Rebex.IO.Compression.Deflate.scan_tree C# (CSharp) Метод

        internal void scan_tree(short[] tree, int max_code)
        {
            int n; // iterates over all tree elements
            int prevlen = - 1; // last emitted length
            int curlen; // length of current code
            int nextlen = tree[0 * 2 + 1]; // length of next code
            int count = 0; // repeat count of the current code
            int max_count = 7; // max repeat count
            int min_count = 4; // min repeat count

            if (nextlen == 0)
            {
                max_count = 138; min_count = 3;
            }
            unchecked
            {
                tree[(max_code + 1) * 2 + 1] = (short)0xffff;
            }

            for (n = 0; n <= max_code; n++)
            {
                curlen = nextlen; nextlen = tree[(n + 1) * 2 + 1];
                if (++count < max_count && curlen == nextlen)
                {
                    continue;
                }
                else if (count < min_count)
                {
                    bl_tree[curlen * 2] = (short) (bl_tree[curlen * 2] + count);
                }
                else if (curlen != 0)
                {
                    if (curlen != prevlen)
                        bl_tree[curlen * 2]++;
                    bl_tree[REP_3_6 * 2]++;
                }
                else if (count <= 10)
                {
                    bl_tree[REPZ_3_10 * 2]++;
                }
                else
                {
                    bl_tree[REPZ_11_138 * 2]++;
                }
                count = 0; prevlen = curlen;
                if (nextlen == 0)
                {
                    max_count = 138; min_count = 3;
                }
                else if (curlen == nextlen)
                {
                    max_count = 6; min_count = 3;
                }
                else
                {
                    max_count = 7; min_count = 4;
                }
            }
        }