internal static void CheckMeshFaces(Mesh mesh, ErrorLogger logger) {
for (int f = 0; f < mesh.Faces.Length; f++) {
if (mesh.Faces[f].Vertices.Length <= 2) {
logger.Add("Face " + (f + 1).ToString() + " has less than 3 vertices.");
} else {
int ai = mesh.Faces[f].Vertices[0];
int bi = mesh.Faces[f].Vertices[1];
int ci = mesh.Faces[f].Vertices[2];
Vector3f a = mesh.Vertices[ai].Position;
Vector3f b = mesh.Vertices[bi].Position;
Vector3f c = mesh.Vertices[ci].Position;
Vector3f ab = b - a;
Vector3f ac = c - a;
Vector3f dx = Vector3f.Normalize(ab);
Vector3f dy = Vector3f.Normalize(Vector3f.Cross(Vector3f.Cross(ab, ac), ab));
Vector2f[] projection = new Vector2f[mesh.Faces[f].Vertices.Length];
for (int i = 0; i < mesh.Faces[f].Vertices.Length; i++) {
int v = mesh.Faces[f].Vertices[i];
float x = Vector3f.Dot(mesh.Vertices[v].Position - a, dx);
float y = Vector3f.Dot(mesh.Vertices[v].Position - a, dy);
projection[i] = new Vector2f(x, y);
}
int winding = Math.Sign(GetWinding(projection, 0));
for (int i = 1; i < mesh.Faces[f].Vertices.Length; i++) {
int value = Math.Sign(GetWinding(projection, i));
if (value != winding) {
logger.Add("Face " + (f + 1).ToString() + " has an incorrect winding. This usually indicates coinciding vertices, a concave or complex polygon, or a non-planar face. Line number: " + mesh.Faces[f].LineNumber.ToString());
break;
}
}
}
}
}
public abstract Object3D Add(Mesh mesh);