Add api function to find nearest area

api.lua

@@ -1,4 +1,46 @@
 
+-- Temporary compatibility function - see minetest PR#1180
+if not vector.interpolate then
+	vector.interpolate = function(pos1, pos2)
+		return {x = pos1.x + (pos2.x - pos1.x) * factor,
+		        y = pos1.y + (pos2.y - pos1.y) * factor,
+			z = pos1.z + (pos2.z - pos1.z) * factor}
+		end
+end
+
+
+-- Returns the nearest area to the given position, optionally checking only
+-- areas matching a given pattern (which is a lua regex). The pattern will
+-- be amended to make it case-insensitive.
+-- Returns nil if nothing could be found, otherwise the area and the
+-- distance to it.
+-- maxdist is the maximum distance at which to search.
+function areas:findNearestArea(pos, pattern, maxdist)
+
+	local nearest, nearestdist
+	if pattern then
+		-- Make the pattern case-insensitive...
+		pattern = pattern:gsub("(%%?)(.)", function(percent, letter)
+			if percent ~= "" or not letter:match("%a") then
+				return percent .. letter
+			else
+				return string.format("[%s%s]", letter:lower(), letter:upper())
+			end
+		end)
+	end
+	for id, area in pairs(self.areas) do
+		if (not pattern) or string.find(area.name, pattern) then
+			local centre = vector.interpolate(area.pos1, area.pos2, 0.5)
+			local dist = vector.distance(pos, centre)
+			if ((not nearestdist) or dist < nearestdist) and ((not maxdist) or dist <= maxdist) then
+				nearest = area
+				nearestdist = dist
+			end
+		end
+	end
+	return nearest, nearestdist
+end
+
 -- Returns a list of areas that include the provided position
 function areas:getAreasAtPos(pos)
 	local a = {}