openGL +python 鼠标拖动画矩形框选出点云数据的感兴趣区域代码

以下是使用OpenGL和Python实现鼠标拖动画矩形框选出点云数据感兴趣区域的示例代码：

import numpy as np
import glfw
from OpenGL.GL import *

# 生成测试点云数据
n_points = 1000
points = np.random.rand(n_points, 2)

# 定义全局变量
start_pos = None
end_pos = None

# 窗口大小回调函数
def framebuffer_size_callback(window, width, height):
    glViewport(0, 0, width, height)

# 鼠标回调函数
def mouse_button_callback(window, button, action, mods):
    global start_pos, end_pos
    if button == glfw.MOUSE_BUTTON_LEFT and action == glfw.PRESS:
        x, y = glfw.get_cursor_pos(window)
        start_pos = np.array([x, y])
        end_pos = np.array([x, y])
    elif button == glfw.MOUSE_BUTTON_LEFT and action == glfw.RELEASE:
        start_pos = None
        end_pos = None

# 鼠标移动回调函数
def cursor_pos_callback(window, x, y):
    global end_pos
    if start_pos is not None:
        end_pos = np.array([x, y])

# 绘制函数
def render():
    glClear(GL_COLOR_BUFFER_BIT)
    glColor3f(1.0, 1.0, 1.0)
    glPointSize(2.0)
    glBegin(GL_POINTS)
    for i in range(n_points):
        glVertex2f(points[i, 0], points[i, 1])
    glEnd()
    if start_pos is not None and end_pos is not None:
        x0, y0 = start_pos
        x1, y1 = end_pos
        glColor3f(1.0, 0.0, 0.0)
        glBegin(GL_LINE_LOOP)
        glVertex2f(x0, y0)
        glVertex2f(x1, y0)
        glVertex2f(x1, y1)
        glVertex2f(x0, y1)
        glEnd()

# 主函数
def main():
    # 初始化GLFW
    if not glfw.init():
        return

    # 创建窗口
    window = glfw.create_window(800, 600, "OpenGL Window", None, None)
    if not window:
        glfw.terminate()
        return

    # 设置回调函数
    glfw.set_framebuffer_size_callback(window, framebuffer_size_callback)
    glfw.set_mouse_button_callback(window, mouse_button_callback)
    glfw.set_cursor_pos_callback(window, cursor_pos_callback)

    # 设置OpenGL上下文
    glfw.make_context_current(window)

    # 循环渲染
    while not glfw.window_should_close(window):
        # 渲染
        render()

        # 交换缓冲区
        glfw.swap_buffers(window)

        # 处理事件
        glfw.poll_events()

    # 终止GLFW
    glfw.terminate()

if __name__ == '__main__':
    main()

该示例代码使用OpenGL绘制点云数据，并实现了鼠标拖动画矩形框选出感兴趣区域的功能。在主函数中，首先生成了随机的点云数据，然后创建窗口并设置回调函数。在绘制函数中，使用`glBegin()`和`glEnd()`函数绘制点云数据和矩形框选区域。在鼠标回调函数和鼠标移动回调函数中，记录鼠标按下和抬起的位置，并根据鼠标移动的位置更新矩形框选区域的位置。最后，在主函数中循环渲染窗口和处理事件。