public double Get(double x, double y)
{
if (Mode == VoronoiMode.FrontierDetection)
{
var result = GetCells(x, y, 2);
//Return the distance between the two nearest points
return(result[1].DistanceSquared - result[0].DistanceSquared);
}
else
{
x *= Frequency;
y *= Frequency;
if (NoiseBorder != null)
{
x += NoiseBorder.Get(x, 0);
y += NoiseBorder.Get(0, y);
}
int xInt = (x > 0.0 ? (int)x : (int)x - 1);
int yInt = (y > 0.0 ? (int)y : (int)y - 1);
double minDist = double.MaxValue;
int xCell = 0;
int yCell = 0;
// Inside each unit cube, there is a seed point at a random position. Go
// through each of the nearby cubes until we find a cube with a seed point
// that is closest to the specified position.
for (int yCur = yInt - 2; yCur <= yInt + 2; yCur++)
{
for (int xCur = xInt - 2; xCur <= xInt + 2; xCur++)
{
// Calculate the position and distance to the seed point inside of
// this unit cube.
double xPos = xCur + (ValueNoise(xCur, yCur, Seed + 1) * Noisiness);
double yPos = yCur + (ValueNoise(xCur, yCur, Seed + 2) * Noisiness);
double xDist = xPos - x;
double yDist = yPos - y;
double dist = xDist * xDist + yDist * yDist;
if (dist < minDist)
{
// This seed point is closer to any others found so far, so record
minDist = dist;
xCell = xCur;
yCell = yCur;
}
}
}
// Return the calculated distance with the displacement value applied.
return(ValueNoise(xCell, yCell, Seed));
}
}
public VoronoiCell[] GetCells(double x, double y, int nbrCells = 4)
{
VoronoiCell[] cells = new VoronoiCell[nbrCells];
//Init result
for (int i = 0; i < nbrCells; i++)
{
cells[i] = new VoronoiCell()
{
DistanceSquared = double.MaxValue
};
}
x *= Frequency;
y *= Frequency;
if (NoiseBorder != null)
{
x += NoiseBorder.Get(x, 0);
y += NoiseBorder.Get(0, y);
}
int xInt = (x > 0.0 ? (int)x : (int)x - 1);
int yInt = (y > 0.0 ? (int)y : (int)y - 1);
// Inside each unit cube, there is a seed point at a random position. Go
// through each of the nearby cubes until we find a cube with a seed point
// that is closest to the specified position.
int highestFreeCellsIndex = 0;
for (int yCur = yInt - 2; yCur <= yInt + 2; yCur++)
{
for (int xCur = xInt - 2; xCur <= xInt + 2; xCur++)
{
// Calculate the position and distance to the seed point inside of
// this unit cube.
double xPos = xCur + (ValueNoise(xCur, yCur, Seed) * Noisiness);
double yPos = yCur + (ValueNoise(xCur, yCur, Seed + 1) * Noisiness);
double xDist = xPos - x;
double yDist = yPos - y;
double dist = xDist * xDist + yDist * yDist;
for (int c = 0; c < nbrCells; c++)
{
if (dist < cells[c].DistanceSquared)
{
if (c < highestFreeCellsIndex)
{
//Shift array to right if needed
Array.Copy(cells, c, cells, c + 1, cells.Length - c - 1);
}
//Add new item at correct place (keeping the cells ordered in the list)
cells[c].DistanceSquared = dist;
cells[c].CellId = new Vector2I(xCur, yCur);
highestFreeCellsIndex++;
break;
}
}
}
}
// Return the calculated distance with the displacement value applied.
return(cells);
}