Skins Creation - Best Practice

Part 1 - Skin Creation

Materials You Need To Receive From The Car Modelers

The devmode version of the car, to be loaded in the viewer (if without physics) or devmode (if with physics)
An export of the body in .3DS format/Max Coordinates, so that you can import the 3D model in Photoshop CC
A TIFF/TGA storing the UVW unwrap wireframe in native 4096x4096 px resolution.
A TIFF/TGA storing the Ambient Occlusion Baking to be mixed in the skin, in native 4096x4096 px resolution.

Software Requirements;

Source File Requirements;

.PSD file @ 4096x4096 px / 72dpi
Any data you collected for the task (logos, stickers, fonts etc) stored into properly organized folders
Any font you collected for the task, if commercial, please, contact the Studio for approval

Destination File Requirements;

Collect the data for the task;

Usually a great skin starts from a good image/data gathering

Collect all the logos and decals image in a project folder for any future reference and usage
Prefer high resolution logos with transparency.
Prefer trustful sources, like original owner web sites
Be sure the logo you’re collecting it’s exactly the one used in the livery
Be sure all the RGBs colors are matching the original logo
Be sure your Logo sources are in RGB format. If not, proceed with a conversion
If you can’t find the Logo, you can build it from scratch, using vectors and fonts, in Illustrator

Maintain a stable pixel/meter ratio;

Another secret for a good skin is to maintain a stable pixel resolution between various elements

Prefer Smart Objects to Rasterized Layers for a nondestructive workflow
Never scale up a raster layer in the skin. Always starts from an higher (or same) resolution element.
When scaling down a raster layer, always use the Bicubic Sharper Resampling Algo
Always prefer to draw the main paint scheme in Illustrator (or any other Vector Graphics Software)
If you draw the paint scheme with vectors, keep a source file for that job, for any future usage

Work with Layers and Groups;

Always good to produce well organized PSD files. This helps any future usage and does improve any debug/update process.

You’ll be likely using lots of Layers so take advantage of Layer Groups, which act as folders for layers you choose.
Use a Group for any major aspect of your skin, like “Logo Decals”/”Common Stickers”/”Carbon Bits”/”AO Map” etc…

Always prefer Layer Masks to the Eraser Tool;

Always good to work nondestructive as much as possible. This helps any future modification and does improve debug/update process.

Instead of deleting parts of your elements to match the original skin, use layer masks
If you have a chunk of elements that needs to be masked all together, always prefer a Layer Group Mask

How to manage the Ambient Occlusion layer;

Current shader model does still require for an AO map (our car art team will be providing that map), baked into the diffuse map

Use the AO map in the Diffuse map only (remove from the reflection/specular maps)
Be sure the blending is a Multiply, happening on top of the stack (to be applied to the entire skin)
Depending on the AO strenght, keep a subtle presence of that AO map. We don’t want overdone presence of that map so typically a range between 20 and 40% it’s enough.

Always use extra padding around your islands for MIP maps;

Good and stable Mip Maps are requiring padding

Be sure that you have (at least) 5/10px of extra padding around color islands to avoid pixel glitches on lower Mip Maps

Check your Skin elements are all Albedo compliant;

The graphic engine and tonemapper, does require colors to be Albedo compliant to stay in the correct and available range

Normalize all your elements to be Albedo compliant
You can use the Photoshop Histogram to check that the Median value of your elements and colors it’s not exceeding the range
The RGB allowed range starts from 20,20,20 for pure Blacks to 200,200,200 for pure Whites. Exceeding the range will produce clipped colors and flat looking models
You can either pre-Normalize all your elements, prior placing those in the skin layers, or normalize when placed
Once you are sure all your layers/elements are Albedo compliant, you can add an overall Level Adjustment Layers, on top of the entire stack, so that you can fine tune the overall output
Instead of raster layers for base colors you could use a Layer Style – Color Overlay applied to those parts. This would allow you to choose and change the base color Realtime without any destructive process involved. Very useful for Albedo balancing in a nested stack of layers
For more generic information about albedo; GUIDELINES FOR ARTISTS - DX11 and PostFX Art Integration (ongoing wip)