[Roadster] sexy rivers

[Ian McIntosh]

Barry,

> I'm sure you could use some sort of smoothing, but you'd need to make 
> sure you don't cause collisions with roads, etc.

I think Roadster shows rivers for two reasons: to aid in orientation,
and to look pretty.  I'm not so sure it matters if rivers go under roads
a bit.  It does happen with the actual data, too.

But-- if we limited the random curves that we added to river lines to
**1/2 the width of the thinnest road at that zoomlevel**, then we
wouldn't risk the river poking out the other side of road (unless the
data already had a point that crossed the road line).

It could be optional; on the list of "pretty or fast?" drawing options.

> Google seems to have much higher-res data though... their river 
> matches the satellite image fairly closely.

Definitely.  But let's work with what we've got!  I think we can make
the Roadster experience better than Google maps.

-Ian