This is the options Quick Reference

Options syntax:

   # The '#' marks a comment line
   LENGTH    <Distance>
   DISTANCE  <Euclidian distance>
   BLIND     <Sector>  <Distance>
   LINE      <Line no>
   LEFT      <Line no>
   RIGHT     <Line no>
   BLOCK     <Line no> <Line no>
   ONE       <Line no> <Line no>
   SAFE      <Sector>  <Distance>
   INV SAFE  <Sector>  <Distance>
   INV BLIND <Sector>  <Distance>
   REPORT    <Distance>
   PERFECT

<Distance> The distance is the number of sectors between two sectors
   Counted in a strange way. For instance if you want the monsters in
   a sector to be totally blind use 'BLIND <Sector> 0'. If you want them
   to be able to see their own sector use 'BLIND <Sector> 1',
   for neighbours use 2 and so on.

<Euclidian distance> is the distance in 1/10 th of meters (intuitively)
   that monsters can see.

<Line no> Is the number of a TWO SIDED line. This line number can be found
   using almost every WAD builder. (DEU5.21 recommended)

<Sector> is the number of a sector. can also be found
   by the same WAD builder.

a brief explanation: (sorted alphabetically)

*  BLIND     Specifies the distance a monster can see (near sighted)
   BLOCK     Monsters can't look through BOTH 2s lines (One is ok)
   DISTANCE  Makes all monsters unable to see further than this.
*  INV BLIND Specifies that monsters can only see outside the distance.
*  INV SAFE  Monsters can't see this sector inside the distance.
   LEFT      Makes a 2s line that can only be looked through left to right.
   LENGTH    Specifies the max # of sectors any monster can see.
   LINE      Makes a 2s line impossible to look through for monsters.
   ONE       Same as block, but only stops LOS one way.
   PERFECT   Generates a perfect reject map.
   REPORT    Reports all detected distances >=<distance> to <wad file>.RPT
   RIGHT     Makes a 2s line that can only be looked through right to left.
*  SAFE      Monsters can't see this sector outside the distance.

Options marked by * indicates that BLIND and SAFE gets
special meanings when combined with INV BLIND and INV SAFE (respectively)
for the same sector.