//splits the current line into triangles.
//returns the number of triangles this line creates
int split_polygon(FILE *fp, jmesh *jm){
int nVerts;
static int which_tri=0;
int temp=fscanf(fp, "%d", &nVerts); //how many vertices do we have for this face?
if(temp != 1){
return -1;
}
//get the vertices
int verts[nVerts];
for(int i=0; i < nVerts; i++){
temp=fscanf(fp, "%d", &verts[i]);
if(temp != 1){
return -1;
}
}
//put these into triangles
for(int i=1; i < nVerts-1; i++, which_tri++){
*getV1(jm, which_tri) = verts[0];
*getV2(jm, which_tri) = verts[i];
*getV3(jm, which_tri) = verts[i+1];
}
return nVerts - 2;
}
bool Triangle::operator!=(const Triangle &t) const
{
if (t.getVector() == normal && t.getV1() == getV1() && t.getV2() == getV2()
&& t.getV3() == getV3())
return false;
return true;
}
//fills edges with two displacement vectors
//from face i
void get_edges(jmesh *jm, int i, float *edges){
float v1[3], v2[3], v3[3];
//get the xyz of each vertex of the triangle
v1[0] = *getX(jm, *getV1(jm, i));
v2[0] = *getX(jm, *getV2(jm, i));
v3[0] = *getX(jm, *getV3(jm, i));
v1[1] = *getY(jm, *getV1(jm, i));
v2[1] = *getY(jm, *getV2(jm, i));
v3[1] = *getY(jm, *getV3(jm, i));
v1[2] = *getZ(jm, *getV1(jm, i));
v2[2] = *getZ(jm, *getV2(jm, i));
v3[2] = *getZ(jm, *getV3(jm, i));
//compute V2-V1, V3-V1
edges[0] = v2[0]-v1[0];
edges[1] = v2[1]-v1[1];
edges[2] = v2[2]-v1[2];
edges[3] = v3[0]-v1[0];
edges[4] = v3[1]-v1[1];
edges[5] = v3[2]-v1[2];
}
