/// <summary>
/// Calculate the tangents to the surface of a mesh constructed by an array of vertices
/// </summary>
/// <param name="verts">The array of vertices that make up the mesh with valid UV properties</param>
public static void CalculateTangents(ref Vertex[] verts)
{
for (int i = 0; i < verts.Length; i += 3)
{
Vector3 v0 = verts[i].Position;
Vector3 v1 = verts[i + 1].Position;
Vector3 v2 = verts[i + 2].Position;
Vector3 edge1 = v1 - v0;
Vector3 edge2 = v2 - v0;
Vector2 uv0 = verts[i].UV;
Vector2 uv1 = verts[i + 1].UV;
Vector2 uv2 = verts[i + 2].UV;
float DeltaU1 = uv1.X - uv0.X;
float DeltaV1 = uv1.Y - uv0.Y;
float DeltaU2 = uv2.X - uv0.X;
float DeltaV2 = uv2.Y - uv0.Y;
float f = 1.0f / (DeltaU1 * DeltaV2 - DeltaU2 * DeltaV1);
Vector3 Tangent;
Tangent = new Vector3()
{
X = f * (DeltaV2 * edge1.X - DeltaV1 * edge2.X),
Y = f * (DeltaV2 * edge1.Y - DeltaV1 * edge2.Y),
Z = f * (DeltaV2 * edge1.Z - DeltaV1 * edge2.Z),
};
Tangent.Normalize();
verts[i].Tangent = Tangent;
verts[i + 1].Tangent = Tangent;
verts[i + 2].Tangent = Tangent;
}
}
/// <summary>
/// Utility function to construct an array of three vertices
/// </summary>
/// <param name="first">The first vertex</param>
/// <param name="second">The second vertex</param>
/// <param name="third">The third vertex</param>
/// <returns>Array of vertices that form a tri</returns>
public static Vertex[] AddTri(Vertex first, Vertex second, Vertex third)
{
Vertex[] verts = new Vertex[3];
verts[0] = first;
verts[1] = second;
verts[2] = third;
return verts;
}
private int[] GenerateElements(Vertex[] verts)
{
int[] elements = new int[verts.Length];
for (int i = 0; i < elements.Length; i++)
{
elements[i] = i;
}
return elements;
}
/// <summary>
/// Utility function to construct a quad from four vertices
/// </summary>
/// <param name="bottomleft">Bottom left vertex</param>
/// <param name="topleft">Top left vertex</param>
/// <param name="topright">Top right vertex</param>
/// <param name="bottomright">Bottom right vertex</param>
/// <returns>Array of vertices that form a quad</returns>
public static Vertex[] AddQuad(Vertex bottomleft, Vertex topleft, Vertex topright, Vertex bottomright)
{
Vertex[] verts = new Vertex[6];
verts[5] = bottomleft;
verts[4] = bottomright;
verts[3] = topright;
verts[2] = topright;
verts[1] = topleft;
verts[0] = bottomleft;
return verts;
}
public static Mesh.BoundingBox CalculateBoundingBox(Vertex[] vertices, Vector3 scale)
{
Mesh.BoundingBox bbox = new Mesh.BoundingBox(Vector3.One * float.MaxValue, Vector3.One * float.MinValue);
for (int i = 0; i < vertices.Length; i++)
{
Vector3 vertex = vertices[i].Position.Multiply(scale);
//Update the size of the bounding box
bbox.Negative = bbox.NegativeSet ? SmallestVec(bbox.Negative, vertex) : vertex;
bbox.Positive = bbox.PositiveSet ? BiggestVec(bbox.Positive, vertex) : vertex;
}
return bbox;
}
public static Mesh MeshFromData(Vertex[] lsVerts, int[] lsElements, Mesh.BoundingBox boundingBox, string Material)
{
//Try to load the material
Material mat = Resource.GetMaterial(Material);
//Create the model
Mesh m = new Mesh(lsVerts, lsElements);
m.mat = mat;
return m;
}
public static MeshGroup LoadOBJMulti(string filename)
{
List<Mesh> meshList = new List<Mesh>();
filename = Resource.ModelDir + filename;
string material = "";
string[] file = null;
try
{
file = System.IO.File.ReadAllLines(filename);
}
catch (System.IO.FileNotFoundException ex)
{
Console.WriteLine("Failed to load level file: " + ex.Message);
}
if (file == null || file.Length == 0)
{
Console.WriteLine("Failed to load level file: An unknown error occurred!");
return null;
}
//scan the file and look for the number of stuffs
List<Vector3> verts_UNSORTED = new List<Vector3>();
List<Vector3> normals_UNSORTED = new List<Vector3>();
List<Vector2> uv_UNSORTED = new List<Vector2>();
List<Vertex> vertices = new List<Vertex>();
List<int> elements = new List<int>();
for (int i = 0; i < file.Length; i++)
{
string curline = file[i];
string seg1 = curline.Split(' ')[0];
switch (seg1)
{
case "v":
string[] vert = curline.Split(' ');
if (vert[1].Length == 0 && vert.Length > 4)
{
verts_UNSORTED.Add(new Vector3(ParseFloatSafe(vert[2]), ParseFloatSafe(vert[3]), ParseFloatSafe(vert[4])));
}
else
{
verts_UNSORTED.Add(new Vector3(ParseFloatSafe(vert[1]), ParseFloatSafe(vert[2]), ParseFloatSafe(vert[3])));
}
break;
case "vn":
string[] norms = curline.Split(' ');
if (norms[1].Length == 0 && norms.Length > 4)
{
normals_UNSORTED.Add(new Vector3(ParseFloatSafe(norms[2]), ParseFloatSafe(norms[3]), ParseFloatSafe(norms[4])));
}
else
{
normals_UNSORTED.Add(new Vector3(ParseFloatSafe(norms[1]), ParseFloatSafe(norms[2]), ParseFloatSafe(norms[3])));
}
break;
case "vt":
string[] coords = curline.Split(' ');
if (coords[1].Length == 0 && coords.Length > 3)
{
uv_UNSORTED.Add(new Vector2(ParseFloatSafe(coords[2]), -ParseFloatSafe(coords[3])));
}
else
{
uv_UNSORTED.Add(new Vector2(ParseFloatSafe(coords[1]), -ParseFloatSafe(coords[2])));
}
break;
case "f":
string[] element = curline.Split(' ');
for (int n = 1; n < 4; n++)
{
string[] group = element[n].Split('/');
Vertex vertex = new Vertex();
vertex.Color = (Vector3h)Vector3.One;
if (group.Length > 0 && group[0].Length > 0)
{
int vertNum = int.Parse(group[0]);
if (vertNum < verts_UNSORTED.Count + 1)
{
vertex.Position = verts_UNSORTED[vertNum - 1];
elements.Add(elements.Count);
}
}
if (group.Length > 1 && group[1].Length > 0)
{
int uvNum = int.Parse(group[1]);
if (uvNum < uv_UNSORTED.Count + 1)
{
vertex.UV = uv_UNSORTED[uvNum - 1];
}
}
if (group.Length > 2 && group[2].Length > 0)
{
int normNum = int.Parse(group[2]);
if (normNum < normals_UNSORTED.Count + 1)
{
vertex.Normal = normals_UNSORTED[normNum - 1];
}
}
vertices.Add(vertex);
}
break;
//Specify what material this object should use
case "usemtl":
string[] mtlline = curline.Split(' ');
if (mtlline.Length > 0)
{
material = mtlline[1];
}
break;
case "o":
case "g":
//If there is info, compile it into a model
if (vertices.Count > 0)
{
meshList.Add(MeshFromRawData(vertices, elements, material));
}
// Reset everything for this new mesh
vertices = new List<Vertex>();
elements = new List<int>();
break;
case "#":
//Console.WriteLine("Comment: {0}", curline );
break;
default:
break;
}
}
//If there is info, compile it into a model
if (vertices.Count > 0)
{
meshList.Add(MeshFromRawData(vertices, elements, material));
}
return new MeshGroup(meshList);
}
public static void LoadOBJFromString(string objString, out Vertex[] lsVerts, out int[] lsElements, out Mesh.BoundingBox boundingBox)
{
lsVerts = null;
lsElements = null;
boundingBox = new Mesh.BoundingBox();
string[] file = objString.Split(new string[] { "\r\n", "\n" }, StringSplitOptions.None);
//scan the file and look for the number of stuffs
List<Vector3> verts_UNSORTED = new List<Vector3>();
List<Vector3> normals_UNSORTED = new List<Vector3>();
List<Vector2> uv_UNSORTED = new List<Vector2>();
List<Vector3> tangents = new List<Vector3>();
List<Vertex> vertices = new List<Vertex>();
List<int> elements = new List<int>();
for (int i = 0; i < file.Length; i++)
{
string curline = file[i];
string seg1 = curline.Split(' ')[0];
switch (seg1)
{
case "v":
string[] vert = curline.Split(' ');
if (vert[1].Length == 0 && vert.Length > 4)
{
verts_UNSORTED.Add(new Vector3(ParseFloatSafe(vert[2]), ParseFloatSafe(vert[3]), ParseFloatSafe(vert[4])));
}
else
{
verts_UNSORTED.Add(new Vector3(ParseFloatSafe(vert[1]), ParseFloatSafe(vert[2]), ParseFloatSafe(vert[3])));
}
break;
case "vn":
string[] norms = curline.Split(' ');
if (norms[1].Length == 0 && norms.Length > 4)
{
normals_UNSORTED.Add(new Vector3(ParseFloatSafe(norms[2]), ParseFloatSafe(norms[3]), ParseFloatSafe(norms[4])));
}
else
{
normals_UNSORTED.Add(new Vector3(ParseFloatSafe(norms[1]), ParseFloatSafe(norms[2]), ParseFloatSafe(norms[3])));
}
break;
case "vt":
string[] coords = curline.Split(' ');
if (coords[1].Length == 0 && coords.Length > 3)
{
uv_UNSORTED.Add(new Vector2(ParseFloatSafe(coords[2]), -ParseFloatSafe(coords[3])));
}
else
{
uv_UNSORTED.Add(new Vector2(ParseFloatSafe(coords[1]), -ParseFloatSafe(coords[2])));
}
break;
case "f":
string[] element = curline.Split(' ');
for (int n = 1; n < 4; n++)
{
string[] group = element[n].Split('/');
Vertex newVert = new Vertex();
newVert.Color = (Vector3h)Vector3.One;
if (group.Length > 0 && group[0].Length > 0)
{
int vertNum = int.Parse(group[0]);
if (vertNum < verts_UNSORTED.Count + 1)
{
newVert.Position = verts_UNSORTED[vertNum - 1];
elements.Add(elements.Count);
}
}
if (group.Length > 1 && group[1].Length > 0)
{
int uvNum = int.Parse(group[1]);
if (uvNum < uv_UNSORTED.Count + 1)
{
newVert.UV = uv_UNSORTED[uvNum - 1];
}
}
if (group.Length > 2 && group[2].Length > 0)
{
int normNum = int.Parse(group[2]);
if (normNum < normals_UNSORTED.Count + 1)
{
newVert.Normal = normals_UNSORTED[normNum - 1];
}
}
vertices.Add(newVert);
}
break;
case "#":
//Console.WriteLine("Comment: {0}", curline );
break;
default:
break;
}
}
//Slap them into normal arrays, we won't be changing it much now
lsElements = elements.ToArray();
lsVerts = vertices.ToArray();
//Calculate the tangents
CalculateTangents(ref lsVerts);
//Calculate the bounding box
boundingBox = CalculateBoundingBox(lsVerts, Vector3.One);
}
public static void LoadOBJ(string filename, out Vertex[] lsVerts, out int[] lsElements, out Mesh.BoundingBox boundingBox)
{
filename = Resource.ModelDir + filename;
string file = null;
lsVerts = null;
lsElements = null;
boundingBox = new Mesh.BoundingBox();
try
{
file = System.IO.File.ReadAllText(filename);
}
catch (Exception ex)
{
Utilities.Print("Failed to load model '{0}'. {1}", Utilities.PrintCode.ERROR, filename, ex.Message);
}
if (file == null || file.Length == 0)
{
Utilities.Print("Failed to load model '{0}'. File is empty!", Utilities.PrintCode.ERROR, filename);
return;
}
LoadOBJFromString(file, out lsVerts, out lsElements, out boundingBox);
}
