public static void ge_p3_tobytes(byte[] s, int offset, ref GroupElementP3 h)
{
FieldElement recip;
FieldElement x;
FieldElement y;
FieldOperations.fe_invert(out recip, ref h.Z);
FieldOperations.fe_mul(out x, ref h.X, ref recip);
FieldOperations.fe_mul(out y, ref h.Y, ref recip);
FieldOperations.fe_tobytes(s, offset, ref y);
s[offset + 31] ^= (byte)(FieldOperations.fe_isnegative(ref x) << 7);
}
public static void scalarmult(
byte[] q, int qoffset,
byte[] n, int noffset,
byte[] p, int poffset)
{
FieldElement p0;
FieldElement q0;
FieldOperations.fe_frombytes2(out p0, p, poffset);
scalarmult(out q0, n, noffset, ref p0);
FieldOperations.fe_tobytes(q, qoffset, ref q0);
}