If you want, I can:
Which of those would you like?
MapGen v2.2 is a community-developed tool used to create custom world maps for Hearts of Iron IV (HOI4). It simplifies the modding process by allowing users to generate essential map files—such as province layouts, terrain, and heightmaps—from simple image inputs rather than drawing thousands of pixels manually. Core Requirements for Development
To successfully generate a map using version 2.2, your input files must meet specific technical criteria to avoid crashes or visual glitches:
Resolution: Files should ideally be 5632x2048 to fill the standard game map, or follow a consistent 2.75 aspect ratio.
Format: MapGen requires 24-bit BMP files for land and sea inputs.
Specific Hex Codes: The tool recognizes only three primary colors for the base land input: Land: #9644c0 Ocean: #051412 Lake: #00ff00. Key Features & Workflow
Direct Export: Version 2.2 introduced a "one-click" export feature that sends generated files directly into a blank mod template for immediate testing in-game.
Province Generation: The tool automatically creates a provinces.bmp and definition.csv. Users can adjust the "Province Size" slider within the GUI to control how many provinces are generated.
Terrain Mapping: By providing a terrain input image, MapGen assigns biomes (plains, mountains, forest) based on the colors in your image. Common Troubleshooting
Four-Corner Error: Avoid "cross" intersections where exactly four provinces meet at a single point, as this can cause visual bugs. Shift a single pixel to break the intersection.
Heightmap Multiples: Ensure your map dimensions are multiples of 64 (e.g., 5632 x 2048) to prevent "Height map height is not a multiple of 64" errors.
Launch Settings: Always run HOI4 with the -debug launch option enabled to see error logs and use the "Nudger" tool for fine-tuning after generation. How to Make a Hoi4 Custom Map Mod in 2024
On the technical side, the team has optimized the threading model.
The standout feature in the v2.2 changelog is the complete rewrite of the hydraulic erosion algorithm.
In previous versions, water flow was simulated via a basic particle system that often resulted in jagged, unnatural riverbeds. v2.2 introduces a node-based thermal erosion pass. What does this mean practically?
For developers, this means less time manually sculpting terrain masks and more time placing gameplay elements.