Tile Map Editor

The Tile Map Editor paints the tiles of a Tile Map object. Open it by double-clicking a Tile Map object in the Hierarchy; the editor always follows the selected Tile Map object.

Toolbar

Control	What it does
Tileset	Chooses the image that holds the tiles (click the browse icon to open the file dialog).
Tile Width / Tile Height	Size of a single cell in the tileset image.
Columns / Rows	Grid size of the map (number of cells).
Paint / Erase / Fill / Pick Tile	The four painting tools.
Zoom Out / Zoom In / Fit	Scales the canvas; Fit shows the whole map.
Detach	Floats the panel in its own window; click the button again or close the window to dock it back.

The status line under the toolbar shows the map size and how many tiles the tileset offers; if it says the tileset cannot fit whole tiles, the tile size does not match the cell size of the source image.

Layers

The layer bar under the toolbar manages the map layers:

Control	What it does
Layer list	Chooses the layer that is edited and painted on.
Add / Delete / Rename	Manages the layers; the map always keeps at least one.
Eye icon	Shows or hides the current layer.
Collision	Marks the layer as a collision layer: every cell with a tile of that layer is solid in the game.

Layers are drawn from the bottom upwards, so an upper layer covers the one below. Use one layer for the ground, one for decorations, and a separate layer for obstacles the player must not walk through.