public void setNormals() {
// first get normals for all faces
int numFaces = F.size();
for (Face f : F) {
Edge e = E.get(f.e);
Vec3 v1 = V.get(e.v).coord;
e = E.get(e.next);
Vec3 v2 = V.get(e.v).coord;
e = E.get(e.next);
Vec3 v3 = V.get(e.v).coord;
// set the normal for this face
Vec3 U = Vec3.sub(v2, v1);
Vec3 V = Vec3.sub(v3, v1);
float nx = U.y * V.z - U.z * V.y;
float ny = U.z * V.x - U.x * V.z;
float nz = U.x * V.y - U.y * V.x;
f.norm = new Vec3(nx, ny, nz);
f.norm.normalize();
}
// next set normals for all vertices
for (Vert v : V) {
Vector<Vec3> norms = new Vector<Vec3>();
Edge e = E.get(v.e);
Edge eNext = e; // E.get(E.get(e.sym).next);
do {
// get eNext's Face's norm and store it for combining later
norms.add(F.get(eNext.f).norm);
eNext = E.get(E.get(eNext.sym).next);
} while (e.i != eNext.i);
// combine scaled norms here and set v.norm
float scale = 1.0f / norms.size();
Vec3 vNorm = new Vec3(0, 0, 0);
for (int i = 0; i < norms.size(); i++)
vNorm = Vec3.add(vNorm, norms.get(i)); // .scale(scale));
v.norm = vNorm;
v.norm.normalize();
}
}
protected void splitEdge(int e, Vec3 newPos) {
Edge edge = E.get(e);
Edge sym = E.get(edge.sym);
Edge e0 = new Edge();
Edge e1 = new Edge();
Vert v0 = new Vert();
// set indices of new edges + vert
e0.i = E.size();
e1.i = e0.i + 1;
// set up v0
v0.coord = newPos;
v0.i = V.size();
v0.e = e0.i;
V.add(v0);
// set up e0
e0.v = v0.i;
e0.f = edge.f;
e0.next = edge.next;
e0.prev = edge.i;
e0.sym = edge.sym;
// set up e1
e1.v = v0.i;
e1.f = sym.f;
e1.next = sym.next;
e1.prev = edge.sym;
e1.sym = edge.i;
E.add(e0);
E.add(e1);
// clean up connections with e and e.sym
E.get(edge.next).prev = e0.i;
E.get(sym.next).prev = e1.i;
edge.next = e0.i;
sym.next = e1.i;
sym.sym = e0.i;
edge.sym = e1.i;
}
public Mesh(Vec3 verts[], int faces[][]) {
V = new Vector<Vert>(verts.length);
for (int i = 0; i < verts.length; i++) V.addElement(null);
F = new Vector<Face>(faces.length);
for (int i = 0; i < faces.length; i++) F.addElement(null);
int numEdges = 0;
for (int f = 0; f < faces.length; f++) numEdges += faces[f].length;
E = new Vector<Edge>(numEdges);
for (int i = 0; i < numEdges; i++) E.addElement(null);
originalFaceVerts = new Vector<Integer>(faces.length);
originalFaceEdges = new Vector<Integer>(faces.length);
Hashtable<IntPair, Edge> edgeTable = new Hashtable<IntPair, Edge>();
int ei = 0; // base index for group of edges for next face
for (int f = 0; f < faces.length; f++) {
int[] face = faces[f]; // current face
final int N = face.length; // number of edges in face
for (int i = 0; i < N; i++) {
Edge edge = new Edge();
edge.i = ei + i;
final int v = face[i];
final int vnext = face[(i + 1) % N];
IntPair key = new IntPair(vnext, v);
Edge sym = edgeTable.get(key);
if (sym == null) {
key = new IntPair(v, vnext);
edgeTable.put(key, edge);
} else {
edge.sym = sym.i;
sym.sym = ei + i;
}
edge.v = v;
if (V.get(v) == null) {
Vert wvert = new Vert();
wvert.i = v;
wvert.e = edge.i;
wvert.coord = new Vec3(verts[v]);
V.set(v, wvert);
}
edge.f = f;
edge.next = ei + (i + 1) % N;
edge.prev = ei + (i + N - 1) % N;
E.set(edge.i, edge);
}
Face wface = new Face();
wface.i = f;
wface.e = ei;
F.set(f, wface);
ei += N;
}
// ensure mesh is triangular
triangulate();
// get number of original faces
originalFaceCount = F.size();
// get one of each original face's vertices
for (int i = 0; i < originalFaceCount; i++) originalFaceVerts.add(E.get(F.get(i).e).v);
for (int i = 0; i < originalFaceCount; i++) originalFaceEdges.add(F.get(i).e);
// set the normals for the mesh
setNormals();
}
protected void adjustEvenVerts(Hashtable<Integer, Vec3> evenVerts) {
for (int i = 0; i < V.size(); i++) {
Vert v = V.get(i);
v.coord = evenVerts.get(v.i);
}
}