Action List

if( useAStar )
{
    if (newRequest)
    {
        if (m_straightline)
        {
            int curR, curC; //current row and column
            D3DXVECTOR3 cur = m_owner->GetBody().GetPos(); //get position of pathfinder
            g_terrain.GetRowColumn( &cur, &curR, &curC );  //translate pos to row/col
            //optimize for straight path
            if (StraightLineTest(curR, curC, r, c))
            {
                m_waypointList.clear();
                D3DXVECTOR3 spot = g_terrain.GetCoordinates( r, c );
                m_waypointList.push_back( spot );
                return true;
            }
        }

        //reset existing search
        astar->OpenList.clear();
        astar->nodeDataArray.resize(g_terrain.GetWidth() * g_terrain.GetWidth());
        astar->InitNodeArray(g_terrain.GetWidth());

        int curR, curC; //current row and column
        D3DXVECTOR3 cur = m_owner->GetBody().GetPos(); //get position of pathfinder
        g_terrain.GetRowColumn( &cur, &curR, &curC );  //translate pos to row/col

        //Push Start Node onto the Open List
        //set up starting node
        astar->nodeDataArray[curR * g_terrain.GetWidth() + curC].InitNode(curR, curC, -1,               -1, 0, GetHeuristicCalc(), GetHeuristicWeight(), r, c);
        //this starting node is definitely going on the OpenList
        astar->nodeDataArray[curR * g_terrain.GetWidth() + curC].listFlag = OnOpen;
        //put the starting node on the OpenList
        astar->OpenList.push_front(astar->nodeDataArray[curR * g_terrain.GetWidth() + curC]);
    }

    //While (Open List is not empty)
    while (astar->OpenList.size() > 0)
    {
        //Pop cheapest node off Open List (parent node)
        std::list<Node>::iterator it = astar->FindCheapestNodeOnOpenList();

        //If node is the Goal Node, then path found (RETURN “found”)
        if (it->row == r && it->col == c)
        {
            DrawGridColors();   //debug draw path

                //put final node on "closed list"
            astar->nodeDataArray[it->row * g_terrain.GetWidth() + it->col].listFlag =                       OnClosed;

            //create waypoint list
            CreateWaypoints(astar->nodeDataArray[it->row * g_terrain.GetWidth() + it->col]);

            //rubberbanding smoothing
            if (m_rubberband)
                RubberbandTest();

            //catmull-rom smoothing
            if (m_smooth)
                ApplyCatmullRom();

            return true;
        }

        //For (all neighboring child nodes)
        for (int pos = 0; pos < 8; ++pos)
        {
            unsigned int neighborRow;
            unsigned int neighborCol;
            float g;
            //skip out of bounds, walls, check corners, and get neightbor coords, and get g
            if (!ValidLocation(pos, it->row, it->col, neighborRow, neighborCol, g))
                continue;
            //skip parent
            if (neighborRow == it->parentRow && neighborCol == it->parentCol)
                continue;

            //Compute its cost, f(x) = g(x) + h(x)
            Node node(neighborRow, neighborCol, it->row, it->col, it->cost + g,                         GetHeuristicCalc(), GetHeuristicWeight(), r, c);
            //creating a new node calculates the cost in the total member

            //If child node isn’t on Open or Closed list, put it on Open List.
            if (astar->nodeDataArray[neighborRow * g_terrain.GetWidth() +                           neighborCol].listFlag == OnNone)
            {
                //update the node data and put on open list
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() + neighborCol].cost                     = node.cost;
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() + neighborCol].total                    = node.total;
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() +                               neighborCol].parentRow = node.parentRow;
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() +                               neighborCol].parentCol = node.parentCol;
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() +                               neighborCol].listFlag = OnOpen;
                astar->OpenList.push_back(astar->nodeDataArray[neighborRow *                                g_terrain.GetWidth() + neighborCol]);
            }

            //If neighbor node is on Open or Closed List, AND this new one is cheaper,
                //(the if check above guarantees that it is on one of the lists, so now we              //just check for being cheaper)
                //(on open AND cheaper) OR (on closed AND cheaper)
            else if ( astar->nodeDataArray[neighborRow * g_terrain.GetWidth() +                         neighborCol].listFlag != OnNone && node.total <
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() +                           neighborCol].total )
            {
                //"remove from closed list" is just changing the listFlag, done when updating               //the nodeDataArray for this node in the next lines
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() + neighborCol].cost =                   node.cost;
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() + neighborCol].total                    = node.total;
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() +                               neighborCol].parentRow = node.parentRow;
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() +                               neighborCol].parentCol = node.parentCol;
                astar->nodeDataArray[neighborRow * g_terrain.GetWidth() +                               neighborCol].listFlag = OnOpen;
                astar->OpenList.push_back(astar->nodeDataArray[neighborRow *                                g_terrain.GetWidth() + neighborCol]);
            }
        }

        //Place parent node on the Closed List (we’re done with it)
        astar->nodeDataArray[it->row * g_terrain.GetWidth() + it->col].listFlag = OnClosed;
        astar->OpenList.erase(it);  //cheapest node on open list was "popped", so remove it

        //If taken too much time this frame (or in single step mode), abort search for now and          //resume next frame (RETURN “working”)
        if (!m_singleStep)
        {
            DrawGridColors();  //debug draw this frame
            return false;
        }
    }

    //Open List empty, thus no path possible (RETURN “fail”)
    return false;
}