The Problem
Turning map data into a visually striking poster typically requires graphic design software or paid services. Developers and designers who want programmatic, repeatable map art have few good options — most either require manual design work or lack the customization depth needed for varied aesthetics.
What This Does
maptoposter is a Python CLI that generates minimalist map posters from any city using OpenStreetMap data. The core entry point is createmapposter.py, which accepts a city, country, theme, and radius, then renders a styled poster as a PNG. The themes/ directory holds 17 JSON configs (e.g., noir.json, japaneseink.json) that define color palettes, road styling, and background treatments. Sample outputs in posters/ show the range — from veniceblueprint to singaporeneoncyberpunk.
The project is intentionally small: one Python script, a requirements.txt, and JSON theme files. The README documents usage thoroughly with city-specific examples and a distance guide for choosing map radius.
How To Use It
Setup: Install dependencies with pip install -r requirements.txt. No lockfile is present, so your exact dependency versions may vary.
Configuration: No environment variables or API keys are required. Themes are selected by name from the themes/ directory.
Running it: Execute the CLI directly:
python createmapposter.py --city "New York" --country "USA" --theme noir --distance 12000
The --list-themes flag shows available themes. Output PNGs are written to posters/ with a timestamped filename.
Real-World Use
A real estate marketing team could generate branded posters for property listings. For a listing in Barcelona's Eixample district, run:
python createmapposter.py -c "Barcelona" -C "Spain" -t warm_beige -d 8000
The resulting PNG can be embedded in a listing page, social media post, or printed material. The script's determinism (same inputs → same output) makes it suitable for batch generation across multiple cities.
Code Health & Issues
Med - No test files - the single Python script has no test coverage. Map rendering logic (coordinate transforms, theme application) is untested, so regressions are likely with future edits. Med - No CI/CD pipeline - no .github/ or CI config exists. There's no automated gate to catch syntax errors or dependency breakage. Low - No dependency lockfile - requirements.txt pins no versions. A future pip install could pull breaking changes from upstream packages. Low - No input validation - the CLI accepts arbitrary city/country strings; invalid locations will likely produce an unclear error or empty output. No validation of the --distance range either. Low - Repo hygiene - the posters/ directory contains 14 generated PNGs committed to the repo. These are artifacts, not source, and bloat the repository size.
The codebase is too small to flag deeper architectural issues. The README is well-written and the theme system is a clean separation of concerns.
The Bottom Line
This is a solid, focused tool for generating map posters programmatically. It won't replace a graphic designer for complex compositions, but it's ideal for developers who need repeatable, themed map images for web, print, or marketing use. The main risks are the lack of tests and version pinning — acceptable for a personal project, less so for production use without adding those safeguards.