Page 6 of 17	  CONTINUOUS ROTATION AND OPTICAL ILLUSIONS

If you want the object to continue rotating without having to hold down an
arrow key, you can press the C key for continuous rotation.  The object will
keep rotating after you release the arrow keys whenever rotation is the current
motion.  To turn off continuous rotation, press the C key again.

You may have already noticed a common optical illusion.  The object seems to be
rotating in one direction, then suddenly appears to reverse.  One reason for
this is that for wire frame objects under an orthogonal projection (the mapping
that AcroSpin uses to represent a 3-D object on your 2-D computer screen), the
direction of rotation is ambiguous, and our brains sometimes flip between the
two possible interpretations.

You can practice using the C key, and look for the optical illusion, on the
next object, a bedroom.

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