#Linux imagemagick draw circle archive
#Linux imagemagick draw circle code

The animation with an inner and outer loop of different sizes was created by setting the number of loops to 15 and leaving the number of turtles at 23 (too low to represent 15 loops). I've hidden the explanation of this one below in case anyone wants to delay finding out while experimenting/thinking. In particular the image further up which has a slow outer loop and a fast inner loop (the one that looks like a cardioid that someone accidentally dropped). It might not be immediately obvious how the images above were all produced from this same code. I've left my main example above without flip as I prefer not to have the sporadic jump, but the edge of the circle does look smoother with all the turtles aligned, so the option is there for people to choose whichever style they prefer when running the code. lines if non-zero displays the lines on which the turtles move, for consistency with the example image in the question.Įxamples with flip set, with and without lines.As default they keep a fixed direction to avoid the visual distraction at the endpoints. flip if non-zero causes the turtles to flip direction for their return trip (as suggested by aslum so that they are never moving backwards).The default of 1 gives a standard circle, other odd numbers give that number of loops in the string of turtles, while even numbers give a string of turtles disconnected at the ends, but still with the illusion of curved motion. loops determines how many times the turtles loop back on themselves.resolution is the time resolution (number of animation frames per repetition).

#Linux imagemagick draw circle code

The code can be run with 5 optional arguments: population, resolution, loops, flip and lines. If pi / 2 < individual_phase <= 3 * pi / 2:ĭistance = radius * sin(individual_phase)Ĭircle_dance(*(float(n) for n in sys.argv))įor contrast here are some that really do rotate: Individual_phase = (phase + i / population * loops * pi) % (2*pi) Return random() * 0.9, 0.5 + random() * 0.5, random() * 0.7ĭef animate(turtles, resolution, screen, loops, flip, radius):ĭelay = 4 / resolution # 4 seconds per repetitionĭraw_dancers(turtles, phase, screen, loops, flip, radius)ĭef draw_dancers(turtles, phase, screen, loops, flip, radius): Turtles = Īnimate(turtles, resolution, screen, loops, flip, radius) import turtleĭef circle_dance(population=11, resolution=480, loops=1, flip=0, lines=0): Running the code locally gives a smoother animation. The framerate is reduced considerably for all of these GIF examples, but it doesn't seem to detract from the illusion. The illusion still seems quite strong even with just 3 or 4 turtles: Despite this the circle illusion is still strong. The turtles are different colours and they always face in the same direction, so they can be easily seen to be moving along straight lines by just focusing on one of them. drawImage() is a quick helper for debug output (see code comments) to help you reproduce the process. This example creates a circle, one part green, one part red using kind of masks for transparency, which you might know from Photoshop.

#Linux imagemagick draw circle archive

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