Swipe up to add points.

Press 'w', press the up arrow, or scroll up to add points and to hide this menu.

Swipe down to remove points.

Press 's', press the down arrow, or scroll down to remove points.

Points are added and removed gradually.
If the line is green then points are being added.
If the line is purple then points are being removed.

Tap to reset the speed of points.

Click to reset the speed of points.

Tap and hold to reset everything.

Click and hold to reset everything.

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