/// <summary>
/// This will find if the vertex is already contained and return its index, otherwise it adds it as new
/// </summary>
public OBJFaceVertex AddOrGet(Vertex vertex)
{
OBJFaceVertex face = new OBJFaceVertex();
// Position
for (int i = 0; i < positions.Count; i++)
{
if (positions[i] == vertex.Position)
{
face.PositionIndex = i + 1;
}
}
if (face.PositionIndex == 0)
{
positions.Add(vertex.Position);
face.PositionIndex = positions.Count;
}
// UV
for (int i = 0; i < uvs.Count; i++)
{
if (uvs[i] == vertex.UV)
{
face.UVIndex = i + 1;
}
}
if (face.UVIndex == 0)
{
uvs.Add(vertex.UV);
face.UVIndex = uvs.Count;
}
// Normal
for (int i = 0; i < normals.Count; i++)
{
if (normals[i] == vertex.Normal)
{
face.NormalIndex = i + 1;
}
}
if (face.NormalIndex == 0)
{
normals.Add(vertex.Normal);
face.NormalIndex = normals.Count;
}
return(face);
}
/// <summary>
/// This will find if the vertex is already contained and return its index, otherwise it adds it as new
/// </summary>
public OBJFaceVertex AddOrGet(Vertex vertex)
{
OBJFaceVertex face = new OBJFaceVertex();
// Position
for (int i = 0; i < positions.Count; i++)
{
if (positions[i] == vertex.Position)
{
face.PositionIndex = i+1;
}
}
if(face.PositionIndex == 0)
{
positions.Add(vertex.Position);
face.PositionIndex = positions.Count;
}
// UV
for (int i = 0; i < uvs.Count; i++)
{
if (uvs[i] == vertex.UV)
{
face.UVIndex = i+1;
}
}
if(face.UVIndex == 0)
{
uvs.Add(vertex.UV);
face.UVIndex = uvs.Count;
}
// Normal
for (int i = 0; i < normals.Count; i++)
{
if (normals[i] == vertex.Normal)
{
face.NormalIndex = i+1;
}
}
if(face.NormalIndex == 0)
{
normals.Add(vertex.Normal);
face.NormalIndex = normals.Count;
}
return face;
}
public static string ExportToString(Transform transform, List <Polygon> polygons, Material defaultMaterial)
{
// If a transform is provided, convert the world positions and normals to local to the transform
if (transform != null)
{
for (int polygonIndex = 0; polygonIndex < polygons.Count; polygonIndex++)
{
Polygon polygon = polygons[polygonIndex];
for (int vertexIndex = 0; vertexIndex < polygon.Vertices.Length; vertexIndex++)
{
Vertex vertex = polygon.Vertices[vertexIndex];
vertex.Position = transform.InverseTransformPoint(vertex.Position);
vertex.Normal = transform.InverseTransformDirection(vertex.Normal);
}
}
}
// Create polygon subsets for each material
Dictionary <Material, List <Polygon> > polygonMaterialTable = new Dictionary <Material, List <Polygon> >();
// Iterate through every polygon adding it to the appropiate material list
foreach (Polygon polygon in polygons)
{
if (polygon.UserExcludeFromFinal)
{
continue;
}
Material material = polygon.Material;
if (material == null)
{
material = defaultMaterial;
}
if (!polygonMaterialTable.ContainsKey(material))
{
polygonMaterialTable.Add(material, new List <Polygon>());
}
polygonMaterialTable[material].Add(polygon);
}
// Use a string builder as this should allow faster concatenation
StringBuilder stringBuilder = new StringBuilder();
OBJVertexList vertexList = new OBJVertexList();
int positionIndexOffset = 0;
int uvIndexOffset = 0;
int normalIndexOffset = 0;
int meshIndex = 1;
// Create a separate mesh for polygons of each material so that we batch by material
foreach (KeyValuePair <Material, List <Polygon> > polygonMaterialGroup in polygonMaterialTable)
{
List <List <OBJFaceVertex> > faces = new List <List <OBJFaceVertex> >(polygonMaterialGroup.Value.Count);
// Iterate through every polygon and triangulate
foreach (Polygon polygon in polygonMaterialGroup.Value)
{
List <OBJFaceVertex> faceVertices = new List <OBJFaceVertex>(polygon.Vertices.Length);
for (int i = 0; i < polygon.Vertices.Length; i++)
{
OBJFaceVertex faceVertex = vertexList.AddOrGet(polygon.Vertices[i]);
faceVertices.Add(faceVertex);
}
faces.Add(faceVertices);
}
List <Vector3> positions = vertexList.Positions;
List <Vector2> uvs = vertexList.UVs;
List <Vector3> normals = vertexList.Normals;
// Start a new group for the mesh
stringBuilder.AppendLine("g Mesh" + meshIndex);
// Write all the positions
stringBuilder.AppendLine("# Vertex Positions: " + (positions.Count - positionIndexOffset));
for (int i = positionIndexOffset; i < positions.Count; i++)
{
stringBuilder.AppendLine("v " + WriteVector3(positions[i]));
}
// Write all the texture coordinates (UVs)
stringBuilder.AppendLine("# Vertex UVs: " + (uvs.Count - uvIndexOffset));
for (int i = uvIndexOffset; i < uvs.Count; i++)
{
stringBuilder.AppendLine("vt " + WriteVector2(uvs[i]));
}
// Write all the normals
stringBuilder.AppendLine("# Vertex Normals: " + (normals.Count - normalIndexOffset));
for (int i = normalIndexOffset; i < normals.Count; i++)
{
stringBuilder.AppendLine("vn " + WriteVector3(normals[i]));
}
// Write all the faces
stringBuilder.AppendLine("# Faces: " + faces.Count);
for (int i = 0; i < faces.Count; i++)
{
stringBuilder.Append("f ");
for (int j = faces[i].Count - 1; j >= 0; j--)
{
stringBuilder.Append((faces[i][j].PositionIndex) + "/" + (faces[i][j].UVIndex) + "/" + (faces[i][j].NormalIndex) + " ");
}
stringBuilder.AppendLine();
}
// Add some padding between this and the next mesh
stringBuilder.AppendLine();
stringBuilder.AppendLine();
meshIndex++;
// Update the offsets so that the next pass only writes new vertex information
positionIndexOffset = positions.Count;
uvIndexOffset = uvs.Count;
normalIndexOffset = normals.Count;
}
return(stringBuilder.ToString());
}
