draw  W px   H px  backgound  R   G   B

 disk  R   G   B    halo  R   G   B

disk radius pixel  halo size - disk size pixel

file name (header name) to auto-save    auto save (no use)

phase shift (0-359)  counter:   number of frames:    backward motion

export GIF animation

(no use)   occluder width pixel  　

Akiyoshi's illusion pages