ARB_fp & fragment-position


I’m trying to learn a bit more about fragment-programs, how would I go about getting fragment.position in worldspace coordinates?
I’m attempting to calculate the direction between the current fragment and a lightsource-position…

I suppose it would be better to do this per-vertex and interpolate the result across the polygon, but I just want to get something
simple up and running

Anyone care to help me out?


You just send them via some texturecoord set.