Terrain brushes

A terrain brush picks the right tile for you. You point at the map and say “put grass here”, and GridCraft figures out which corner, edge, or fill tile fits based on what's next to it. That's a Wang set.

Wang sets

A Wang set defines a list of colors (grass, dirt, water, etc.) and assigns colors to each corner or edge of every tile in your tileset. The solver then knows which tile fits where: if the cell you're painting needs grass on the top-left corner and dirt on the others, it finds the tile that matches.

You can define two flavours:

• Corner: each tile's four corners carry a color. Good for blob-style transitions where anything can touch anything.
• Edge: each tile's four edges carry a color. Good for road / path tiles where connections run along edges, not corners.

Painting

Pick a Wang set, pick a color, and paint. The brush updates the tile under the cursor and the surrounding tiles to keep edges consistent.

Files and round-trip

Wang sets are stored on the tileset. They export in Tiled JSON as wangsets on the tileset object, and round-trip with Tiled. Other exporters (Godot, GameMaker, etc.) ignore Wang sets: the painted result is in the tile layer data, that's what ships.