Take the 2-minute tour ×
Geographic Information Systems Stack Exchange is a question and answer site for cartographers, geographers and GIS professionals. It's 100% free, no registration required.

I have a series of polygons which overlap in spatialite. Each has a an attribute providing it's z-order as well as the output color for that polygon. What do I need to do, processing-wise, to allow SharpMap to display the polygons based on z-order, along with the proper color for each polygon, all in a SINGLE layer?

share|improve this question
add comment

1 Answer

You would first need to tweak the SpatiaLite provider by either

  • add a OrderBy property and apply that to the relevant queries (GetGeometriesInView, ...), or
  • update the provider to handle spatial views correctly.

Then you need to apply a custom theme setting assigning the appropriate color in respect to ZOrder.

Why don't you want several layers?

Hth FObermaier

share|improve this answer
    
Thank you for the informative response. Custom theme is no problem. I will have a large number of layers if I did not preprocess the data. I need a very fast rendering methodology for the sharpmap part of the process and I'm trying to avoid cutting up the polygons so that only the non overlapping parts are available in the layer. –  WayneF Feb 17 '12 at 23:37
add comment

Your Answer

 
discard

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

Not the answer you're looking for? Browse other questions tagged or ask your own question.