Hi, my name is Jonas Skoog and I work as Lead Character Artist at Goodbye Kansas Studios. 

In this article I will share my workflow of taking a VFace package and transforming it into a fictional character.

During the years TexturingXYZ have continuously released new ways of utilizing the surface maps they provide and find ways to make the workflow faster.

With the new VFace Package everything is now connected to actual geometries accompanied by calibrated lighting and matching references to give the best possible means to understand and recreate the surface qualities of the subjects.

This is my approach and only one of many possible ways of using VFace but I hope some of you might find it useful!

Initial VFace setup and Shading

Having all the building blocks already aligned in the VFace pack makes the initial setup  really fast. 

In the package you have all the components needed to set up a quick lookdev scene such as:

• Head Topology/UVs from Scan along with eyes, lashes and brows.

• Calibrated Displacement along with the same Multi Channel Displacement we are used to seeing from TexturingXYZ.

• Albedo, RGB masks and Utility maps such as Cavity and Hemoglobin.

• Calibrated HDRIs with Lighting references and MacBeth Charts.

Having good light references matching the HDRI helps a lot when trying to get the SSS and Speculars accurate in your lookdev!

To kick it off I started by assembling all the pieces of the Package in Houdini where I do my Lookdev using Vray. For the skin I use AlSurface and plug in all the VFace maps without any modifications. The lashes and brows are also imported straight from the package using a Vray Hair Shader. With all the maps plugged in it was time to try out the lighting! In order to get an accurate lighting towards the Reference in the Package there are a few things to consider. First is getting the light direction to match obviously and is easily done by adding the HDRI to a Vray Dome Light and rotating it into place at render time. Second part is using correct colorspace for your texture. In this case all HDRIs are saved in  Linear sRGB so make sure to use  Utility-Linear-sRGB as your colorspace input as well as a correct output, in my case ACES-ACEScg since this is the colorspace I'm rendering in. Final step is correct intensity. To get this right you need to calibrate your Dome Light against a MacBeth chart in your render and increase the intensity to match gray value in the Reference Chart provided.

To get faster control over the Speculars I have set up all the RGB masks from the package with controls using a Layered Texture node in Houdini. 

This way I can dial everything directly in Vray framebuffer IPR which makes it faster to iterate.

I use the same setup for both Specular Lobes as well as the Micro displacement to control the breakup individually in the same facial zones. 

A more in-depth guide on how to set this up is found in the VFace Documentation for those interested.

Wrap

When I was happy with the shading it was time to transfer everything to my own topology (You can of course use the Topology provided as well and skip this entirely).

For all geometry wrapping I use Wrap3.  Not really much to say about it since there are heaps of tutorials on how it works out there.

To get a clean transfer I made use of the fact that VFace comes with two geometries for the head. Both open and closed eyes. 

I blended them middle way to get rid of any creases/overhang on the upper eyelids and also opened the mouth to avoid lip intersections then baking.

Texture Transfer Houdini

When I had a good wrap in place I took both heads into Houdini to do the texture transfer. This time I used the Maps Baker in Game Dev Toolset for Houdini.  

This toolset have lots of good stuff and the Baker itself is really easy to use. Just plug in two meshes and a Quickmaterial holding your texture and you are ready to transfer:

https://www.sidefx.com/tutorials/game-development-toolset-overview/

With the baked texture I hardly did any post work except adding in the scar I did in the sculpt and emphasizing some features in the model. The Albedo textures comes crosspolarized and unlit from any Occlusion with all head/facial hair already removed. Adding  your  Float and/or MultiDisp ontop of your Albedo is by the way a simple way of adding personalized details and pushing it further. In this case I set the Float Displacement to Overlay to get the red tint of the scar I was after.

Sculpting

I had wanted to  create Kenpachi for a while being a Bleech fan. 

He has a few different looks during the Anime and Manga to choose from but I settled with the classic "spiky hair and gold trim on eye-patch" since I feel this is one of his most interesting looks.

Since most details already live in the MultiChannel Displacement I focus mainly on bigger shapes while having the Displacement as a temp layer in zbrush to guide fold directions etc. 

I tried to stay relatively realistic with this model and not go too much overboard even though Kenpachi has some crazy face proportions in the anime that I love.

The Zbrush layer with the XYZ DSP map applied is just for visualization while sculpting the bigger shapes. Having it in mesh is less heavy as well. Once happy with the sculpt, I remove the XYZ DSP layer.

Lighting

For this piece I wanted to try a creative lighting scenario based on this photo I found online  (unfortunately I cant find the photographer but would love to credit if someone knows the name).  I really like the mood of this image with the burning Snoot across the eye and thought this would work well with my piece, bringing attention to his non-covered eye. The image also reminded me of a classic 90s Anime called Ninja Scroll with the blue tinted background that I wanted to incorporate in my piece.

I had never attempted a lighting like this before so thought it would be a fun exercise. 

Matching the overall light direction from my reference was quite easy since you clearly see how the shadows fall on the face, creating that Rembrandt look.

The light streak over the eye took some more trial and error to get right. I started by trying to find the right direction and sharpness for the snoot effect. I ended up using an Area light with high directionality and a mapped B/W texture with a steak cut-out done in Photoshop.

To bring forward Kenpachi from the background I used a small light directed towards the wall behind him. I also intentionally let that light spill slightly on the side of the face to bring some more interest to the shadow side even though it was not present in the reference. 

The last light I used was just a small area to bring some life into the eye since the snoot was angled too high to get caught in the eye reflection.

Groom

For Grooming I use Houdini as well. I really love its node based Hair System which give you endless possiblilities when it comes to creating all sorts of hair. Since everything is node based you get a robust, non-destructive setup and depending on your coding skills you can use Vex Expressions to customize it to anything you want. When it comes to creating Guide Curves I actually use a 3rd Party Plugin called GroomBear which I find much easier to work with than Houdinis native tools. https://kwac.gumroad.com/l/groombear

Thanks for reading through this article, hope you have found it interesting and now have an understanding of what VFace contains and how it can be used in your project.

Best, Jonas Skoog