Context Free Art cfdg version 3 ( A charcoal drawing?)

// original by bluesky translated for CF3 

startshape trunk
CF::Size = 1280, 1024
CF::ColorDepth = 16
CF::Color = 0
shape trunk
{ branch [s .5 b 0   h 20 sat 0 ]  }

shape branch
rule { branch [r 30  ] }
rule 0.01 { line [] }

shape line
{loop 300  [[r .1 x 2]] dot [] }

shape dot
rule { dot [y .1  ]  }
rule { 
  trail [ r 90 ] 
  trail[] }
rule 0.002 {line [r 90 h 0 ]  }
rule 0.002 {branch [r 90 h 30]  }
 
shape trail
{ loop 200 [[y 2 a -0.02]] grain [a -.1] }

shape grain
{ gr [] }

shape gr
rule { gr [ x 1 ] }
rule { gr [ x -1] } 
rule {SQUARE []}

As a Movie:-
ffmpeg -f image2 -i %3dcharcoal.png movie.mp4