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Modified: Tutte weights initialization for inner border vertices with valency-2. However such vertices can affect optimization.

This commit is contained in:
Hardik Jain 2020-03-28 16:26:56 +01:00 committed by hrdkjain@cordelia-ubuntu
parent c3da7a2201
commit ee9fcee717
1 changed files with 44 additions and 38 deletions
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82
Surface_mesh_parameterization/include/CGAL/Surface_mesh_parameterization/Iterative_authalic_parameterizer_3.h
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@ -234,53 +234,59 @@ protected:
neighborsCounter++; neighborsCounter++;
} }
// compute angles
for(int n=0; n<neighborsCounter; n++) {
int n_prev = (n==0 ? neighborsCounter-1 : n-1);
double theta = angle(NeighborList_[n].vector,NeighborList_[n_prev].vector);
NeighborList_[n].angle = theta;
theta_sum += theta;
}
// Normalise the angle
double factor = 2.0 / theta_sum;
factor *= M_PI;
for(int n=0; n<neighborsCounter; n++)
NeighborList_[n].angle *= factor;
NeighborList_[0].angle = 0.0;
for(int n=1; n<neighborsCounter; n++)
NeighborList_[n].angle += NeighborList_[n-1].angle;
for(int n=0; n<neighborsCounter; n++)
NeighborList_[n].uv = Point_2(NeighborList_[n].length*cos(NeighborList_[n].angle), NeighborList_[n].length*sin(NeighborList_[n].angle));
if (neighborsCounter < 2) if (neighborsCounter < 2)
return ERROR_NON_TRIANGULAR_MESH; return ERROR_NON_TRIANGULAR_MESH;
if(neighborsCounter==2 && mesh.is_border(vertex)) {
std::cout << "Encountered inner border with valency-2 vertex (" << vertex << "), initializing with Tutte weights, this can affect optimization" << std::endl;
// Tutte weights
for(int k=0; k<neighborsCounter; k++)
NeighborList_[k].weight = 1.0;
}
else {
for(int n=0; n<neighborsCounter; n++) {
int n_prev = (n==0 ? neighborsCounter-1 : n-1);
double theta = angle(NeighborList_[n].vector,NeighborList_[n_prev].vector);
NeighborList_[n].angle = theta;
theta_sum += theta;
}
for(int j=0; j<neighborsCounter; j++) // Normalise the angle
{ double factor = 2.0 / theta_sum;
/* Given the j-th neighbour of node i, factor *= M_PI;
for(int n=0; n<neighborsCounter; n++)
NeighborList_[n].angle *= factor;
NeighborList_[0].angle = 0.0;
for(int n=1; n<neighborsCounter; n++)
NeighborList_[n].angle += NeighborList_[n-1].angle;
for(int n=0; n<neighborsCounter; n++)
NeighborList_[n].uv = Point_2(NeighborList_[n].length*cos(NeighborList_[n].angle), NeighborList_[n].length*sin(NeighborList_[n].angle));
for(int j=0; j<neighborsCounter; j++)
{
/* Given the j-th neighbour of node i,
find the two neighbours by intersecting the find the two neighbours by intersecting the
line through nodes i and j with all segments of the polygon line through nodes i and j with all segments of the polygon
made by the neighbours. Take the two neighbours on made by the neighbours. Take the two neighbours on
either side. Only one segment intersects this line. */ either side. Only one segment intersects this line. */
for(int k=0; k<neighborsCounter; k++) for(int k=0; k<neighborsCounter; k++)
{
int kk = (k == neighborsCounter-1 ? 0 : k+1);
if(k == j || kk == j) continue;
double cross1 = determinant(NeighborList_[j].uv,NeighborList_[k].uv);
double cross2 = determinant(NeighborList_[j].uv,NeighborList_[kk].uv);
if(cross1 * cross2 <= 0.0)
{ {
double tau0,tau1,tau2; int kk = (k == neighborsCounter-1 ? 0 : k+1);
baryCoords0(NeighborList_[j].uv, NeighborList_[k].uv, NeighborList_[kk].uv, tau0, tau1, tau2); if(k == j || kk == j) continue;
NeighborList_[j].weight += tau0;
NeighborList_[k].weight += tau1; double cross1 = determinant(NeighborList_[j].uv,NeighborList_[k].uv);
NeighborList_[kk].weight += tau2; double cross2 = determinant(NeighborList_[j].uv,NeighborList_[kk].uv);
break;
if(cross1 * cross2 <= 0.0)
{
double tau0,tau1,tau2;
baryCoords0(NeighborList_[j].uv, NeighborList_[k].uv, NeighborList_[kk].uv, tau0, tau1, tau2);
NeighborList_[j].weight += tau0;
NeighborList_[k].weight += tau1;
NeighborList_[kk].weight += tau2;
break;
}
} }
} }
} }