// Try to flood fill the map. Each seperate contigious spot gets a different scratch number.
protected int FloodFillWithContigiousNumbers(Map map)
{
ResetScratch(map);
byte currentScratchNumber = 1;
// First we walk the entire map, flood filling each
for (int i = 0; i < map.Width; ++i)
{
for (int j = 0; j < map.Height; ++j)
{
if (map.GetTerrainAt(i, j) == TerrainType.Floor && map.GetScratchAt(i, j) == 0)
{
FloodFill(map, i, j, currentScratchNumber);
currentScratchNumber++;
}
}
}
// If we didn't scratch any tiles, the map must be all walls, bail
if (currentScratchNumber == 1)
throw new MapGenerationFailureException("FillAllSmallerUnconnectedRooms came to a level with all walls?");
return currentScratchNumber;
}
// Make sure map has one connected area
protected bool CheckConnectivity(Map map)
{
const int CheckConnectivityScratchValue = 42;
// Find a clear point
Point clearPoint = GetFirstClearPoint(map);
// Flood fill all connected tiles
FloodFill(map, clearPoint.X, clearPoint.Y, CheckConnectivityScratchValue);
// See if any floor tiles don't have our scratch, if so they are not connected
for (int i = 0; i < map.Width; ++i)
{
for (int j = 0; j < map.Height; ++j)
{
if (map.GetTerrainAt(i, j) == TerrainType.Floor && map.GetScratchAt(i, j) != CheckConnectivityScratchValue)
return false;
}
}
return true;
}
protected void FillAllSmallerUnconnectedRooms(Map map)
{
int currentScratchNumber = FloodFillWithContigiousNumbers(map);
// Walk each tile, and count up the different groups.
int[] numberOfTilesWithThatScratch = new int[currentScratchNumber];
numberOfTilesWithThatScratch.Initialize();
for (int i = 0; i < map.Width; ++i)
{
for (int j = 0; j < map.Height; ++j)
{
if (map.GetTerrainAt(i, j) == TerrainType.Floor)
numberOfTilesWithThatScratch[map.GetScratchAt(i, j)]++;
}
}
if (numberOfTilesWithThatScratch[0] != 0)
throw new MapGenerationFailureException("Some valid tiles didn't get a scratch during FillAllSmallerRooms.");
// Find the largest collection
int biggestNumber = 1;
for (int i = 2; i < currentScratchNumber; ++i)
{
if (numberOfTilesWithThatScratch[i] > numberOfTilesWithThatScratch[biggestNumber])
biggestNumber = i;
}
// Now walk level, and turn every floor tile without that scratch into a wall
for (int i = 0; i < map.Width; ++i)
{
for (int j = 0; j < map.Height; ++j)
{
if (map.GetTerrainAt(i, j) == TerrainType.Floor && map.GetScratchAt(i, j) != biggestNumber)
map.SetTerrainAt(i, j, TerrainType.Wall);
// And reset the scratch while we're here
map.SetScratchAt(i, j, 0);
}
}
if (!CheckConnectivity(map))
throw new MapGenerationFailureException("FillAllSmallerUnconnectedRooms produced a non-connected map.");
}
protected void FloodFill(Map map, int x, int y, byte scratchValue)
{
if (!map.IsPointOnMap(x, y))
return;
if (map.GetTerrainAt(x, y) == TerrainType.Floor && map.GetScratchAt(x, y) == 0)
{
map.SetScratchAt(x, y, scratchValue);
FloodFill(map, x + 1, y, scratchValue);
FloodFill(map, x - 1, y, scratchValue);
FloodFill(map, x, y + 1, scratchValue);
FloodFill(map, x, y - 1, scratchValue);
}
}
