/**
* Monotone Chain algorithm. See
* http://en.wikibooks.org/wiki/Algorithm_Implementation/Geometry/Convex_hull/Monotone_chain
*/
static xyYPoint[] findConvexHull(xyYPoint[] points)
{
int n = points.Length, k = 0;
xyYPoint[] tmpHull = new xyYPoint[2 * n];
Array.Sort(points, new xyYPointComparer());
// Build lower hull
for (int i = 0; i < n; i++)
{
while (k >= 2 && cross(tmpHull[k - 2], tmpHull[k - 1], points[i]) <= 0)
{
k--;
}
tmpHull[k++] = points[i];
}
// Build upper hull
for (int i = n - 2, t = k + 1; i >= 0; i--)
{
while (k >= t && cross(tmpHull[k - 2], tmpHull[k - 1], points[i]) <= 0)
{
k--;
}
tmpHull[k++] = points[i];
}
tmpHull [k - 1].x = -1000.0; // remove repetition
return(tmpHull);
}
/**
* Computes the 'sharkin' points.
*/
static void computeSharkfin(IList <double> mfX, IList <double> mfY, IList <double> mfZ, ref xyYPoint[] Sharkfin, ref xyYPoint[] SortedSharkfin)
{
var n = mfX.Count;
Sharkfin = new xyYPoint[n];
for (int i = 0; i < n; i++)
{
var XYZ = mfX [i] + mfY [i] + mfZ [i];
if (Math.Abs(XYZ) < double.Epsilon)
{
Sharkfin [i] = new xyYPoint {
x = 0.0, y = 0.0
};
}
else
{
Sharkfin [i] = new xyYPoint {
x = mfX [i] / XYZ, y = mfY [i] / XYZ
};
}
}
// Used to speedup the convex hull algorithm
SortedSharkfin = (xyYPoint[])Sharkfin.Clone();
Array.Sort(SortedSharkfin, new xyYPointComparer());
}
/**
* <inheritdoc />
*/
public override bool IsInsideColorSpace(bool highPrecision = false)
{
// Fast checks
if (y > 1.0 - x || y < (x - 0.25) * 0.5 || y < 0.4 - x * 4 || y >= 0.85)
{
return(false);
}
xyYPoint[] points;
if (highPrecision)
{
points = new xyYPoint[SortedSharkfin1Nm.Length + 1];
Array.Copy(SortedSharkfin1Nm, 0, points, 0, SortedSharkfin1Nm.Length);
points [SortedSharkfin1Nm.Length] = new xyYPoint {
x = x, y = y
};
}
else
{
points = new xyYPoint[SortedSharkfin5Nm.Length + 1];
Array.Copy(SortedSharkfin5Nm, 0, points, 0, SortedSharkfin5Nm.Length);
points [SortedSharkfin5Nm.Length] = new xyYPoint {
x = x, y = y
};
}
xyYPoint[] convexHull = findConvexHull(points);
for (int i = 0; i < convexHull.Length; i++)
{
if (convexHull [i].x == x && convexHull [i].y == y)
{
return(false);
}
}
return(true);
}
/**
* Used inside findConvexHull method.
*/
static double cross(xyYPoint O, xyYPoint A, xyYPoint B)
{
return (A.x - O.x) * (B.y - O.y) - (A.y - O.y) * (B.x - O.x);
}
/**
* Monotone Chain algorithm. See
* http://en.wikibooks.org/wiki/Algorithm_Implementation/Geometry/Convex_hull/Monotone_chain
*/
static xyYPoint[] findConvexHull(xyYPoint[] points)
{
int n = points.Length, k = 0;
xyYPoint[] tmpHull = new xyYPoint[2 * n];
Array.Sort (points, new xyYPointComparer ());
// Build lower hull
for (int i = 0; i < n; i++) {
while (k >= 2 && cross(tmpHull[k - 2], tmpHull[k - 1], points[i]) <= 0)
k--;
tmpHull[k++] = points[i];
}
// Build upper hull
for (int i = n - 2, t = k + 1; i >= 0; i--) {
while (k >= t && cross(tmpHull[k - 2], tmpHull[k - 1], points[i]) <= 0)
k--;
tmpHull[k++] = points[i];
}
tmpHull [k - 1].x = -1000.0; // remove repetition
return tmpHull;
}
/**
* <inheritdoc />
*/
public override bool IsInsideColorSpace(bool highPrecision = false)
{
// Fast checks
if (y > 1.0 - x || y < (x - 0.25) * 0.5 || y < 0.4 - x * 4 || y >= 0.85)
return false;
xyYPoint[] points;
if (highPrecision) {
points = new xyYPoint[SortedSharkfin1Nm.Length + 1];
Array.Copy (SortedSharkfin1Nm, 0, points, 0, SortedSharkfin1Nm.Length);
points [SortedSharkfin1Nm.Length] = new xyYPoint{ x = x, y = y };
} else {
points = new xyYPoint[SortedSharkfin5Nm.Length + 1];
Array.Copy (SortedSharkfin5Nm, 0, points, 0, SortedSharkfin5Nm.Length);
points [SortedSharkfin5Nm.Length] = new xyYPoint{ x = x, y = y };
}
xyYPoint[] convexHull = findConvexHull (points);
for (int i = 0; i < convexHull.Length; i++) {
if (convexHull [i].x == x && convexHull [i].y == y)
return false;
}
return true;
}
/**
* Computes the 'sharkin' points.
*/
static void computeSharkfin(IList<double> mfX, IList<double> mfY, IList<double> mfZ, ref xyYPoint[] Sharkfin, ref xyYPoint[] SortedSharkfin)
{
var n = mfX.Count;
Sharkfin = new xyYPoint[n];
for (int i = 0; i < n; i++) {
var XYZ = mfX [i] + mfY [i] + mfZ [i];
if (Math.Abs (XYZ) < double.Epsilon) {
Sharkfin [i] = new xyYPoint { x = 0.0, y = 0.0 };
} else {
Sharkfin [i] = new xyYPoint { x = mfX [i] / XYZ, y = mfY [i] / XYZ };
}
}
// Used to speedup the convex hull algorithm
SortedSharkfin = (xyYPoint[])Sharkfin.Clone();
Array.Sort (SortedSharkfin, new xyYPointComparer());
}
/**
* Used inside findConvexHull method.
*/
static double cross(xyYPoint O, xyYPoint A, xyYPoint B)
{
return((A.x - O.x) * (B.y - O.y) - (A.y - O.y) * (B.x - O.x));
}
