Tech Stack

Unreal Engine 5.7 C++ project, source-controlled in Perforce. Combat and abilities use TInstancedStruct-based composition rather than the Gameplay Ability System. Networking is server-authoritative with fog-gated replication.

At a Glance

Engine

Unreal Engine 5.7 (C++)

Language

C++ for runtime systems; Blueprint for content tuning and prototyping

Source control

Perforce, stream depot //AxonRush/mainline

Networking

Server-authoritative; fog-gated replication; dedicated vs. host-server TBD

Ability framework

Not GAS. TInstancedStruct<FAbility>, TInstancedStruct<FBuff>, etc.

AI authoring

Behavior Trees / State Trees / utility AI TBD

Platform

PC-first

Renderer

UE 5.7 default (Lumen / Nanite — usage TBD per art direction)

Why No GAS?

Unreal's Gameplay Ability System is the standard answer for this kind of game and we're explicitly not using it. Reasons:

• Studio convention. Other in-flight projects use TInstancedStruct for the same problem space; staying consistent reduces context-switching and shared tooling pays off.
• Composition is simpler than GAS's class hierarchy for our actual use case (stat buffs, DoTs, shields, AoE on adjacent tiles). We don't need GAS-specific features like attribute prediction or ability tags.
• Network model is tighter. Server-authoritative with fog-gated replication maps cleanly to plain replicated structs; GAS layers more assumptions on top.
• Smaller learning curve for new engineers — anyone who knows UE C++ can read a struct.

Networking Architecture

Server-authoritative state

• The server holds the full match state — every tile, every unit, every path.
• Clients hold only what their fog permits them to see.
• Path-edit RPCs are server-validated for ownership, adjacency, and path budget.

Fog-gated replication

• Per-player visibility mask updated server-side each tick.
• Tile / unit replication is gated by visibility — players never receive hidden tile state, full stop.
• Bandwidth scales with visible board area, not total board area. Critical for 12-player matches.
• Cheating via memory inspection is mostly defanged: the client genuinely doesn't have data on enemy paths or out-of-fog tiles.

Tick rates

Source Control

• Perforce server: localhost:1666 (development); production setup TBD.
• Stream depot: AxonRush
• Mainline: //AxonRush/mainline (mainline-type stream)
• Per-project p4config.txt at the workspace root — no global P4CONFIG environment variable.
• .p4ignore excludes Binaries/, Intermediate/, Saved/, DerivedDataCache/, IDE files, and p4config.txt itself.

Code Conventions

• TInstancedStruct<T> everywhere, never raw FInstancedStruct.
• ::template Make<Derived>(Value) always — never ::Make(Derived) (which silently slices).
• #include paths are Public-relative: "Folder/Sub/File.h". Don't add module subfolders to PublicIncludePaths in Build.cs.
• New test levels need DirectionalLight + SkyLight or PIE renders black.
• Regenerate UE project files via UBT after structural changes:

  "C:\Program Files\Epic Games\UE_5.7\Engine\Binaries\DotNET\
  UnrealBuildTool\UnrealBuildTool.exe" -projectfiles
    -project="C:\Perforce\AxonRush\AxonRush.uproject"
    -game -rocket -progress

Build

"C:\Program Files\Epic Games\UE_5.7\Engine\Build\BatchFiles\Build.bat"
  AxonRushEditor Win64 Development
  -Project="C:\Perforce\AxonRush\AxonRush.uproject"
  -WaitMutex -FromMsBuild

Future Tech Decisions