Getting Started

Learn how to integrate the Grid Placement System into your Unreal Engine project.

Prerequisites

• Unreal Engine 5.4 or later
• Basic knowledge of Blueprints or C++
• Understanding of Unreal Engine's component system

Installation

1. Install the Grid Placement System plugin from fab.com
2. Enable the plugin in Edit > Plugins, then restart the editor.

3. If the plugin does not appear in your Content Browser:

Blueprint Setup

These instructions assume a fresh setup.
You may reuse or duplicate relevant actors or variables from the plugin content.

Inside UEM_CharacterSetup Blueprint

1. Implement the Interface in Your Placeable Objects Actor

Every placeable object must implement the PlaceableObjectInterface:

Configure the required interface functions:

Get Placement Class (Self is the object itself)

Get Class Placement Type (PlacementType variable: Floor, Wall, or Roof).

2. (Optional) Add Directional Arrow Component (For Oriented Objects)

For objects that need directional placement (chairs, table and etc):

Reference the DirectionalArrow in the remaining interface class:

3. Add Components to Your Player Pawn

• Open your Character Blueprint.
• Add PlacementSystemComponent and PlacementObjectRegistry components.

4. Initialize the System (Same as in UEM_CharacterSetup above)

• Call InitializePlacementSystem from PlacementHelper in BeginPlay.

5. Register Placeable Objects

• Placeable objects can be registered in two ways:

1. By calling RegisterObject (via PlacementHelper), as shown below
   
   

2. And, By using a DataTable that follows the PlaceableObjectDataTable structure and linking it to the PlacementObjectRegistry component.

6. Create the UI

• Add the provided (Default) WBP_PlacementObjectsListWidget to your HUD or Character and configure.
  
  

• If you want to create your own UI, you can create something like this:

Instantiate WBP_MinimalObjectList for each entry in RegisteredObjects and add it to the WBP_MinimalMenu ScrollBox.

This are WBP_MinimalObjectList hierarchy and variable look like

Add OnClick event on ItemButton (in WBP_MinimalObjectList) to call Start Placing from (PlacementHelper)

7. Begin Play

Yeah, play

Input Controls

Once in placement mode, the system provides these controls:

Camera Controls

Object Placement

Special Modes

Common Issues and Solutions

"Directional arrows not showing"

• Cause: Missing UDirectionalArrowComponent or not returned in GetArrowComponent
• Solution: Add arrow component and return it in interface function

"Objects can't be placed on surfaces"

• Cause: Surfaces missing required tags ("Floor", "Wall", "Roof")
• Solution: Add proper tags to placement surface actors (Default tags are "Floor" if not specified)

"Placement system not responding"

• Cause: Components not added to player pawn or system not initialized
• Solution: Add both required components and call InitializePlacementSystem

Important Notes

• Interface Implementation: MANDATORY for all placeable objects - without this, objects will not work
• Directional Arrows: Highly recommended for objects with orientation (chairs, and other Floor object)
• Surface Tags: Ensure your floor/wall/roof actors have correct tags ("Floor", "Wall", "Roof")
• Component Dependencies: Both PlacementSystemComponent and PlacementObjectRegistry are required
• Camera Compatibility: System automatically adapts to camera setup by create Spring Arm Component at Runtime. Third Person, First Person are all supported
• Initialization Order: Always initialize the system before registering objects
• Asset Loading: The system loads required materials and input actions automatically from the plugin content
• Grid Display: Grids appear automatically when you enter placement mode
• Collision: Objects validate placement against other objects and world geometry
• Placement Types: Objects can only be placed on surfaces matching their defined placement type