Question

我需要在python中用固体四面体写一个xml vtk文件。特别是在Polydata中。我有一组四面体，每条边有x，y，z坐标。我尝试使用vtk.vtkXMLPolyDataWriter（），但我得到了这个（只有2D三角形）：

我的代码：

#!/usr/bin/env python
import vtk

points = vtk.vtkPoints()
points.InsertNextPoint(0, 0, 0)
points.InsertNextPoint(1, 0, 0)
points.InsertNextPoint(1, 1, 0)
points.InsertNextPoint(0, 1, 1)

tetra = vtk.vtkTetra()

tetra.GetPointIds().SetId(0, 0)
tetra.GetPointIds().SetId(1, 1)
tetra.GetPointIds().SetId(2, 2)
tetra.GetPointIds().SetId(3, 3)

cellArray = vtk.vtkCellArray()
cellArray.InsertNextCell(tetra)

polydata = vtk.vtkPolyData()
polydata.SetPoints(points)
polydata.SetPolys(cellArray)
polydata.Modified()
if vtk.VTK_MAJOR_VERSION <= 5:
    polydata.Update()

writer = vtk.vtkXMLPolyDataWriter()
writer.SetFileName("Primal_geo.vtp");
if vtk.VTK_MAJOR_VERSION <= 5:
    writer.SetInput(polydata)
else:
    writer.SetInputData(polydata)
writer.Write()

那么，我怎么写这个文件？谢谢！

Answer 1

XML is information in tags。这是一种自由的手json。所以我们走了。

现在让我首先说我不熟悉vtk或它的功能，所以虽然我希望我在这里提供的代码符合您的目的，但我不确定是否存在更令人满意的（预先存在的vtk片段）。

那说我写了这个小东西。

#!/usr/bin/env python
import vtk

class vtkXMLparser:
    points = None
    scellArray = None
    def tagSplit(self,line):
        for n,k in enumerate(line):
            go = none
            fin = none
            if(k == ">"):
                if(go == none):
                    if(n>0):
                        if(line[n-1]!="\\"):
                            go = n+1
            if(go != none):
                if(k == "<"):
                    if(n>0):
                        if(line[n-1]!="\\"):
                            if(n<len(line)-1):
                                if(line[n+1]=="/"):
                                    fin = n+1
        tag = line[fin+2:len(line)-1]
        content = line[go:fin]
        return([tag,content])

    def addNice(self,di,key,cont):
        try:
            di[key].append(cont)
        except(KeyError):
            di[key]=[]
            di[key].append(cont)

    def parse(self,f):
        input = open(f,"r")
        xml = input.read() 
        xml = xml.split("\n")
        data = {}
        for lineNumber,line in enumerate(xml):
            parsedXmlLine = self.tagSplit(line)
            self.addNice(data,parsedXmlLine[0],parsedXmlLine[1])
        self.self.points(data)
        self.tetra(data)
        self.write()

    def self.points(self,di):
        self.points = vtk.vtkself.points()
        for point in di["point"]:
            self.points.InsertNextPoint(eval(point))

    def tetra(self,di):
        tetra = vtk.vtkTetra()
        for id in di["tetra"]:
            tetra.GetPointIds().SetId(eval(id))
        self.cellArray = vtk.vtkself.cellArray()
        self.cellArray.InsertNextCell(tetra)

    def write(self):
        polydata = vtk.vtkPolyData()
        polydata.Setself.points(self.points)
        polydata.SetPolys(self.cellArray)
        polydata.Modified()
        if vtk.VTK_MAJOR_VERSION <= 5:
            polydata.Update()
        writer = vtk.vtkXMLPolyDataWriter()
        writer.SetFileName("Primal_geo.vtp");
        if vtk.VTK_MAJOR_VERSION <= 5:
            writer.SetInput(polydata)
        else:
            writer.SetInputData(polydata)
        writer.Write()

i = vtkXMLparser()
i.parse("input.xml")

我会为你的例子编写一个看起来像这样的输入文件。

<point>0, 0, 0</point>
<point>1, 0, 0</point>
<point>1, 1, 0</point>
<point>0, 1, 1</point>

<tetra>0, 0</tetra>
<tetra>1, 1</tetra>
<tetra>2, 2</tetra>
<tetra>3, 3</tetra>

我希望这有帮助！

python vtk XMLPolyDataWriter写实心四面体

1 个答案: