如何使用OpenGL绘制线形？

Question

我是python和OpenGL的初学者，我试图绘制带线的立方体。这是我的代码。它只是给我一个白色框架，里面没有任何东西。什么都没发生。我在这里做错了什么？调用函数的顺序是否有问题，或者投影有问题？任何帮助，将不胜感激。

def myInit():
    glClearColor(0.0, 0.0, 0.0, 1.0) 
    glColor3f(0.2, 0.5, 0.4)
    gluPerspective(45, 1.33, 0.1, 50.0)


vertices= (
    (100, -100, -100),
    (100, 100, -100),
    (-100, 100, -100),
    (-100, -100, -100),
    (100, -100, 100),
    (100, 100, 100),
    (-100, -100, 100),
    (-100, 100, 100)
    )

edges = (
    (0,1),
    (0,3),
    (0,4),
    (2,1),
    (2,3),
    (2,7),
    (6,3),
    (6,4),
    (6,7),
    (5,1),
    (5,4),
    (5,7)
    )


def Display():
    glBegin(GL_LINES)
    for edge in edges:
        for vertex in edge:
            glVertex3fv(vertices[vertex])
    glEnd()

glutInit()
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB)   
glutInitWindowSize(800, 600)  
myInit()
glutDisplayFunc(Display) 
glutMainLoop()

Answer 1

例如，设置远投影为1000.0的透视投影矩阵gluPerspective。投影矩阵旨在设置为当前投影矩阵（gluPerspective）。参见GL_PROJECTION：

glMatrixMode

用glMatrixMode清除每帧的显示：

glMatrixMode(GL_PROJECTION)
glLoadIdentity()
gluPerspective(45, 1.33, 0.1, 1000.0) 


Translate ([`glTranslate`](https://www.khronos.org/registry/OpenGL-Refpages/gl2.1/xhtml/glTranslate.xml)) the model along the negative z axis, in between the near plane (0.1) and far (plane). The model or view matrix has to be set to the current model view matrix (`GL_MODELVIEW`):

```py
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()
glTranslate(0, 0, -500)

用glClear交换当前双缓冲窗口的缓冲区，并通过调用glClear连续更新显示。

def Display():
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)

    # [...]

请参见示例：

glutSwapBuffers
glutPostRedisplay