给出一个模型，用python代码实现自动纹理映射，其中模型文件名称为model.obj

好的，我可以给你提供一个基于Python的纹理映射示例代码，代码中使用了PyOpenGL和PyWavefront库来读取和渲染3D模型，实现自动纹理映射。代码如下：

import pywavefront
import OpenGL.GL as gl
import OpenGL.GLU as glu
import OpenGL.GLUT as glut
import cv2

model = pywavefront.Wavefront('model.obj')
texture = cv2.imread('texture.jpg')

def init():
    gl.glClearColor(1.0, 1.0, 1.0, 0.0)
    gl.glEnable(gl.GL_DEPTH_TEST)
    gl.glEnable(gl.GL_TEXTURE_2D)

def display():
    gl.glClear(gl.GL_COLOR_BUFFER_BIT|gl.GL_DEPTH_BUFFER_BIT)
    gl.glLoadIdentity()

    gl.glTranslatef(0.0, 0.0, -10.0)

    gl.glBegin(gl.GL_TRIANGLES)
    for name, material in model.materials.items():
        gl.glColor(material.diffuse)
        for face in model.groups[name]:
            if len(face) == 3:
                for vertex_i in range(3):
                    vertex_index = face[vertex_i]
                    vertex = model.vertices[vertex_index]
                    texture_coord = model.texcoords[vertex_i][vertex_index]
                    gl.glTexCoord2f(*texture_coord)
                    gl.glVertex3f(*vertex)
    gl.glEnd()

    glut.glutSwapBuffers()

def reshape(width, height):
    gl.glViewport(0, 0, width, height)
    gl.glMatrixMode(gl.GL_PROJECTION)
    gl.glLoadIdentity()
    glu.gluPerspective(60.0, float(width)/height, 0.1, 100.0)
    gl.glMatrixMode(gl.GL_MODELVIEW)

def main():
    glut.glutInit()
    glut.glutInitDisplayMode(glut.GLUT_DOUBLE|glut.GLUT_RGBA|glut.GLUT_DEPTH)
    glut.glutCreateWindow("Texture Mapping")
    glut.glutReshapeWindow(640, 480)

    init()

    gl.glTexImage2D(gl.GL_TEXTURE_2D, 0, gl.GL_RGB, texture.shape[1], texture.shape[0], 0, gl.GL_BGR, gl.GL_UNSIGNED_BYTE, texture)
    gl.glTexParameterf(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_WRAP_S, gl.GL_REPEAT)
    gl.glTexParameterf(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_WRAP_T, gl.GL_REPEAT)
    gl.glTexParameterf(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_MAG_FILTER, gl.GL_NEAREST)
    gl.glTexParameterf(gl.GL_TEXTURE_2D, gl.GL_TEXTURE_MIN_FILTER, gl.GL_NEAREST)

    glut.glutDisplayFunc(display)
    glut.glutReshapeFunc(reshape)
    glut.glutMainLoop()

if __name__ == '__main__':
    main()

你需要将上述代码中的模型文件名和纹理文件名替换为你自己的文件名，然后运行代码即可。