SPHERE_PRIMITIVE, materialID);
//NewtonCollision* const primitiveShape = CreateConvexCollision (world, dGetIdentityMatrix(), size, _BOX_PRIMITIVE, materialID);
NewtonMesh* const skinMesh = NewtonMeshCreateFromCollision(primitiveShape);
dMatrix aligmentUV(dGetIdentityMatrix());
int material = LoadTexture("smilli.tga");
NewtonMeshApplySphericalMapping(skinMesh, material, &aligmentUV[0][0]);
// now now make an tetrahedra iso surface approximation of this mesh
NewtonMesh* const tetraIsoSurface = NewtonMeshCreateTetrahedraIsoSurface(skinMesh);
// calculate the linear blend weight for the tetrahedra mesh
NewtonCreateTetrahedraLinearBlendSkinWeightsChannel (tetraIsoSurface, skinMesh);
NewtonDestroyCollision(primitiveShape);
// make a deformable collision mesh
NewtonCollision* const deformableCollision = NewtonCreateDeformableSolid(world, tetraIsoSurface, materialID);
//create a rigid body with a deformable mesh
m_body = CreateRigidBody(scene, mass, deformableCollision);
// create the soft body mesh
//DemoMesh* const mesh = new TetrahedraSoftMesh(tetraIsoSurface, m_body);
DemoMesh* const mesh = new LinearBlendMeshTetra(scene, skinMesh, m_body);
SetMesh(mesh, dGetIdentityMatrix());
// do not forget to destroy this objects, else you get bad memory leaks.
mesh->Release ();
NewtonMeshDestroy(skinMesh);
NewtonDestroyCollision(deformableCollision);
NewtonMeshDestroy(tetraIsoSurface);
}
