move apis into rom/modules/main for shell compatibility

sys/modules/opus/jumper/core/path.lua

@@ -0,0 +1,67 @@
+--- The Path class.
+-- The `path` class is a structure which represents a path (ordered set of nodes) from a start location to a goal.
+-- An instance from this class would be a result of a request addressed to `Pathfinder:getPath`.
+--
+-- This module is internally used by the library on purpose.
+-- It should normally not be used explicitely, yet it remains fully accessible.
+--
+
+if (...) then
+
+	local t_remove = table.remove
+
+	local Path = {}
+	Path.__index = Path
+
+	function Path:new()
+		return setmetatable({_nodes = {}}, Path)
+	end
+
+	--- Iterates on each single `node` along a `path`. At each step of iteration,
+	-- returns the `node` plus a count value. Aliased as @{Path:nodes}
+	-- @usage
+	-- for node, count in p:iter() do
+	--   ...
+	-- end
+	function Path:nodes()
+		local i = 1
+		return function()
+			if self._nodes[i] then
+				i = i+1
+				return self._nodes[i-1],i-1
+			end
+		end
+	end
+
+	--- `Path` compression modifier. Given a `path`, eliminates useless nodes to return a lighter `path`
+	-- consisting of straight moves. Does the opposite of @{Path:fill}
+	-- @class function
+	-- @treturn path self (the calling `path` itself, can be chained)
+	-- @see Path:fill
+	-- @usage p:filter()
+	function Path:filter()
+		local i = 2
+		local xi,yi,zi,dx,dy,dz, olddx, olddy, olddz
+		xi,yi,zi = self._nodes[i].x, self._nodes[i].y, self._nodes[i].z
+		dx, dy,dz = xi - self._nodes[i-1].x, yi-self._nodes[i-1].y, zi-self._nodes[i-1].z
+		while true do
+			olddx, olddy, olddz = dx, dy, dz
+			if self._nodes[i+1] then
+				i = i+1
+				xi, yi, zi = self._nodes[i].x, self._nodes[i].y, self._nodes[i].z
+				dx, dy, dz = xi - self._nodes[i-1].x, yi - self._nodes[i-1].y, zi - self._nodes[i-1].z
+				if olddx == dx and olddy == dy and olddz == dz then
+					t_remove(self._nodes, i-1)
+					i = i - 1
+				end
+			else break end
+		end
+		return self
+	end
+
+	return setmetatable(Path,
+		{__call = function(_,...)
+			return Path:new(...)
+		end
+	})
+end