|A rounded nonuniform spline|
As you can see, it is a relatively-smooth shape, despite the fact that I've turned it into line segments roughly ten pixels long each. A second spline is shown below, selected so that the end points of the line segments are visible.
|A spline selected. The green circles represent the end points of the line segments.|
So what's next, in the immediate future? The polyline with curved corners, and making the edit mode display the vertices as drawn, rather that the line segment vertices. Pan and zoom, too. Then comes the real work, with the substances/layers. Road, rail, river, etc. Stay tuned for more.