
I've been working on rendering coastlines - I think I've finally sorted it out. Drawing coastlines made up of ways that are not closed polygons, when there are many possibilities of how they can be arranged, and including islands and lakes has been tough. It has forced me to revisit some long forgotten maths, including calculating cross products of line segments to decide if a closed way turns clockwise or anti-clockwise.
These two pictures show tiles with fairly complex coastlines drawn accurately - the Pacmen are lakes and islands. Making test data with JOSM has been very useful - testing with live data never gives you all the possible circumstances, but it will give me volume data tests later. Text placement next I think.
1 comment:
There's a coincidence for you - I read this just 10 seconds after I'd finished drawing a map for work of the Driffield Navigation!
Post a Comment