/// <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); }