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I'm having some problems with transparency/raytracing/backface culling. First, if I have a paint effect, let's say, on a NURBS surface, it won't render behind a transparent blinn mat'l unless antialiasing is set to a low setting (i think medium is the highest I can go while still keeping it visible). i think it's not rendering in front of the transparent material- said material is surrounded by a fully opaque blinn shader and the paint effect can't be seen. (more precisely - this is a problem with the tutorial on the Alias learning tools that's based on the short movie blue, the lesson where you build the space station and the paint effect is for the stars outside. the room has a window, and outside you can see planet earth and the stars are painted on a large-scale nurbs sphere) i've read some of the forums and there's talk about depth buffers and scanline but I don't really follow. the second is: can post effects (like glow) show up in raytraced reflections? obviously not since the raytrace happens during rendering. how do you manage that special effect? just staying away from it? i wouldn't know how to add this even using compositing. third question: I built a room, so I made a polygon cube and reversed its normals. then I turned off component display of back faces so i could see in the room. when i switch to "high quality rendering" in the viewport shading tab, the block goes solid again - regardless of the setting in component display. so i went to the cube's shape node and in its attributes I switched it to "single sided" - so now the only face normals pointing in to the room are the ones that are renderable right? the camera being outside now renders perfectly in the software renderer. so now if I bring my camera into the room, the floor doesn't render, but the walls do. then at different camera angles the floor might render, but only half of the triangle (it's not tessellated, just one segment on each dimension). I guess this is a complicated question in the sense that I can't explain myself... so basically the question is: how do I force maya to render only the faces that have the normal on the side of the face the camera sees, regardless of how many other faces are in the way? here's my ascii orthogonal art. legend: -> ...normal | ...poly face o-> OR o-* ...persp. camera eye and look-at this arrangement works, but I don't want to be limited to having my eye outside of the flipped-normals room. --------------- o-> | | | | |-> ^ <-| | | | --------------- this one does - note the camera is low, pointing slightly down: --------------- | | | | |-> ^ <-| | o-> | | --------------- this one doesn't work (floor won't render at all, or only one of the triangles of the floor polygon. i've used an asterisk for the camera look at since i can't find a suitable character in this character set, and i'm a bit lazy for it right now.) - note the camera is high, pointing mostly down, but slightly to the right of the ASCII scene): --------------- | o | | | | |-> ^ *<-| | | | --------------- it seems the triangles on the floor render depending on the angle of attack of the camera? a shallow angle will render fine but anything more acute (>45degrees?) will show through. yet the wall on the right always renders fine! it's had some extrusion done on it. more specifically, an inset followed by a slight push extrusion, to make a window ledge and a face for the window itself. I've used the commmand edit poly->normals->reverse to reverse all the normals in the cube. when I go to the normal node attributes there's several different normal manipulations, and the help file doesn't help a lot. is the component display setting considered at render time or is it just a viewport thing? should I keep the polygons double sided when I build them? What's the point of a normal if it's double sided, wouldn't there be two normals to a face, both opposite? I often feel the help file for Maya is very high level for me. if it's not in the tutorial book chances are I won't pick it up. the help is excellent for features I'm familiar with and just want to learn more deeply though. I'm sorry if I can't explain myself any better, I've spent a lot of time rereading and rewriting this question. Thank you for your effort and time.