Actually it's quite simple. We parse from left to right. When we hit EOL, we return to the beginning of line and increase Y by one. Blocks are parsed in the fo

Actually it's quite simple. We parse from left to right. When we hit EOL, we return to the beginning of line and increase Y by one. Blocks are parsed in the following way: when we get the beginning count of block opening characters, we move Y by one, loop right while whitespace, until we encounter ending count of block characters. In transposed block, we just switch X and Y, it is easily done with pointers, and use the same code.