On August 7th, 2019, user Penney16 figured out how to add vertex light and color to a model in BfBB. This guide will help you with adding vertex color to your models and custom models!
To add custom vertex color or vertex light to a model, like shown here, follow these steps:
Painting Vertex Colors in 3ds Max
If you already have a model with vertex colors which you want to import, skip to the #PIPT Settings section.
In 3ds Max, open the model you wish to add vertex colors to. Next, select ONLY the model, no bones, and click the "Modifiers" tab, which is the blue rainbow looking thing. Once there, click the "Modifier List" drop-down menu, and scroll down until you find "VertexPaint". Click on it to add the modifier to the model, and a menu with vertex paint tools will pop up on the left of 3DS Max.
Once the vertex paint modifier is added, you can now add custom colors and light to your model! In the left window that popped up you have a few tools.
The yellow bar you see (in which by default is black instead of yellow) is where you can select a custom color. The pink eraser icon on top of it is the eraser, allowing you to erase painted color. The red brush icon above the eraser allows you to paint a custom color, or multiple colors, while the paint bucket icon on the left of the paint brush lets you paint the model all one color of which you've chosen. Once you use these tools, and paint or color your model how you want, export your model as DFF with the recommended settings and save it wherever you want.
The last step, once your model is saved where you want it, open Industrial Park and the HIP/HOP you wish to add the model to. Using either the Import Models dialog, or the Edit Data dialog of an existing MODL asset (if you want to replace an existing model), import your new model. You can now use a SIMP, PLAT or any other placeable asset with your new model. If you're importing a new model, or replacing an existing model which previously didn't have vertex colors, you have to follow the steps below:
First, go to your level's HOP archive, in the "DEFAULT" layer, find the Pipe Info Table (PIPT) asset, and click "Edit Data". If there isn't one, you can place one with a template.
Next, click the PIPT entries drop-down arrow, or select the little box with three dots that appears, to edit the entries in the PIPT asset.
Next, click "Add" and a new entry will be added, next click on that entry to edit it. Now this is the important steps. Add your models Asset ID in the "ModelAssetID" field, and change the "LightingMode" field to 1. If your model has transparent vertex paint, set your desired blend modes to whatever effect you want or leave them at none.
Once this is all done, save your changes if you haven't already, and now your custom model's vertex color or vertex light should display properly in-game! If you also need a visual tutorial for this too, a video tutorial can be found here.
With enough time and effort using this guide, you can achieve things like this.