How do I set the line width in OpenGL relative to the viewing area of a frame buffer?

glLineWidth rasterises the width so it shows as that width on the screen. I want it to be tha开发者_如何学Got width on a frame buffer.

Thank you.

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Basically, your screen width is a different size from your frame buffer?

desired_size = size_on_screen * (frame_buffer_width / screen_width)