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authortruebrain <truebrain@openttd.org>2009-01-12 17:11:45 +0000
committertruebrain <truebrain@openttd.org>2009-01-12 17:11:45 +0000
commita3dd7506d377b1434f913bd65c019eed52b64b6e (patch)
treeced1a262eb143ad6e64ec02f4a4c89835c0c32fd /bin/ai/library/pathfinder/road
parent9294f9616866b9778c22076c19b5a32b4f85f788 (diff)
downloadopenttd-a3dd7506d377b1434f913bd65c019eed52b64b6e.tar.xz
(svn r15027) -Merge: tomatos and bananas left to be, here is NoAI for all to see.
NoAI is an API (a framework) to build your own AIs in. See: http://wiki.openttd.org/wiki/index.php/AI:Main_Page With many thanks to: - glx and Rubidium for their syncing, feedback and hard work - Yexo for his feedback, patches, and AIs which tested the system very deep - Morloth for his feedback and patches - TJIP for hosting a challenge which kept NoAI on track - All AI authors for testing our AI API, and all other people who helped in one way or another -Remove: all old AIs and their cheats/hacks
Diffstat (limited to 'bin/ai/library/pathfinder/road')
-rw-r--r--bin/ai/library/pathfinder/road/library.nut12
-rw-r--r--bin/ai/library/pathfinder/road/main.nut363
2 files changed, 375 insertions, 0 deletions
diff --git a/bin/ai/library/pathfinder/road/library.nut b/bin/ai/library/pathfinder/road/library.nut
new file mode 100644
index 000000000..b3c6f1f54
--- /dev/null
+++ b/bin/ai/library/pathfinder/road/library.nut
@@ -0,0 +1,12 @@
+/* $Id$ */
+
+class Road extends AILibrary {
+ function GetAuthor() { return "OpenTTD NoAI Developers Team"; }
+ function GetName() { return "Road"; }
+ function GetDescription() { return "An implementation of a road pathfinder"; }
+ function GetVersion() { return 3; }
+ function GetDate() { return "2008-06-18"; }
+ function CreateInstance() { return "Road"; }
+}
+
+RegisterLibrary(Road());
diff --git a/bin/ai/library/pathfinder/road/main.nut b/bin/ai/library/pathfinder/road/main.nut
new file mode 100644
index 000000000..b33722369
--- /dev/null
+++ b/bin/ai/library/pathfinder/road/main.nut
@@ -0,0 +1,363 @@
+/* $Id$ */
+
+/**
+ * A Road Pathfinder.
+ * This road pathfinder tries to find a buildable / existing route for
+ * road vehicles. You can changes the costs below using for example
+ * roadpf.cost.turn = 30. Note that it's not allowed to change the cost
+ * between consecutive calls to FindPath. You can change the cost before
+ * the first call to FindPath and after FindPath has returned an actual
+ * route. To use only existing roads, set cost.no_existing_road to
+ * cost.max_cost.
+ */
+class Road
+{
+ _aystar_class = import("graph.aystar", "", 4);
+ _max_cost = null; ///< The maximum cost for a route.
+ _cost_tile = null; ///< The cost for a single tile.
+ _cost_no_existing_road = null; ///< The cost that is added to _cost_tile if no road exists yet.
+ _cost_turn = null; ///< The cost that is added to _cost_tile if the direction changes.
+ _cost_slope = null; ///< The extra cost if a road tile is sloped.
+ _cost_bridge_per_tile = null; ///< The cost per tile of a new bridge, this is added to _cost_tile.
+ _cost_tunnel_per_tile = null; ///< The cost per tile of a new tunnel, this is added to _cost_tile.
+ _cost_coast = null; ///< The extra cost for a coast tile.
+ _pathfinder = null; ///< A reference to the used AyStar object.
+ _max_bridge_length = null; ///< The maximum length of a bridge that will be build.
+ _max_tunnel_length = null; ///< The maximum length of a tunnel that will be build.
+
+ cost = null; ///< Used to change the costs.
+ _running = null;
+
+ constructor()
+ {
+ this._max_cost = 10000000;
+ this._cost_tile = 100;
+ this._cost_no_existing_road = 40;
+ this._cost_turn = 100;
+ this._cost_slope = 200;
+ this._cost_bridge_per_tile = 150;
+ this._cost_tunnel_per_tile = 120;
+ this._cost_coast = 20;
+ this._max_bridge_length = 10;
+ this._max_tunnel_length = 20;
+ this._pathfinder = this._aystar_class(this._Cost, this._Estimate, this._Neighbours, this._CheckDirection, this, this, this, this);
+
+ this.cost = this.Cost(this);
+ this._running = false;
+ }
+
+ /**
+ * Initialize a path search between sources and goals.
+ * @param sources The source tiles.
+ * @param goals The target tiles.
+ * @see AyStar::InitializePath()
+ */
+ function InitializePath(sources, goals) {
+ local nsources = [];
+
+ foreach (node in sources) {
+ nsources.push([node, 0xFF]);
+ }
+ this._pathfinder.InitializePath(nsources, goals);
+ }
+
+ /**
+ * Try to find the path as indicated with InitializePath with the lowest cost.
+ * @param iterations After how many iterations it should abort for a moment.
+ * This value should either be -1 for infinite, or > 0. Any other value
+ * aborts immediatly and will never find a path.
+ * @return A route if one was found, or false if the amount of iterations was
+ * reached, or null if no path was found.
+ * You can call this function over and over as long as it returns false,
+ * which is an indication it is not yet done looking for a route.
+ * @see AyStar::FindPath()
+ */
+ function FindPath(iterations);
+};
+
+class Road.Cost
+{
+ _main = null;
+
+ function _set(idx, val)
+ {
+ if (this._main._running) throw("You are not allowed to change parameters of a running pathfinder.");
+
+ switch (idx) {
+ case "max_cost": this._main._max_cost = val; break;
+ case "tile": this._main._cost_tile = val; break;
+ case "no_existing_road": this._main._cost_no_existing_road = val; break;
+ case "turn": this._main._cost_turn = val; break;
+ case "slope": this._main._cost_slope = val; break;
+ case "bridge_per_tile": this._main._cost_bridge_per_tile = val; break;
+ case "tunnel_per_tile": this._main._cost_tunnel_per_tile = val; break;
+ case "coast": this._main._cost_coast = val; break;
+ case "max_bridge_length": this._main._max_bridge_length = val; break;
+ case "max_tunnel_length": this._main._max_tunnel_length = val; break;
+ default: throw("the index '" + idx + "' does not exist");
+ }
+
+ return val;
+ }
+
+ function _get(idx)
+ {
+ switch (idx) {
+ case "max_cost": return this._main._max_cost;
+ case "tile": return this._main._cost_tile;
+ case "no_existing_road": return this._main._cost_no_existing_road;
+ case "turn": return this._main._cost_turn;
+ case "slope": return this._main._cost_slope;
+ case "bridge_per_tile": return this._main._cost_bridge_per_tile;
+ case "tunnel_per_tile": return this._main._cost_tunnel_per_tile;
+ case "coast": return this._main._cost_coast;
+ case "max_bridge_length": return this._main._max_bridge_length;
+ case "max_tunnel_length": return this._main._max_tunnel_length;
+ default: throw("the index '" + idx + "' does not exist");
+ }
+ }
+
+ constructor(main)
+ {
+ this._main = main;
+ }
+};
+
+function Road::FindPath(iterations)
+{
+ local test_mode = AITestMode();
+ local ret = this._pathfinder.FindPath(iterations);
+ this._running = (ret == false) ? true : false;
+ return ret;
+}
+
+function Road::_GetBridgeNumSlopes(end_a, end_b)
+{
+ local slopes = 0;
+ local direction = (end_b - end_a) / AIMap.DistanceManhattan(end_a, end_b);
+ local slope = AITile.GetSlope(end_a);
+ if (!((slope == AITile.SLOPE_NE && direction == 1) || (slope == AITile.SLOPE_SE && direction == -AIMap.GetMapSizeX()) ||
+ (slope == AITile.SLOPE_SW && direction == -1) || (slope == AITile.SLOPE_NW && direction == AIMap.GetMapSizeX()) ||
+ slope == AITile.SLOPE_N || slope == AITile.SLOPE_E || slope == AITile.SLOPE_S || slope == AITile.SLOPE_W)) {
+ slopes++;
+ }
+
+ local slope = AITile.GetSlope(end_b);
+ direction = -direction;
+ if (!((slope == AITile.SLOPE_NE && direction == 1) || (slope == AITile.SLOPE_SE && direction == -AIMap.GetMapSizeX()) ||
+ (slope == AITile.SLOPE_SW && direction == -1) || (slope == AITile.SLOPE_NW && direction == AIMap.GetMapSizeX()) ||
+ slope == AITile.SLOPE_N || slope == AITile.SLOPE_E || slope == AITile.SLOPE_S || slope == AITile.SLOPE_W)) {
+ slopes++;
+ }
+ return slopes;
+}
+
+function Road::_Cost(path, new_tile, new_direction, self)
+{
+ /* path == null means this is the first node of a path, so the cost is 0. */
+ if (path == null) return 0;
+
+ local prev_tile = path.GetTile();
+
+ /* If the new tile is a bridge / tunnel tile, check whether we came from the other
+ * end of the bridge / tunnel or if we just entered the bridge / tunnel. */
+ if (AIBridge.IsBridgeTile(new_tile)) {
+ if (AIBridge.GetOtherBridgeEnd(new_tile) != prev_tile) return path.GetCost() + self._cost_tile;
+ return path.GetCost() + AIMap.DistanceManhattan(new_tile, prev_tile) * self._cost_tile + self._GetBridgeNumSlopes(new_tile, prev_tile) * self._cost_slope;
+ }
+ if (AITunnel.IsTunnelTile(new_tile)) {
+ if (AITunnel.GetOtherTunnelEnd(new_tile) != prev_tile) return path.GetCost() + self._cost_tile;
+ return path.GetCost() + AIMap.DistanceManhattan(new_tile, prev_tile) * self._cost_tile;
+ }
+
+ /* If the two tiles are more then 1 tile apart, the pathfinder wants a bridge or tunnel
+ * to be build. It isn't an existing bridge / tunnel, as that case is already handled. */
+ if (AIMap.DistanceManhattan(new_tile, prev_tile) > 1) {
+ /* Check if we should build a bridge or a tunnel. */
+ if (AITunnel.GetOtherTunnelEnd(new_tile) == prev_tile) {
+ return path.GetCost() + AIMap.DistanceManhattan(new_tile, prev_tile) * (self._cost_tile + self._cost_tunnel_per_tile);
+ } else {
+ return path.GetCost() + AIMap.DistanceManhattan(new_tile, prev_tile) * (self._cost_tile + self._cost_bridge_per_tile) + self._GetBridgeNumSlopes(new_tile, prev_tile) * self._cost_slope;
+ }
+ }
+
+ /* Check for a turn. We do this by substracting the TileID of the current node from
+ * the TileID of the previous node and comparing that to the difference between the
+ * previous node and the node before that. */
+ local cost = self._cost_tile;
+ if (path.GetParent() != null && (prev_tile - path.GetParent().GetTile()) != (new_tile - prev_tile) &&
+ AIMap.DistanceManhattan(path.GetParent().GetTile(), prev_tile) == 1) {
+ cost += self._cost_turn;
+ }
+
+ /* Check if the new tile is a coast tile. */
+ if (AITile.IsCoastTile(new_tile)) {
+ cost += self._cost_coast;
+ }
+
+ /* Check if the last tile was sloped. */
+ if (path.GetParent() != null && !AIBridge.IsBridgeTile(prev_tile) && !AITunnel.IsTunnelTile(prev_tile) &&
+ self._IsSlopedRoad(path.GetParent().GetTile(), prev_tile, new_tile)) {
+ cost += self._cost_slope;
+ }
+
+ if (!AIRoad.AreRoadTilesConnected(prev_tile, new_tile)) {
+ cost += self._cost_no_existing_road;
+ }
+
+ return path.GetCost() + cost;
+}
+
+function Road::_Estimate(cur_tile, cur_direction, goal_tiles, self)
+{
+ local min_cost = self._max_cost;
+ /* As estimate we multiply the lowest possible cost for a single tile with
+ * with the minimum number of tiles we need to traverse. */
+ foreach (tile in goal_tiles) {
+ min_cost = min(AIMap.DistanceManhattan(cur_tile, tile) * self._cost_tile, min_cost);
+ }
+ return min_cost;
+}
+
+function Road::_Neighbours(path, cur_node, self)
+{
+ /* self._max_cost is the maximum path cost, if we go over it, the path isn't valid. */
+ if (path.GetCost() >= self._max_cost) return [];
+ local tiles = [];
+
+ /* Check if the current tile is part of a bridge or tunnel. */
+ if ((AIBridge.IsBridgeTile(cur_node) || AITunnel.IsTunnelTile(cur_node)) &&
+ AITile.HasTransportType(cur_node, AITile.TRANSPORT_ROAD)) {
+ local other_end = AIBridge.IsBridgeTile(cur_node) ? AIBridge.GetOtherBridgeEnd(cur_node) : AITunnel.GetOtherTunnelEnd(cur_node);
+ local next_tile = cur_node + (cur_node - other_end) / AIMap.DistanceManhattan(cur_node, other_end);
+ if (AIRoad.AreRoadTilesConnected(cur_node, next_tile) || AITile.IsBuildable(next_tile) || AIRoad.IsRoadTile(next_tile)) {
+ tiles.push([next_tile, self._GetDirection(cur_node, next_tile, false)]);
+ }
+ /* The other end of the bridge / tunnel is a neighbour. */
+ tiles.push([other_end, self._GetDirection(next_tile, cur_node, true) << 4]);
+ } else if (path.GetParent() != null && AIMap.DistanceManhattan(cur_node, path.GetParent().GetTile()) > 1) {
+ local other_end = path.GetParent().GetTile();
+ local next_tile = cur_node + (cur_node - other_end) / AIMap.DistanceManhattan(cur_node, other_end);
+ if (AIRoad.AreRoadTilesConnected(cur_node, next_tile) || AIRoad.BuildRoad(cur_node, next_tile)) {
+ tiles.push([next_tile, self._GetDirection(cur_node, next_tile, false)]);
+ }
+ } else {
+ local offsets = [AIMap.GetTileIndex(0, 1), AIMap.GetTileIndex(0, -1),
+ AIMap.GetTileIndex(1, 0), AIMap.GetTileIndex(-1, 0)];
+ /* Check all tiles adjacent to the current tile. */
+ foreach (offset in offsets) {
+ local next_tile = cur_node + offset;
+ /* We add them to the to the neighbours-list if one of the following applies:
+ * 1) There already is a connections between the current tile and the next tile.
+ * 2) We can build a road to the next tile.
+ * 3) The next tile is the entrance of a tunnel / bridge in the correct direction. */
+ if (AIRoad.AreRoadTilesConnected(cur_node, next_tile)) {
+ tiles.push([next_tile, self._GetDirection(cur_node, next_tile, false)]);
+ } else if ((AITile.IsBuildable(next_tile) || AIRoad.IsRoadTile(next_tile)) &&
+ (path.GetParent() == null || AIRoad.CanBuildConnectedRoadPartsHere(cur_node, path.GetParent().GetTile(), next_tile)) &&
+ AIRoad.BuildRoad(cur_node, next_tile)) {
+ tiles.push([next_tile, self._GetDirection(cur_node, next_tile, false)]);
+ } else if (self._CheckTunnelBridge(cur_node, next_tile)) {
+ tiles.push([next_tile, self._GetDirection(cur_node, next_tile, false)]);
+ }
+ }
+ if (path.GetParent() != null) {
+ local bridges = self._GetTunnelsBridges(path.GetParent().GetTile(), cur_node, self._GetDirection(path.GetParent().GetTile(), cur_node, true) << 4);
+ foreach (tile in bridges) {
+ tiles.push(tile);
+ }
+ }
+ }
+ return tiles;
+}
+
+function Road::_CheckDirection(tile, existing_direction, new_direction, self)
+{
+ return false;
+}
+
+function Road::_GetDirection(from, to, is_bridge)
+{
+ if (!is_bridge && AITile.GetSlope(to) == AITile.SLOPE_FLAT) return 0xFF;
+ if (from - to == 1) return 1;
+ if (from - to == -1) return 2;
+ if (from - to == AIMap.GetMapSizeX()) return 4;
+ if (from - to == -AIMap.GetMapSizeX()) return 8;
+}
+
+/**
+ * Get a list of all bridges and tunnels that can be build from the
+ * current tile. Bridges will only be build starting on non-flat tiles
+ * for performance reasons. Tunnels will only be build if no terraforming
+ * is needed on both ends.
+ */
+function Road::_GetTunnelsBridges(last_node, cur_node, bridge_dir)
+{
+ local slope = AITile.GetSlope(cur_node);
+ if (slope == AITile.SLOPE_FLAT) return [];
+ local tiles = [];
+
+ for (local i = 2; i < this._max_bridge_length; i++) {
+ local bridge_list = AIBridgeList_Length(i + 1);
+ local target = cur_node + i * (cur_node - last_node);
+ if (!bridge_list.IsEmpty() && AIBridge.BuildBridge(AIVehicle.VEHICLE_ROAD, bridge_list.Begin(), cur_node, target)) {
+ tiles.push([target, bridge_dir]);
+ }
+ }
+
+ if (slope != AITile.SLOPE_SW && slope != AITile.SLOPE_NW && slope != AITile.SLOPE_SE && slope != AITile.SLOPE_NE) return tiles;
+ local other_tunnel_end = AITunnel.GetOtherTunnelEnd(cur_node);
+ if (!AIMap.IsValidTile(other_tunnel_end)) return tiles;
+
+ local tunnel_length = AIMap.DistanceManhattan(cur_node, other_tunnel_end);
+ local prev_tile = cur_node + (cur_node - other_tunnel_end) / tunnel_length;
+ if (AITunnel.GetOtherTunnelEnd(other_tunnel_end) == cur_node && tunnel_length >= 2 &&
+ prev_tile == last_node && tunnel_length < _max_tunnel_length && AITunnel.BuildTunnel(AIVehicle.VEHICLE_ROAD, cur_node)) {
+ tiles.push([other_tunnel_end, bridge_dir]);
+ }
+ return tiles;
+}
+
+function Road::_IsSlopedRoad(start, middle, end)
+{
+ local NW = 0; //Set to true if we want to build a road to / from the north-west
+ local NE = 0; //Set to true if we want to build a road to / from the north-east
+ local SW = 0; //Set to true if we want to build a road to / from the south-west
+ local SE = 0; //Set to true if we want to build a road to / from the south-east
+
+ if (middle - AIMap.GetMapSizeX() == start || middle - AIMap.GetMapSizeX() == end) NW = 1;
+ if (middle - 1 == start || middle - 1 == end) NE = 1;
+ if (middle + AIMap.GetMapSizeX() == start || middle + AIMap.GetMapSizeX() == end) SE = 1;
+ if (middle + 1 == start || middle + 1 == end) SW = 1;
+
+ /* If there is a turn in the current tile, it can't be sloped. */
+ if ((NW || SE) && (NE || SW)) return false;
+
+ local slope = AITile.GetSlope(middle);
+ /* A road on a steep slope is always sloped. */
+ if (AITile.IsSteepSlope(slope)) return true;
+
+ /* If only one corner is raised, the road is sloped. */
+ if (slope == AITile.SLOPE_N || slope == AITile.SLOPE_W) return true;
+ if (slope == AITile.SLOPE_S || slope == AITile.SLOPE_E) return true;
+
+ if (NW && (slope == AITile.SLOPE_NW || slope == AITile.SLOPE_SE)) return true;
+ if (NE && (slope == AITile.SLOPE_NE || slope == AITile.SLOPE_SW)) return true;
+
+ return false;
+}
+
+function Road::_CheckTunnelBridge(current_tile, new_tile)
+{
+ if (!AIBridge.IsBridgeTile(new_tile) && !AITunnel.IsTunnelTile(new_tile)) return false;
+ local dir = new_tile - current_tile;
+ local other_end = AIBridge.IsBridgeTile(new_tile) ? AIBridge.GetOtherBridgeEnd(new_tile) : AITunnel.GetOtherTunnelEnd(new_tile);
+ local dir2 = other_end - new_tile;
+ if ((dir < 0 && dir2 > 0) || (dir > 0 && dir2 < 0)) return false;
+ dir = abs(dir);
+ dir2 = abs(dir2);
+ if ((dir >= AIMap.GetMapSizeX() && dir2 < AIMap.GetMapSizeX()) ||
+ (dir < AIMap.GetMapSizeX() && dir2 >= AIMap.GetMapSizeX())) return false;
+
+ return true;
+}