void AddNeighbor(Queue <FloodFillPixelInfo> queue, ref FloodFillPixelInfo info, int textureSize, int dx, int dy, float decayMultiplier)
{
FloodFillPixelInfo neighbor = info;
neighbor.currentPixel.x += dx;
neighbor.currentPixel.y += dy;
if (neighbor.currentPixel.x < 0 || neighbor.currentPixel.x >= textureSize ||
neighbor.currentPixel.y < 0 || neighbor.currentPixel.y >= textureSize)
{
// Out of bounds
return;
}
var distance = neighbor.DistanceToSource();
var weight = (neighbor.startValue - distance / textureSize * decayMultiplier);
weight = Mathf.Clamp01(weight);
if (weight <= 0)
{
return;
}
int nx = neighbor.currentPixel.x;
int ny = neighbor.currentPixel.y;
float existingWeight = splatData.Data[nx, ny];
if (weight > existingWeight)
{
splatData.Data[nx, ny] = weight;
queue.Enqueue(neighbor);
}
}
/// <summary>
/// flood fills from every pixel whose value is are greater than 0.
/// This creates a nice blur like effect. Useful for making thick lines from the generated map
/// </summary>
/// <param name="splatData"></param>
/// <param name="decay"></param>
public void DecayFloodFill(float decayMultiplier)
{
var sw = System.Diagnostics.Stopwatch.StartNew();
int textureSize = splatData.Data.GetLength(0);
var queue = new Queue <FloodFillPixelInfo>();
for (int y = 0; y < textureSize; y++)
{
for (int x = 0; x < textureSize; x++)
{
float value = splatData.Data[x, y];
if (value > 0.01f)
{
var info = new FloodFillPixelInfo();
info.currentPixel = new IntVector2(x, y);
info.sourcePixel = new IntVector2(x, y);
info.startValue = value;
queue.Enqueue(info);
}
}
}
while (queue.Count > 0)
{
var front = queue.Dequeue();
AddNeighbor(queue, ref front, textureSize, -1, 0, decayMultiplier);
AddNeighbor(queue, ref front, textureSize, 1, 0, decayMultiplier);
AddNeighbor(queue, ref front, textureSize, 0, 1, decayMultiplier);
AddNeighbor(queue, ref front, textureSize, 0, -1, decayMultiplier);
}
sw.Stop();
Debug.Log("Time elapsed: " + (sw.ElapsedMilliseconds / 1000.0f) + " s");
}
