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copied!<p>You don't need to call <code>glBufferData</code> every single time in update - create and fill the VBO once (see <code>setup_initial_points</code>) and only update it with <code>glBufferSubData</code>. In case you are only working with a single VBO, you can also comment out the <code>glBindBuffer</code> call in <code>update()</code> (see code below). <code>GL_DYNAMIC_DRAW</code> vs <code>GL_STATIC_DRAW</code> won't make a big difference in this example since you are pushing very few data onto the GPU.</p> <pre><code>import pyglet from pyglet.gl import * from ctypes import pointer, sizeof window = pyglet.window.Window(width=800, height=800) ''' update function ''' c = 0 def update(dt): global c c+=1 data = calc_point(c) # if there's only on VBO, you can comment out the 'glBindBuffer' call glBindBuffer(GL_ARRAY_BUFFER, vbo_id) glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(data), data) pyglet.clock.schedule(update) ''' draw function ''' @window.event def on_draw(): glClear(GL_COLOR_BUFFER_BIT) glColor3f(0, 0, 0) glVertexPointer(2, GL_FLOAT, 0, 0) glDrawArrays(GL_POINTS, 0, 2) ''' calculate coordinates given counter 'c' ''' def calc_point(c): data = (GLfloat*4)(*[500+c, 100+c, 300+c, 200+c]) return data ''' setup points ''' def setup_initial_points(c): vbo_id = GLuint() glGenBuffers(1, pointer(vbo_id)) data = calc_point(c) glBindBuffer(GL_ARRAY_BUFFER, vbo_id) glBufferData(GL_ARRAY_BUFFER, sizeof(data), 0, GL_DYNAMIC_DRAW) return vbo_id ############################################ vbo_id = setup_initial_points(c) glClearColor(0.2, 0.4, 0.5, 1.0) glEnableClientState(GL_VERTEX_ARRAY) glPointSize(10) pyglet.app.run() </code></pre>

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