/// <summary>
/// Load an OBJ file from a stream. No materials will be loaded, and will instead be supplemented by a blank white material.
/// </summary>
/// <param name="input">Input OBJ stream</param>
/// <returns>Returns a GameObject represeting the OBJ file, with each imported object as a child.</returns>
public GameObject Load(Stream input)
{
var inputReader = new StreamReader(input);
var reader = new StringReader(inputReader.ReadToEnd());
Dictionary <string, OBJObjectBuilder> builderDict = new Dictionary <string, OBJObjectBuilder>();
OBJObjectBuilder currentBuilder = null;
string currentMaterial = "default";
//lists for face data
//prevents excess GC
List <int> vertexIndices = new List <int>();
List <int> normalIndices = new List <int>();
List <int> uvIndices = new List <int>();
//helper func
Action <string> setCurrentObjectFunc = (string objectName) =>
{
if (!builderDict.TryGetValue(objectName, out currentBuilder))
{
currentBuilder = new OBJObjectBuilder(objectName, this);
builderDict[objectName] = currentBuilder;
}
};
//create default object
setCurrentObjectFunc.Invoke("default");
//do the reading
for (string line = reader.ReadLine(); line != null; line = reader.ReadLine())
{
if (StringExtension.IsNullOrWhiteSpace(line))
{
continue;
}
string processedLine = line.Clean();
string[] splitLine = processedLine.Split(' ');
//comment or blank
if (processedLine[0] == '#' || splitLine.Length < 2)
{
continue;
}
//load material library
if (splitLine[0] == "mtllib" && Materials == null)
{
string mtlLibPath = processedLine.Substring(7);
LoadMaterialLibrary(mtlLibPath);
}
//vtx
if (splitLine[0] == "v")
{
Vertices.Add(OBJLoaderHelper.VectorFromStrArray(splitLine));
continue;
}
//normal
if (splitLine[0] == "vn")
{
Normals.Add(OBJLoaderHelper.VectorFromStrArray(splitLine));
continue;
}
//uv
if (splitLine[0] == "vt")
{
UVs.Add(OBJLoaderHelper.VectorFromStrArray(splitLine));
continue;
}
//new material
if (splitLine[0] == "usemtl")
{
string materialName = processedLine.Substring(7);
currentMaterial = materialName;
if (SplitMode == SplitMode.Material)
{
setCurrentObjectFunc.Invoke(materialName);
}
continue;
}
//new object
if ((splitLine[0] == "o" || splitLine[0] == "g") && SplitMode == SplitMode.Object)
{
string objectName = processedLine.Substring(2);
setCurrentObjectFunc.Invoke(objectName);
continue;
}
//face data (the fun part)
if (splitLine[0] == "f")
{
//loop through indices
for (int i = 1; i < splitLine.Length; i++)
{
string faceLoop = splitLine[i];
int vertexIndex = int.MinValue;
int normalIndex = int.MinValue;
int uvIndex = int.MinValue;
//parse face loop
if (faceLoop.Contains("//"))
{
//vertex and normal
string[] slashSplits = faceLoop.Split('/');
vertexIndex = OBJLoaderHelper.FastIntParse(slashSplits[0]);
normalIndex = OBJLoaderHelper.FastIntParse(slashSplits[2]);
}
else if (faceLoop.Contains("/"))
{
//get slash splits
string[] slashSplits = faceLoop.Split('/');
if (slashSplits.Length > 2)
{
//vertex, uv, and normal
vertexIndex = OBJLoaderHelper.FastIntParse(slashSplits[0]);
uvIndex = OBJLoaderHelper.FastIntParse(slashSplits[1]);
normalIndex = OBJLoaderHelper.FastIntParse(slashSplits[2]);
}
else
{
//vertex, and uv
vertexIndex = OBJLoaderHelper.FastIntParse(slashSplits[0]);
uvIndex = OBJLoaderHelper.FastIntParse(slashSplits[1]);
}
}
else
{
//just vertex index
vertexIndex = OBJLoaderHelper.FastIntParse(faceLoop);
}
//"postprocess" indices
if (vertexIndex > int.MinValue)
{
if (vertexIndex < 0)
{
vertexIndex = Vertices.Count - vertexIndex;
}
vertexIndex--;
}
if (normalIndex > int.MinValue)
{
if (normalIndex < 0)
{
normalIndex = Normals.Count - normalIndex;
}
normalIndex--;
}
if (uvIndex > int.MinValue)
{
if (uvIndex < 0)
{
uvIndex = UVs.Count - uvIndex;
}
uvIndex--;
}
//set array values
vertexIndices.Add(vertexIndex);
normalIndices.Add(normalIndex);
uvIndices.Add(uvIndex);
}
//push to builder
currentBuilder.PushFace(currentMaterial, vertexIndices, normalIndices, uvIndices);
//clear lists
vertexIndices.Clear();
normalIndices.Clear();
uvIndices.Clear();
}
}
//finally, put it all together
GameObject obj = new GameObject(_objInfo != null ? Path.GetFileNameWithoutExtension(_objInfo.Name) : "WavefrontObject");
obj.transform.localScale = new Vector3(-1f, 1f, 1f);
foreach (var builder in builderDict)
{
//empty object
if (builder.Value.PushedFaceCount == 0)
{
continue;
}
var builtObj = builder.Value.Build();
builtObj.transform.SetParent(obj.transform, false);
}
return(obj);
}
public GameObject Build()
{
var go = new GameObject(_name);
//add meshrenderer
var mr = go.AddComponent <MeshRenderer>();
int submesh = 0;
//locate the material for each submesh
Material[] materialArray = new Material[_materialIndices.Count];
foreach (var kvp in _materialIndices)
{
Material material = null;
if (_loader.Materials == null)
{
material = OBJLoaderHelper.CreateNullMaterial();
material.name = kvp.Key;
}
else
{
if (!_loader.Materials.TryGetValue(kvp.Key, out material))
{
material = OBJLoaderHelper.CreateNullMaterial();
material.name = kvp.Key;
_loader.Materials[kvp.Key] = material;
}
}
materialArray[submesh] = material;
submesh++;
}
mr.sharedMaterials = materialArray;
//add meshfilter
var mf = go.AddComponent <MeshFilter>();
submesh = 0;
var msh = new Mesh()
{
name = _name,
indexFormat = (_vertices.Count > 65535) ? UnityEngine.Rendering.IndexFormat.UInt32 : UnityEngine.Rendering.IndexFormat.UInt16,
subMeshCount = _materialIndices.Count
};
//set vertex data
msh.SetVertices(_vertices);
msh.SetNormals(_normals);
msh.SetUVs(0, _uvs);
//set faces
foreach (var kvp in _materialIndices)
{
msh.SetTriangles(kvp.Value, submesh);
submesh++;
}
//recalculations
if (recalculateNormals)
{
msh.RecalculateNormals();
}
//msh.RecalculateTangents();
//msh.RecalculateBounds();
mf.sharedMesh = msh;
return(go);
}
