private static void MeshesToFile(MeshFilter[] mf, string folder, string filename, WorldtoLocalParam param = null)
{
Dictionary <string, ObjMaterial> materialList = PrepareFileWrite();
using (StreamWriter sw = new StreamWriter(folder + "/" + filename + ".obj"))
{
sw.Write("mtllib ./" + filename + ".mtl\n");
for (int i = mf.Length - 1; i >= 0; i--)
{
sw.Write(MeshToString(mf[i], materialList, param));
}
}
MaterialsToFile(materialList, folder, filename);
}
private static string MeshToString(MeshFilter mf, Dictionary <string, ObjMaterial> materialList, WorldtoLocalParam param = null)
{
Mesh m = mf.sharedMesh;
Material[] mats = mf.GetComponent <Renderer>().sharedMaterials;
StringBuilder sb = new StringBuilder();
sb.Append("g ").Append(mf.name).Append("\n");
foreach (Vector3 lv in m.vertices)
{
Vector3 vec = lv;
//通过参数，可以还原原流星里的任意的 模型。
//if (param != null)
//{
// vec = vec + param.vec;
// vec = param.rotation * vec;
//}
//Vector3 wv = mf.transform.TransformPoint(lv);
Vector3 wv = vec;
//This is sort of ugly - inverting x-component since we're in
//a different coordinate system than "everyone" is "used to".
sb.Append(string.Format("v {0} {1} {2}\n", -wv.x, wv.y, wv.z));
}
sb.Append("\n");
foreach (Vector3 lv in m.normals)
{
Vector3 wv = mf.transform.TransformDirection(lv);
//Vector3 wv = lv;
sb.Append(string.Format("vn {0} {1} {2}\n", -wv.x, wv.y, wv.z));
}
sb.Append("\n");
foreach (Vector3 v in m.uv)
{
sb.Append(string.Format("vt {0} {1}\n", v.x, v.y));
}
for (int material = 0; material < m.subMeshCount; material++)
{
sb.Append("\n");
//See if this material is already in the materiallist.
try
{
if (material >= mats.Length)
{
continue;
}
if (mats[material] == null)
{
continue;
}
ObjMaterial objMaterial = new ObjMaterial();
if (mats[material].mainTexture)
{
//objMaterial.textureName = AssetDatabase.GetAssetPath(mats[material].mainTexture);
}
else
{
objMaterial.textureName = null;
}
string[] s = null;
string ss = null;
if (!string.IsNullOrEmpty(objMaterial.textureName))
{
s = objMaterial.textureName.Split(new char[] { '/' }, System.StringSplitOptions.RemoveEmptyEntries);
if (s != null && s.Length != 0)
{
ss = s[s.Length - 1];
}
}
objMaterial.name = mats[material].name + "_" + ss;
if (!materialList.ContainsKey(objMaterial.name))
{
materialList.Add(objMaterial.name, objMaterial);
}
sb.Append("usemtl ").Append(objMaterial.name).Append("\n");
sb.Append("usemap ").Append(objMaterial.name).Append("\n");
}
catch (ArgumentException)
{
//Already in the dictionary
}
int[] triangles = m.GetTriangles(material);
for (int i = 0; i < triangles.Length; i += 3)
{
//Because we inverted the x-component, we also needed to alter the triangle winding.
sb.Append(string.Format("f {1}/{1}/{1} {0}/{0}/{0} {2}/{2}/{2}\n",
triangles[i] + 1 + vertexOffset, triangles[i + 1] + 1 + normalOffset, triangles[i + 2] + 1 + uvOffset));
}
}
vertexOffset += m.vertices.Length;
normalOffset += m.normals.Length;
uvOffset += m.uv.Length;
return(sb.ToString());
}
