dx9 fixed function lighting system
i just noticed i'm getting specular reflection on the wrong side of tree trunks.
its most noticeable during night scenes, lit only by moonlight, a single directional white diffuse light of low intensity. due to the complexity of the lighting equation used, i opted to use almost no overall ambient, and use a single diffuse directional light for sunlight or moonlight. then i use materials to control the lighting of various things (plants, ground, rocks, etc). so a fair amount of time was spent tweaking the specular for the plant material, so moonlight would reflect off of leaves just right. but for some reason, it also does a specular reflection on the back side of tree trunks (which use the same material). this makes no sense. the triangles are backfacing to the directional light. or does the lighting not take backfacing into account? and it does specular whenever the angles are right, irregardless? and i have to create and use a non-specular tree trunk material to get rid of it?