private void QuadricDecimation()
{
vtkSphereSource sphereSource = vtkSphereSource.New();
sphereSource.Update();
vtkPolyData input = vtkPolyData.New();
input.ShallowCopy(sphereSource.GetOutput());
Debug.WriteLine("Before decimation" + Environment.NewLine + "------------");
Debug.WriteLine("There are " + input.GetNumberOfPoints() + " points.");
Debug.WriteLine("There are " + input.GetNumberOfPolys() + " polygons.");
vtkQuadricDecimation decimate = vtkQuadricDecimation.New();
#if VTK_MAJOR_VERSION_5
decimate.SetInputConnection(input.GetProducerPort());
#else
decimate.SetInputData(input);
#endif
decimate.Update();
vtkPolyData decimated = vtkPolyData.New();
decimated.ShallowCopy(decimate.GetOutput());
Debug.WriteLine("After decimation" + Environment.NewLine + "------------");
Debug.WriteLine("There are " + decimated.GetNumberOfPoints() + " points.");
Debug.WriteLine("There are " + decimated.GetNumberOfPolys() + " polygons.");
vtkPolyDataMapper inputMapper = vtkPolyDataMapper.New();
#if VTK_MAJOR_VERSION_5
inputMapper.SetInputConnection(input.GetProducerPort());
#else
inputMapper.SetInputData(input);
#endif
vtkActor inputActor = vtkActor.New();
inputActor.SetMapper(inputMapper);
vtkPolyDataMapper decimatedMapper = vtkPolyDataMapper.New();
#if VTK_MAJOR_VERSION_5
decimatedMapper.SetInputConnection(decimated.GetProducerPort());
#else
decimatedMapper.SetInputData(decimated);
#endif
vtkActor decimatedActor = vtkActor.New();
decimatedActor.SetMapper(decimatedMapper);
vtkRenderWindow renderWindow = renderWindowControl1.RenderWindow;
this.Size = new System.Drawing.Size(612, 352);
// Define viewport ranges
// (xmin, ymin, xmax, ymax)
double[] leftViewport = new double[] { 0.0, 0.0, 0.5, 1.0 };
double[] rightViewport = new double[] { 0.5, 0.0, 1.0, 1.0 };
// Setup both renderers
vtkRenderer leftRenderer = vtkRenderer.New();
renderWindow.AddRenderer(leftRenderer);
leftRenderer.SetViewport(leftViewport[0], leftViewport[1], leftViewport[2], leftViewport[3]);
leftRenderer.SetBackground(.6, .5, .4);
vtkRenderer rightRenderer = vtkRenderer.New();
renderWindow.AddRenderer(rightRenderer);
rightRenderer.SetViewport(rightViewport[0], rightViewport[1], rightViewport[2], rightViewport[3]);
rightRenderer.SetBackground(.4, .5, .6);
// Add the sphere to the left and the cube to the right
leftRenderer.AddActor(inputActor);
rightRenderer.AddActor(decimatedActor);
leftRenderer.ResetCamera();
rightRenderer.ResetCamera();
renderWindow.Render();
}
/// <summary>
/// Generates a Unity Mesh from a vtkPolyData.
/// </summary>
/// <param name="pd">The vtk poly data.</param>
/// <returns>The Unity Mesh (without colors).</returns>
private static Mesh PolyDataToMesh(vtkPolyData pd)
{
if (pd == null)
{
Debug.LogWarning("No PolyData passed!");
return null;
}
var numVertices = pd.GetNumberOfPoints();
if (numVertices == 0)
{
Debug.LogWarning("No vertices to convert!");
return null;
}
var mesh = new Mesh();
// Points / Vertices
var vertices = new Vector3[numVertices];
for (var i = 0; i < numVertices; ++i)
{
var pnt = pd.GetPoint(i);
// Flip z-up to y-up
vertices[i] = new Vector3(-(float) pnt[0], (float) pnt[2], (float) pnt[1]);
}
mesh.vertices = vertices;
// Normals
var vtkNormals = pd.GetPointData().GetNormals();
if (vtkNormals != null)
{
var numNormals = vtkNormals.GetNumberOfTuples();
var normals = new Vector3[numNormals];
for (var i = 0; i < numNormals; i++)
{
var normal = vtkNormals.GetTuple3(i);
// flip normals ?
normals[i] = new Vector3(-(float) normal[0], -(float) normal[1], -(float) normal[2]);
}
mesh.normals = normals;
}
else
{
Debug.Log("No Normals!");
}
// Texture coordinates
var vtkTexCoords = pd.GetPointData().GetTCoords();
if (vtkTexCoords != null)
{
var numCoords = vtkTexCoords.GetNumberOfTuples();
var uvs = new Vector2[numCoords];
for (var i = 0; i < numCoords; ++i)
{
var texCoords = vtkTexCoords.GetTuple2(i);
uvs[i] = new Vector2((float) texCoords[0], (float) texCoords[1]);
}
mesh.uv = uvs;
}
// Triangles / Cells
var numTriangles = pd.GetNumberOfPolys();
var polys = pd.GetPolys();
if (polys.GetNumberOfCells() > 0)
{
var triangles = new int[numTriangles*3];
var prim = 0;
var pts = vtkIdList.New();
polys.InitTraversal();
while (polys.GetNextCell(pts) != 0)
{
for (var i = 0; i < pts.GetNumberOfIds(); ++i)
triangles[prim*3 + i] = pts.GetId(i);
++prim;
}
mesh.SetTriangles(triangles, 0);
//Mesh.RecalculateNormals();
mesh.RecalculateBounds();
return mesh;
}
// Lines
var lines = pd.GetLines();
if (lines.GetNumberOfCells() > 0)
{
var idList = new ArrayList();
var pts = vtkIdList.New();
lines.InitTraversal();
while (lines.GetNextCell(pts) != 0)
{
for (var i = 0; i < pts.GetNumberOfIds() - 1; ++i)
{
idList.Add(pts.GetId(i));
idList.Add(pts.GetId(i + 1));
}
}
mesh.SetIndices(idList.ToArray(typeof (int)) as int[], MeshTopology.Lines, 0);
mesh.RecalculateBounds();
return mesh;
}
// Points
var points = pd.GetVerts();
var numPointCells = points.GetNumberOfCells();
if (numPointCells > 0)
{
var idList = new ArrayList();
var pts = vtkIdList.New();
points.InitTraversal();
while (points.GetNextCell(pts) != 0)
{
for (int i = 0; i < pts.GetNumberOfIds(); ++i)
{
idList.Add(pts.GetId(i));
}
}
mesh.SetIndices(idList.ToArray(typeof (int)) as int[], MeshTopology.Points, 0);
mesh.RecalculateBounds();
}
return mesh;
}
