Creating Entities

​To create a Entity prefabs from Unity prefabs in the Project view, select the prefab you want to create an entity from and right click it. Then select 'Modbox/Create Modbox Entity Prefab(s)'. You can also select multiple prefabs at once for quick creation. Along with the entity prefab a 'Entity Asset' will also be created that links to the prefab.

  • 'Keep Prefab Connection' means the prefab is then kept as a nested prefab in the entity prefab.
  • Entities should not have Rigidbodies - since Modbox will create Rigidbodies for it
  • If it has Colliders - they need to be convex unless the entity is set to 'AlwaysKinematic'. This is because Unity does not allow non-convex colliders on dynamic rigidbodies. For complex static structures (like arches), where you want to not have a convex collider (where changing to convex would fill in holes in the collider), use 'AlwaysKinematic', which will set it to never be non Kinematic and always static.

For creating a Entity prefab from a gameobject added to the scene, right click on it in the hierarchy and select 'Modbox/Turn GameObject Into Entity Prefab'

Place your Entity prefab in your mod folder (usually in a 'Entities' folder, but not required). It should then show up as a option to build with.

Entity Scale \ Position \ 'AutoScale'

Entities should be facing up (the Y direction). When placing in the Desktop Editor or with the 'Entity Brush' surface mode, it'll rotate based on the angle it's being placed on - so a 'rocket thruster' should have it's exhaust pointed up, a button/screen should have it's button/screen pointing up.


For best use of the grid/scaling system, the center / pivot point of the entity (at 0,0,0 position) for most entities should be the center of the Entity.

When a Entity prefab is selected the 1m bounds are shown with a cube wireframe. If the entity is a structure that is meant for the grid system - like any of the primitives - it should be centered in the 1 bounds and fit into it exactly. Then Autoscale in it's 'EntTransform' script can be set to 'By 1 Bounds', meaning it'll scale assuming the Entity is 1m size (so if the gridsize is set to 0.25, it'll just scale the Entity to 0.25).


For entities that are meant to always be placed on a surface / wall, the center should be the bottom center position.

By default when scaling the 'Max Render Bounds' will be used.  Most entities are 'Autoscaled' when creating ingame by a VR players to the VR players scale


To generate Icons for the Entity, enter play mode in Modbox with the 'Enable Auto Icon Making' option in MBStartup on. It'll render the object and save as a sprite.

Entity Components

Entities have a special Monobehavior type for components called 'ComponentEntity', and a inherited 'ComponentEntityWithVariables'.

Entity Group Asset

Entity prefabs can have more than one Entity in a single prefab. This is good if you want them to have different rigidbodies in play mode (such as a Spinner Hinge Joint object, which has a different body for the top and bottom, and connects them with a physics joint in play mode) - or have child components of the same type that should be editable (like multiple wheels on a car). See examples like HingeJoint / Spinner.