In Primer of Visual Literacy (DD) read pp. 0-37. Using DBN, create a perceptual glitch, i.e. a visual illusion. Your illusion should be constructed by reusing at least 1 similar part via use of the 'command' command in Chapter 12 of the DBN book.

// which box is bigger?

Command Box L D R U
{
   line L D R D
   line L U L D
   line R D R U
   line R U L U
}
paper 100
pen 0
Box 20 40 40 60
Box 22 42 38 58

repeat A 0 100
{
   line 50 A 100 A
}
pen 100
Box 60 40 80 60
Box 58 38 82 62

command spikes
{
   command triangle H1 V1 H2 V2 H3 V3
   {
      line H1 V1 H2 V2
      line H2 V2 H3 V3
      line H3 V3 H1 V1
   }
   pen 38

repeat f 5 0
{
   triangle 0 50 (f*10) 20 (f*10) 80
}

   repeat f 5 0
   {
      triangle 100 50 (f*10+50) 20 (f*10+50) 80
   }

}
spikes