VTK如何动态设置相机的角度和位置（python）

我们可以通过自定义交互方式来控制相机的运动，例如当我们按下一个按键的时候相机向左或者向右移动一定的角度。

这里我们给出一个示例：
本示例完成了一个功能，当我们按下按键a的时候，相机就会自动自动收集不同方向的运动窗口的画面,将对应的相机位置和姿态的信息保存下来

# 自定义交互风格
class myInteractorStyle(vtk.vtkInteractorStyleTrackballCamera):
    def __init__(self, parent=None):
        self.AddObserver('KeyPressEvent', self.onKeyPressE)

        self.left_press = False
        self.start_record = False
        self.reader = None
        self.conActor = None
        self.axes = None
        self.pre_pos = ""
        self.renwin = None
        self.camera = None

    def onKeyPressE(self, obj, event):
        # 获取按下的键
        key = self.GetInteractor().GetKeySym()

        if key == 'a':
            self.auto_change_camera_savedata()
            # print(self.camera.GetOrientation())
        self.OnKeyPress()

    def auto_change_camera_savedata(self):
        print("Recording data".center(60, "="))
        labelfile = f"./dataset/test/label_namexyzear.csv"
        label_txt = open(labelfile, "w+")

        camera_pos = 275 
        render = vtk.vtkRenderer()
        render.AddActor(self.conActor) # 添加 actor
        camera = render.GetActiveCamera() # 获取相机
        self.renwin.AddRenderer(render) # 获取渲染器
        index = 0
        while camera_pos <= 380:
            random_zoom = np.random.randint(0,25) # 随机相机的位置
            camera_pos  += random_zoom 
        
            azi = -180 # 取值范围-180, 180 
            while azi <= 180:
                random_azi = np.random.randint(0,25) 
                azi += random_azi 

                ele = -90 # 取值范围 -90, 90 
                while ele <= 90:
                    random_ele = np.random.randint(0,25) 
                    ele += random_ele 

                    roll = -180 # 取值范围-180, 180
                    while roll <= 180:
                        index  += 1 
                        random_roll = np.random.randint(0,25) 
                        roll += random_roll 

                        camera.SetPosition(0, 0, camera_pos) # 设置相机的位置
                        camera.SetFocalPoint(0,0,0) # 设置相机的焦点
                        camera.Elevation(ele) # 绕X轴旋转 垂直 俯仰角度
                        camera.Azimuth(azi) # 绕Y轴旋转 水平 滚动角
                        camera.Roll(roll) # 绕Z轴旋转 平行 偏航角

                        self.renwin.Render() 

                        # 保存图像和标签
                        imgname = f"./dataset/test/images/{int(time()*1000)+np.random.randint(0,99999)}.jpg"
                        self.save_window_pic(imgname)

                        pos = self.getpos(camera)
                        label_txt.write(f"{imgname},{pos[0]},{pos[1]},{pos[2]},{ele},{-azi},{roll}\n")

                        if index % 500 == 0: print(f"已经收集了{index}张图片")

    def getpos(self, camera):
        pos = list(camera.GetPosition()) 
        return pos
       
    def save_window_pic(self, filename):
        window_to_image_filter = vtk.vtkWindowToImageFilter()
        window_to_image_filter.SetInput(self.renwin) # 获取当前窗口
        window_to_image_filter.SetInputBufferTypeToRGB()
        # window_to_image_filter.Update()

        # writer = vtk.vtkBMPWriter() # 将图片保存为BMP格式
        writer = vtk.vtkJPEGWriter() # 将图片保存为JPEG格式
        writer.SetFileName(filename)
        writer.SetInputConnection(window_to_image_filter.GetOutputPort())
        writer.SetQuality(100)
        writer.Write()

关于动态设置相机的代码在auto_change_camera_savedata函数中。这段代码是一个用于自动采集相机视角的功能。
该函数用于自动改变相机的位置并保存图像和标签。