real autowalking

* smart autowalking using A* path finding algorithm

modules/game/widgets/uigamemap.lua

@@ -63,32 +63,11 @@ function UIGameMap:onMouseRelease(mousePosition, mouseButton)
   if GameInterface.processMouseAction(mousePosition, mouseButton, nil, tile:getTopLookThing(), tile:getTopUseThing(), tile:getTopCreature(), tile:getTopMultiUseThing()) then
     return true
   elseif mouseButton == MouseLeftButton then
-    local fromPos = g_game.getLocalPlayer():getPosition()
-    local toPos = tile:getPosition()
-    if fromPos.z ~= toPos.z then
+    local dirs = g_map.findPath(g_game.getLocalPlayer():getPosition(), tile:getPosition(), 255)
+    if #dirs == 0 then
       TextMessage.displayStatus('There is no way.')
       return true
     end
-
-    -- simple and stupid pathfinding algorithm
-    local dirs = {}
-    local pathPos = fromPos
-    while pathPos.x ~= toPos.x or pathPos.y ~= toPos.y do
-      if pathPos.x < toPos.x then
-        pathPos.x = pathPos.x + 1
-        table.insert(dirs, East)
-      elseif pathPos.x > toPos.x then
-        pathPos.x = pathPos.x - 1
-        table.insert(dirs, West)
-      elseif pathPos.y < toPos.y then
-        pathPos.y = pathPos.y + 1
-        table.insert(dirs, South)
-      else --if pathPos.y > toPos.y then
-        pathPos.y = pathPos.y - 1
-        table.insert(dirs, North)
-      end
-    end
-
     g_game.autoWalk(dirs)
     return true
   end

src/otclient/core/game.cpp

@@ -372,15 +372,18 @@ void Game::walk(Otc::Direction direction)
     forceWalk(direction);
 }
 
-void Game::autoWalk(const std::vector<Otc::Direction>& dir)
+void Game::autoWalk(const std::vector<Otc::Direction>& dirs)
 {
     if(!canPerformGameAction())
         return;
 
+    if(dirs.size() >= 255)
+        return;
+
     if(isFollowing())
         cancelFollow();
 
-    m_protocolGame->sendAutoWalk(dir);
+    m_protocolGame->sendAutoWalk(dirs);
 }
 
 void Game::forceWalk(Otc::Direction direction)

src/otclient/core/game.h

@@ -123,7 +123,7 @@ public:
 
     // walk related
     void walk(Otc::Direction direction);
-    void autoWalk(const std::vector<Otc::Direction>& dir);
+    void autoWalk(const std::vector<Otc::Direction>& dirs);
     void forceWalk(Otc::Direction direction);
     void turn(Otc::Direction direction);
     void stop();

src/otclient/core/map.cpp

@@ -411,3 +411,111 @@ int Map::getLastAwareFloor()
     else
         return Otc::SEA_FLOOR;
 }
+
+// pathfinding using A* search algorithm
+// as described in http://en.wikipedia.org/wiki/A*_search_algorithm
+std::vector<Otc::Direction> Map::findPath(const Position& startPos, const Position& goalPos, int maxSteps)
+{
+    struct Node {
+        Node(const Position& pos) : cost(0), totalCost(0), steps(0), pos(pos), prev(nullptr), dir(Otc::InvalidDirection), evaluated(false) { }
+        bool operator<(const Node& other) const { return  totalCost < other.totalCost; }
+        float cost;
+        float totalCost;
+        int steps;
+        Position pos;
+        Node *prev;
+        Otc::Direction dir;
+        bool evaluated;
+    };
+
+    struct LessNode : std::binary_function<Node*, Node*, bool> {
+        bool operator()(Node* a, Node* b) const {
+            return b->totalCost < a->totalCost;
+        }
+    };
+
+    std::vector<Otc::Direction> dirs;
+
+    if(startPos == goalPos || startPos.z != goalPos.z || startPos.distance(goalPos) > maxSteps) {
+        return dirs;
+    }
+
+    auto estimateCost = [=](const Position& pos) { return pos.distance(goalPos); };
+    std::unordered_map<Position, Node*, PositionHasher> nodes;
+    std::priority_queue<Node*, std::vector<Node*>, LessNode> searchList;
+
+    Node *currentNode = new Node(startPos);
+    currentNode->pos = startPos;
+    Node *foundNode = nullptr;
+    while(currentNode && currentNode->steps < maxSteps) {
+        if(currentNode->pos == goalPos && (!foundNode || currentNode->cost < foundNode->cost))
+            foundNode = currentNode;
+
+        if(foundNode && currentNode->totalCost >= foundNode->cost)
+            break;
+
+        for(int i=-1;i<=1;++i) {
+            for(int j=-1;j<=1;++j) {
+                if(i == 0 && j == 0)
+                    continue;
+
+                Position neighborPos = currentNode->pos.translated(i, j);
+                const TilePtr& tile = getTile(neighborPos);
+                if(!tile || !tile->isWalkable())
+                    continue;
+
+                float walkFactor;
+                Otc::Direction walkDir = currentNode->pos.getDirectionFromPosition(neighborPos);
+                if(walkDir >= Otc::NorthEast)
+                    walkFactor = 3.0f;
+                else
+                    walkFactor = 1.0f;
+
+                float cost = currentNode->cost + (tile->getGroundSpeed() * walkFactor) / 100.0f;
+
+                Node *neighborNode;
+                if(nodes.find(neighborPos) == nodes.end()) {
+                    neighborNode = new Node(neighborPos);
+                    nodes[neighborPos] = neighborNode;
+                } else {
+                    neighborNode = nodes[neighborPos];
+                    if(neighborNode->cost < cost)
+                        continue;
+                }
+
+                neighborNode->prev = currentNode;
+                neighborNode->cost = cost;
+                neighborNode->steps = currentNode->steps + 1;
+                neighborNode->totalCost = neighborNode->cost + estimateCost(neighborPos);
+                neighborNode->dir = walkDir;
+                neighborNode->evaluated = false;
+                searchList.push(neighborNode);
+            }
+        }
+
+        currentNode->evaluated = true;
+        currentNode = nullptr;
+        while(searchList.size() > 0 && !currentNode) {
+            Node *node = searchList.top();
+            searchList.pop();
+
+            if(!node->evaluated)
+                currentNode = node;
+        }
+    }
+
+    if(foundNode) {
+        currentNode = foundNode;
+        while(currentNode) {
+            dirs.push_back(currentNode->dir);
+            currentNode = currentNode->prev;
+        }
+        dirs.pop_back();
+        std::reverse(dirs.begin(), dirs.end());
+    }
+
+    for(auto it : nodes)
+        delete it.second;
+
+    return dirs;
+}

src/otclient/core/map.h

@@ -76,6 +76,8 @@ public:
     std::vector<AnimatedTextPtr> getAnimatedTexts() { return m_animatedTexts; }
     std::vector<StaticTextPtr> getStaticTexts() { return m_staticTexts; }
 
+    std::vector<Otc::Direction> findPath(const Position& start, const Position& goal, int maxSteps);
+
 private:
     std::unordered_map<Position, TilePtr, PositionHasher> m_tiles;
     std::map<uint32, CreaturePtr> m_knownCreatures;

src/otclient/core/mapview.cpp

@@ -425,6 +425,7 @@ void MapView::setVisibleDimension(const Size& visibleDimension)
     }
 
     Point virtualCenterOffset = (drawDimension/2 - Size(1,1)).toPoint();
+    Point visibleCenterOffset = virtualCenterOffset;
 
     ViewRange viewRange;
     if(tileSize >= 32 && visibleDimension.area() <= NEAR_VIEW_AREA)
@@ -446,6 +447,7 @@ void MapView::setVisibleDimension(const Size& visibleDimension)
     bool mustUpdate = (m_drawDimension != drawDimension ||
                        m_viewRange != viewRange ||
                        m_virtualCenterOffset != virtualCenterOffset ||
+                       m_visibleCenterOffset != visibleCenterOffset ||
                        m_tileSize != tileSize);
 
     m_visibleDimension = visibleDimension;
@@ -453,6 +455,7 @@ void MapView::setVisibleDimension(const Size& visibleDimension)
     m_tileSize = tileSize;
     m_viewRange = viewRange;
     m_virtualCenterOffset = virtualCenterOffset;
+    m_visibleCenterOffset = visibleCenterOffset;
 
     if(mustUpdate)
         requestVisibleTilesCacheUpdate();
@@ -550,7 +553,7 @@ TilePtr MapView::getTile(const Point& mousePos, const Rect& mapRect)
         tilePos2D += m_followingCreature->getWalkOffset() * scaleFactor;
     tilePos2D /= m_tileSize;
 
-    Position tilePos = Position(1 + (int)tilePos2D.x - m_virtualCenterOffset.x, 1 + (int)tilePos2D.y - m_virtualCenterOffset.y, 0) + cameraPosition;
+    Position tilePos = Position(1 + (int)tilePos2D.x - m_visibleCenterOffset.x, 1 + (int)tilePos2D.y - m_visibleCenterOffset.y, 0) + cameraPosition;
     if(!tilePos.isValid())
         return nullptr;
 

src/otclient/core/mapview.h

@@ -100,6 +100,7 @@ private:
     Size m_drawDimension;
     Size m_visibleDimension;
     Point m_virtualCenterOffset;
+    Point m_visibleCenterOffset;
     Position m_customCameraPosition;
     Boolean<true> m_mustUpdateVisibleTilesCache;
     Boolean<true> m_mustDrawVisibleTilesCache;

src/otclient/luafunctions.cpp

@@ -75,6 +75,7 @@ void OTClient::registerLuaFunctions()
     g_lua.bindClassStaticFunction("g_map", "getCreatureById", std::bind(&Map::getCreatureById, &g_map, _1));
     g_lua.bindClassStaticFunction("g_map", "removeCreatureById", std::bind(&Map::removeCreatureById, &g_map, _1));
     g_lua.bindClassStaticFunction("g_map", "getSpectators", std::bind(&Map::getSpectators, &g_map, _1, _2));
+    g_lua.bindClassStaticFunction("g_map", "findPath", std::bind(&Map::findPath, &g_map, _1, _2, _3));
 
     g_lua.registerStaticClass("g_game");
     g_lua.bindClassStaticFunction("g_game", "loginWorld", std::bind(&Game::loginWorld, &g_game, _1, _2, _3, _4, _5));

src/otclient/util/position.h

@@ -151,6 +151,8 @@ public:
     }
 
     bool isValid() const { return !(x == 65535 && y == 65535 && z == 255); }
+    float distance(const Position& pos) const { return sqrt(pow((pos.x - x), 2) + pow((pos.y - y), 2)); }
+    int manhattanDistance(const Position& pos) const { return std::abs(pos.x - x) + std::abs(pos.y - y); }
 
     void translate(int dx, int dy, short dz = 0) { x += dx; y += dy; z += dz; }
     Position translated(int dx, int dy, short dz = 0) const { Position pos = *this; pos.x += dx; pos.y += dy; pos.z += dz; return pos; }