/// <summary>
/// Gets the contour segments.
/// </summary>
/// <param name="mesh">
/// The mesh.
/// </param>
/// <param name="plane">
/// The plane origin.
/// </param>
/// <param name="normal">
/// The plane normal.
/// </param>
/// <returns>
/// The segments of the contour.
/// </returns>
public static IList <Point3D> GetContourSegments(this MeshGeometry3D mesh, Point3D plane, Vector3D normal)
{
var segments = new List <Point3D>();
var contourHelper = new ContourHelper(plane, normal, mesh);
for (int i = 0; i < mesh.TriangleIndices.Count; i += 3)
{
Point3D[] positions;
Vector3D[] normals;
Point[] textureCoordinates;
int[] triangleIndices;
contourHelper.ContourFacet(
mesh.TriangleIndices[i],
mesh.TriangleIndices[i + 1],
mesh.TriangleIndices[i + 2],
out positions,
out normals,
out textureCoordinates,
out triangleIndices);
segments.AddRange(positions);
}
return(segments);
}
private void Contour(MeshGeometry3D mesh)
{
var ch = new ContourHelper(origin, normal, mesh);
ch.ContourFacet(0, 1, 2, out newPositions, out newNormals, out newTextureCoordinates, out triangleIndices);
}
private void Contour(MeshGeometry3D mesh)
{
var ch = new ContourHelper(origin, normal, mesh);
ch.ContourFacet(0, 1, 2, out newPositions, out newNormals, out newTextureCoordinates, out triangleIndices);
}
/// <summary>
/// Cuts the mesh with the specified plane.
/// </summary>
/// <param name="mesh">
/// The mesh.
/// </param>
/// <param name="plane">
/// The plane origin.
/// </param>
/// <param name="normal">
/// The plane normal.
/// </param>
/// <returns>
/// The <see cref="MeshGeometry3D"/>.
/// </returns>
public static MeshGeometry3D Cut(this MeshGeometry3D mesh, Point3D plane, Vector3D normal)
{
var hasTextureCoordinates = mesh.TextureCoordinates != null && mesh.TextureCoordinates.Count > 0;
var hasNormals = mesh.Normals != null && mesh.Normals.Count > 0;
var meshBuilder = new MeshBuilder(hasNormals, hasTextureCoordinates);
var contourHelper = new ContourHelper(plane, normal, mesh);
foreach (var position in mesh.Positions)
{
meshBuilder.Positions.Add(position);
}
if (hasTextureCoordinates)
{
foreach (var textureCoordinate in mesh.TextureCoordinates)
{
meshBuilder.TextureCoordinates.Add(textureCoordinate);
}
}
if (hasNormals)
{
foreach (var n in mesh.Normals)
{
meshBuilder.Normals.Add(n);
}
}
for (var i = 0; i < mesh.TriangleIndices.Count; i += 3)
{
var index0 = mesh.TriangleIndices[i];
var index1 = mesh.TriangleIndices[i + 1];
var index2 = mesh.TriangleIndices[i + 2];
Point3D[] positions;
Vector3D[] normals;
Point[] textureCoordinates;
int[] triangleIndices;
contourHelper.ContourFacet(index0, index1, index2, out positions, out normals, out textureCoordinates, out triangleIndices);
foreach (var p in positions)
{
meshBuilder.Positions.Add(p);
}
foreach (var tc in textureCoordinates)
{
meshBuilder.TextureCoordinates.Add(tc);
}
foreach (var n in normals)
{
meshBuilder.Normals.Add(n);
}
foreach (var ti in triangleIndices)
{
meshBuilder.TriangleIndices.Add(ti);
}
}
return(meshBuilder.ToMesh());
}
/// <summary>
/// Cuts the mesh with the specified plane.
/// </summary>
/// <param name="mesh">
/// The mesh.
/// </param>
/// <param name="p">
/// The plane origin.
/// </param>
/// <param name="n">
/// The plane normal.
/// </param>
/// <returns>
/// The <see cref="MeshGeometry3D"/>.
/// </returns>
public static MeshGeometry3D Cut(MeshGeometry3D mesh, Point3D p, Vector3D n)
{
var ch = new ContourHelper(p, n);
var mb = new MeshBuilder(false, false);
foreach (var pos in mesh.Positions)
{
mb.Positions.Add(pos);
}
int j = mb.Positions.Count;
for (int i = 0; i < mesh.TriangleIndices.Count; i += 3)
{
int i0 = mesh.TriangleIndices[i];
int i1 = mesh.TriangleIndices[i + 1];
int i2 = mesh.TriangleIndices[i + 2];
var p0 = mesh.Positions[i0];
var p1 = mesh.Positions[i1];
var p2 = mesh.Positions[i2];
Point3D s0, s1;
int r = ch.ContourFacet(p0, p1, p2, out s0, out s1);
switch (r)
{
case -1:
mb.TriangleIndices.Add(i0);
mb.TriangleIndices.Add(i1);
mb.TriangleIndices.Add(i2);
break;
case 0:
mb.Positions.Add(s1);
mb.Positions.Add(s0);
mb.TriangleIndices.Add(i0);
mb.TriangleIndices.Add(j++);
mb.TriangleIndices.Add(j++);
break;
case 1:
mb.Positions.Add(s0);
mb.Positions.Add(s1);
mb.TriangleIndices.Add(i1);
mb.TriangleIndices.Add(j++);
mb.TriangleIndices.Add(j++);
break;
case 2:
mb.Positions.Add(s0);
mb.Positions.Add(s1);
mb.TriangleIndices.Add(i2);
mb.TriangleIndices.Add(j++);
mb.TriangleIndices.Add(j++);
break;
case 10:
mb.Positions.Add(s0);
mb.Positions.Add(s1);
mb.TriangleIndices.Add(i1);
mb.TriangleIndices.Add(i2);
mb.TriangleIndices.Add(j);
mb.TriangleIndices.Add(j++);
mb.TriangleIndices.Add(j++);
mb.TriangleIndices.Add(i1);
break;
case 11:
mb.Positions.Add(s1);
mb.Positions.Add(s0);
mb.TriangleIndices.Add(i2);
mb.TriangleIndices.Add(i0);
mb.TriangleIndices.Add(j);
mb.TriangleIndices.Add(j++);
mb.TriangleIndices.Add(j++);
mb.TriangleIndices.Add(i2);
break;
case 12:
mb.Positions.Add(s1);
mb.Positions.Add(s0);
mb.TriangleIndices.Add(i0);
mb.TriangleIndices.Add(i1);
mb.TriangleIndices.Add(j);
mb.TriangleIndices.Add(j++);
mb.TriangleIndices.Add(j++);
mb.TriangleIndices.Add(i0);
break;
}
}
// begin bonghi: this is different from the original HelixToolkit version
if (mb.TriangleIndices.Count == 0)
{
return(new MeshGeometry3D());
}
// end bonghi
return(mb.ToMesh());
}
