Even when using anti-aliased rendering it is sometimes possible to see pixel artifacts on the screen. The artifacts are most prominent when your line or curve is nearly, but not quite horizontal or vertical. The effect is subtle, but it can be annoying, especially when you draw with a very thin line. A thin line has no 'body' to distract your from the edges. ZeusDraw's new SoftEdge rendering removes most of these artifacts. In the picture below, the upper line and the upper arc are drawn normally, while the lower line and the lower arc have Soft Edges.
The next picture is the same, but magnified by a factor of two so that you can see the effect more clearly. This is what things would look like if your screen pixels were twice as big as they actually are.
Using ZeusDraw's soft edges can make freehand drawing on the screen a more pleasant experience with more of the feel of drawing on real paper. The gentleman on the right is clearly a much smoother guy.