Forum: Poser - OFFICIAL


Subject: surface imperfection material shader

iikuuk opened this issue on Jun 06, 2005 ยท 21 posts


iikuuk posted Mon, 06 June 2005 at 2:40 AM

Hi I was about to make it perfect, but now i see i need some help with a shader node. I was trying to do a surface imperfection node, which is somehow shows areas on the object's geometry where its bends(convex) more then 'normal'. The problems i found: - you cannot use du dv nodes (bugreport already sent) in P6 - dPdv and dPdu nodes show only the direction where the geometry tends, but nothing about if it changes. - dNdu and dNdv nodes contain the information we need, but since these dont change inside one vertex, you get only semi results, which should be fed into a further shader (i.e. dNdu and dNdv will be the same in one vertex). I would be interested if anyone can show me a nice way to 'smudge'/blur any result in a P6 shader... (see attached shader node) From the shader: The way it works is pretty easy, it adds the length of the partial differentials of the normal vector, then transfers the values into a 0-1 interval. Last it checks if thats over a predefinied value. Although im a mathematician (kinf of), i didnt look too much for the correct equation, but if you have some advice, im defenitly curious.