COLMOD - Collision Mesh Generator for Blender

A Blender addon for creating collision meshes optimized for game engines like Unreal Engine.

Features

• Create Mass Hull: Generates a single convex hull collision around all selected objects or face groups
• Create Individual Hulls: Creates separate convex hull collisions for each selected object or face group
• Create Box Collision: Creates axis-aligned bounding boxes around selected objects or vertices

Installation

1. Download the addon as a ZIP file
2. In Blender, go to Edit > Preferences > Add-ons
3. Click Install... and select the ZIP file
4. Enable the addon by checking the box next to "COLMOD - Collision Mesh Generator"

Usage

Panel Location

The COLMOD panel appears in the 3D Viewport > N-Panel > COLMOD

Controls

• Decimation Ratio: Adjusts the simplification level (0.01-1.0, lower = more simplified)
• Create Mass Hull: Single convex hull for all selected objects
• Create Individual Hulls: Separate convex hull for each selected object
• Create Box Collision: Axis-aligned bounding box for selection

Workflow

Object Mode

1. Select one or more mesh objects
2. Click the desired collision button
3. Collision mesh(es) will be created with appropriate naming

Edit Mode (for face/vertex selection)

1. Enter Edit Mode on a mesh
2. Select faces or vertices
3. Click the desired collision button
4. Collision will be created from the selected geometry

Naming Conventions

• UCX_: Convex hull collisions (Unreal Engine standard)
• UBX_: Box collisions (Unreal Engine standard)

Each collision object gets a unique name with an incrementing suffix (e.g., UCX_MyObject_01, UCX_MyObject_02)

Technical Details

• Blender Version: 5.1+
• Material: Collision meshes use a "collision" material (loaded from materials.blend or created as fallback)
• Original Meshes: Never modified - all operations create new objects
• Selection: Original selection is preserved after collision creation
• Mode: Original mode (Object/Edit) is restored after operation

Requirements

• Blender 5.1 or later
• The addon includes a materials.blend file with a pre-configured collision material

License

This addon is provided as-is. See LICENSE file for details.