B is for Ben: 3D model retopology / by Rok Andic

Retopology is one of those things that outside of rigging and modeling nobody wants to hear about. It is however essential to good puppet deformation. It is one of those things that I constantly try to evolve from character to character. I do not know whether this is from the ever evolving technology or simply because I like to constantly try new things. For Ben I decided to go with the simple idea of “better safe than sorry” and added extra edges wherever I had problems in the past. This also means that I’ll have to deal with those edges even if they are unnecessary.

In the past I would create only as much spans as I thought I would need. The reasons being simple. Capturing (or “binding”, depending on the software you use) is much easier with less topological data and animation playback is faster which is essential when the puppet is animated. This is great if you nail just the right amount of edge spans you need, but if you don’t and you need extra edges you are in trouble. Adding those extra details later is time consuming to say the least.

The face

The face is the most important because it carries so much deformation. I spend most of the time for retopology on the face. The areas I spend most time on are always those which deform most. In this case the eyes and the mouth.

I start by dividing the character into specific zones and layout each one separately. The zones being: eyes, lips, nose, cheeks, brows. I make sure each zone works well before merging and overlapping with the neighbouring zones.

For the eyes I divided it into 9 spans and for the mouth 13 spans. This should be enough to carry all the deformation I have in mind for this character. In the past I tried with less and blend shapes are faster to create but for some specific expressions I found it tricky to support extreme shapes with less spans. As I wrote “better safe than sorry”. Also if this character would perform a lot of close up acting shots I would probably add a few extra spans.

The body

The body can be tricky, especially in the shoulder and hip area. I don’t mind adding a few extra spans here. The shoulder always needs a lot of corrective deformations and it is just better to have some extra spans “just in case” to hold the shape. The same is with fingers. Especially the thumb area. Added extra spans this time.

Rigid elements

Helmet, jetpack and front button panel are mostly rigid objects which will not deform as much as the rest of the body. For this reason I kept the number of edges on the lower side.

Next steps

This model is now going back to Zbrush to create displacement maps and final details.