public override void Apply(TilemapStructure tilemap)
{
_random = new System.Random(tilemap.Grid.Seed);
var rivers = new List <DrunkenRiver>();
var validStartPositions = TilemapHelper.GetTilesByType(tilemap, StartingTileTypes.Select(a => (int)a));
var amountOfRivers = _random.Next(MinRiverQuota, MaxRiverQuota + 1);
for (int i = 0; i < amountOfRivers; i++)
{
// Get valid startPoint with respect to distance between existing rivers
var startPoint = GetValidStartPosition(validStartPositions, rivers);
if (!startPoint.HasValue)
{
break;
}
// Find valid endPos (closest deep water tile to startPos)
var endPos = TilemapHelper.FindClosestTileByType(tilemap, startPoint.Value, (int)GroundTileType.DeepWater);
if (!endPos.HasValue)
{
break;
}
// Build river from start to end position
var river = new DrunkenRiver(_random, RiverDriftChance, startPoint.Value, endPos.Value);
if (river.Build())
{
rivers.Add(river);
}
}
// Set river tiles into tilemap
int riverTileId = (int)GroundTileType.River;
foreach (var riverPosition in rivers.SelectMany(a => a.RiverPositions))
{
tilemap.SetTile(riverPosition.x, riverPosition.y, riverTileId);
}
}