将三维点转换为二维点

import numpy as np
import OpenGL.GL as gl

def project_3d_to_2d(point_3d):
    modelview = gl.glGetFloatv(gl.GL_MODELVIEW_MATRIX)
    projection = gl.glGetFloatv(gl.GL_PROJECTION_MATRIX)
    viewport = gl.glGetIntegerv(gl.GL_VIEWPORT)
    
    point_3d = np.array([point_3d[0], point_3d[1], point_3d[2], 1.0])  # Homogeneous coordinates
    
    point_2d = np.dot(modelview, point_3d)
    point_2d = np.dot(projection, point_2d)
    
    point_2d /= point_2d[3]  # Perspective division
    
    # Map x, y coordinates to viewport
    point_2d[0] = (point_2d[0] + 1) * viewport[2] / 2 + viewport[0]
    point_2d[1] = (point_2d[1] + 1) * viewport[3] / 2 + viewport[1]
    
    return point_2d[:2]  # Return only x, y coordinates