Ok! I have made some progress. From the above example, the gaussian matrix is returning 0.5, 0.5 meaning the two line segments intersect both at half way, which is correct as you pointed out. So now I'm not sure what to do with these two values, and how to incorporate the z axis into this whole thing... (sigh) this is so difficult... How do I convert 0.5 and 0.5 into (-1, 0, 0)?