// ----------------------------------------------------------------------------------
// Actual A* algorithm: return number of steps in the creation of the path or -1 ----
// ----------------------------------------------------------------------------------
int j1PathFinding::CreatePath(const iPoint& origin, const iPoint& destination)
{
int ret = 0;
// TODO 1: if origin or destination are not walkable, return -1
if (IsWalkable(origin) == true && IsWalkable(destination) == true)
{
// TODO 2: Create three lists: open, close
// Add the origin tile to open
// Iterate while we have tile in the open list
PathList open;
PathList closed;
PathNode origin_tile;
origin_tile.pos = origin;
open.list.add(origin_tile);
while (open.Find(origin) != NULL)
{
// TODO 3: Move the lowest score cell from open list to the closed list
p2List_item<PathNode>* open_lowestScore = open.GetNodeLowestScore();
closed.list.add(open_lowestScore->data);
open.list.del(open_lowestScore);
// TODO 4: If we just added the destination, we are done!
// Backtrack to create the final path
// Use the Pathnode::parent and Flip() the path when you are finish
if (open.Find(destination) != NULL)
{
}
// TODO 5: Fill a list of all adjancent nodes
// TODO 6: Iterate adjancent nodes:
// ignore nodes in the closed list
// If it is NOT found, calculate its F and add it to the open list
// If it is already in the open list, check if it is a better path (compare G)
// If it is a better path, Update the parent
}
}
else
ret = -1;
return ret;
}
// ----------------------------------------------------------------------------------
// Actual A* algorithm: return number of steps in the creation of the path or -1 ----
// ----------------------------------------------------------------------------------
int j1PathFinding::CreatePath(const iPoint& origin, const iPoint& destination)
{
// TODO 1: if origin or destination are not walkable, return -1
last_path.Clear();
if (IsWalkable(origin) && IsWalkable(destination))
{
uint num = 0;
PathList open;
PathList closed;
PathList adjacents;
PathNode source;
p2List_item<PathNode>* closest;
p2List_item<PathNode>* operations;
bool isfinish = false;
source.pos.x = origin.x;
source.pos.y = origin.y;
source.h = (abs(origin.x - destination.x) + abs(origin.y - destination.y));
source.g = 0;
source.parent = NULL;
open.list.add(source);
num = open.Find(source.pos)->data.FindWalkableAdjacents(adjacents);
closed.list.add(open.Find(source.pos)->data);
open.list.del(open.Find(source.pos));
while (isfinish == NULL)
{
for (int i = 0; i < num; i++)
{
adjacents.list.At(i)->data.parent = &source;
adjacents.list.At(i)->data.CalculateF(destination);
adjacents.list.At(i)->data.h = adjacents.list.At(i)->data.pos.DistanceTo(destination);
if (adjacents.list.At(i)->data.pos.DistanceManhattan(destination) == 0)
{
closed.list.add(adjacents.list.At(i)->data);
isfinish = true;
break;
}
if (closed.Find(adjacents.list.At(i)->data.pos)) { // if this adjacent square is already in the closed list ignore it
continue; // Go to the next adjacent square
}
if (open.Find(adjacents.list.At(i)->data.pos) == NULL)
{
open.list.add(adjacents.list.At(i)->data);
}
else { // if its already in the open list
}
}
adjacents.list.clear();
closest = open.GetNodeLowestScore();
num = open.Find(closest->data.pos)->data.FindWalkableAdjacents(adjacents);
closed.list.add(closest->data);
source = closest->data;
}
for (int i = 0; i < closed.list.count(); i++)
{
last_path.PushBack(closed.list.At(i)->data.pos);
LOG("Point: %d, %d", last_path.At(i)->x, last_path.At(i)->y);
}
last_path.Flip();
}
// TODO 2: Create three lists: open, close
// Add the origin tile to open
// Iterate while we have tile in the open list
// TODO 3: Move the lowest score cell from open list to the closed list
// TODO 4: If we just added the destination, we are done!
// Backtrack to create the final path
// Use the Pathnode::parent and Flip() the path when you are finish
// TODO 5: Fill a list of all adjancent nodes
// TODO 6: Iterate adjancent nodes:
// ignore nodes in the closed list
// If it is NOT found, calculate its F and add it to the open list
// If it is already in the open list, check if it is a better path (compare G)
// If it is a better path, Update the parent
return -1;
}
// ----------------------------------------------------------------------------------
// Actual A* algorithm: return number of steps in the creation of the path or -1 ----
// ----------------------------------------------------------------------------------
int j1PathFinding::CreatePath(const iPoint& origin, const iPoint& destination)
{
// TODO 1: if origin or destination are not walkable, return -1
if (!IsWalkable(origin) || !IsWalkable(destination))
return -1;
// TODO 2: Create two lists: open, close
// Add the origin tile to open
// Iterate while we have tile in the open list
PathList open;
PathList close;
PathNode Origin;
PathNode Destination;
p2List_item<PathNode>* current_node;
current_node = open.list.start;
Origin.pos = origin;
Destination.pos = destination;
if (open.Find(origin) == nullptr)
open.list.add(Origin);
p2List_item<PathNode>* lowest = nullptr;
// lowest = open.list.start;
while (open.list.count() > 0 && current_node) {
open.list.add(current_node->data);
lowest = open.GetNodeLowestScore();
open.list.del(open.GetNodeLowestScore());
close.list.add(open.GetNodeLowestScore()->data);
if (destination == lowest->data.pos) {
last_path.PushBack(lowest->data.pos);
last_path.Flip();
}
current_node = current_node->next;
}
// TODO 3: Move the lowest score cell from open list to the closed list
// TODO 4: If we just added the destination, we are done!
// Backtrack to create the final path
// Use the Pathnode::parent and Flip() the path when you are finish
// TODO 5: Fill a list of all adjancent nodes
// TODO 6: Iterate adjancent nodes:
// ignore nodes in the closed list
// If it is NOT found, calculate its F and add it to the open list
// If it is already in the open list, check if it is a better path (compare G)
// If it is a better path, Update the parent
return -1;
}
// ----------------------------------------------------------------------------------
// Actual A* algorithm: return number of steps in the creation of the path or -1 ----
// ----------------------------------------------------------------------------------
int j1PathFinding::CreatePath(const iPoint& origin, const iPoint& destination)
{
if (IsWalkable(origin) && IsWalkable(destination))
{
// TODO 2: Create three lists: open, close ,adjacent
PathList open;
PathList closed;
PathList adjacent;
// Add the origin tile to open
open.list.add(PathNode(0, 0, origin, NULL));
// Iterate while we have tile in the open list
do
{
// TODO 3: Move the lowest score cell from open list to the closed list
p2List_item<PathNode>* lowest_score = open.GetNodeLowestScore();
p2List_item<PathNode>* node = closed.list.add(lowest_score->data);
// delete de lowest score from the open list
open.list.del(lowest_score);
// TODO 4: If we just added the destination, we are done!
if (node->data.pos == destination)
{
//clean the path we used before
last_path.Clear();
// Backtrack to create the final path
const PathNode* path_node = &node->data;
while (path_node)
{
// Use the Pathnode::parent and Flip() the path when you are finish
last_path.PushBack(path_node->pos);
path_node = path_node->parent;
}
last_path.Flip();
return last_path.Count();
}
// TODO 5: Fill a list of all adjancent nodes
node->data.FindWalkableAdjacents(adjacent);
p2List_item<PathNode>* adjacent_items = adjacent.list.start;
// TODO 6: Iterate adjancent nodes:
for (; adjacent_items; adjacent_items = adjacent_items->next)
{
// ignore nodes in the closed list
if (closed.Find(adjacent_items->data.pos) != NULL)
{
continue;
}
p2List_item<PathNode>* adjacent_open = open.Find(adjacent_items->data.pos);
// If it is NOT found, calculate its F and add it to the open list
if (adjacent_open == NULL)
{
adjacent_items->data.CalculateF(destination);
open.list.add(adjacent_items->data);
}
else
// If it is already in the open list, check if it is a better path (compare G)
{
if (adjacent_open->data.g > adjacent_items->data.g)
{
// If it is a better path, Update the parent
adjacent_open->data.parent = adjacent_items->data.parent;
adjacent_open->data.CalculateF(destination);
}
}
}
} while (open.list.count()>0);
}
return -1;
}
// ----------------------------------------------------------------------------------
// Actual A* algorithm: return number of steps in the creation of the path or -1 ----
// ----------------------------------------------------------------------------------
int j1PathFinding::CreatePath(const iPoint& origin, const iPoint& destination)
{
int ret = -1;
int iterations = 0;
if(IsWalkable(origin) && IsWalkable(destination))
{
PathList open;
PathList closed;
PathList adjacent;
// Start pushing the origin in the open list
open.list.add(PathNode(0, 0, origin, NULL));
// Iterate while we have open destinations to visit
do
{
// Move the lowest score cell from open list to the closed list
p2List_item<PathNode>* lowest = open.GetNodeLowestScore();
p2List_item<PathNode>* node = closed.list.add(lowest->data);
open.list.del(lowest);
// If destination was added, we are done!
if(node->data.pos == destination)
{
last_path.Clear();
// Backtrack to create the final path
const PathNode* path_node = &node->data;
while(path_node)
{
last_path.PushBack(path_node->pos);
path_node = path_node->parent;
}
last_path.Flip();
ret = last_path.Count();
LOG("Created path of %d steps in %d iterations", ret, iterations);
break;
}
// Fill a list with all adjacent nodes
adjacent.list.clear();
node->data.FindWalkableAdjacents(adjacent);
p2List_item<PathNode>* item = adjacent.list.start;
for(; item; item = item->next)
{
if(closed.Find(item->data.pos) != NULL)
continue;
p2List_item<PathNode>* adjacent_in_open = open.Find(item->data.pos);
if(adjacent_in_open == NULL)
{
item->data.CalculateF(destination);
open.list.add(item->data);
}
else
{
if(adjacent_in_open->data.g > item->data.g + 1)
{
adjacent_in_open->data.parent = item->data.parent;
adjacent_in_open->data.CalculateF(destination);
}
}
}
++iterations;
} while(open.list.count() > 0);
}
return ret;
}
