void SymmetryMod::ModifyTriObject (TimeValue t, ModContext &mc, TriObject *tobj, INode *inode) {
Mesh &mesh = tobj->GetMesh();
Interval iv = FOREVER;
int axis, slice, weld, flip;
float threshold;
mp_pblock->GetValue (kSymAxis, t, axis, iv);
mp_pblock->GetValue (kSymFlip, t, flip, iv);
mp_pblock->GetValue (kSymSlice, t, slice, iv);
mp_pblock->GetValue (kSymWeld, t, weld, iv);
mp_pblock->GetValue (kSymThreshold, t, threshold, iv);
if (threshold<0) threshold=0;
// Get transform from mirror controller:
Matrix3 tm = CompMatrix (t, NULL, &mc, &iv);
Matrix3 itm = Inverse (tm);
// Get DotProd(N,x)=offset plane definition from transform
Point3 Axis(0,0,0);
Axis[axis] = flip ? -1.0f : 1.0f;
Point3 origin = tm.GetTrans();
Point3 N = Normalize(tm*Axis - origin);
float offset = DotProd (N, origin);
// Slice operation does not handle NormalSpecs, but it handles mapping channels.
// move our mesh normal data to a map channel
MeshNormalSpec *pNormals = mesh.GetSpecifiedNormals ();
int normalMapChannel = INVALID_NORMALMAPCHANNEL;
if (pNormals && pNormals->GetNumFaces())
{
pNormals->SetParent(&mesh);
//find an empty map channel
for (int mp = 0; mp < mesh.getNumMaps(); mp++)
{
if (!mesh.mapSupport(mp))
{
normalMapChannel = mp;
mesh.setMapSupport(normalMapChannel,TRUE);
MeshMap& map = mesh.Map(normalMapChannel);
for (int i = 0; i < map.fnum; i++)
{
for (int j = 0; j < 3; j++)
{
unsigned int newID = pNormals->Face(i).GetNormalID(j);
map.tf[i].t[j] = newID;
}
}
map.setNumVerts(pNormals->GetNumNormals());
for (int i = 0; i < map.vnum; i++)
{
map.tv[i] = pNormals->Normal(i);
}
// make sure nothing is done with MeshNormalSpec (until data is copied back)
pNormals->Clear();
break;
}
}
}
// Slice off everything below the plane.
if (slice) SliceTriObject (mesh, N, offset);
MirrorTriObject (mesh, axis, tm, itm,normalMapChannel);
if (weld) WeldTriObject (mesh, N, offset, threshold);
//now move the normals back
if (pNormals && normalMapChannel != -1)
{
MeshMap& map = mesh.Map(normalMapChannel);
pNormals->SetNumFaces(map.fnum);
pNormals->SetNumNormals(map.vnum);
pNormals->SetAllExplicit(true);
BitArray temp;
temp.SetSize(map.vnum);
temp.SetAll();
pNormals->SpecifyNormals(TRUE,&temp);
for (int i = 0; i < map.vnum; i++)
{
pNormals->GetNormalArray()[i] = map.tv[i];
pNormals->SetNormalExplicit(i,true);
}
for (int i = 0; i < map.fnum; i++)
{
for (int j = 0; j < 3; j++)
{
pNormals->SetNormalIndex(i,j,map.tf[i].t[j]);
MeshNormalFace& face = pNormals->Face(i);
face.SpecifyAll(true);
}
}
pNormals->SetFlag(MESH_NORMAL_MODIFIER_SUPPORT);
for (int i = 0; i < pNormals->GetNumFaces(); i++)
{
for (int j = 0; j < 3; j++)
{
int id = pNormals->GetNormalIndex(i,j);
}
}
pNormals->CheckNormals();
pNormals->SetParent(NULL);
// Free the map channel
mesh.setMapSupport(normalMapChannel,FALSE);
}
tobj->UpdateValidity (GEOM_CHAN_NUM, iv);
tobj->UpdateValidity (TOPO_CHAN_NUM, iv);
tobj->UpdateValidity (VERT_COLOR_CHAN_NUM, iv);
tobj->UpdateValidity (TEXMAP_CHAN_NUM, iv);
tobj->UpdateValidity (SELECT_CHAN_NUM, iv);
}
