private void WriteVarlenFBPair(float a, float b)
{
int a1616 = (int)(a * 65536);
int b1616 = (int)(b * 65536);
int nbits = Math.Max(RequiredBits(a1616), RequiredBits(b1616));
this.WriteUBits((uint)nbits, 5);
this.WriteSBits(a1616, nbits);
this.WriteSBits(b1616, nbits);
}