SubD investigations with tins of Goblin Enamel



  • At caisson's suggestion I started playing with subdivision surfaces for my tin of Goblin Enamel. I found this was rather interesting, so I'm posting it here on the off-chance that somebody else might too.

    I went back to square one and created a base mesh - an 8-sided cylinder closed at the bottom with 8 triangles, top left in the image. The bottom rim is very sharp, so I made additional meshes with bevels and control edges (the three below it on the left of the image). The second mesh (far left,second from top) has a bevel added. The third mesh (far left, second from bottom) uses a control edge either side of the bottom rim to guide Poser's smoothing. The fourth mesh (far left, bottom) has a bevel plus control edges either side of the bevel.

    (The coloured material zones simply let me easily see how the bevels and control edges/faces are affected by subd. For practical purposes the side and vertical control edges would be the label, the base and horizontal control edges would be the base, and the bevel would probably be part of the base too)

    The second column is the same meshes in PP2014 but with subdivision levels set to 1 for both preview and render.

    The third column was just a cack-handed way of checking whether SubD in DAZ Studio 4.8 behaves the same as PP2014s.

    The final three columns are a render of the first three columns. I also applied an image map with text to the side and control edge material zones to see if the subd distorted things.

    0_1475732832899_Tin_8_TEST1.jpg



  • Next I tried rendering with Smooth Polys enabled* to see who turns into an overinflated balloon!

    After looking at this image and the one in the provious post I think that I can rule out the base mesh (top row) and bevel-only version (second row).

    0_1475733459118_Tin_8_TEST1-pt2.jpg

    *I'm a bit of a displacement fiend, and I don't like the sharp edges created by angles above the crease angle limit. I also like my meshes as minimalist as possible. With Firefly and Smooth Polys I can do wonderful stupid and pointless things with displacement, e.g. my warpy cube. I think there might also be some sensible uses...



  • Just to clarify what I'm doing here - I'm not intending to use an 8 sided cylinder as the mesh for my tin. However, if I take an 8-sided cylinder and apply one level of subdivision that will give me a 16-sided cylinder. All I want is for this 16-sided cylinder to look correct when rendered regardless of the Smooth Polys render setting.

    The top row is no good because of the deformed profile.
    The second row (bevel only) has a slight profile deformation because the bevel is stretched upwards. I would probably have gone for this if I hadn't been let into the secret of control edges.
    The third and fourth rows both look good to me. Both of these give me a 16-sided cylinder that meets my render criteria. So I think I'll look at the once-subdivided versions of those two in a little more detail.

    Why 16-sided? I mentioned in my post over on the other thread that I thought 32 segments were the minimum necessary to make the tin look round. That's probably true for the close-up render I was doing, but for general background use 24, 16, or even less might suffice. Especially with the Smooth Polys and/or subd option in Poser itself to add some extra roundness if required.