3D Asset Workflow: Tintmask

Summary

• A tintmask is a texture, in which different areas of the model are masked to separate color channels
  • The albedo of the model can then be colored in the Editor using these channels
• Tintmasks are very useful for creating multiple differently colored variations of the same model, without having to make Alternative Textures for all of them
• When using tintmasks, it's important to always adjust the default colors to be nice and usable as is
  • Otherwise the model will be black, and additional adjusting is needed
• Some general Editor tips for tintmasks can be found from 3D Asset Workflow: General Tips#Editor

How Tintmasks Work

• Tintmasks are used to control an object's surface color using an RGB mask and color pickers in the Editor
• The mask has 3 layers - 1 in each color channel, and a base layer in the alpha channel
• The colors are blended together based on the masks' grayscale values, and the chosen layer order
• The alpha channel (Base layer) controls the tint's overall blending with the original texture, meaning that an alpha channel with some amount of white is always needed
• The color channels correspond to certain layers by default, but they can be switched around in the meshmaterial
  • The default layers are listed further below
• The tinting is applied through linear interpolation, meaning the the tint is applied more like paint, covering the color on the previous layer, instead of showing anything through
  • This makes the layer ordering important, since the result varies depending on the order in which the layers are applied

Creating Tintmasks

• Tintmasks can be created in Substance Painter
  • The color channels must be made separately on custom texture channels
• The T4_asset_export configuration merges these automatically into a ready tintmask
• In order to get a correct tintmask out of Substance Painter, you must add the proper User channels
  • The texture channels and their corresponding mask channels are listed below:

Texture channel	Color channel	Mask layer	Use
User7	Red	Deco layer	Small details, accents
User6	Green	Simple layer
User5	Blue	Areas layer	Large areas
User4	Alpha	Base layer	Overall blending. Affects every layer

• The user channels are found in the same list as other special channels, like emission or scattering
• You can rename the channels in Painter to make them easier to work with, it won't affect the export config
• The alpha channel (Base layer) is the only mask that is absolutely required
• The Base layer controls the masks' overall blending, so without one, the mask does nothing
• Even when there is the alpha channel in the tintmask, the texture files don't need to have at or ab in their name, unless they really use alpha
• The layer names and uses are arbitrary when it comes to which layer affects what, but it is a good idea to keep things consistent for the sake of level artists
• User channels generally don't show up on the mesh when texturing in Painter, but you can view them by cycling the single channel views
  • Hotkey C to switch to next texture channel, and shift + C to switch to the previous
  • Hotkey M returns you to the material view
• Anchor points help immensely when creating masks based on texture elements
  • Anchor points allow you to refer to an earlier layer in the stack, so any changes made there will transfer over the anchor point
    • In this case, by adding a fill effect to a layer, and to that fill assign the anchor point
  • Here's a video explaining anchor points:

09 - Using Anchors
Video:Sources

Using the Tintmasks in the Editor

• To tint an object, it needs a tintmask, which needs to be applied in the object's meshmaterial
• Name the tintmask texture as [texturename]_tintmask.tga

1. To find the meshmaterial, right click on the object (or its type) and select locate type model resource
2. Right-click the meshmaterial (under MeshMaterialResources) in the model resource's properties, and selecting Locate GUID
3. Click on the three dots at the TintColorMaskTexture and navigate to the mask texture
4. Then save resources or it might not appear
5. In the meshmaterial, you can also set which color channels correspond to which tint layers

• To enable tinting, select EnableTintColor in the ModelComponent properties
• Then you can adjust the tinting with the rest of the settings
• TintLayerOrder determines the order in which the layers are applied

Creating a Tintmask for an Existing Asset

• If you add a tintmask for an existing asset that already has textures, you'll need to:

1. Make the albedo map grey
2. Re-adjust the colors for the default look you want for the asset in the Editor
   • The default look should be nice and not require adjusting each time

Sources

Video 01 : Substance. [accessed June 7, 2018] 09 - Using Anchors Available at: https://youtu.be/w44yuMFtFyM