S1MAPI

S1MAPI - Schedule 1 Mapping API

S1MAPI is a mapping and construction library for Schedule 1 mods. Create procedural meshes, build structures, and load GLTF assets without asset bundles.

Documentation • GitHub Repository

What S1MAPI Does

• Procedural Meshes: Generate 3D shapes at runtime such as boxes, spheres, cylinders, and capsules
• Building Construction: Create buildings with walls, floors, roofs, windows, and furniture
• GLTF Loading: Import external 3D models without extra runtime dependencies
• Update Resilience: Avoid ScheduleOne types so mods survive game updates more cleanly

Installation

For Players

If a mod you want to use requires S1MAPI:

• Download the S1MAPI package
• Extract the package - it includes UserLibs/S1MAPI_Mono.dll and UserLibs/S1MAPI_Il2Cpp.dll
• Copy the correct DLL for your Steam branch into your game's UserLibs folder:
• Regular Steam branch (default): Use S1MAPI_Il2Cpp.dll
• Alternate Steam branch: Use S1MAPI_Mono.dll
• Launch the game - S1MAPI will load automatically with MelonLoader

To check your Steam branch: Right-click Schedule 1 in Steam -> Properties -> Betas. If it shows "None" or no selection, you are on the regular branch and should use the Il2Cpp DLL.

For Developers

To use S1MAPI in your mod project:

• Add the Mono S1MAPI DLL as a reference to your mod project
• Build your mod against the Mono DLL - it works for both runtimes
• Tell users to install S1MAPI separately with the correct DLL for their Steam branch

Building From Source

• Clone the repository
• Copy local.build.props.example to local.build.props
• Edit local.build.props and set your game installation paths
• Build with dotnet build S1MAPI.csproj -c Mono or dotnet build S1MAPI.csproj -c Il2cpp

Requirements

• Schedule 1
• MelonLoader 0.7.0+

-.NET Framework 4.7.2+ or.NET 6.0+

Learn More

• Getting Started
• Examples
• API Reference
• Contributing Guide

License

GNU GPL v3 License - see the LICENSE file.