Making a solid polygon

I need to make a solid polygon that will not allow other polygons to pass through it. What would be the best solution? It will act as a wall in a way. And possibly be loaded into an array so a map may be created. This is for a game.

Thank you for your time.

OpenGL has nothing to do with how “solid” something is. It simply draws what you tell it to draw. If you want something to not pass through something else, then it is up to you to not tell OpenGL to draw it passing through that something else.

You need to use some form of collision detection, on the CPU, to see if something is trying to pass through it. Then, you need to move it away so that it isn’t colliding.