CustomRoadSnap — Cities: Skylines II Mod

A mod for Cities: Skylines II that snaps roads to a configurable angle while the Net Tool is active.

⚠️ Experimental Mod

This mod is currently in experimental stage. Bugs may occur during gameplay. Please test the mod on a test save before using it on your main city to avoid potential save corruption or unexpected behavior.

Features

• Configure the snap angle (1–90°) via a slider in mod settings
• Default: 30° (gives axes at 0°, 30°, 60°, 90°, … — ideal for hex-grid cities)
• Toggle button in the Tool Options panel when the road tool is active
• Keyboard shortcut to toggle snapping on/off (configurable in mod settings)
• Minimal performance impact — only active when the Net Tool is selected

Todo-List

• Add Localization
• Add UI slider next to the Button in the Road tools to quickly edit angles

📦 Installation

Option 1: Paradox Mods (Recommended)

1. Subscribe to the mod on Paradox Mods
2. The mod will be automatically downloaded and installed
3. Enable the mod in Options → Mods menu in-game

Option 2: Manual Installation (GitHub)

1. Download the latest CustomRoadSnap-v1.1.zip
2. Extract the ZIP file
3. Copy the contents to:
   %AppData%\..\LocalLow\Colossal Order\Cities Skylines II\Mods\CustomRoadSnap\
4. Enable the mod in Options → Mods menu in-game

Building from Source

Prerequisites

• Visual Studio 2022+ with .NET Framework 4.8
• Node.js 18+
• Cities: Skylines II installed (game DLLs referenced via Library/)

Steps

# Install UI dependencies
cd ui
npm install

# Build UI
npm run build

# Build C# project
# Open CustomRoadSnap.slnx in Visual Studio and build

How It Works

The mod uses HarmonyX to patch the game's road placement system:

• CustomRoadSnapPreSystem removes the vanilla 90° snap flag before NetToolSystem runs
• CustomRoadSnapPostSystem computes snap axes from your configured angle and injects guide lines
• A Harmony postfix on GetRaycastResult snaps the cursor position to the nearest axis
• The snap angle is read dynamically every frame — changing it in settings takes effect immediately

The UI button is injected into CS2's MouseToolOptions panel using the official CS2 modding moduleRegistry.extend pattern.

License

GNU GPLv3