Lines appear interrupted

Does anybody know why lines located on quads cannot be seen good? They appear interrupted. I’ve already tried messing around with glPolygonOffset to no advance, as well as to put the lines a bit towards the viewer.

Get the source code here .
View what is the problem in the picture over here .

Note : you need Visual C++ to compile the code.

[This message has been edited by Simon666 (edited 12-02-2002).]

This is just a wild guess but - since the effect only seems to occur at the ‘wall’ - could it be, that the line drawing algorithm steps ‘behind’ the wall and is clipped?
Did you try to omit the wall to see if the lines were complete then?

Nick

I omitted the quads for the bars in the graph and then all lines appeared as they should.