Symbology: import from and export to other systems

[tjasz]

While one of the primary differentiators for geotab is its ability to define the symbology of map features by sets of rules based on multiple feature properties, it is also useful to export the calculated symbology to other systems in a way that they understand. The calculated symbology should be included during export (when exporting to non-geotab formats). The export options need to include the symbology format (or maybe it's part of the file format).

For example, caltopo appears to use SimpleStyle, where a handful of style properties are included in the GeoJSON features' properties. It may be slightly different though, as its not made explicit. Export several examples of points, lines, and polygons with various styles to be sure.

GeoJSON+CSS has a style attribute in the feature objects.

GPX also has extensions for symbology.

KML also defines display properties.

[tjasz]

CalTopo mostly seems to use SimpleStyle, but additionally has a "pattern" property to specify the SVG used for the line strings.

[tjasz]

Somewhat useful note while working this issue: here are the SVG path style options available on vector layers.

[tjasz]

For import: I suppose styles from GPX and KML should be converted to simple style. Then, if simple style, CalTopo patterns, or GeoJSON+CSS are defined and geotab symbology is not, the styles defined by those specs should be used.

Question: even if geotab symbology is defined, should simple style and GeoJSON+CSS override it?