Smooth mirroring?

I am trying to model a sheet of metal uncurling from a rolled up position. I’ve gotten the metal to act more or less like I wanted, but I can’t seem to get the mirroring right. I’m using raytracing mirroring, but when I render it, the mirroring appears different in EVERY FRAME. On playback of the finished animation, the mirroring is jumping all over the place. Does anyone know how to fix that?

Video (MPEG-4, 130KB)

.blend file (222KB)

you don’t actually have mirroring enabled on that object

you have the ray mirror button pressed but the RayMir is set to 0. You also need to hit the ray button in the render window. turn osa down for your test renders.

hope that helps!

Okay, I fixed that. But I’ve still got a problem with the mirrored streaks jumping all over the place instead of smoothly rolling across the sheet like they would on a real piece of metal. It’s the same as on the first one, only now the reflections are jumping instead of the shaded streaks. I’ve updated the files linked above to reflect the changes (no pun intended) so you can see what I’m talking about.

try turning subsurf on for your object. I think that will fix it.(F9 Mesh Panel)

Well, subsurf fixes that problem… but distorts the sheet. Now instead of a discreet sheet of metal, it’s kinda oblong and too thin at the edges. I tried reducing it to zero subdivisions, but then the original problem returns. Any other ideas, or am I stuck with that?

well, read my sig!

lol, you can do anything.

to fix that I would select all the edge vertices and hit shift-E. That will allow you to control the crease applied to each edge.

i don’t mind anwering these questions but I suggest you go through some tutorials and read the manual. You can get to these things and more right from blenders help menu.


Well, I didn’t think of that because I think it wasn’t even present in 2.33, which was the last version I had used extensively. Unfortunately, when I creased it, the problem came back AGAIN, even though it’s got subsurf on. However, I began to suspect that it was more a problem with computing reflections off of perfectly cylindrical surfaces in motion, so I tried re-doing the subsurf and creasing it to 0.992, which is only just barely subsurfed at all (hardly even noticable if you do it right), and lo and behold, it works.

Thanks a million for the help, I’d have never have thought of trying that myself.

you can also try doing just one side at a time with Shift E, that way you don’t effect the edges that are running along the main face.

glad i could help.

Yeah, that’s exactly what I did. I selected only the edge chains that needed to be sharp, and did so one at a time so as not to disturb the main sheet face. Thanks again!