python - 在 Paraview 中的 3D 体积上叠加线图

Question

我想在提取数据的线上可视化线图(从沿着模型“表面”的线过滤器上的图提取)。 Plot Over Line 过滤器允许通过数据值对线进行着色，并进行较小的转换，但我想将 Z 位置设置为数据值的乘数。

这是基本图像，没有用数据值乘以直线的 Z:

我导出了线图数据，将数据值(让我们称之为幅度)转换为伪高程，并将结果导入为 x、y、z 点集(其中 x、y 是水平坐标，z = 表示为高程坐标的幅度)。

如何沿着这些点绘制曲线？在不应用任何过滤器的情况下，它只是绘制为空间中的一系列点。

还有别的办法吗？我敢肯定这很简单，但我看不到。

Answer 1

修改自问题How to connect points in paraview?使用 ' Transform the input ' Paraview 公共(public) Wiki 页面中关于可编程 python 过滤器的示例，以及 vtk docs :

pdi = self.GetPolyDataInput()
pdo =  self.GetPolyDataOutput()
numPoints = pdi.GetNumberOfPoints()
pdo.Allocate()
for i in range(0, numPoints-1):
    points = [i, i+1]
    # VTK_LINE is 3
    pdo.InsertNextCell(3, 2, points)

或者，这里有另一个脚本可以完成类似的工作，它是根据与上一个示例相同页面上的几个其他示例修改而来的:

# Get a vtk.PolyData object for the input
pdi = self.GetPolyDataInput()
# Get a vtk.PolyData object for the output
pdo = self.GetPolyDataOutput()

numPoints = pdi.GetNumberOfPoints()

# Points for the line:
newPoints = vtk.vtkPoints()
for i in range(0, numPoints):
    # Generate the new points from the input
    coord = pdi.GetPoint(i)
    x, y, z = coord[:3]
    newPoints.InsertPoint(i, x, y, z)

# Add the new points to the PolyData object:
pdo.SetPoints(newPoints)

# Make a line from the new points:
aPolyLine = vtk.vtkPolyLine()

#Indicate the number of points along the line
aPolyLine.GetPointIds().SetNumberOfIds(numPoints)
for i in range(0,numPoints):
   #Add the points to the line. The first value indicates
   #the order of the point on the line. The second value
   #is a reference to a point in a vtkPoints object. Depends
   #on the order that Points were added to vtkPoints object.
   #Note that this will not be associated with actual points
   #until it is added to a vtkPolyData object which holds a
   #vtkPoints object.
   aPolyLine.GetPointIds().SetId(i, i)

#Allocate the number of 'cells' that will be added. We are just
#adding one vtkPolyLine 'cell' to the vtkPolyData object.
pdo.Allocate(1, 1)

#Add the poly line 'cell' to the vtkPolyData object.
pdo.InsertNextCell(aPolyLine.GetCellType(), aPolyLine.GetPointIds())

两种解决方案都会产生这样的图像(在对“属性”面板进行一些调整之后):