当我 select vtk window 中的一个框时，我可以将什么样的 vtk.vtkCommand 事件作为观察者？

Question

我正在尝试找到一种方法来检测我何时结束在 vtk 中制作一个盒子 window。为了允许选择，我首先按下键盘上的 'r'，然后我可以用鼠标左键在 window 上创建一个框。我试图向 MouseInteractorHighLightActor class 添加一个观察者，但我找不到正确的 vtk.vtkCommand 事件来触发我的功能。有人知道我应该使用哪一个吗？

import vtk

class MouseInteractorHighLightActor(vtk.vtkInteractorStyleRubberBandPick):

    def __init__(self, parent=None):
        self.AddObserver(vtk.vtkCommand.EndPickEvent, self.EndPickEventfunc)
        self.AddObserver(vtk.vtkCommand.PickEvent, self.PickEvent)
        self.AddObserver(vtk.vtkCommand.KeyPressEvent, self.KeypressCallbackFunction)
        return

    def KeypressCallbackFunction(self, obj, event):
        print('Key pressed!')

    def PickEvent(self, obj, event):
        print('PickEvent!')

    def EndPickEventfunc(self, obj, event):
        print('I was here!')
        clickPos = self.GetInteractor().GetEventPosition()


# A renderer and render window
renderer = vtk.vtkRenderer()
renderer.SetBackground(.3, .4, .5)

renwin = vtk.vtkRenderWindow()
renwin.AddRenderer(renderer)

# An interactor
interactor = vtk.vtkRenderWindowInteractor()
interactor.SetRenderWindow(renwin)

# add the custom style
style = MouseInteractorHighLightActor()
style.SetDefaultRenderer(renderer)
interactor.SetInteractorStyle(style)

# Add spheres to play with
for i in range(10):
    source = vtk.vtkSphereSource()

    source.SetRadius(vtk.vtkMath.Random(.5, 1.0))
    source.SetCenter(vtk.vtkMath.Random(-5, 5), vtk.vtkMath.Random(-5, 5), vtk.vtkMath.Random(-5, 5))
    source.SetPhiResolution(11)
    source.SetThetaResolution(21)

    mapper = vtk.vtkPolyDataMapper()
    mapper.SetInputConnection(source.GetOutputPort())
    actor = vtk.vtkActor()
    actor.SetMapper(mapper)

    actor.GetProperty().SetDiffuseColor(vtk.vtkMath.Random(.4, 1.0), vtk.vtkMath.Random(.4, 1.0), vtk.vtkMath.Random(.4, 1.0))

    renderer.AddActor(actor)

# Start
interactor.Initialize()
interactor.Start()

Answer 1

在 vtk.vtkRenderedAreaPicker 上使用 vtk.vtkCommand.EndPickEvent 观察器并将该区域选择器添加到 vtkRenderWindowInteractor

这是执行此操作的代码：

import vtk

class MouseInteractorHighLightActor(vtk.vtkInteractorStyleRubberBandPick):

    def __init__(self, parent=None):
        self.AddObserver(vtk.vtkCommand.PickEvent, self.PickEvent)
        self.AddObserver(vtk.vtkCommand.KeyPressEvent, self.KeypressCallbackFunction)

        self.area_picker = vtk.vtkRenderedAreaPicker()
        self.area_picker.AddObserver(vtk.vtkCommand.EndPickEvent, self.EndPickEventfunc)
        self.area_picker.AddObserver(vtk.vtkCommand.PickEvent, self.PickEvent)
        return

    def KeypressCallbackFunction(self, obj, event):
        print('Key pressed!')

    def PickEvent(self, obj, event):
        print('PickEvent!')

    def EndPickEventfunc(self, obj, event):
        print('I was here!')
        clickPos = self.GetInteractor().GetEventPosition()


# A renderer and render window
renderer = vtk.vtkRenderer()
renderer.SetBackground(.3, .4, .5)

renwin = vtk.vtkRenderWindow()
renwin.AddRenderer(renderer)

# An interactor
interactor = vtk.vtkRenderWindowInteractor()
interactor.SetRenderWindow(renwin)

# add the custom style
style = MouseInteractorHighLightActor()
style.SetDefaultRenderer(renderer)
interactor.SetInteractorStyle(style)
interactor.SetPicker(style.area_picker)


# Add spheres to play with
for i in range(10):
    source = vtk.vtkSphereSource()

    source.SetRadius(vtk.vtkMath.Random(.5, 1.0))
    source.SetCenter(vtk.vtkMath.Random(-5, 5), vtk.vtkMath.Random(-5, 5), vtk.vtkMath.Random(-5, 5))
    source.SetPhiResolution(11)
    source.SetThetaResolution(21)

    mapper = vtk.vtkPolyDataMapper()
    mapper.SetInputConnection(source.GetOutputPort())
    actor = vtk.vtkActor()
    actor.SetMapper(mapper)

    actor.GetProperty().SetDiffuseColor(vtk.vtkMath.Random(.4, 1.0), vtk.vtkMath.Random(.4, 1.0), vtk.vtkMath.Random(.4, 1.0))

    renderer.AddActor(actor)

# Start
interactor.Initialize()
interactor.Start()

PyVista 使这种方式更容易

结帐 PyVista：https://docs.pyvista.org

import pyvista as pv
import numpy as np

spheres = pv.MultiBlock()
for i in range(10):
    spheres.append(pv.Sphere(radius=(i + 5) / 10, 
                             center=np.random.rand(3) * 5))

plotter = pv.Plotter(notebook=0)
for i in range(10):
    sphere = pv.Sphere(radius=(i) / 10, 
                       center=np.random.rand(3) * 10 - 5)
    plotter.add_mesh(sphere)

def k_button():
    print("K key pressed")

def picking(mesh):
    print("Some stuff was picked")

plotter.add_key_event("k", k_button)
plotter.enable_cell_picking(callback=picking, through=False)
plotter.show()

当我 select vtk window 中的一个框时，我可以将什么样的 vtk.vtkCommand 事件作为观察者？

What kind of vtk.vtkCommand event I can put as Observer when I select a box in a vtk window?

python

events

vtk

PyVista 使这种方式更容易