Hi! I have a model drawed by GL_LINE_STRIPs, so it looks like it's made of a net. I am trying to light it upp with a light behaving like a head light when I look on it with gluLookAt. The problem is that the net is black when I turn i 180 degrees. Is it not possible to light up a net drawed by GL_LINE_STRIP?

are you sure that you set the normals right?

Yes, you are right. I have not set up normals. The problem is that I have no normals. I am only given the points. I was hoping that I didn't need to... yeah stupid I know.

The thing is that I am working on an old program written by a scentist. This program takes pictures on verry small structures and visualize them with GL_LINE_STRIP to show this structure... plotted with glVertex. I have read about glEvalCoord and this would maybe make it possible to generate normals. But I am not convinced that this will generate the exact same structure as if using glVertex. And that is pretty important. Do any one know if they draws the same shape? That is, if using either glVertex and glEvalCoord...

you can calculate them. Take a look here