public bool Walk(ref int x, ref int y, bool recalculate_when_needed)
{
if (path.Count == 0)
{
return(false);
}
PathFindingDirection d = path[path.Count - 1];
path.RemoveAt(path.Count - 1);
int newx = ox + dirx[(int)d];
int newy = oy + diry[(int)d];
/* check if the path is still valid */
if (!level.IsWalkable(newx, newy))
{
if (!recalculate_when_needed)
{
return(false); /* don't walk */
}
/* calculate a new path */
if (!Compute(ox, oy, dx, dy))
{
return(false); /* cannot find a new path */
}
return(Walk(ref x, ref y, true)); /* walk along the new path */
}
x = newx;
y = newy;
ox = newx;
oy = newy;
return(true);
}
public bool Compute(int ox, int oy, int dx, int dy)
{
this.ox = ox;
this.oy = oy;
this.dx = dx;
this.dy = dy;
path.Clear();
heap.Clear();
if (ox == dx && oy == dy)
{
return(true); /* trivial case */
}
/* check that origin and destination are inside the map */
if (!((uint)ox < (uint)w && (uint)oy < (uint)h))
{
return(false);
}
if (!((uint)dx < (uint)w && (uint)dy < (uint)h))
{
return(false);
}
Array.Clear(grid, 0, w * h);
for (int i = 0; i < w * h; i++)
{
prev[i] = PathFindingDirection.NONE;
}
heur[ox + oy * w] = 1.0f;
TCOD_path_push_cell(ox, oy); /* put the origin cell as a bootstrap */
/* fill the djikstra grid until we reach dx,dy */
TCOD_path_set_cells();
if (grid[dx + dy * w] == 0)
{
return(false); /* no path found */
}
/* there is a path. retrieve it */
do
{
/* walk from destination to origin, using the 'prev' array */
PathFindingDirection step = prev[dx + dy * w];
path.Add(step);
dx -= dirx[(int)step];
dy -= diry[(int)step];
} while (dx != ox || dy != oy);
return(true);
}
public void GetPathElement(int index, out int x, out int y)
{
int pos;
x = ox;
y = oy;
pos = path.Count - 1;
do
{
Contract.Assert(index >= -1);
Contract.Assert(pos >= 0);
PathFindingDirection step = path[pos];
x += dirx[(int)step];
y += diry[(int)step];
pos--;
index--;
} while (index >= 0);
}
public void Reverse()
{
int tmp, i;
tmp = ox;
ox = dx;
dx = tmp;
tmp = oy;
oy = dy;
dy = tmp;
for (i = 0; i < path.Count; i++)
{
PathFindingDirection d = path[i];
d = invdir[(int)d];
path[i] = d;
}
}