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public static GetWNafPreCompInfo ( ECPoint p ) : |
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| p | ECPoint | |
| return | ||
public static ECPoint MapPointWithPrecomp(ECPoint p, int width, bool includeNegated, ECPointMap pointMap)
{
ECCurve curve = p.Curve;
WNafPreCompInfo wNafPreCompInfo = WNafUtilities.Precompute(p, width, includeNegated);
ECPoint eCPoint = pointMap.Map(p);
WNafPreCompInfo wNafPreCompInfo2 = WNafUtilities.GetWNafPreCompInfo(curve.GetPreCompInfo(eCPoint, WNafUtilities.PRECOMP_NAME));
ECPoint twice = wNafPreCompInfo.Twice;
if (twice != null)
{
ECPoint twice2 = pointMap.Map(twice);
wNafPreCompInfo2.Twice = twice2;
}
ECPoint[] preComp = wNafPreCompInfo.PreComp;
ECPoint[] array = new ECPoint[preComp.Length];
for (int i = 0; i < preComp.Length; i++)
{
array[i] = pointMap.Map(preComp[i]);
}
wNafPreCompInfo2.PreComp = array;
if (includeNegated)
{
ECPoint[] array2 = new ECPoint[array.Length];
for (int j = 0; j < array2.Length; j++)
{
array2[j] = array[j].Negate();
}
wNafPreCompInfo2.PreCompNeg = array2;
}
curve.SetPreCompInfo(eCPoint, WNafUtilities.PRECOMP_NAME, wNafPreCompInfo2);
return(eCPoint);
}
public static WNafPreCompInfo Precompute(ECPoint p, int width, bool includeNegated)
{
ECCurve curve = p.Curve;
WNafPreCompInfo wNafPreCompInfo = WNafUtilities.GetWNafPreCompInfo(curve.GetPreCompInfo(p, WNafUtilities.PRECOMP_NAME));
int num = 0;
int num2 = 1 << Math.Max(0, width - 2);
ECPoint[] array = wNafPreCompInfo.PreComp;
if (array == null)
{
array = WNafUtilities.EMPTY_POINTS;
}
else
{
num = array.Length;
}
if (num < num2)
{
array = WNafUtilities.ResizeTable(array, num2);
if (num2 == 1)
{
array[0] = p.Normalize();
}
else
{
int i = num;
if (i == 0)
{
array[0] = p;
i = 1;
}
ECFieldElement eCFieldElement = null;
if (num2 == 2)
{
array[1] = p.ThreeTimes();
}
else
{
ECPoint eCPoint = wNafPreCompInfo.Twice;
ECPoint eCPoint2 = array[i - 1];
if (eCPoint == null)
{
eCPoint = array[0].Twice();
wNafPreCompInfo.Twice = eCPoint;
if (ECAlgorithms.IsFpCurve(curve) && curve.FieldSize >= 64)
{
switch (curve.CoordinateSystem)
{
case 2:
case 3:
case 4:
{
eCFieldElement = eCPoint.GetZCoord(0);
eCPoint = curve.CreatePoint(eCPoint.XCoord.ToBigInteger(), eCPoint.YCoord.ToBigInteger());
ECFieldElement eCFieldElement2 = eCFieldElement.Square();
ECFieldElement scale = eCFieldElement2.Multiply(eCFieldElement);
eCPoint2 = eCPoint2.ScaleX(eCFieldElement2).ScaleY(scale);
if (num == 0)
{
array[0] = eCPoint2;
}
break;
}
}
}
}
while (i < num2)
{
eCPoint2 = (array[i++] = eCPoint2.Add(eCPoint));
}
}
curve.NormalizeAll(array, num, num2 - num, eCFieldElement);
}
}
wNafPreCompInfo.PreComp = array;
if (includeNegated)
{
ECPoint[] array2 = wNafPreCompInfo.PreCompNeg;
int j;
if (array2 == null)
{
j = 0;
array2 = new ECPoint[num2];
}
else
{
j = array2.Length;
if (j < num2)
{
array2 = WNafUtilities.ResizeTable(array2, num2);
}
}
while (j < num2)
{
array2[j] = array[j].Negate();
j++;
}
wNafPreCompInfo.PreCompNeg = array2;
}
curve.SetPreCompInfo(p, WNafUtilities.PRECOMP_NAME, wNafPreCompInfo);
return(wNafPreCompInfo);
}
public static WNafPreCompInfo GetWNafPreCompInfo(ECPoint p)
{
return(WNafUtilities.GetWNafPreCompInfo(p.Curve.GetPreCompInfo(p, WNafUtilities.PRECOMP_NAME)));
}
