Pyglet VBOs glVertexPointer

Question

I've used PyOpenGL for a long time, but now, I've switched to PyGlet. PyGlet is more strict the PyOpenGL, so I'm now learning it. I've written a simple code using VBOs to render a triangle(I've took the base from a PyGlet tutorial), but it doesn't works for me.

It shoud render a colored triangle, but instead of, It renders a white triangle. What I does wrong?

Here's my code:

from pyglet.gl import *

window = pyglet.window.Window()
glEnableClientState(GL_VERTEX_ARRAY)
vertices = [
    0,0,0,
    window.width,0,0,
    window.width,window.height,0]

colors=[1.0,0.0,0.0,
        0.0,1.0,0.0,
        0.0,0.0,1.0]

class VBO():
    def __init__(self):
        self.buffer=(GLuint)(0)
        glGenBuffers(1,self.buffer)
    def data(self,data):
        data_gl= (GLfloat * len(data))(*data)
        glBindBuffer(GL_ARRAY_BUFFER_ARB, self.buffer)
        glBufferData(GL_ARRAY_BUFFER_ARB, len(data)*4,
                    data_gl, GL_STATIC_DRAW)

    def bind(self):
        glBindBuffer(GL_ARRAY_BUFFER_ARB, self.buffer)
    def vertex(self):
        self.bind()
        glVertexPointer(3, GL_FLOAT, 0, 0)
    def color(self):
        self.bind()
        glColorPointer(3, GL_FLOAT, 0, 0) 




vbo=VBO()
vbo.data(vertices)
color=VBO()
color.data(colors)

@window.event
def on_draw():
    glClear(GL_COLOR_BUFFER_BIT)
    glLoadIdentity()
    vbo.vertex()
    color.color()
    glDrawArrays(GL_TRIANGLES, 0, len(vertices) // 2)

@window.event
def on_resize(width, height):
    glViewport(0, 0, width, height)
    glMatrixMode(gl.GL_PROJECTION)
    glLoadIdentity()
    glOrtho(0, width, 0, height, -1, 1)
    glMatrixMode(gl.GL_MODELVIEW)

pyglet.app.run()

Thanks in advance!

Answer 1

我可以通过添加以下内容来显示颜色：

...

glClientStateEnable(GL_COLOR_ARRAY) 

vbo=VBO()
vbo.data(vertices)
color=VBO()
color.data(colors)

...

pyglet的嵌入式文档非常缺乏帮助，但glColorPointer的手册页非常清楚地指出glDrawArray忽略了颜色数组，直到通过glClientStateEnable启用了GL_COLOR_ARRAY。