# Re: Draw a circle in OpenGL

Barry Fishman wrote:
Elvis Nguyen <nvntung@xxxxxxxxx> writes:
Somebody test the snippets code below

(require '#:asdf)

(glfw:do-window ("A Circle Example")
((gl:with-setup-projection
(glu:perspective 45 4/3 0.1 50)))
(gl:clear gl:+color-buffer-bit+)
(gl:translate-f 0 0 -5)

(draw-circle 100))

(gl:with-begin gl:+line-strip+
(dotimes (i 360)

My purpose is to draw a circle using cl-glfw. The rusult is nothing. I
have tested many times.

You are trying to look at a 100 unit radius circle from 5 units away.
You need to draw a smaller circle "(draw-circle 1)", or look at it from
further away like:

(gl:translate-f 0 0 -500)

and move the perspective clipping plane further out so it doesn't
get clipped out of the picture in the process.

Or set a camera angle very close to, equaling, or exceeding 180 degrees. :)
.

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