VTK，（visualizationtoolkit）是一個開放資源的免費軟件系統(tǒng)，主要用于三維計算機圖形學、圖像處理和可視化。Vtk是在面向對象原理的基礎上設計和實現的，它的內核是用C++構建的，包含有大約250,000行代碼，2000多個類，還包含有幾個轉換界面，因此也可以自由的通過Java，Tcl/Tk和Python各種語言使用vtk。

主要函數介紹：

NewPickedActor.GetProperty()： 通過該函數，可以設置actor的性質，如顏色、表面樣式等。

vtk.vtkSphereSource()： 創(chuàng)建球體的函數，文中通過一個for循環(huán)創(chuàng)建了10個球體。

vtk.vtkMinimalStandardRandomSequence()： VTK的隨機數生成器，用于代碼中的十個球體，隨機生成球體的大小和位置。

MouseInteractorHighLightActor： 定義actor操作方法，這個是一個鼠標操作控件的控制方法。

leftButtonPressEvent(self, obj, event)： 這是一個事件觸發(fā)函數，當鼠標左鍵點擊對應的actor時，會觸發(fā)函數，對點的actor高亮顯示。

主要代碼如下：

#!/usr/bin/env python

# noinspection PyUnresolvedReferences
import vtk

colors = vtk.vtkNamedColors()
NUMBER_OF_SPHERES = 10


class MouseInteractorHighLightActor(vtk.vtkInteractorStyleTrackballCamera):

    def __init__(self, parent=None):
        self.AddObserver("LeftButtonPressEvent", self.leftButtonPressEvent)

        self.LastPickedActor = None
        self.LastPickedProperty = vtk.vtkProperty()

    def leftButtonPressEvent(self, obj, event):
        clickPos = self.GetInteractor().GetEventPosition()

        picker = vtk.vtkPropPicker()
        picker.Pick(clickPos[0], clickPos[1], 0, self.GetDefaultRenderer())

        # 創(chuàng)建一個新的actor
        self.NewPickedActor = picker.GetActor()

        # If something was selected
        if self.NewPickedActor:
            # If we picked something before, reset its property
            if self.LastPickedActor:
                self.LastPickedActor.GetProperty().DeepCopy(self.LastPickedProperty)

            # Save the property of the picked actor so that we can
            # restore it next time
            self.LastPickedProperty.DeepCopy(self.NewPickedActor.GetProperty())
            # 高亮選中球體，并顯示邊緣
            self.NewPickedActor.GetProperty().SetColor(colors.GetColor3d('Red'))
            self.NewPickedActor.GetProperty().SetDiffuse(1.0)
            self.NewPickedActor.GetProperty().SetSpecular(0.0)
            self.NewPickedActor.GetProperty().EdgeVisibilityOn()

            # 保存最后一個選中的actor
            self.LastPickedActor = self.NewPickedActor

        self.OnLeftButtonDown()
        return


def main():
    # 創(chuàng)建render和window
    renderer = vtk.vtkRenderer()
    renderer.SetBackground(colors.GetColor3d('SteelBlue'))

    renwin = vtk.vtkRenderWindow()
    renwin.AddRenderer(renderer)
    renwin.SetSize(640, 480)
    renwin.SetWindowName('HighlightPickedActor')

    # 建立interactor(交互操作)
    interactor = vtk.vtkRenderWindowInteractor()
    interactor.SetRenderWindow(renwin)

    # 交互操作方法
    style = MouseInteractorHighLightActor()
    style.SetDefaultRenderer(renderer)
    interactor.SetInteractorStyle(style)

    randomSequence = vtk.vtkMinimalStandardRandomSequence()
    # randomSequence.SetSeed(1043618065)
    # randomSequence.SetSeed(5170)
    randomSequence.SetSeed(8775070)
    # 添加球體
    for i in range(NUMBER_OF_SPHERES):
        source = vtk.vtkSphereSource()

        # random position and radius
        x = randomSequence.GetRangeValue(-5.0, 5.0)
        randomSequence.Next()
        y = randomSequence.GetRangeValue(-5.0, 5.0)
        randomSequence.Next()
        z = randomSequence.GetRangeValue(-5.0, 5.0)
        randomSequence.Next()
        radius = randomSequence.GetRangeValue(0.5, 1.0)
        randomSequence.Next()

        source.SetRadius(radius)
        source.SetCenter(x, y, z)
        source.SetPhiResolution(11)
        source.SetThetaResolution(21)

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

        r = randomSequence.GetRangeValue(0.4, 1.0)
        randomSequence.Next()
        g = randomSequence.GetRangeValue(0.4, 1.0)
        randomSequence.Next()
        b = randomSequence.GetRangeValue(0.4, 1.0)
        randomSequence.Next()

        actor.GetProperty().SetDiffuseColor(r, g, b)
        actor.GetProperty().SetDiffuse(.8)
        actor.GetProperty().SetSpecular(.5)
        actor.GetProperty().SetSpecularColor(colors.GetColor3d('White'))
        actor.GetProperty().SetSpecularPower(30.0)

        renderer.AddActor(actor)

    # 運行
    interactor.Initialize()
    renwin.Render()
    interactor.Start()


if __name__ == '__main__':
    main()

顯示結果如下：未選擇球體：