Python实现立方体纹理映射

本文要点在于扩展库pyopengl的使用，接口与标准的OpenGL基本一致。

import sys

from OpenGL.GL import *

from OpenGL.GLUT import *

from OpenGL.GLU import *

from PIL import Image

class MyPyOpenGLTest:

#初始化OpenGL环境

def __init__(self, width = 640, height = 480, title = b'MyPyOpenGLTest'):

glutInit(sys.argv)

glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE | GLUT_DEPTH)

glutInitWindowSize(width, height)

self.window = glutCreateWindow(title)

glutDisplayFunc(self.Draw)

glutIdleFunc(self.Draw)

self.InitGL(width, height)

#绕各坐标轴旋转的角度

self.x = 0.0

self.y = 0.0

self.z = 0.0

#绘制图形

def Draw(self):

glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)

glLoadIdentity()

#沿z轴平移

glTranslate(0.0, 0.0, -5.0)

#分别绕x,y,z轴旋转

glRotatef(self.x, 1.0, 0.0, 0.0)

glRotatef(self.y, 0.0, 1.0, 0.0)

glRotatef(self.z, 0.0, 0.0, 1.0)

#开始绘制立方体的每个面，同时设置纹理映射

#绘制四边形

glBegin(GL_QUADS)

#绘制顶点，并设置纹理坐标

glTexCoord2f(0.0, 0.0)

glVertex3f(-1.0, -1.0, 1.0)

glTexCoord2f(1.0, 0.0)

glVertex3f(1.0, -1.0, 1.0)

glTexCoord2f(1.0, 1.0)

glVertex3f(1.0, 1.0, 1.0)

glTexCoord2f(0.0, 1.0)

glVertex3f(-1.0, 1.0, 1.0)

#绘制立方体的第二个面

glTexCoord2f(1.0, 0.0)

glVertex3f(-1.0, -1.0, -1.0)

glTexCoord2f(1.0, 1.0)

glVertex3f(-1.0, 1.0, -1.0)

glTexCoord2f(0.0, 1.0)

glVertex3f(1.0, 1.0, -1.0)

glTexCoord2f(0.0, 0.0)

glVertex3f(1.0, -1.0, -1.0)

#绘制立方体的第三个面

glTexCoord2f(0.0, 1.0)

glVertex3f(-1.0, 1.0, -1.0)

glTexCoord2f(0.0, 0.0)

glVertex3f(-1.0, 1.0, 1.0)

glTexCoord2f(1.0, 0.0)

glVertex3f(1.0, 1.0, 1.0)

glTexCoord2f(1.0, 1.0)

glVertex3f(1.0, 1.0, -1.0)

#绘制立方体的第四个面

glTexCoord2f(1.0, 1.0)

glVertex3f(-1.0, -1.0, -1.0)

glTexCoord2f(0.0, 1.0)

glVertex3f(1.0, -1.0, -1.0)

glTexCoord2f(0.0, 0.0)

glVertex3f(1.0, -1.0, 1.0)

glTexCoord2f(1.0, 0.0)

glVertex3f(-1.0, -1.0, 1.0)

#绘制立方体的第五个面

glTexCoord2f(1.0, 0.0)

glVertex3f(1.0, -1.0, -1.0)

glTexCoord2f(1.0, 1.0)

glVertex3f(1.0, 1.0, -1.0)

glTexCoord2f(0.0, 1.0)

glVertex3f(1.0, 1.0, 1.0)

glTexCoord2f(0.0, 0.0)

glVertex3f(1.0, -1.0, 1.0)

#绘制立方体的第六个面

glTexCoord2f(0.0, 0.0)

glVertex3f(-1.0, -1.0, -1.0)

glTexCoord2f(1.0, 0.0)

glVertex3f(-1.0, -1.0, 1.0)

glTexCoord2f(1.0, 1.0)

glVertex3f(-1.0, 1.0, 1.0)

glTexCoord2f(0.0, 1.0)

glVertex3f(-1.0, 1.0, -1.0)

#结束绘制

glEnd()

#刷新屏幕，产生动画效果

glutSwapBuffers()

#修改各坐标轴的旋转角度

self.x += 0.2

self.y += 0.3

self.z += 0.1

#加载纹理

def LoadTexture(self):

#sample.bmp是纹理图像文件

img = Image.open('sample.bmp')

width, height = img.size

img = img.tobytes('raw', 'RGBX', 0, -1)

glBindTexture(GL_TEXTURE_2D, glGenTextures(1))

glPixelStorei(GL_UNPACK_ALIGNMENT,1)

glTexImage2D(GL_TEXTURE_2D, 0, 4, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE,img)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST)

glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST)

glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL)

def InitGL(self, width, height):

self.LoadTexture()

glEnable(GL_TEXTURE_2D)

glClearColor(1.0, 1.0, 1.0, 0.0)

glClearDepth(1.0)

glDepthFunc(GL_LESS)

glShadeModel(GL_SMOOTH)

#背面剔除，消隐

glEnable(GL_CULL_FACE)

glCullFace(GL_BACK)

glEnable(GL_POINT_SMOOTH)

glEnable(GL_LINE_SMOOTH)

glEnable(GL_POLYGON_SMOOTH)

glMatrixMode(GL_PROJECTION)

glHint(GL_POINT_SMOOTH_HINT,GL_NICEST)

glHint(GL_LINE_SMOOTH_HINT,GL_NICEST)

glHint(GL_POLYGON_SMOOTH_HINT,GL_FASTEST)

glLoadIdentity()

gluPerspective(45.0, float(width)/float(height), 0.1, 100.0)

glMatrixMode(GL_MODELVIEW)

def MainLoop(self):

glutMainLoop()

if __name__ == '__main__':

w = MyPyOpenGLTest()

w.MainLoop()

某时刻的运行效果如图：