glfwSwapBuffers 的时间模型

Question

This function sets the swap interval for the current context, i.e. the number of screen updates to wait before swapping the buffers of a window and returning from glfwSwapBuffers. This is sometimes called 'vertical synchronization', 'vertical retrace synchronization' or 'vsync'.

这是否意味着

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 Generate next frame
 Wait until next frame is available
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即循环周期与计算任务无关或

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 Generate next frame
 Wait for 1/refresh_rate time units
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也就是说，延迟被添加为执行循环的额外时间。

Answer 1

第一个是正确的。没有固定大小的延迟。