Installation

This page takes a fresh project to "plugin enabled and configured". It takes about ten minutes.

#Requirements

#Step 1 — Install the plugin

From Fab: open the Epic Games Launcher → Fab Library → Mass Projectile Subsystem → Install to Engine. The plugin appears under Engine/Plugins/Marketplace.

Manually (project plugin): copy the MassProjectileSubsystem folder into <YourProject>/Plugins/. Create the Plugins folder if it does not exist.

#Step 2 — Enable it

1. Open your project and go to Edit → Plugins.
2. Search for Mass Projectile, tick Mass Projectile Subsystem, and accept the dependency prompt.
3. Accept the notice about Mass Gameplay being experimental.
4. Click Restart Now.

Blueprint-only project, plugin installed in the project folder: the editor asks to compile the plugin modules on first launch. Click Yes. This needs a C++ toolchain (Visual Studio 2022 with the Game development with C++ workload on Windows). Engine installs from Fab come precompiled.

#Step 3 — Create the Projectile collision channel

Every projectile type traces against a collision channel. The shipped types use the project's first custom channel (ECC_GameTraceChannel1), expected to be an object channel named Projectile that other objects Block by default.

1. Open Edit → Project Settings → Engine → Collision.
2. Under Object Channels, click New Object Channel…
3. Name it Projectile, set Default Response to Block, click Accept.

This writes the following into Config/DefaultEngine.ini:

[/Script/Engine.CollisionProfile]
+DefaultChannelResponses=(Channel=ECC_GameTraceChannel1,Name="Projectile",DefaultResponse=ECR_Block,bTraceType=False,bStaticObject=False)

Already using custom channels? If ECC_GameTraceChannel1 already means something else in your project, create the Projectile channel anyway (it gets the next free slot). Then open each projectile type and set Projectile Ballistics → Trace Channel to Projectile. See Projectile Types.

To make something bullet-proof (a trigger volume, a pickup, a character's capsule while the mesh takes hits), set its collision response to Projectile = Ignore.

#Step 4 — Name the physical surfaces (recommended)

The shipped surface table and physical materials (/MassProjectileSubsystem/Surfaces/PM_*) use surface slots 1–6. Naming them makes every dropdown readable.

1. Open Project Settings → Engine → Physics and scroll to Physical Surface.
2. Enter these names:

Unnamed slots still work. The names are display only. If your project already uses slots 1–6 for other materials (for example SurfaceType1 = Flesh), read Physical Surfaces → Using your own surfaces before continuing.

#Step 5 — Check the plugin settings

Open Project Settings → Plugins. The plugin adds two pages:

Every slot already points at the shipped content under /MassProjectileSubsystem/, so nothing has to be assigned to get started. Details: Project Settings.

#Step 6 — Verify

Open /MassProjectileSubsystem/Demo/Maps/L_MassProjectileDemo and press Play. Hold the left mouse button: tracers fly, hit the range walls, leave decals, and ricochet or punch through depending on the wall material. Continue with the Quick Start.

#Where the content lives

Enable Show Plugin Content in the Content Browser settings to see it.

/MassProjectileSubsystem/
├── Types/      EC_Projectile_Rifle, EC_Projectile_Shell, EC_Projectile_Plasma   ← projectile types
├── Surfaces/   PM_Concrete, PM_Metal, PM_Wood, PM_Dirt, PM_Glass, PM_Water      ← physical materials
├── FX/         NS_MassProjectile, NS_ProjectileImpactFX, NS_ProjectileSmokeTrail, debris meshes
├── Decals/     M_ImpactHoleDecal (impact/exit) and M_ProjectileBoreDecal (bore) + hole textures
├── Audio/      SW_Flyby_Rifle / Shell / Plasma, ATT_BulletFlyby
├── Materials/  MI_Breachable_* demo wall materials
└── Demo/       L_MassProjectileDemo, BP_DemoShooterPawn, BP_DemoGameMode, input assets

The plugin never references /Game content. You can delete the Demo folder once you no longer need it.