Emily/Jiwon Curved Road Drawing

[Elliot Conte]

Last week I was inspired by your project to look into the problem of drawing curved roads and I wrote a little program MapDrawer that draws various types of curves based on control points that can be added or deleted.  Unfortunately I can't figure out how to send .exe files through gmail, it doesn't seem to like it.  But I can give it to you via dropbox or something if you have any interest.  My little program draws Bezier Curves and Cubic Spline Interpolated curves through a set of control points the user can add/move/remove.  I believe Bezier curves look best for roads as they always stay within the area bounded by chosen control points and are always very smooth.  I think how it could work is that in your map, users could select to make a curved road then choose control points to define the curve on the grid you already have made.  The curve couldn't be perfectly smooth, but for either type of curve you could just increment the t value, then draw a straight road section from the previous point to the current one.  The t value increment granularity could define the smoothness of the curve and the number of presences used.  

http://en.wikipedia.org/wiki/B%C3%A9zier_curve

http://en.wikipedia.org/wiki/Cubic_interpolation

Unfortunately, this would make it harder to place buildings as the curves would no longer neatly play with your grid of squares.  However, I think a curved road occasionally through a park could make for a much more visually interesting city!  This could also be good for allowing users to define rivers, walls, lake boundaries, mountain/hill ranges, anything you don't want to be perfectly rectilinear.