Auto Tile Mapping

Auto Tile Mapping chooses terrain artwork as a painted Scene cluster changes. Prepare connected edges, corners, and interior artwork before defining the mapping. Four unrelated pictures do not supply a complete terrain pattern.

Prerequisites

Open a Tileset containing cut or authored tiles and a 2D Scene with an editable Tile Layer. A complete 3 × 3 terrain block is a useful first input: its corners, edges, and center supply fallback artwork for larger shapes. Retain the source layout and a project backup.

Define a Cluster

1. Choose Auto Tile Mapping in Tileset Editor Modes.
2. If the Tileset has no mapping, choose Create Auto Tile Mapping. The mapping belongs to this Tileset.
3. In Tile Sheet, choose Define Cluster Rectangle (R) and box-select the terrain block. Confirm a numbered cluster outline and its entry under Cluster Patterns.
4. Select that pattern and choose Adaptive Shape for the first test. Inspect its selected cells and gaps.
5. Use Select and Move (V) to inspect the sheet without creating another cluster. Avoid dragging selected tiles unless you intend to move the group.
6. Save and reopen the Tileset, then check that the cluster and mode remain.

Expected result: the mapping retains the authored cluster. The sheet shows each saved cluster’s outline and number, with the active cluster emphasized.

Choose a Pattern Mode

Mode	Behavior
Adaptive Shape	Adapts artwork as the Scene cluster changes. Exact shapes take priority; a complete 3 × 3 block supplies fallback corners, edges, and center lanes.
Shape Detail	Preserves a local shape when its gaps match and supplies diagonal and concave samples elsewhere.
Repeat Inside	Repeats a multi-tile group through larger interiors. Selection gaps are ignored.

Start with one Adaptive Shape pattern. Add detail or repeated interior patterns only after the basic border works. Preview Color helps identify the mapping in the editor; it does not recolor the source artwork.

Paint and Verify

Open the Scene, choose Tile Mode and Paint, select the Tileset, and enable the matching Auto Tile Mapping option. Paint an isolated cell, a short row, a rectangle, and an L shape. Add a cell at an edge, then erase one from the middle.

Expected result: surrounding cells update to fit the changed cluster. Inspect outer corners, inner corners, single-cell ends, and large interiors. Switch off Auto Tile Mapping when you want ordinary single-tile painting.

Collision and Gameplay Type remain tile metadata. A connected visual border does not establish correct contact geometry. Test the same terrain with the moving Object’s Collider, save, reopen, and inspect the painted map in playtest.

Troubleshooting

If mapping is unavailable, import or create Tileset artwork first and open it inside Myth Engine. If only one picture repeats, check whether mapping is enabled in Scene Paint and whether the selected pattern supplies the missing shape.

If corners are wrong, inspect pattern cell selection, gaps, and mode. If an existing map changes after editing the sheet, inspect tile identity and layout before repainting it. Use Undo for accidental sheet moves and retain the backup before reimporting.

See Tileset Editor, Pixel Editor, and collision.