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HELIX is in Early Access Preview. Some features and documentation may be non-functional or out of date.

Create or Edit a World Using Build Mode#

A guide to editing, asset placement, dependencies, and map handling in HELIX Build Mode

1. What is Build Mode?#

  • Build Mode is a sandbox runtime editor in HELIX.
  • It allows you to create Worlds by simply dragging and dropping assets — no coding required.
  • You can:
    • Place meshes, materials, and prefabs.
    • Edit maps in real time.
    • Add scripts and dependencies directly from within the session.
  • Availability:
    • Pre-Alpha & Closed Alpha: Single-player worlds only.
    • Open Alpha (Q4 2025): Multiplayer Build Mode with collaborative building support.

2. Accessing Build Mode#

  • Build Mode is only available in single-player worlds (for now).
  • To enter Build Mode:
    1. Create a new world via Create World.
    2. Or join an existing world via Join World.
  • Not available if:
    • You create a multiplayer server.
    • You join an existing multiplayer session.
  • Shortcut: Press N to toggle Build Mode once inside a world.

3. Object Placement#

  • Basic: Drag-and-drop objects directly into the scene.
  • Works with static assets (meshes, props) and materials.
  • Vehicles & complex physics objects:
    • Dragging them directly can cause physics glitches.
    • Best practice: Hold Shift while dragging.
      • The object only spawns when you release the mouse, reducing instability.

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4. Managing Dependencies#

  • Worlds start with no dependencies.

  • Open the Vault dialog (same as main menu) from Build Mode to:

    • Add dependencies.
    • View and manage downloaded packages.

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  • Added dependencies appear in:

    • Dependencies list.
    • Downloads tab (with live progress).

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  • Pack files: If dependency is a .pak, its assets mount into the Library tab.

5. Using Vault Assets in Build Mode#

  • You can place meshes, materials, and native Unreal levels from dependencies.
  • Level Instances:
    • Dragging a native level creates a level instance.
    • Great for static content, but limitations exist:
      • The level reference replicates in multiplayer.
      • Objects inside do not replicate — e.g., a car placed inside appears differently for each client.
  • Solution: Convert static/native levels into dynamic/editable maps using the Dereference tool.

6. Player Start Actor#

  • Place a Player Start Actor to define:
    • Where your avatar spawns in single-player.
    • Teleport location in Build Mode.
  • Saved/published spawn points persist when reopening the world.

7. Reference Tracking Limitations#

  • No automated warnings for removing dependencies with referenced assets.
  • Removing such a dependency will break references after reload.
  • Manage dependency cleanup manually for now.

8. Downloading New Assets During Build#

  • From the Vault panel inside Build Mode:
    1. Download a new package.
    2. Add it as a dependency.
    3. Place its assets immediately in your scene.
  • Active downloads appear in the Vault list and Downloads tab.

9. Materials (Work in Progress)#

  • Basic material placement works, but there are known glitches.
  • Drag-and-drop may fail in certain cases until the feature is finalized.

10. Best Practices#

  • For multiplayer compatibility, keep interactive objects outside static/native level instances.
  • Use Shift + Drag for large/complex objects.
  • Convert maps to dynamic ones if they’ll contain interactive content.
  • Save workspaces frequently.