/// <summary>
/// Creates a Mesh object based on a Wavefront OBJ file.
/// </summary>
/// <param name="path">Path to the file</param>
/// <returns></returns>
public static Mesh FromOBJ(string path, bool center = false)
{
Mesh NewMesh = new Mesh();
// Parse vertices
using (TextReader Reader = new StreamReader(File.OpenRead(path)))
{
string Line = Reader.ReadLine();
while (Line != null)
{
string[] Parts = Line.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
if (Parts.Length > 0 && Parts[0] == "v")
NewMesh.Vertices.Add(new Vertex(new Vector3(float.Parse(Parts[1]), float.Parse(Parts[2]), float.Parse(Parts[3])), new Vector3(1, 0, 0)));
Line = Reader.ReadLine();
}
}
if (center)
{
Vector3 Center = Vector3.Zero;
Vector3 CenterVolume = Vector3.Zero;
foreach (var v in NewMesh.Vertices)
{
Center += v.Position;
CenterVolume += v.VolumePosition;
}
Center /= NewMesh.Vertices.Count;
CenterVolume /= NewMesh.Vertices.Count;
foreach (var v in NewMesh.Vertices)
{
v.Position -= Center;
v.VolumePosition -= CenterVolume;
}
}
// Parse faces
using (TextReader Reader = new StreamReader(File.OpenRead(path)))
{
string Line = Reader.ReadLine();
while (Line != null)
{
string[] Parts = Line.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
if (Parts.Length > 0 && Parts[0] == "f")
{
string[] FaceParts0 = Parts[1].Split(new[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
string[] FaceParts1 = Parts[2].Split(new[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
string[] FaceParts2 = Parts[3].Split(new[] { '/' }, StringSplitOptions.RemoveEmptyEntries);
NewMesh.Triangles.Add(new Triangle(NewMesh.Triangles.Count,
NewMesh.Vertices[int.Parse(FaceParts0[0]) - 1],
NewMesh.Vertices[int.Parse(FaceParts1[0]) - 1],
NewMesh.Vertices[int.Parse(FaceParts2[0]) - 1]));
}
Line = Reader.ReadLine();
}
}
// Amira likes to put unused vertices into the OBJ
NewMesh.Vertices.RemoveAll(v => v.Triangles.Count == 0);
NewMesh.UpdateGraph();
NewMesh.UpdateVertexIDs();
return NewMesh;
}
/// <summary>
/// Implementation of Marching Cubes based on http://paulbourke.net/geometry/polygonise/
/// </summary>
/// <param name="volume">Volume intensity values</param>
/// <param name="dims">Volume dimensions</param>
/// <param name="angpix">Angstrom per pixel</param>
/// <param name="threshold">Isosurface threshold</param>
/// <returns></returns>
public static Mesh FromVolume(float[] volume, int3 dims, float angpix, float threshold)
{
Triangle[][] CellTriangles = new Triangle[volume.Length][];
unsafe
{
fixed (float* volumePtr = volume)
for (int z = 0; z < dims.Z - 1; z++)
{
float zz = (z - dims.Z / 2) * angpix;
for (int y = 0; y < dims.Y - 1; y++)
{
float yy = (y - dims.Y / 2) * angpix;
for (int x = 0; x < dims.X - 1; x++)
{
float xx = (x - dims.X / 2) * angpix;
Vector3[] p = new Vector3[8];
float[] val = new float[8];
p[0] = new Vector3(xx, yy, zz);
p[1] = new Vector3(xx + angpix, yy, zz);
p[2] = new Vector3(xx + angpix, yy + angpix, zz);
p[3] = new Vector3(xx, yy + angpix, zz);
p[4] = new Vector3(xx, yy, zz + angpix);
p[5] = new Vector3(xx + angpix, yy, zz + angpix);
p[6] = new Vector3(xx + angpix, yy + angpix, zz + angpix);
p[7] = new Vector3(xx, yy + angpix, zz + angpix);
val[0] = volumePtr[((z + 0) * dims.Y + (y + 0)) * dims.X + (x + 0)];
val[1] = volumePtr[((z + 0) * dims.Y + (y + 0)) * dims.X + (x + 1)];
val[2] = volumePtr[((z + 0) * dims.Y + (y + 1)) * dims.X + (x + 1)];
val[3] = volumePtr[((z + 0) * dims.Y + (y + 1)) * dims.X + (x + 0)];
val[4] = volumePtr[((z + 1) * dims.Y + (y + 0)) * dims.X + (x + 0)];
val[5] = volumePtr[((z + 1) * dims.Y + (y + 0)) * dims.X + (x + 1)];
val[6] = volumePtr[((z + 1) * dims.Y + (y + 1)) * dims.X + (x + 1)];
val[7] = volumePtr[((z + 1) * dims.Y + (y + 1)) * dims.X + (x + 0)];
CellTriangles[(z * dims.Y + y) * dims.X + x] = Polygonize(p, val, threshold);
}
}
}
}
Mesh NewMesh = new Mesh();
for (int i = 0; i < CellTriangles.Length; i++)
{
if (CellTriangles[i] == null)
continue;
foreach (var tri in CellTriangles[i])
{
NewMesh.Vertices.Add(tri.V0);
NewMesh.Vertices.Add(tri.V1);
NewMesh.Vertices.Add(tri.V2);
tri.ID = NewMesh.Triangles.Count;
NewMesh.Triangles.Add(tri);
}
}
NewMesh.UpdateGraph();
NewMesh.UpdateVertexIDs();
return NewMesh;
}
public SurfacePatch(Membrane membrane, string name, Color color, IEnumerable<Triangle> triangles)
{
Membrane = membrane;
Name = name;
Color = color;
Dictionary<Vertex, Vertex> VertexToTransformed = new Dictionary<Vertex, Vertex>();
List<Triangle> NewTriangles = new List<Triangle>(triangles.Count());
foreach (var t in triangles)
{
foreach (var v in t.Vertices)
if (!VertexToTransformed.ContainsKey(v))
VertexToTransformed.Add(v, new Vertex(v.VolumePosition, v.VolumeNormal));
Triangle NewTriangle = new Triangle(t.ID, VertexToTransformed[t.V0], VertexToTransformed[t.V1], VertexToTransformed[t.V2]);
NewTriangles.Add(NewTriangle);
OriginalToTransformed.Add(t, NewTriangle);
TransformedToOriginal.Add(NewTriangle, t);
}
SurfaceMesh = new Mesh();
SurfaceMesh.Vertices.AddRange(VertexToTransformed.Values);
SurfaceMesh.Triangles.AddRange(OriginalToTransformed.Values);
SurfaceMesh.UpdateGraph();
SurfaceMesh.UpdateVertexIDs();
TurnUpsideUp();
// Don't update buffers because there is no OpenGL context yet.
UpdateStats();
UpdatePlanarizationStats();
Membrane.DisplayedPatches.CollectionChanged += MembraneDisplayedPatches_CollectionChanged;
Membrane.PointGroups.CollectionChanged += MembranePointGroups_CollectionChanged;
MembranePointGroups_CollectionChanged(null, null);
}
