Texturing Realistic Skin for Characters
My name is Tom Newbury and I live and work in Melbourne, Australia at the feature film company, Luma pictures. I have been working in feature films for the past four years. My role at Luma pictures is asset artist where I am expected to model, sculpt, texture and look develop assets for films. This can include props, environments and characters.
In this tutorial I will be going over my textural process when trying to achieve realistic skin for characters. This is the same process that I would use in production on a feature film. A big part of this process is using the textural resources from the website, Texturingxyz. This website provides both high quality diffuse and displacement maps which are perfect for the creation of realistic skin. When it comes to texturing realistic assets, I find it is very important to use textures as close as possible to the real thing. This is why I use Texturingxyz, the amount of detail and resolution in these maps are more complex than anything you could paint manually.
If you would like a more in depth guide of this tutorial, you can head over to my gumroad account where you can buy this tutorial in video format, along with a bunch of other tutorials on different subjects. This particular tutorial has over 6 hours of footage, all at realtime speed with no jump cuts or time-lapse. There is also a second tutorial in the realistic skin series which looks at my entire process of look development. This is the process of bringing all of the texture maps you have created and building them into a shader network so you can apply it to your model and then light and render to give you the final result. You can find my gumroad account through this link: https://gumroad.com/tomnewbury
Chapter 01: Texturingxyz
Texturingxyz is a big part of my realistic skin process. The two texture packs you need to achieve a realistic result is diffuse and displacement. To keep this tutorial from being too long I am only going to go over my process of creating the diffuse texture pass. You will find the entire process in my gumroad tutorial. When choosing the diffuse pack, it is helpful to buy one which reflects the gender and age of the character you are creating. Have a good look at the surface details to make sure the skin surface works for you. In my case I wanted an older male, with slightly weathered skin.
Chapter 02: Preparing Mari
Now we can jump into Mari. To start a new project start by clicking the ‘New’ button at the bottom left of screen and then import the asset you wish to project on. Once the scene has loaded you want to create your first channel. You can do this by right clicking in the ‘Channel’ pallet window. I name this channel, ‘work_channel_diff’. This is where I will be doing all of my diffuse texture work. Depending on how high rez you want your textures to be will determine how large you make this channel. I am going for a high level of detail so I am setting my channel to 8192x8192.
Chapter 03: Importing textures
Next you will need to import your textures into the image manager. To do this you need to open your ‘Image Manager’ pallet window. Click the import button at the bottom left of the pallet and navigate to the diffuse textures. When it comes to Texturingxyz diffuse maps, I find using the albedo maps to give the best results. Albedo is another word for diffuse maps which have had both shadows and highlights removed.
Chapter 04: Mari Tips
In my gumroad tutorial I have a whole chapter where I give an introduction to Mari and all of the tools I use. Here I will just go over my four primary pallets. The Channel Pallet is used to group your layers under different channels, such as diffuse, displacement, etc. The Layer Pallet is very similar to Photoshop layers, you can view the layers of your selected channel. The Image Manager is where you can store all of your textures and Projection is where I control the ability to project on top or through the mesh as well as a bunch of useful masking options.
Chapter 05: Diffuse First Pass
Now we can begin projecting the photos on the surface of our model, (this process can also be done in Mudbox). I start out by getting an overall coverage of the diffuse across the surface, not being too worried about messy stretched areas because these will be cleaned up through the process. The only areas which I won’t worry about at this point is the scalp because we don’t want to project the hair, and the ears because these are a complex area to texture.
Chapter 06: Diffuse Scalp
When it comes to texturing the scalp, the texture maps are not very helpful. This is because the model has hair in the way. To counter this, I grab the photo of the model with his head down and take it into photoshop so I can grab a swatch from his forehead and reproduce it into a tileable texture which I can then easily apply to my model in Mari. As a sample to my gumroad tutorial I have put this chapter on my Youtube account for free so you can follow along with it there: https://www.youtube.com/watch?v=4pjSU-MWNCQ
Chapter 07: Applying a Tileable texture
Once you have prepared your tileable texture you can import it into Mari using the ‘Image Manager’. Then you navigate to the tileable tool in the ‘Layer Palette’, (see image). This will create a layer with tileable functionality. You then drag and drop the tileable texture into the swatch and adjust the scale until it matches the rest of the skin detail. Right click the tile layer and click, create mask > hidden. This will create a mask icon on the layer but will also hide the tileable texture in the viewport. While selecting the mask icon you can use a soft brush with a white colour to paint on the scalp and reveal the tileable texture where it is needed.
Chapter 08: Texture the Ear 01
The ear is the most complex area to texture. This is due to all of the complex folds and overlapping areas. Because we are using the albedo diffuse textures it gives us a very clean texture for the ear. I make sure to switch my projection type from ‘front’ to ‘through’ in the ‘projection’ pallet window. This allows me to project through the folds of the ear, this will make the process much faster.
Chapter 09: Texture the Ear 02
Once I have projected the ear as close as I can I then use the ‘lattice’ tool to stretch and squash the texture to match my stylised ear as best I can. Now the projection is ready to be baked onto the mesh. Make sure to set the projection mode from ‘through’ to ‘front’ in the projection pallet. I then add a mask to the layer and begin to cleanup the areas it has projected through the mesh with a soft brush set to black. I then clean up any stretching or messy areas with the same technique.
Chapter 10: Texture the Nose
The nose is a much easier region of the face to project. Just make sure you take full advantage of all the extra angles of the face provided. I normally start by making sure the front projection is clean and then add in the three quarter projections to reduce stretching on the sides. I also use the lattice ‘warp’ tool when necessary. Note how I try to match the size of the nostril fold to make sure I am achieving accurate scale.
Chapter 11: Texture the Eyes
I texture the eyes one at a time. Starting with the left eye I line the photo up with the mesh. Once I am happy with the scale and angle I project. Before I bake it down, I use the warp lattice tool to make sure that the edge and shape of the eye matches. Once I am happy I then bake it down. I then project other photos to reduce stretching on the edge of the nose as well as under the brow.
Chapter 12: Texture the Mouth
The mouth can be a tricky area to project due to the lips rolling into the interior of the mouth. To counter this I create a very small tileable in photoshop with a swatch from the lips, this is the same process we used on the scalp. I find it easier to texture the top and bottom lips separately, because you usually have to angle the camera up or down to get the most coverage on the lip. I start from the corners and work my way inwards.
Chapter 13: Texture Neck
In my case the neck was a little difficult to project, due to the amount of surface area. I used a combination of reprojecting the same texture several times blending the projections with a nice soft brush. As well as using a tiled texture I created out of a swatch from the center of the neck. Make sure to match the width of the neck in the photo texture, with the mesh you are projecting on.
Chapter 14: Cleanup
Once I am happy with all of these specific areas I then create a new layer at the top of my stack and call it ‘cleanup_diff’. This is where I go through and make sure all of the hues and values blend together nicely, and that I don’t have any seams or left over stretching which I may have missed. It is easier to notice these problem areas if you set your viewport view to flat shaded.
Chapter 15: Post Shader Changes
If you end up following along with the full tutorial series on my gumroad, you will find that towards the end of my look development process I am not 100% happy with the final result. For example the hue of the ears and nose are not red enough. This forces me back into Mari to make these changes. I make it a point of doing this because even though you may think you are done with your texturing, you should always leave the option open to go back and make adjustments if you are not happy with your end result.
- Use a soft brush when projecting.
- Zoom into the mesh when projecting to achieve the best resolution.
- Keeping the scale of the texture consistent is key.
- Use landmarks on the mesh to help line up the texture when projecting.