Added node based web map renderer

map_renderer/README.md

@@ -0,0 +1,67 @@
+# Crusader Map Renderer
+
+Node web app that renders Crusader maps on the server and streams only finished PNG tiles to the browser.
+
+## Goals
+
+- Keep Crusader source assets server-side.
+- Detect maps from `STATIC` and `STATIC_REGRET` automatically.
+- Build map render state on demand after the user selects a map.
+- Serve large maps as draggable and zoomable image tiles.
+- Run locally with Node or inside Docker.
+
+## Local Run
+
+```powershell
+cd map_renderer
+npm install
+npm start
+```
+
+Open `http://localhost:3000`.
+
+Viewer behavior:
+
+- drag with the mouse or one finger to pan
+- use the scroll wheel to zoom directly at the pointer
+- pinch to zoom on touch devices
+- toggle roofs and editor-only elements independently before building
+
+The app expects asset folders under the app root:
+
+- `map_renderer/STATIC`
+- `map_renderer/STATIC_REGRET`
+
+## Docker Run
+
+The Docker image excludes the Crusader assets on purpose. Mount them at runtime so they stay outside the image and are never served directly to clients.
+
+```powershell
+cd map_renderer
+docker build -t crusader-map-renderer .
+docker run --rm -p 3000:3000 `
+  -v ${PWD}/STATIC:/app/STATIC:ro `
+  -v ${PWD}/STATIC_REGRET:/app/STATIC_REGRET:ro `
+  crusader-map-renderer
+```
+
+If only one game is available, mount only that folder.
+
+## Docker Compose
+
+The compose file mounts `STATIC` and `STATIC_REGRET` from the host filesystem into the container as read-only volumes. They are excluded from the image build by `.dockerignore`, so the assets are never copied into the image.
+
+```powershell
+cd map_renderer
+docker compose up --build
+```
+
+## HTTP Surface
+
+- `GET /api/maps` returns the detected catalog.
+- `POST /api/builds` starts or reuses a build.
+- `GET /api/builds/:id` returns build status.
+- `GET /api/maps/:game/:mapId/metadata?buildId=...` returns map bounds and tile settings.
+- `GET /api/maps/:game/:mapId/tiles/:tileX/:tileY.png?buildId=...` returns rendered PNG tiles.
+
+No raw Crusader asset files are exposed over HTTP.