📖DOCS

Modular Building System is a data-driven C++ plugin for adding runtime construction gameplay to Unreal Engine projects.

It provides grid and socket snapping, placement validation, structural support checks, multiplayer replication, and HISM or Actor-based rendering for different types of buildings.

KEY FEATURES

Modular and Data-Driven Design 🔧

• Configure building definitions, rendering modes, placement settings, snapping, costs, and effects through Data Assets

• Runtime building placement, rotation, movement, and demolition

Grid and Socket Snapping 📐

• World-space grid snapping with a configurable grid size for each building

• Socket-based modular snapping with configurable groups, directions, rotation alignment, and local transforms

• Supports multiple compatible snap points between building modules

Placement Validation ✅

• Placement validation using building collision

• Visual feedback for valid and invalid placement states

• Basic structural support checks and collapse detection for unsupported building pieces

HISM and Actor Rendering 🏗️

• HISM rendering for efficiently managing large numbers of static building pieces

• Actor rendering using Blueprint or C++ classes derived from ABuildingEntityActor, suitable for doors, containers, crafting stations, animated structures, and other interactive buildings

Multiplayer Replication 🌐

• Server-authoritative building operations

• Replicated building creation, movement, demolition, and entity updates

• Synchronization of existing buildings for late-joining players

• Listen Server multiplayer support

Building Costs 📦

• Building costs configured through Cost Sets

• Evaluator classes are used to connect building costs with project resource, inventory, currency, or other gameplay systems

• Final cost validation and resource consumption can be performed by the server

Niagara Effects ✨

• Niagara effects can be played when buildings are placed or demolished

• Supports project-default and per-building effect configurations

Save and Reconstruction 💾

• Collect building records for use with project save systems

• Rebuild the building world from saved records

• The plugin does not require a specific save framework

DEMO PROJECT

The included third-person demo project contains:

• 20 modular building pieces

• Building selection UI

• Enhanced Input setup

• Collision configuration

• Asset Manager configuration

• Grid and socket snapping examples

• HISM and Actor building examples

• Replicated interactive door

• Structural support demonstration

• Placement and demolition Niagara effects

• Listen Server multiplayer example

Requirements

- Niagara: Required for all supported Unreal Engine versions. Niagara is a built-in Unreal Engine plugin.

- StructUtils: Required only for Unreal Engine 5.4. StructUtils is a built-in Unreal Engine plugin. In Unreal Engine 5.5 and later, the required struct utilities are provided by CoreUObject.