Mounting¶

Mounting lets you stick an entity to another. The child follows the parent at a given CFrame offset each frame.

The basics¶

To mount an entity, tell it who the parent is and the relative offset.

Entity.SetMount(follower, carrier, CFrame.new(5, 0, 0))

To detach:

Entity.ClearMount(follower)

Dynamic offsets¶

Calling SetMount every frame with a new offset is valid and efficient - no need to clear first. This is how you do orbiting, animated attachments, etc.

RunService.Heartbeat:Connect(function(dt)
    t += dt
    local offset = CFrame.new(math.cos(t) * 5, 0, math.sin(t) * 5)
    Entity.SetMount(follower, carrier, offset)
end)

Chaining¶

Mounts nest - mount an arm to a body, a hand to the arm, a weapon to the hand, etc.

Entity.SetMount(arm, body, cframe)
Entity.SetMount(hand, arm, cframe)

Player entities as parents¶

A player entity can be the parent. The player's physics is client-owned, so Chrono reads its position as a reference - it does not force-set the player's CFrame.

local plrEntity = Holder.GetEntityFromPlayer(player)
Entity.SetMount(attachedThing, plrEntity, CFrame.new(0, 3, 0))

Listening for mount changes¶

Events.EntityMountChanged fires whenever an entity's mount parent changes (including when cleared).

Events.EntityMountChanged:Connect(function(entity, mountParentId)
    if mountParentId then
        print(entity.id, "mounted to", mountParentId)
    else
        print(entity.id, "unmounted")
    end
end)

Things to note¶

• Server-only. SetMount and ClearMount must be called from the server. Mount state is replicated to clients automatically.
• Parents must be registered entities before mounting.
• Mounting continuously zeros the child's linear and angular velocity to keep it locked to the parent.
• Mounting does not affect collision - a child can phase through geometry if the parent moves into a wall.