pyopengl选中物体

要实现选中物体，通常需要进行以下步骤：

1. 确定鼠标点击的位置。
2. 将鼠标点击的位置转换为OpenGL坐标系中的坐标。
3. 遍历场景中的所有物体，并检查哪些物体包含鼠标点击的坐标。
4. 如果找到了包含该坐标的物体，则将其标记为选中状态。

以下是一个基本的选中物体的示例代码：

import glfw
from OpenGL.GL import *
from OpenGL.GLU import *

# 定义场景中的物体
objects = [
    {'name': 'cube1', 'vertices': [(0, 0, 0), (1, 0, 0), (1, 1, 0), (0, 1, 0), (0, 0, 1), (1, 0, 1), (1, 1, 1), (0, 1, 1)], 'color': (1, 0, 0)},
    {'name': 'cube2', 'vertices': [(2, 0, 0), (3, 0, 0), (3, 1, 0), (2, 1, 0), (2, 0, 1), (3, 0, 1), (3, 1, 1), (2, 1, 1)], 'color': (0, 1, 0)},
    {'name': 'cube3', 'vertices': [(0, 2, 0), (1, 2, 0), (1, 3, 0), (0, 3, 0), (0, 2, 1), (1, 2, 1), (1, 3, 1), (0, 3, 1)], 'color': (0, 0, 1)}
]

# 定义选中物体的颜色
selected_color = (1, 1, 1)

# 定义选中的物体
selected_object = None

# 选中物体的函数
def select_object(x, y):
    global selected_object
    viewport = glGetIntegerv(GL_VIEWPORT)
    modelview = glGetDoublev(GL_MODELVIEW_MATRIX)
    projection = glGetDoublev(GL_PROJECTION_MATRIX)
    winx, winy, winz = gluUnProject(x, viewport[3]-y, 0, modelview, projection, viewport)
    for obj in objects:
        vertices = obj['vertices']
        xmin, ymin, zmin = vertices[0]
        xmax, ymax, zmax = vertices[0]
        for vertex in vertices:
            x, y, z = vertex
            if x < xmin:
                xmin = x
            elif x > xmax:
                xmax = x
            if y < ymin:
                ymin = y
            elif y > ymax:
                ymax = y
            if z < zmin:
                zmin = z
            elif z > zmax:
                zmax = z
        if winx >= xmin and winx <= xmax and winy >= ymin and winy <= ymax and winz >= zmin and winz <= zmax:
            selected_object = obj
            obj['color'] = selected_color
        else:
            obj['color'] = tuple([c*0.5 for c in obj['color']])

# 绘制场景的函数
def draw_scene():
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
    glMatrixMode(GL_MODELVIEW)
    glLoadIdentity()
    gluLookAt(0, 0, 5, 0, 0, 0, 0, 1, 0)
    for obj in objects:
        glColor3f(*obj['color'])
        glBegin(GL_QUADS)
        for vertex in obj['vertices']:
            glVertex3f(*vertex)
        glEnd()

# 鼠标点击事件处理函数
def mouse_button_callback(window, button, action, mods):
    if button == glfw.MOUSE_BUTTON_LEFT and action == glfw.PRESS:
        x, y = glfw.get_cursor_pos(window)
        select_object(x, y)

# 主函数
def main():
    if not glfw.init():
        return
    window = glfw.create_window(640, 480, 'Select Object', None, None)
    if not window:
        glfw.terminate()
        return
    glfw.make_context_current(window)
    glfw.set_mouse_button_callback(window, mouse_button_callback)
    glEnable(GL_DEPTH_TEST)
    while not glfw.window_should_close(window):
        draw_scene()
        glfw.swap_buffers(window)
        glfw.poll_events()
    glfw.terminate()

if __name__ == '__main__':
    main()

该示例代码定义了三个立方体物体，并将它们分别绘制为红色、绿色和蓝色。当用户点击鼠标左键时，程序将检查鼠标点击的位置，如果该位置包含在某个立方体中，则将该立方体的颜色改为白色，表示该立方体被选中了。如果用户点击另一个立方体，则前一个选中的立方体的颜色将被还原为原来的颜色，新选中的立方体的颜色将被改为白色。