Tuesday 12 July 2016

Realistic Human Head in Zbrush and Maya

It's one of those CG cliches, model a realistic human head. So of course I had to have a go at some point. I got that chance last year when I had time and while I was getting more into ZBrush.

So to start with I laid out the the polygon loops over the reference image in Photoshop first to plan out my build -

The image ref was some old free human reference from the awesome site www.3d.sk

I did the initial modeling in Maya to create a base mesh.

I then brought the model into ZBrush and began adjusting some forms, some aspects of the head shape, enlarged and brought out the ears a little more and added some asymmetry.

Once I was happy with the forms at this point I went back to Maya to create the UV's (created in a 2:1 ratio to get maximum pixel detail). I then brought it back to ZBrush to continue detail modeling, mainly with alphas to create the small wrinkle and pore detail. Once I had that finalised I created my displacement and normal maps. There was not so much exagerated modeling (overlapping geo) that required a vector displacement so went with the standard height map.

I baked out at 8 x 4k and then did some cleanup on those maps in Photoshop. I've since found out that MudBox does a great job on displacement and normal baking (smoother result with better results at UV seams) so will probably go back to it at some point to create cleaner maps, but they were perfectly fine as is.

I then started the polypaint process. The model's highest subdiv level was 7 and at that level has a point count of 7.2 million, which is plenty to get some good detail into the texturing. I started with the overall colour tones and then started to bring in subtle vein and wrinkle detail along with freckles and other skin blemishes always keeping reference close at hand.

PolyPaint wip

Wire Diffuse and Spec Maps

Once I was happy I converted the polypaint to texture and then did my final tweaks in Photoshop and also created a spec map from that diffuse map (which was adjusted later as I went through the shading process). I also created a colour map for each sub dermal layer for the sss shader.

So then the base model was brought back to Maya for shading and lighting. I also created an eyeball at this stage with associated maps. I used mental ray shaders, the fast skin for the most part, just using a mia material x for the eye lenses. For lighting I used an IBL dome with an HDRI attached along with two area spotlights (area light settings in the mental ray tab of those lights along with a custom light shader node for shape of the light source though a ramp node)

So next is the hair which is currently a work in progress. I have created the eyelashes and for the hair I think I'm going to use a Fibermesh workflow and bring back to Maya and use the standard Maya paintfx hair. Why not use XGen you ask? Well I have already dabbled with it and it's great for the initial groom but with mental ray the quality of the shader just isn't great. I think I can get a better look with paint fx. But I'll see, maybe they'll improve the mental ray hair shader to match Arnolds one at some point. 

So hope you enjoyed this short overview of my head model, I'll post the hairy head when it's done.

Wednesday 9 March 2016

Classical ZBrush Sculpt

This is my first proper human anatomy study done in ZBrush. It s based on the Discolobus of Myron - https://en.wikipedia.org/wiki/Discobolus - my particular version is closely modeled on a version of the Townley discolobus at the British musuem.
It was created in ZBrush from scratch using ZSpheres as a base. When the sculpting was finished I exported mid sub div level meshes from ZBrush and re-topologised in Maya using quad draw. I then UV unwrapped the retopologised meshes and imported back to ZBrush for projecting the detail. I then baked out displacement, normal and various masking maps.

Texturing was done with a combination of Photoshop and Mudbox, Mudbox was great for painting out seams. Actually in the end I used mudbox for baking the final displacement and normal maps ( so much better than zbrush for that - no seams etc).
I then shaded and rendered the model in Maya using mental ray. Hope ya like.

Final ZBrush sculpt

Timelapse of ZBrush build

Re-topologised mesh in Maya

Final textured and shaded render in Maya

Final textured and shaded render in Maya

Final textured and shaded render in Maya

Tuesday 12 January 2016

CG Water FX

I've always been messing about with water stuff in my cg work, so I'm just posting a few vids here with some examples of that. Click on the images below that will link to the videos on vimeo

This is a short underwater sequence I created in Maya. I used the hot ocean deformer for the mesh waves and created a camera with motion to simulate floating. Then added a mia material with water preset and tweaked some of the values. Also added a simple fog for depth. Then comped in After Effects adding particles, DOF, motion blur, light shafts and grain and finally sound.

Created this simple setup to test a water shader and fake caustics. The caustics is a tileable and loopable image sequence created with caustics generator (can create 512x512 sequences free). The water is a mia material with a ocean displacement in the shader group. Did some After Effects jiggery pokery to add some umph.

Created this a couple of years back. Wanted to look at using particle flow in 3DS Max to create a swarm and decided to use fish. Then got carried away and went further with it. The fish is a free turbosquid model. I adjusted the model slightly for animation purposes and also adjusted the texture. All rendered in mental ray and then comped in After Effects to add the light shafts, motion blur etc