/// <summary>
/// Calculate the the hash-code for a horizontal line
/// </summary>
/// <param name="y">int with y coordinate</param>
/// <param name="right">optional x starting coordinate of the hash calculation</param>
/// <param name="left">optional x ending coordinate of the hash calculation</param>
/// <returns>uint with the hash</returns>
public uint HorizontalHash(int y, int?right = null, int?left = null)
{
var offset = (left ?? Left) * BytesPerPixel + y * Stride;
var length = (right ?? Right) - (left ?? Left) * BytesPerPixel;
var hash = new Murmur3(Seed, (uint)length);
while (length >= 4)
{
hash.AddBytes(Pointer[offset++], Pointer[offset++], Pointer[offset++], Pointer[offset++]);
length -= 4;
}
switch (length)
{
case 3:
hash.AddTrailingBytes(Pointer[offset++], Pointer[offset++], Pointer[offset]);
break;
case 2:
hash.AddTrailingBytes(Pointer[offset++], Pointer[offset]);
break;
case 1:
hash.AddTrailingBytes(Pointer[offset]);
break;
}
return(hash.CalculatedHash);
}
