pyglet 绘图原语 GL_POINT。缓冲区问题？

Question

pyglet 初学者。我在使用 pyglet.graphicss.draw() 绘制 GL_POINT 时遇到问题。我希望这个 GL_POINT 在下一个像素缓冲区上一个接一个地绘制，但似乎该函数没有保留最后一个 GL_POINT 在下一个像素缓冲区上绘制。

import pyglet
from pyglet.gl import *
from pyglet.window import key  # for key input, on_key_press

window = pyglet.window.Window(800, 600)  # create a window object with the resolution of 800x600
window.set_caption('window title')
glClear(GL_COLOR_BUFFER_BIT)
@window.event
def on_key_press(symbol, modifiers):  # keyboard input handler
    if symbol == key.L: # Drawing a center point
        print("DRAWING TEST A POINT (400, 300)")
        pyglet.graphics.draw(
            1, pyglet.gl.GL_POINTS,
            ('v2i', (400, 300))
        )

    elif symbol == key.K: # Drawing a bit further 100 more horizontally from center point
        print("DRAWING TEST A POINT (500, 300)")
        pyglet.graphics.draw(
            1, pyglet.gl.GL_POINTS,
            ('v2i', (500, 300))
        )

pyglet.app.run()

按 L 将绘制一个中心点。

然后按 K 将从中心点水平绘制 100，最后一个中心点消失。

错误在哪里？我的代码有问题吗？如果不，我的猜测是，pyglet.graphicss.draw() 函数实际上是一个接一个地重新绘制原始形状吗？我如何编写代码来绘制一个接一个？

Answer 1

问题是由 Double buffering. You can solve the issue by drawing the point to both buffers. Draw the point twice and swap the OpenGL front and back buffers in between by (flip).

引起的

pyglet.graphics.draw(
    1, pyglet.gl.GL_POINTS,
    ('v2i', (400, 300))
)
window.flip()
pyglet.graphics.draw(
    1, pyglet.gl.GL_POINTS,
    ('v2i', (400, 300))
)

但我建议将点添加到列表中并绘制列表。例如：

import pyglet
from pyglet.gl import *
from pyglet.window import key  # for key input, on_key_press

points = []

window = pyglet.window.Window(800, 600)  # create a window object with the resolution of 800x600
window.set_caption('window title')
glClear(GL_COLOR_BUFFER_BIT)
@window.event
def on_key_press(symbol, modifiers):  # keyboard input handler
    global points
    if symbol == key.L: # Drawing a center point
        print("DRAWING TEST A POINT (400, 300)")
        points += [400, 300]

    elif symbol == key.K: # Drawing a bit further 100 more horizontally from center point
        print("DRAWING TEST A POINT (500, 300)")
        points += [500, 300]

    pyglet.graphics.draw(len(points) // 2, pyglet.gl.GL_POINTS, ('v2i', points))

pyglet.app.run()

pyglet 绘图原语 GL_POINT。缓冲区问题？

pyglet drawing primitive GL_POINT. A buffer issue?

python

opengl

pyglet