From ilike2Flash – Pendulum swing effect in Actionscript 3:
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In this tutorial you will learn how to create a Pendulum swing effect in Actionscript 3. A pendulum effect is where an object continually swings horizontally back and forth. To achieve this effect I have used the Math.sin() function. Firstly, if you have ever seen a graphical representation of a Sine wave, you see that it goes smoothly left to right from the angles 0 to 360. The value at 90 degree is 1 and at 270 degree is -1. The Sin wave moves smoothly from 1 to -1. So, instead of going from the values 1 to -1 over again, we can multiple those values by a greater value, for example, 45, which will give values from 45 to -45. These values can then be set to the rotation property of a movie clip to give a smooth swinging motion from left to right…
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