Introducing the rotator

The scene contains a 'rotator' consisting of a red circle. If you click the red circle, the dart will rotate anti-clockwise about the rotator, in the direction of the arrow. If you right- or shift-click it, the dart will rotate in the opposite direction. Try it.

You can move the rotator by dragging the red drag-point at its centre. Try dragging it somewhere else, then click it to see how it rotates the dart. Practice moving the dart around using the rotator. Try flying it in a figure of eight.

When you have practiced using it, press the Demo button and watch the animation draw a yin-yan symbol. When the viewport becomes white again, try using the rotator to make the dart trace out the symbol. (You can run the demo again at any time by just clicking the demo button.)

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