## Fractal Art Exercise 2

Select the eyedropper and click on the image somewhere near the center. The screen should go mostly, if not all, to the solid color. Put a decimal point before the 1 in the width input box. Now it reads 0.1. If nothing happened, put a zero between the decimal point and the 1, making it 0.01. Keep doing this until you see a (Solid color) stripe. This stripe will be up and down in your fractal.

Now, put the same number in the height box and you’ll have a circle. If you select the rectangle shape, it will change to a square. If you put different values in the height and width, you will get an ellipse or a rectangle instead of a circle or square. If the Rotation Angle of the fractal is not zero, the shape will move in the directions that were originally up and down or sideways.

In other words, if you change the Im value, the shape will move parallel to the stripe you saw earlier. Bigger numbers in the positive direction will cause movement in the direction that was originally up and bigger negative numbers will cause downward movement. In the Re box, positive is right and negative is left.

Now you can make it any size you want by changing the numbers and
put it where you want with the eyedropper. You can rotate it by
entering a value in the Tilt Angle box. If the center you want
is off the screen, click at the edge of the screen and then change
the numbers in the Center box.

I usually put the shape approximately where I want it with the
eyedropper and “nudge” it into the exact position by changing the
numerical values in the input boxes. To find out how to change
the numbers, start at the far right and delete a digit.

If nothing happens, delete another, keep on until you can see the shape move
when you delete a digit. If it moved the wrong way, make the digit
that is now in the last position one bigger; if it moved the right
way and you need more, make it one smaller. There’s no substitute
for experimentation and practice.

> Question…..how do you figure out what numbers to put into the center box
when you use the scissors transformation? Whenever I try numbers or the dropper
the elipse scoots off in what are to me unpredictable directions.

Reverse Scissors, Shapes, Regular Polygons, and Damien’s Clipping all work
essentially the same way as far as positioning is concerned and they all behave predictably
on un-transformed images. Actually, they behave predictably on transformed
images also, but we sometimes lack the facilities for making such complicated
predictions.

As you have no doubt noticed, if you apply any distorting transform such as
kaleidoscope, Unspiral, Lake, etc., etc.; all bets are off. If for example,
you cut a hole in an image and then map it onto an egg, the hole is also mapped.
If, on the other hand, you map an image onto the egg and then cut a hole, the hole is
cut in the image window — not in the egg.

I won’t risk further confusion by discussing what is actually happening — Mark and I batted it back and forth for a
couple of days and Frederik finally gave up on us and intervened. Probably the best way to
think of it is that the transforms appear to work from the bottom up.

This eggsample 😉 shows what I mean. There are three transforms applied. The bottom Scissors is an
ellipse which winds up mapped onto the egg. Its center coordinates are the same as
the Fractal Center on the 3D transform. If you use the eyedropper on it, it will leap
off the screen because the eyedropper is related to the center of the screen which
is a long way from the center of the fractal.

In essence, 3D Mapping lets you have two image windows on top of each other. The first is centered at the center of the
fractal universe and is un-rotated and un-magnified. The center of the fractal
universe is called the origin and its coordinates are (0,0). The second window is sort
of an inset which may be rotated and magnified before mapping it onto the egg and
moving it to the center of screen so you can enjoy it.

UF still “considers” the window to be centered at the origin with a magnification of 1.0 so when you’re looking at
the egg, you’re actually looking at a magnified portion of your fractal a long way
away from the “actual” center. In this example image, the screen would have to be 75
feet across in order to contain both the origin and the image of the egg. It isn’t that
the ellipse moves unpredictably — it’s merely that your screen isn’t big enough to
depict its new position.

The top Scissors is an ellipse centered in the image window. Its center
coordinates are (0,0), the same as the Center on the Location Tab and if you use the
eyedropper on it, it will behave normally. If you click/drag either Scissors to the
opposite of the 3D Mapping transform, the ellipse will “leap” off the screen.

So, the short answer is: if you want to cut a hole through a transformed
image, move Scissors to the top of the transform stack. If you want a hole to appear as
if it is in the transformed image, move Scissors to the bottom of the transform
stack, disable the other transformation and cut the hole wherever you want. Then activate
the other transform.