PNGMask.ISAAC.Isaac C# (CSharp) Method

        public void Isaac()
        {
            int i, j, x, y;

            b += ++c;
            for (i = 0, j = SIZE / 2; i < SIZE / 2; )
            {
                x = mem[i];
                a ^= a << 13;
                a += mem[j++];
                mem[i] = y = mem[(x & MASK) >> 2] + a + b;
                rsl[i++] = b = mem[((y >> SIZEL) & MASK) >> 2] + x;

                x = mem[i];
                a ^= (int)((uint)a >> 6);
                a += mem[j++];
                mem[i] = y = mem[(x & MASK) >> 2] + a + b;
                rsl[i++] = b = mem[((y >> SIZEL) & MASK) >> 2] + x;

                x = mem[i];
                a ^= a << 2;
                a += mem[j++];
                mem[i] = y = mem[(x & MASK) >> 2] + a + b;
                rsl[i++] = b = mem[((y >> SIZEL) & MASK) >> 2] + x;

                x = mem[i];
                a ^= (int)((uint)a >> 16);
                a += mem[j++];
                mem[i] = y = mem[(x & MASK) >> 2] + a + b;
                rsl[i++] = b = mem[((y >> SIZEL) & MASK) >> 2] + x;
            }

            for (j = 0; j < SIZE / 2; )
            {
                x = mem[i];
                a ^= a << 13;
                a += mem[j++];
                mem[i] = y = mem[(x & MASK) >> 2] + a + b;
                rsl[i++] = b = mem[((y >> SIZEL) & MASK) >> 2] + x;

                x = mem[i];
                a ^= (int)((uint)a >> 6);
                a += mem[j++];
                mem[i] = y = mem[(x & MASK) >> 2] + a + b;
                rsl[i++] = b = mem[((y >> SIZEL) & MASK) >> 2] + x;

                x = mem[i];
                a ^= a << 2;
                a += mem[j++];
                mem[i] = y = mem[(x & MASK) >> 2] + a + b;
                rsl[i++] = b = mem[((y >> SIZEL) & MASK) >> 2] + x;

                x = mem[i];
                a ^= (int)((uint)a >> 16);
                a += mem[j++];
                mem[i] = y = mem[(x & MASK) >> 2] + a + b;
                rsl[i++] = b = mem[((y >> SIZEL) & MASK) >> 2] + x;
            }
        }

        protected static ISAAC PrepareISAAC(byte[] seed)
        {
            ISAAC rnd = new ISAAC();

            rnd.Isaac();
            for (int i = 0; i < ISAAC.SIZE; i++)
            {
                rnd.mem[i] ^= seed[i % seed.Length];
            }
            for (int i = 0; i < 3; i++)
            {
                rnd.Isaac();
            }

            return(rnd);
        }