Geographic Information Systems Stack Exchange is a question and answer site for cartographers, geographers and GIS professionals. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Is there a general format (standards based) to store a vector based drawing description for multipoint symbology (means having several anchor points reflecting symbol point <-> geographic point association)?

OGC defined the Styled Layer Descriptor which uses symbolizers (point/line/polygon) but one problem is that they are better suited to be created for a single point representation (to place e.g. a raster based symbol at specific location, maybe with offset) or the have a stronger dependency to the geometry (following a line with an offset, placing somthing at the line, ...) like a line/polygon symbolizer.

If you look at the mil2525c standard there are several symbols where the graphical representation has nothing in common with the stored geometry except the anchor point association to "stretch" the symbol.

So I expect those problems using OGC conformant aproach using sld:

  1. I don't see any default "multipoint" symbolizer, only a point symbolizer, a line symbolizer and a polygon symbolizer. Line and polygon symbolizers both don't fit because they only styles the line/polygon geometry ( => abstaction to mil2525c multipoint geometries and styling them using sld would be very complex... not to say impossible.)

  2. Point symbolizer can call a mark factory (e.g. see GeoTools interface/implementation docs at to get a shape instead of a raster based symbol but there is no general approach to handle anchor points in a default manner.

  3. If using the 2nd. approach using a point symbolizer: The problem of storing vector based data for symbology generation is not solved. ("Hand-made" generation by building the geometry seems to be an option, but is difficult to analyse or edit. What type is shape in the .net world or what would be the "universal" equivalent (System.Windows.Shapes.Path)?

Are there other standards for multipoint symbols I didn't noticed? How would you solve this problem?

share|improve this question

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.