I'm looking for a program that makes an animated gif with loop and seamless, suggest any?
I did this using Flash 8, but it's a lot of work
http://construct2.96.lt/gifs/1loop_offset_gif_teste.html
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Couldn't you make it in Construct, and save a series of png files and use something else to convert them to a gif?
Making the gif directly could be possible from javascript but there is nothing setup for that currently.