More Varieties on different boundaries

[liangchen76]

I like the variation of boundary thickness. How about more varieties like transparency, dash line, dotted line or etc.? On some cases, the state boundary is displayed as a thick dash line. This is something to think about.

[scrollie]

Unfortunately, because of the data, it is very difficult for us to use dotted or dashed lines (we tried). The issue is that, instead of having the boundaries stored as a multiline, the states are stores as individual polygons with boundaries of adjacent states overlapping. As a result, applying a dash is difficult because it is drawn twice such that, for example, the border of PA and MD has two overlapping dashed lines that appear irregularly dashed.

This could be mitigated by modifying the underlying data, but we've been hesitant to create derivative datasets because we don't want to create maintenance issues on Nielsen's end. Is this something we should pursue?

[mpriour]

@scrollie is correct, this is a limitation of the way that geotools renders polygon outlines and not possible without some serious data reprocessing. See the transcript of Andreas Aime's response to the dashed polygon question

<mpriour> aaime, dwins : do either of you know if there is a way to force geotools rendering to synchronize the dash line pattern for coincidental line segments?
<aaime> not that I know of
<aaime> we just tell java2d "draw with dash" and there it goes
<aaime> we have little control over how it does it
<mpriour> so you can't practically use dashed lines for polygons, if they share topology with other polygons, then?
<aaime> not as polygons
<aaime> you should extract the boundary network, break it where they touch, remove the overlapping sections
<aaime> it's hard processing
<aaime> not something you can do while rendering
<aaime> you basically have to build a topology out of the polygons
<aaime> it's also rather error prone
<aaime> given that the data sources are not topological
<mpriour> ok, well that is not the answer I was hoping for, but it is good to know. thanks aaime

[iwillig]

Since we have mostly addressed this issue I am going to close it for now.