Unreal Painter

This project is an easy to use mesh painter for the Unreal Engine.
You can use it for in-game painting or as a damage system. There are two modes Dynamic or Baked.
You can define textures (RenderTargets) and then use it in the material.

Inspired by Ryan Brucks and Tom Looman

Install

Simply add this project to your content folder in your Unreal Project.

How to Use

Simply add the BC_PaintSystem component to your Actor.

Now the meshes and the maps to be used must be set. The SetupMeshes function is used for this.
The function requires a Meshes array as BST_PaintSetupData. Struct BST_PaintSetupData:

• Mesh: On which mesh to paint
• Material Index: Which material index should be used
• Unwrap: Is used when the PaintSystem is bundled. See here: Baker
• UVsOffset: If your UVs are outside the normal 0-1 range. e.g. MetaHumen Body
• Maps: BST_PaintMapData, Which maps should be used

Struct BST_PaintMapData:

• Name: Map name
• Type: Color or Normal
• Size: RenderTarget Size

Dynamic or Baked

There is a dynamic and a baked mode.
In dynamic mode, a new unwrap is always created based on the current location position. In baked mode, you create your own unwrap based on the pre-skinned data. You can use the Baker for this.
Dynamic mode requires a SceneCaptureCamera and is therefore more precise. But it is also more expensive in performance.

Setup Dynamic Mode

To use Dynamic mode, you must do the following:

• Add a SceneCaptureCamera2D
• Call SetupSceneCapture add the the new SceneCaptureCamera2D
• Set the bool Dynamic in the BP_PaintSystem Component

Now you can start painting! With the setting Delay Between Dynamic Unwrap you can control how long the last unwrap capture may have been. For example, if you want to paint on the same unwrap several times in a frame, this will help with the performance.

Use Baker

There is a Baker Actor to facilitate the creation of the baked unwrap.
The actor is called BP_CoreUVBaker. Simply drag it into the scene.
Now set the mesh of which you want to have the unwrap and then click on.
Capture SkeletonMesh or Capture StaticMesh, depending on what you want to capture. \

The unwrap is now created in the Texture Target UVs.
Now click on Add Dilate to get an extension of the UVs.
Now you can click on Save Dilate Texture and the unwrap will be created in the folder of the Actor.
This unwrap can now be used in Setup Meshes.

Paint

To paint, you only need to call the function Paint with Direction.

Function Inputs

• Map: Name of the Map.All maps with the same name are used. No matter which mesh the map has.
• Location: World Location
• Normal: The direction in which you want to project.
• Bone Name: Is only used for SkeletonMesh that are baked. The hit location is calculated back to the preskinned location.
• Rotation: Project Rotation
• Size: Size in World Units
• Opacity: Opacity
• Brush: Project texture
• Bush Shape: You can project with a box or a capsule Shape.
• Brush Length: How long the bush should be. So you can also paint the back of meshes.

Function Outputs

The output forwards all inputs, making it easier to build chains of nodes.
You also get the painted render targets.

Demo Files

In the folder Demo you will find some examples of how to use the system.
All blueprints react to PointDamage.

Tested

Currently only tested on PC with Unreal 5.3.
But I think it should run in most versions of Unreal and with the baked version it should run on most devices.