Lighting problem after drawing a cylinder
I've just started learning openGL and have a doubt that is intriguing me (I searched and read but couldn't find an answer).
So, I created a cylinder (out of triangles), uploaded the points to a VBO and it looks fine. The problem is, when I add lighting to the scene, the top circumference looks strange. It looks like this: Cylinder top
I believe I have calculated the vertices and normals correctly, and can't figure out what's wrong. Instead of a 'smooth' surface, I'm getting all those triangular shades. Is there an obvious reason for this to happen?
If useful or necessary, I'll post code. Just wanted to start by knowing if there is a quick answer to the problem :)
Thanks in advance!