fixed scaling in opengl

can anyone help me out in scaling of opengl. i am using the glScalef() function to scale polygons but what i want is that the scaling is done 开发者_如何学Con a fixed point but it is not achieved with the following function. can some one put some light on this?

Scaling generally happens around the origin. Therefore, to scale around a point (x,y,z), one must translate the origin, and back.

Specifically:

• translate by (-x, -y, -z)
• scale
• translate by (x, y, z)

Note: it is the very same thing as rotating around a point.