Export tileset

Export Tileset.lua

if TilesetMode == nil then return app.alert "Use Aseprite v1.3"  end

local lay = app.activeLayer
if not lay.isTilemap then return app.alert "No active tilemap layer" end

local tileset = lay.tileset

local dlg = Dialog("Export Tileset")
dlg:file{ id="file", label="Export to File:", save=true, focus=true,
          filename=app.fs.joinPath(app.fs.filePath(lay.sprite.filename),
                                   lay.name .. ".png") }
   :label{ label="# Tiles", text=tostring(#tileset) }
   :separator()
   :button{ text="&Export", focus=true, id="ok" }
   :button{ text="&Cancel" }
   :show()

local data = dlg.data
if data.ok then
  local spec = lay.sprite.spec
  local grid = tileset.grid
  local size = grid.tileSize
  spec.width = size.width
  spec.height = size.height * #tileset
  local image = Image(spec)
  image:clear()
  for i = 0,#tileset-1 do
    local tile = tileset:getTile(i)
    image:drawImage(tile, 0, i*size.height)
  end
  image:saveAs(data.file)

  -- Open exported file?
  --app.open(data.file)
end

Useful script, thanks! But it exports images with indexed colors as black-white.