animated gifs of (sorting) algorithms

Question

What is the best way to generate gifs of algorithms like this one in Wikipedia? In Linux, any language really.

Answer 1

ImageMagick can construct animations by assembling several bitmaps into one:

convert -delay 100 \
      -page first.gif \
      -page second.gif \
      -page third.gif \
      -loop 0  animation.gif

Answer 2

There are probably more user-friendly ways, but last time I did this, I used gifsicle to assemble some pre-built frames into an animation.