The tolerance forms the radius of a circle. The circle is centred over each point of the line in turn and any points that fall within the circle are deleted.
In this example, the circle is first centred on the starting point of the line.
No points fall within the circle so it is moved to point B.
Again, no points fall within the circle, so it is moved to point C.
Points D and E fall within the circle so they are deleted. The circle is moved to point F.
Points G and H fall within the circle so they are deleted. The circle is moved to point I.
No points fall within the circle.
No more points can be removed. The simplified line looks like this:
