[Mono-list] System.Drawing.Drawing2D

[Lloyd Dupont]

just look at your code:
       public override int GetHashCode()
        {
            // TODO: find a better hash function than det(M)
            return (int)(m[0] * m[3] - m[2] * m[1]);
        }
mhh, a problem is that det(Mat) would be equal to product of eigen
value, and there is specific value for this, for example rotation
matrix would have det = 1.

why not something like
public unsafe override int GetHashCode()
{
	fixed(float * fp = m) {
		int * ip = (int *) fp;
		return ip[0] ^ ip[1] ^ ip[2] ^ ip[3];
	}
}