public static string GenerateObjFile(IEnumerable <VertexInfo[]> faces, string objectName = null, AutoNormal autoNormal = AutoNormal.None)
{
var facesProcessed = faces;
if (autoNormal != AutoNormal.None)
{
facesProcessed = faces.Select(face => face.Select(p => new VertexInfo(p.Location, p.Normal ?? (autoNormal == AutoNormal.Flat && face.Length >= 3 ? (face[2].Location - face[1].Location) * (face[0].Location - face[1].Location) : (Pt?)null), p.Texture)).ToArray());
}
var facesArr = facesProcessed.ToArray();
var vertices = facesArr.SelectMany(f => f).Select(f => f.Location).Distinct().ToArray();
var verticesLookup = vertices.Select((v, i) => Ut.KeyValuePair(v, i + 1)).ToDictionary();
var normals = facesArr.SelectMany(f => f).Where(f => f.Normal != null).Select(f => f.Normal.Value).Distinct().ToArray();
var normalsLookup = normals.Select((n, i) => Ut.KeyValuePair(n, i + 1)).ToDictionary();
var textures = facesArr.SelectMany(f => f).Where(f => f.Texture != null).Select(f => f.Texture.Value).Distinct().ToArray();
var s = new StringBuilder();
if (objectName != null)
{
s.AppendLine($"o {objectName}");
}
foreach (var v in vertices)
{
s.AppendLine($"v {v.X:R} {v.Y:R} {v.Z:R}");
}
foreach (var n in normals)
{
s.AppendLine($"vn {n.X:R} {n.Y:R} {n.Z:R}");
}
foreach (var t in textures)
{
s.AppendLine($"vt {t.X:R} {t.Y:R}");
}
if (objectName != null)
{
s.AppendLine($"g {objectName}");
}
foreach (var f in facesArr)
{
s.AppendLine($@"f {f.Select(vi =>
verticesLookup[vi.Location].Apply(v =>
vi.Texture.NullOr(t => textures.IndexOf(t) + 1).Apply(t =>
vi.Normal.NullOr(n => normalsLookup[n]).Apply(n =>
n == null ? t == null ? v.ToString() : $"{v}/{t}" : $"{v}/{t}/{n}")))).JoinString(" ")}");
}
public static string GenerateObjFile(IEnumerable <Pt[]> faces, string objectName = null, AutoNormal autoNormal = AutoNormal.None)
{
return(GenerateObjFile(faces.Select(face => face.Select(p => new VertexInfo(p, null)).ToArray()).ToArray(), objectName));
}
