/// <summary>
/// Computes Worley/Voroni noise for the given seed.
/// </summary>
/// <param name="distFunc">
/// The function to get the distance between two positions.
/// </param>
/// <param name="distsToValue">
/// Takes in the closest and second-closest distances and outputs a noise value from them.
/// </param>
/// <example>
/// //A standard effect is straight-line distance and using the closest distance value.
/// float noiseVal = WorleyNoise(seed, Vector2.Distance, (f1, f2) => f1);
/// //Another nice effect is distance squared and using the average of both distance values.
/// float noiseVal2 = WorleyNoise(seed,
/// (v1, v2) => (v1 - v2).sqrMagnitude,
/// (f1, f2) => (f1 + f2) * 0.5f);
/// </example>
public static float WorleyNoise(Vector2 seed, Func <Vector2, Vector2, float> distFunc,
Func <float, float, float> distsToValue)
{
//Get the min corner of each of the 9 grid cells near the seed value.
Vector2 posCenter = new Vector2(Mathf.Floor(seed.x), Mathf.Floor(seed.y)),
posMinCorner = posCenter - Vector2.one,
posMaxCorner = posCenter + Vector2.one,
pos4 = new Vector2(posCenter.x, posMinCorner.y),
pos5 = new Vector2(posMaxCorner.x, posMinCorner.y),
pos6 = new Vector2(posMinCorner.x, posCenter.y),
pos7 = new Vector2(posMaxCorner.x, posCenter.y),
pos8 = new Vector2(posMinCorner.x, posMaxCorner.y),
pos9 = new Vector2(posCenter.x, posMaxCorner.y);
//Get a random point inside each of these cells
// and get the distance from the seed pos to the two closest points.
float min1 = float.PositiveInfinity,
min2 = float.PositiveInfinity;
Utils.GetWorleyMins(ref min1, ref min2, distFunc(Utils.GetWorleyPos(posCenter) + posCenter, seed));
Utils.GetWorleyMins(ref min1, ref min2, distFunc(Utils.GetWorleyPos(posMinCorner) + posMinCorner, seed));
Utils.GetWorleyMins(ref min1, ref min2, distFunc(Utils.GetWorleyPos(posMaxCorner) + posMaxCorner, seed));
Utils.GetWorleyMins(ref min1, ref min2, distFunc(Utils.GetWorleyPos(pos4) + pos4, seed));
Utils.GetWorleyMins(ref min1, ref min2, distFunc(Utils.GetWorleyPos(pos5) + pos5, seed));
Utils.GetWorleyMins(ref min1, ref min2, distFunc(Utils.GetWorleyPos(pos6) + pos6, seed));
Utils.GetWorleyMins(ref min1, ref min2, distFunc(Utils.GetWorleyPos(pos7) + pos7, seed));
Utils.GetWorleyMins(ref min1, ref min2, distFunc(Utils.GetWorleyPos(pos8) + pos8, seed));
Utils.GetWorleyMins(ref min1, ref min2, distFunc(Utils.GetWorleyPos(pos9) + pos9, seed));
//Filter these distance values into some noise value.
return(distsToValue(min1, min2));
}
/// <summary>
/// Computes Worley/Voroni noise for the given seed.
/// </summary>
/// <param name="distsToValue">
/// Takes in the closest and second-closest distances and outputs a noise value from them.
/// </param>
public static float WorleyNoise(float seed, Func <float, float, float> distsToValue)
{
//Get the min corner of each of the 9 grid cells near the seed value.
float posMid = Mathf.Floor(seed),
posLess = posMid - 1.0f,
posMore = posMid + 1.0f;
//Get a random point inside each of these cells
// and get the distance from the seed pos to the two closest points.
float min1 = float.PositiveInfinity,
min2 = float.PositiveInfinity;
Utils.GetWorleyMins(ref min1, ref min2, Mathf.Abs(seed - (posMid + WhiteNoise(posMid))));
Utils.GetWorleyMins(ref min1, ref min2, Mathf.Abs(seed - (posLess + WhiteNoise(posLess))));
Utils.GetWorleyMins(ref min1, ref min2, Mathf.Abs(seed - (posMore + WhiteNoise(posMore))));
//Filter these distance values into some noise value.
return(distsToValue(min1, min2));
}
/// <summary>
/// Returns a pseudo-random value from 0 to 1 using the given seed.
/// </summary>
public static float WhiteNoise(Vector2 seed)
{
return(new PRNG(Utils.GetHashCode(seed)).NextFloat());
}
