Factorio Forums

Posted: **Sun Feb 15, 2026 11:02 am**

What

Please allow for calling LuaSurface::request_path with a new argument preferred_tiles. This could be in the form

-- Array of arrays of tile prototype names.  
preferred_tiles = {
	-- All tiles listed in an array have the same
	{  "concrete", "hazard-concrete-left", "hazard-concrete-right", },
	{ "stone-path" },
	...
}

-- Map: tile_name --> priority
preferred_tiles = {
	["concrete"] = 1,
	["hazard-concrete-left"] = 1,
	["hazard-concrete-right"] = 1,
	["stone-path"] = 2,
	...
}

When searching for a path, try to path over preferred tiles even if the path to goal becomes a bit longer.

Use case

My mod Autodrive makes use of LuaSurface::request_path() to navigate vehicles from their current position to another destination. What I've often observed is that vehicles move slowly over unfavourable terrain while, say, a concrete road leads in roughly the same direction just a few tiles away from the calculated path. Being able to optionally (!) specify a list of tile-prototype names to be preferred during pathing would allow players to see their carefully laid out roads actually be used by automatically driving vehicles.

Factorio Forums

Allow for preferred tiles in LuaSurface::request_path

Allow for preferred tiles in LuaSurface::request_path

What

Use case