public static HashSet <Point> ComputeFOVFor(Rules rules, Actor actor, WorldTime time, Weather weather)
{
Location fromLocation = actor.Location;
HashSet <Point> visibleSet = new HashSet <Point>();
Point from = fromLocation.Position;
Map map = fromLocation.Map;
int maxRange = rules.ActorFOV(actor, time, weather);
//////////////////////////////////////////////
// Brute force ray-casting with wall fix pass
//////////////////////////////////////////////
int xmin = from.X - maxRange;
int xmax = from.X + maxRange;
int ymin = from.Y - maxRange;
int ymax = from.Y + maxRange;
map.TrimToBounds(ref xmin, ref ymin);
map.TrimToBounds(ref xmax, ref ymax);
Point to = new Point();
List <Point> wallsToFix = new List <Point>();
// 1st pass : trace line and remember walls that are not visible for 2nd pass.
for (int x = xmin; x <= xmax; x++)
{
to.X = x;
for (int y = ymin; y <= ymax; y++)
{
to.Y = y;
// Distance check.
if (rules.LOSDistance(from, to) > maxRange)
{
continue;
}
// If we already know tile is visible, pass.
if (visibleSet.Contains(to))
{
continue;
}
// Trace line.
if (!FOVSub(fromLocation, to, maxRange, ref visibleSet))
{
// if its a wall (in FoV terms), remember.
bool isFovWall = false;
Tile tile = map.GetTileAt(x, y);
MapObject mapObj = map.GetMapObjectAt(x, y);
if (!tile.Model.IsTransparent && !tile.Model.IsWalkable)
{
isFovWall = true;
}
else if (mapObj != null)
{
isFovWall = true;
}
if (isFovWall)
{
wallsToFix.Add(to);
}
// next.
continue;
}
// Visible.
visibleSet.Add(to);
}
}
// 2nd pass : wall fix.
List <Point> fixedWalls = new List <Point>(wallsToFix.Count);
foreach (Point wallP in wallsToFix)
{
int count = 0;
foreach (Direction d in Direction.COMPASS)
{
Point next = wallP + d;
if (visibleSet.Contains(next))
{
Tile tile = map.GetTileAt(next.X, next.Y);
if (tile.Model.IsTransparent && tile.Model.IsWalkable)
{
++count;
}
}
}
if (count >= 3)
{
fixedWalls.Add(wallP);
}
}
foreach (Point fixedWall in fixedWalls)
{
visibleSet.Add(fixedWall);
}
return(visibleSet);
}
