an Image Magick tutorial by Flo The following results were obtained using Arbor Image Magick. Swirl rotates the center of an image around the degrees of a circle. However, we must remember that the positive numbers rotate the center counter-clockwise; the negative number clockwise. This is just the opposite of the way the Circles and Ellipses in Draw go around the circumference. If we enter 90 into Swirl's parameter box, the center will rotate 90 degrees counter-clockwise. Very little of the central part of the image will be affected. Entering 180 (remember, 180 is halfway around a circle) will rotate the center halfway around from its original orientation. This necessarily has to involve more of the center than did the 90 degrees. Three-quarters around the circle, 270 degrees, involves yet more of the center. And finally, 360 (degrees) makes one complete rotation, involving more of the image's center. Any degrees higher than 360 will start a second rotation around the first one: 720 makes two complete revolutions; 1080 makes a third complete rotation around the first two. From this you can see that the higher the number, the larger area of the image's center will be swirled. EXAMPLES Trace the upper vertical line
Trace the orange (upper) vertical line
I made the upper vertical line orange in the 720 and 1080 swirls, so you can trace it easier. Notice that the lines start to pixelate, even with the 90 swirl, although pixelation isn't really visually prominent until we reach the 360 rotation. For the 720 and 1080 swirls, I started with lines 4 pixels wide. But their break-up is evident anyway. This is not a mistake; this is the "nature of the swirl beast." On to Extreme Swirl
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