Update gps.lua

Author: T-MaxWiese-T

[gameplay]/gps/gps.lua

@@ -1,19 +1,43 @@
 local floor = math.floor
 
+local file = fileOpen("vehiclenodes.json", true)
+local size = fileGetSize(file)
+local rawData = fromJSON(fileRead(file, size))
+fileClose(file)
+
+-- Since the JSON structure is wrapped inside an array [{...}], extract the first element!
+vehicleNodes = {}
+if rawData then
+	if rawData[1] then
+		vehicleNodes = rawData[1]
+	else
+		vehicleNodes = rawData
+	end
+end
+
+outputDebugString("GPS: " .. (localPlayer and "Client" or "Server") .. " database initialized successfully!")
+
 local function getAreaID(x, y)
 	return floor((y + 3000)/750)*8 + floor((x + 3000)/750)
 end
 
 local function getNodeByID(db, nodeID)
 	local areaID = floor(nodeID / 65536)
-	return db[areaID][nodeID]
+	local area = db[areaID] or db[tostring(areaID)]
+	if not area then return false end
+	return area[nodeID] or area[tostring(nodeID)]
 end
 
 local function findNodeClosestToPoint(db, x, y, z)
 	local areaID = getAreaID(x, y)
+	
+	-- Fallback lookup for string-indexed areas from client-side JSON decoding
+	local nodesToSearch = db[areaID] or db[tostring(areaID)]
+	if not nodesToSearch then return false end
+	
 	local minDist, minNode
 	local nodeX, nodeY, dist
-	for id,node in pairs(db[areaID]) do
+	for id,node in pairs(nodesToSearch) do
 		nodeX, nodeY = node.x, node.y
 		dist = (x - nodeX)*(x - nodeX) + (y - nodeY)*(y - nodeY)
 		if not minDist or dist < minDist then
@@ -25,6 +49,7 @@ local function findNodeClosestToPoint(db, x, y, z)
 end
 
 local function calculatePath(db, nodeFrom, nodeTo)
+	if not nodeFrom or not nodeTo then return false end
 	local next = next
 
 	local g = { [nodeFrom] = 0 }		-- { node = g }
@@ -61,16 +86,17 @@ local function calculatePath(db, nodeFrom, nodeTo)
 			break
 		end
 
-		local successors = {}
 		for id,distance in pairs(current.neighbours) do
 			local successor = getNodeByID(db, id)
-			local successor_g = g[current] + distance*distance
-			if not g[successor] or g[successor] > successor_g then
-				setmetatable(successor, nodeMT)
+			if successor then
+				local successor_g = g[current] + distance*distance
+				if not g[successor] or g[successor] > successor_g then
+					setmetatable(successor, nodeMT)
 
-				g[successor] = successor_g
-				openheap:insertvalue(successor)
-				parent[successor] = current
+					g[successor] = successor_g
+					openheap:insertvalue(successor)
+					parent[successor] = current
+				end
 			end
 		end
 	end