/// <summary>
/// Recalculates a mesh's normals while retaining smoothed common vertices.
/// </summary>
/// <param name="mesh"></param>
internal static void RecalculateNormals(PolyMesh mesh)
{
//null checks
if (mesh == null)
{
return;
}
List <List <int> > smooth = GetSmoothSeamLookup(mesh);
mesh.RecalculateNormals();
if (smooth != null)
{
Vector3[] normals = mesh.normals;
foreach (List <int> l in smooth)
{
Vector3 n = PolyMath.Average(normals, l);
foreach (int i in l)
{
normals[i] = n;
}
}
mesh.normals = normals;
}
}
/// <summary>
/// Recalculates the normals of the Mesh from the triangles and vertices.
/// </summary>
internal void RecalculateNormals()
{
Vector3[] perTriangleNormal = new Vector3[vertexCount];
int[] perTriangleAvg = new int[vertexCount];
int[] tris = GetTriangles();
for (int i = 0; i < tris.Length; i += 3)
{
int a = tris[i], b = tris[i + 1], c = tris[i + 2];
Vector3 cross = PolyMath.Normal(vertices[a], vertices[b], vertices[c]);
perTriangleNormal[a].x += cross.x;
perTriangleNormal[b].x += cross.x;
perTriangleNormal[c].x += cross.x;
perTriangleNormal[a].y += cross.y;
perTriangleNormal[b].y += cross.y;
perTriangleNormal[c].y += cross.y;
perTriangleNormal[a].z += cross.z;
perTriangleNormal[b].z += cross.z;
perTriangleNormal[c].z += cross.z;
perTriangleAvg[a]++;
perTriangleAvg[b]++;
perTriangleAvg[c]++;
}
for (int i = 0; i < vertexCount; i++)
{
normals[i].x = perTriangleNormal[i].x * (float)perTriangleAvg[i];
normals[i].y = perTriangleNormal[i].y * (float)perTriangleAvg[i];
normals[i].z = perTriangleNormal[i].z * (float)perTriangleAvg[i];
normals[i].Normalize();
}
}
