refactored my bifurcation diagram (aka orbit diagram) generator to invoke ffmpeg itself, thus adding the ability to encode multiple segments for later seamless repetition to desired length. it's not true "infinite zoom", but a visually indistinguishable fake, and that's good enough for me.
also made it use the z:=z^2+c form, as the distortion of the x:=ax(1-x) form at low zoom levels was annoying me a lot.
these 3 videos rendered in 9mins at 640x360p25 with a density (average number of samples plotted per output pixel) of 1000. I have zoom outs too, and another set of 6 videos zooming to the period 3x island in antenna of period 3x island in antenna of ... limit point are still being rendered.