Grid Selections

One might recall from the User Guide that you can create TileFabs and Bundles using a Grid Selection. A Grid Selection is when you use the Palette or Tile+Painter to make an area selection in a Tilemap. If the Bundler tool sees an active Grid Selection, it will ask if you want to use it. If you agree, the selection is used to limit what is archived. Normally, the Archiver grabs every tile on a Tilemap, and every Prefab parented to the Tilemap’s GameObject.

One of the things that’s stored in a Bundle is the BoundsInt for what was archived. When archiving a GridSelection, that selection supplies the BoundsInt.

Say that you want to paint (load via TileFabLib) a Chunk at Vector3Int.Zero. All the tiles in the bundle will be painted relative to Vector3Int.Zero as shown below. In other words, the stored locations of the tiles in the bundle are pure Tilemap “grid” coordinates regardless of where the Tilemap’s origin was placed.

Note that all the tiles and Prefabs are placed relative to the position of the Chunk at the lower left corner, i.e., to the upper-right of the placement position for the Chunk.

Having a good understanding of this concept is important if you don’t want to get confused by what’s next.