Building a Procedural Maze Generator in UE5 Blueprints — Part 1

Introduction

Welcome to Part 1 of this beginner-friendly series.

In this part, we are not building the maze yet.

Instead, we are building the foundation that everything else depends on.

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What You Will Build in This Part

By the end of Part 1, you will have:

• a clean project structure
• two reusable data structures (S_NeighborInfo, S_MazeCell)
• a fully set up BP_MazeGenerator Blueprint
• all required variables configured
• instanced mesh components ready for rendering later

This is the groundwork. If this part is wrong, everything later becomes confusing.

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Before You Start

Make sure you have:

• Unreal Engine 5.3 or newer
• a new Blank or Third Person project

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Step 1 — Project Setup and Asset Preparation

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What this step does

This step prepares your project so everything stays organized and easy to follow.

Good organization now prevents confusion later.

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Instructions

Step 1.1 — Create a new project

Step 1.1.1 — Open the project browser

1. Open Unreal Engine 5

2. Click:

   Games

Step 1.1.2 — Choose the project template

1. Select:

   Blank

2. Click:

   Next

Depending on your Unreal version, the exact button layout may look slightly different.

Step 1.1.3 — Set the project options

1. Choose:
   • Blueprint
   • Desktop/Console
   • Maximum Quality

2. Give your project a name

3. Click:

   Create

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Step 1.2 — Create your folder structure

Step 1.2.1 — Create the main folder

1. Open the Content Browser

2. Right-click in empty space

3. Click:

   New Folder

4. Name it:

   MazeGenerator

Step 1.2.2 — Create the subfolders

1. Double-click to open the folder

2. Create two more folders:

• Blueprints
• Meshes

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Step 1.3 — Prepare placeholder meshes

For this tutorial, you need two mesh references later:

• one for the floor
• one for the walls

For beginners, the easiest option is to use Unreal’s built-in meshes instead of making your own custom assets.

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Step 1.3.1 — Option A: Use Unreal’s built-in meshes (recommended)

Unreal Engine already includes basic shapes you can use immediately.
We will use these instead of creating custom meshes.

Step 1.3.1.1 — Show Engine Content

By default, Unreal hides built-in assets.

1. Open the Content Browser

2. In the bottom-right corner, click the Settings button (gear icon)

3. Enable:

   ✔️ Show Engine Content

Step 1.3.1.2 — Locate the built-in meshes

1. In the Content Browser, scroll down until you see a folder called:

   Engine

2. Expand:

   Engine → Content → BasicShapes

3. Inside this folder, find:

• Cube
• Plane (optional)

These are built-in meshes provided by Unreal Engine.

Step 1.3.1.3 — Choose meshes for this tutorial

For simplicity, use:

• Cube → for walls
• Cube → for floor (temporary)

We will scale them later, so using the same mesh is perfectly fine.

Step 1.3.1.4 — Create references in your folder (optional but recommended)

To keep your project organized, you can create copies:

1. Left-click on Cube.

2. Drag it twice to:

   MazeGenerator/Meshes

3. Rename:

• SM_Floor
• SM_Wall

If you skip this step, you can still use the Engine meshes directly.
This step just keeps your project cleaner.

Step 1.3.1.5 — Verify the mesh

1. Double-click SM_Floor or Cube

2. The Static Mesh Editor will open

3. You should see:

   • a simple 3D cube
   • dimensions (usually 100×100×100)

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Step 1.3.2 — Option B: Import your own meshes

If you already have custom meshes:

Step 1.3.2.1 — Open the Meshes folder

1. Open the Content Browser

2. Open your:

   MazeGenerator/Meshes

   folder

Step 1.3.2.2 — Import the files

1. Click:

   Import

2. Select your mesh files from your computer

3. Import:

   • a floor mesh
   • a wall mesh

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Connections recap

Project structure created:

• MazeGenerator
• MazeGenerator/Blueprints
• MazeGenerator/Meshes

Mesh preparation options:

• built-in Engine meshes
• imported custom meshes

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Why this matters

• gives you working meshes immediately
• avoids needing external 3D software
• keeps the focus on learning Blueprints

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Common mistakes

❌ Not enabling Show Engine Content
✔️ You won’t see the BasicShapes folder without it

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❌ Looking in your project folders only
✔️ Built-in meshes are inside the Engine folder

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❌ Thinking you need custom assets first
✔️ You don’t—these are perfect for learning

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❌ Creating assets in random folders
✔️ Keep everything inside MazeGenerator

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Expected result

You now have:

• MazeGenerator/Blueprints
• MazeGenerator/Meshes
• access to placeholder meshes for floor and wall use

These will be assigned later in your Blueprint.

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Step 2 — Create the Data Structures

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What this step does

This step creates custom data containers (structs).

These will store:

• maze cell data
• neighbor relationships

Without these, your maze logic cannot function.

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Instructions

Step 2.1 — Create S_NeighborInfo

Step 2.1.1 — Add the structure asset

1. Go to:

   MazeGenerator → Blueprints

2. Right-click in empty space

3. Search for:

   Structure

4. Click Structure in the results menu

5. A new asset will appear, rename it to:

   S_NeighborInfo

Step 2.1.2 — Add the variables

1. Double-click to open the struct

2. Add:

• CellIndex (Integer)
• DeltaX (Integer)
• DeltaY (Integer)
• Default value is 0. You do not need to change this

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Why this matters

This struct tells your system:

• which cell is a neighbor
• in what direction it exists

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Common mistakes

❌ Using wrong variable types
✔️ All must be Integer

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Expected result

You now have a struct that describes neighbor relationships.

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Step 2.2 — Create S_MazeCell

Step 2.2.1 — Add the structure asset

1. Right-click in Blueprints

2. Search for:

   Structure

3. Create the structure

4. Name it:

   S_MazeCell

Step 2.2.2 — Add the variables

1. Double-click to open the struct

2. Click on Add Variable and add:

• Row (Integer)
• Col (Integer)
• bVisited (Boolean, default = False)
• bWallNorth (Boolean, default = True)
• bWallEast (Boolean, default = True)
• bWallSouth (Boolean, default = True)
• bWallWest (Boolean, default = True)

1. Click on Default Values and add the values above

• Default values for integers can remain 0. A checked box in a boolean is always true

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Why this matters

Each cell:

• tracks its position
• remembers if it was visited
• stores all four walls

This is the core data for the maze.

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Common mistakes

❌ Forgetting default values
✔️ Walls must start as True

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Expected result

You now have a full maze cell data structure.

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Step 3 — Create the Maze Generator Blueprint

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What this step does

This creates the main Blueprint that controls everything.

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Instructions

Step 3.1 — Create the Blueprint

Step 3.1.1 — Add the Blueprint Class

1. Right-click inside:

   Blueprints

2. Click:

   Blueprint Class

3. Select:

   Actor - this is the base class for objects that can exist in the world but don’t need movement or player input built in.

4. Name it:

   BP_MazeGenerator

Step 3.1.2 — Open the Blueprint

1. Double-click to open it. After creating and opening a Blueprint, don’t forget to save (Ctrl+S). UE5 won’t always auto-save new assets

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Why this matters

This Blueprint will:

• generate the maze
• store all data
• eventually render the maze

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Common mistakes

❌ Choosing the wrong class type
✔️ Use Actor

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Expected result

You now have an empty BP_MazeGenerator.

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Step 4 — Add Variables and Components

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What this step does

This step defines all settings and components your maze will use.

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Instructions

Step 4.1 — Create Variables

Step 4.1.1 — Open the Variables section

Inside BP_MazeGenerator:

1. Go to:

   My Blueprint → Variables

2. Click the + button next to Variables in the My Blueprint panel. A new variable will appear. Rename it, then set its type in the Details panel on the right.

Step 4.1.2 — Add the maze settings

• Note: In the upper left corner, you must click on compile after adding variables to be able to enter the default values in the Details panel.

Add the following:

• MazeWidth (Integer, Default = 12)
• MazeHeight (Integer, Default = 12)
• CellSize (Float, Default = 200.0)
• MazeSeed (Integer, Default = 42)

Step 4.1.3 — Add the data variables

Add:

• MazeGrid (Array of S_MazeCell)

1. Set the type to S_MazeCell

2. In the Details panel, click the grid/array icon next to the type dropdown to change it from a single value to an Array

• RandomStream (Random Stream)

Step 4.1.4 — Make the main settings editable

For each variable you want to adjust in the level:

1. Select the variable

2. In the Details panel:

   ✔️ Check Instance Editable (You can also click the eye next to the right of the variable name. Open is editable, closed is not)

For this tutorial, that usually means:

• MazeWidth
• MazeHeight
• CellSize
• MazeSeed

You do not need to make MazeGrid or RandomStream editable.

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Why this matters

• lets you tweak maze size and seed in the editor
• keeps your system flexible

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Common mistakes

❌ Forgetting Instance Editable
✔️ You won’t be able to change values in the level

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❌ Making every variable editable
✔️ Only expose the ones you actually want to change

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Expected result

Your main maze settings are now created and visible.

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Step 4.2 — Add HISM Components

Step 4.2.1 — Add the FloorHISM component

• HISM (Hierarchical Instanced Static Mesh) lets you render thousands of repeated meshes efficiently. You’ll use one for floors and one for walls.

1. Open the Components panel inside BP_MazeGenerator

2. Click:

   Add

3. Search for:

   Hierarchical Instanced Static Mesh

4. Click it

5. Rename the new component:

   FloorHISM

Step 4.2.2 — Add the WallHISM component

1. Repeat the process to add a second component

2. Rename it:

   WallHISM

Step 4.2.3 — Assign the floor mesh

Select:

FloorHISM in the components panel at the top left

Then in the Details panel:

• find Static Mesh in the Detaols panel. You may have to expand the category
• assign SM_Floor if you duplicated the mesh
• or assign Cube if you are using the built-in mesh directly

Step 4.2.4 — Assign the wall mesh

Select:

WallHISM in the components panel at the top left

Then:

• assign SM_Wall if you duplicated the mesh
• or assign Cube if you are using the built-in mesh directly

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Connections recap

Components added:

• FloorHISM
• WallHISM

Mesh assignments:

• floor mesh → FloorHISM
• wall mesh → WallHISM

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Why this matters

HISM allows:

• many repeated meshes
• much better performance than spawning separate mesh actors

This is a much better choice for grid-based systems like mazes.

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Common mistakes

❌ Using regular Static Mesh Components
✔️ Use Hierarchical Instanced Static Mesh

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❌ Forgetting to assign a mesh
✔️ Nothing will appear later if the mesh is empty

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❌ Naming components unclearly
✔️ Use FloorHISM and WallHISM so the Blueprint stays readable

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Expected result

You now have:

• FloorHISM
• WallHISM

Both are added as components and both have a mesh assigned.

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What You Have Built So Far

At this point, your system now has:

• organized project structure
• two working data structures
• a maze generator Blueprint
• all required variables
• rendering components ready

You now have the full foundation in place.

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Up Next

In Part 2, we will:

• initialize the maze grid
• implement the recursive backtracker algorithm
• create helper functions
• generate a complete maze in memory

👉 This is where the maze logic begins.

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