This project implement a variation of the DeBerg line simplification algorithm.
The algortithm enables you to simplify lines without introducing self-intersections. You can also define an additional set of points that will stay consitent with regard to the line simplification: They will not change the 'side' of the line (e.g. when simplifying country borders cities will not suddently be in different countries).
This variation always computes the strongest simplification possible using the fewest edges.
All dependencies (other than boost) should be included in third_party/.
mkdir build
cd build
cmake .. -DCMAKE_BUILD_TYPE=Release
make
./deberg MAX_NUMBER_EDGES lines.txt points.txt output_lines.txt
Will write the result in output_lines.txt and print number of used edges in the console.
osm-admin-bounds is a tool to generate the input data from OpenStreetMap data.
You can use utils/data_to_geojson.py to convert files to geojson for easy visualization.
id:graphml_string
Example:
1:<gml:LineString srsName="EPSG:54004" xmlns:gml="http://www.opengis.net/gml"><gml:coordinates decimal="." cs="," ts=" ">-7984749.593824852,5368675.690126911 -7984392.035620423,5367570.791302501 -7983220.843257783,5366848.500158152</gml:coordinates></gml:LineString>
id:graphml_string
Example:
115:<gml:Point srsName="EPSG:54004" xmlns:gml="http://www.opengis.net/gml"><gml:coordinates decimal="." cs="," ts=" ">-7878323.0399299,5218629.93044479 </gml:coordinates></gml:Point>
Same format as lines.txt.