如何从 polydata 实例中获取积分？

Question

像下面的代码，
当我们创建 vtkPolyData()(:here, polydata) 的实例时，
我们使用 SetPoints(points) 来分配点。

然后，当我这次想要获得积分（：vtkPoints（）的一个实例）时，
我应该为 polydata(:an instance of vtkPolyData()) 做什么？

def points2actor(xyz, apoint_size):
    import vtk
    points = vtk.vtkPoints()
    # Create the topology of the point (a vertex)
    vertices = vtk.vtkCellArray()
    # Add points
    for i in range(0, len(xyz)):
        p = xyz.loc[i].values.tolist()
        point_id = points.InsertNextPoint(p)
        vertices.InsertNextCell(1)
        vertices.InsertCellPoint(point_id)
    # Create a poly data object
    polydata = vtk.vtkPolyData()
    # Set the points and vertices we created as the geometry and topology of the polydata
    polydata.SetPoints(points)
    polydata.SetVerts(vertices)
    polydata.Modified()
    # Mapper for points
    mapper = vtk.vtkPolyDataMapper()
    mapper.SetInput(polydata)
    # ACTOR for points
    actor = vtk.vtkActor()
    actor.SetMapper(mapper)
    actor.GetProperty().SetPointSize(apoint_size)
    return actor, polydata

Answer 1

根据您计划对数据执行的操作，将它们加载到 numpy 数组中可能是最有效的：

from vtk.util import numpy_support

src_points = numpy_support.vtk_to_numpy(polydata.GetPoints().GetData())

python 的内置帮助对于 VTK 也非常有用。

import vtk
polydata = vtk.vtkPolyData()

help(vtk)
help(polydata)

Answer 2

points = polydata.GetPoints()

没有 python 文档，但 cpp API 是相同的：

• https://vtk.org/doc/nightly/html/classvtkPolyData-members.html

• https://vtk.org/doc/nightly/html/classvtkPointSet.html#af8a9a39d0ff4c56454be8d35a42b7f34