Breakdown - Stag Beetle (Prosopocoilus Occipitalis)

Hi everyone,

I have recently been working on a stag beetle, which is one of the most difficult pieces I’ve worked on so far. Through the course of this project I wanted to improve on modelling , which has always been my weakest suit and further push my Texturing and Lookdev skills and see how far I can take it. I also wanted to take a project, from a rough concept in my head and push for realism as far as I can.

Note: I was responsible for all aspects of this project. From preproduction, to every aspect of production to the final tweaks in post production.

The look of my hero shot is inspired by orionmystery’s photography

                                                                      Hero Shot

                                                                               Close up - 1

                                                                                      Close up -2

Summary

- General overview of the project (software, workflow, etc...)

- Gathering references and creating the idea for the shot

- Modeling (sculpt, retopo, UVs)

- Texturing (Displacement Sculpt, SSS Maps, General Diffuse, Mari)

- Lookdev (Renderman)

- Rendering  and Optimisation 

1. General Overview

For this project I used Maya for general modelling and UVs, this is the software I am most familiar and comfortable with, it is also the software I use the most in college so it does make sense to me.

Mari was used for texturing, I used to use mainly Affinity and Mudbox initially, but after our college got us Mari licenses . . . Well, I couldn’t help but make use of it to push the texturing process further

I’ve tried to make this asset as production ready as can be and iron out all the kinks I could see.

I will be working in ACES, as for me, it does simplify my workflow quite a bit. 

2. Gathering references

My first order of business was, as you already know. Gathering references. I went to as many beetle sites possible to create the most comprehensive reference board I could. The larger the reference board, the more I get to pull for my textures. I wanted to make sure I had every major section of the beetle covered in one reference or the other.

The following is my condensed Look and Mood Boards as well as a general reference board. 

                                                                                                 General References

                                                                                         Lookboard

                                                              Moodboard

As you can see in the bottom right of both images, after reference gathering I proceeded to sketch out digitally what I visualised my hero shot would look like.

Here is a more uncompressed version of my final sketch.

As you can already tell there are some stark differences between the final and my Lookboard but sketching this provided a strong drop off point and helped me Immensely to structure out my composition and established the composition elements that would be visible in the shot.

In hindsight, one of the things I would definitely change is the lighting. Here I have a soft light on the beetle with god rays, because well. I wanted soft light and god rays. As you know both those elements cannot coexist. Looking back now I would definitely make a more solid choice between one or the other. 

3. Sculpt, Retopology and UV’s

For this beetle, I started out with a turntable, which again I sketched digitally. These are all just preproduction elements that I did to simplify my workflow.

Note that I’ve also put in scale references as I wanted to make a production ready asset and having the correct scale from the get go really helps with the setting of physical parameters such as lighting and subsurface.

Following this I went into the blockout. This was a very rough stage and serves only to block in the base shapes so I will not be adding it here.

After this stage however I worked on the sculpt. The sculpting was done in Mudbox as it’s a software I’m quite comfortable with.

This stage was by far the most challenging for me as I’ve always found sculpting to be quite challenging. I’ve come back many more times to refine the shapes as and when needed but this is what I had ended up with at that point.

Following the base sculpt, I worked on the retopology of the asset. For this purpose I used quad draw in Maya to manually retopologize the sculpt.

For the UV Layout’s I used two UDIMS. Additionally I set my seams up primarily in interiors where they wouldn’t be visible not only in my shots but in a 360 as well. Such that this asset could be placed in any angle and the textures still hold.

The first tile holds a large chunk of the beetle. Primary parts such as the head, Torso and Upper and Lower back have been accommodated in this tile while the Legs, Sensors, Antlers and Small protrusions have been laid out in the second tile. The maps used for both tiles are 4096x4096.

4. Displacement Generation (Mudbox) and Texturing in Mari

After the retopology and UV’s were done I took the mesh back into Mudbox as the displacement and Normals extraction in this software is quite nice. For sculpting my normals and Displacement, I created custom Alphas in Affinity Photo. Primarily for patterned holes and the eyes and also mainly for the hole variations on the underbelly of the insect.

The snake skin and Phasor noise textures in the bottom right are for the Feet and Sensors respectively.

For the microbump that seems to be repeating all over the beetles body, it looked a lot similar to human goosebumps. So I just picked up an image of the same and applied it as a stencil over the beetle. After a bit of tweaks I achieved the result I was looking for. 

After sculpting out my Height and Normal maps I brought them into Maya to ensure everything was working correctly.

Excuse the overexposed footage. I really was trying to focus on the displacement and normals alone and didn’t pay much attention to the lighting in this stage.

Once the Normals and Displacement were done I moved on to focus on the Texturing. Like I said before the Texturing for this project was done in Mari.

Treatment of Textures

The very first step for me when it came to texturing was to

1. Get rid of specular highlights, hotspots and shadows : 

All of this was done in Affinity Photo since thats what I got to work with. It’s got a few flaws but is overall quite a nice software.

Take for example the head. This was the reference image of the head I had to work with

As is apparent, theres plenty of hotspots and plenty of highlights and shadows. In hindsight I would spend a bit more time looking for more neutrally lit elements. Then again, wheres the fun in that right?

Anyway, this is what my maps look like after removing the highlights, bringing up shadows and getting rid of hotspots.

The same process was then followed for every individual part of the beetle.

After this was done, I could finally take the project to Mari where I began my texturing process. For this process, as I was new to Mari I used Zak Boxalls workflow for Mari and implemented the same process for texturing my beetle.

2.Base Tileables : 

For texturing the beetle I started out initially with 4 Tileables, 2 for the upper body, 2 for the lower body and 1 for the eyes. These provided me with a sense of the base hue as well as served as a failsafe in case any holes were left in the texturing.

3. Diffuse Projection : 

The next step was to project my prepared images onto the beetle. For this step it was of utmost importance that the UV’s were cut properly. If not, the entire process would have been much much more tedious. Thankfully, I didn’t have too many issues in this stage (Phew) and was able to get by with relative ease.

Since I was using different images for different parts, it was important to make it look like it was all just one texture and not multiple images sewn together. Most of the hue matching was done in Mari

Just for reference, this is what my beetle looks like before and after color matching.

In order to break the flat look of my Diffuse and to add a bit of depth to the textures I started out with my imperfections. It’ll take too long to go through every imperfection layer so I’ll break them into general and more specific imperfections.

4. General Surface Imperfections: 

The first set of imperfections were general imperfections I found on the surface of the beetle in my reference. Most of these were done taking the midtones of my beetles and offsetting them with grunge maps. Then masking those with paint layers.

This is how my map looks like with and without these imperfections.

5.Surface specific imperfections: 

Once I was happy with these general imperfections, I added in imperfections which were more specific to the stag beetle. For this I pulled ideas from different reference images I had. These imperfections are ones that occur by virtue of the environments this beetle is a part of. 

These include, sort of pseudo stretch mark looking imperfections on the back

Diffuse fadeoff along the edges

Surface specific stains and skin damage along the lining of the torso.

Pigmentation along the inner wall of the torso

General imperfections around the frontal lobe

There’s a lot of other small details, but in a bid to keep this as brief (Slow nod) as I can, I’ll skip over it.

In order to add a bit more believability to this diffuse, especially along the serrations of the underbelly, Substance sampler was used for this purpose.

SSS Map

Finally, for the SSS maps. The stag beetle has a lot of really dark portions that almost clip to black. While their levels has been tweaked in Mari, the SSS Mean free path and general scattering would almost never be this dark. For this purpose, I created a surface specific scattering map.

This helped in really dark areas, namely the side of the head and especially in the sensory area of the face.

This section really scatters a lot of red in my reference and creating a surface specific map really helped me with the SSS in the lookdev stage.

SSS Mask

Secondly, I created an SSS Mask. As in the real world, SSS and Diffuse are inverses of each other. I thought it would then make sense to have specific maps to tell renderman where to add in my albedo and where I should have my SSS map work. This is what my final SSS mask looked like.

Roughness     

Last but certainly not the least is the roughness map.For this I used the AO map from mudbox in tandem with my diffuse. After using levels to deal with the extreme blacks and whites and bringing in a base mid grey reference.

This is what the final map looks like.

5. Lookdev (Renderman)

For me personally, a 3 point light setup didnt let me lookdev correctly. Due to the sheer amount of protrusions and the irregular shape of the beetle, I had to add lights where the texture was getting crushed, and highlights in certain portions I knew had texture in order to lookdev correctly.

This is what my final lookdev turn looked like

After that the supplementary composition elements like the mushrooms, Branch, Rocks, Soil, Bark and Flowers were quickly textured in Mari. I quite like how the flowers turned out

6. Rendering and Optimization

After tweaking my render settings, I settled with Min samples of 8, Max 512 and a pixel variance of 0.015. These parameters seemed to be giving me the best results!