问题 I was watching a video about pyglet and I tried to create a triangle: import pyglet from pyglet.gl import * class mywindow(pyglet.window.Window): def __init__(self, *args,**kwargs): super().__init__(*args,**kwargs) self.set_minimum_size(300,300) window = mywindow(300,300,"deneme", True) def on_draw(): glBegin(GL_TRIANGLE) glColor3b(255,0,0) glVertex2f(-1,0) glColor3b(0,255,0) glVertex2f(1,0) glColor3b(0,0,255) glVertex2f(0,1) window.on_draw() pyglet.app.run() when I run this code; I get this