void VisusIndexedData::computeVertexNormals()
{
uint32_t i,j;
std::vector<IndexDataType>& poly = element(0);
std::vector<VertexDataType> n;
VertexDataType w;
// First we reset all normals to 0
for (i=0;i<nrOfVertices();i++) {
(*mVertices)[i][3] = 0;
(*mVertices)[i][4] = 0;
(*mVertices)[i][5] = 0;
}
// For each element we add the normal components weighted by
// interior angle
for (i=0;i<nrOfElements();i++) {
poly = element(i);
n = weightedNormal(vertex(poly.back()),vertex(poly[0]),vertex(poly[1]));
(*mVertices)[poly[0]][3] += n[0];
(*mVertices)[poly[0]][4] += n[1];
(*mVertices)[poly[0]][5] += n[2];
for (j=1;j<poly.size()-1;j++) {
n = weightedNormal(vertex(poly[j-1]),vertex(poly[j]),vertex(poly[j+1]));
(*mVertices)[poly[j]][3] += n[0];
(*mVertices)[poly[j]][4] += n[1];
(*mVertices)[poly[j]][5] += n[2];
}
n = weightedNormal(vertex(poly[poly.size()-2]),vertex(poly.back()),vertex(poly[0]));
(*mVertices)[poly.back()][3] += n[0];
(*mVertices)[poly.back()][4] += n[1];
(*mVertices)[poly.back()][5] += n[2];
}
for (i=0;i<nrOfVertices();i++) {
w = vertex(i)[3]*vertex(i)[3] + vertex(i)[4]*vertex(i)[4] + vertex(i)[5]*vertex(i)[5];
if (w > 10e-8) {
w = 1/sqrt(w);
//fprintf(stderr,"weight %f\n",w);
(*mVertices)[i][3] *= -w;
(*mVertices)[i][4] *= -w;
(*mVertices)[i][5] *= -w;
}
else {
(*mVertices)[i][3] = 0;
(*mVertices)[i][4] = 0;
(*mVertices)[i][5] = -1;
}
//fprintf(stderr,"Normal %f %f %f \n",(*mVertices)[i][3],(*mVertices)[i][4],(*mVertices)[i][5]);
}
}
void MD5Surface::buildVertexNormals()
{
for (Indices::iterator j = _indices.begin(); j != _indices.end(); j += 3)
{
ArbitraryMeshVertex& a = _vertices[*(j + 0)];
ArbitraryMeshVertex& b = _vertices[*(j + 1)];
ArbitraryMeshVertex& c = _vertices[*(j + 2)];
Vector3 weightedNormal((c.vertex - a.vertex).crossProduct(b.vertex - a.vertex));
a.normal += weightedNormal;
b.normal += weightedNormal;
c.normal += weightedNormal;
}
// Normalise all normal vectors
for (Vertices::iterator j = _vertices.begin(); j != _vertices.end(); ++j)
{
j->normal = Normal3f(j->normal.getNormalised());
}
}
