[Mapserver-users] Display polygon layer as circle layer

Mon Jul 14 06:38:43 PDT 2003

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Dear all,

I have some (polygon) layers containing national statistics (for example 
GDP or Population Density). They are nicely displayed in five categories, 
represented by different colors. Now, I would like to place another, 
geospatial (e.g. land cover, DEM) layer under it. I can change the 
transparency of the statistical layer, but the result is not very nice. It 
is too difficult to recognize the correct category, as the two layers are 
becoming too blurry.

Now I thought perhaps it would be more meaningful if I would overlay the 
geospatial/background image with a "circle-layer", instead of a 
"polygon-layer". The size or the color of the circles would represent then 
the value of the country. This would leave enough space to see the 
background image, but one could still recognize the different categories of 
the statistical layer.

Is there a simple way to accomplish this? Do I have to create from the 
polygon shapefile a point shapefile on-the-fly, before then displaying the 
latter?

Thanks for any help,

Stefan

         _______________________________________

         Stefan Schwarzer
         Consultant on GEO

         UNEP/DEWA/GRID-Geneva
         Chemin des Anemones 11
         CH - 1219 Chatelaine
         Switzerland

         Tel: (+41) 22.917.83.49
         Fax: (+41) 22.917.80.29

         Email: stefan.schwarzer at grid.unep.ch
         Internet: http://geodata.grid.unep.ch/
         _______________________________________ 
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Dear all, 
I have some (polygon) layers containing national statistics (for example
GDP or Population Density). They are nicely displayed in five categories,
represented by different colors. Now, I would like to place another,
geospatial (e.g. land cover, DEM) layer under it. I can change the
transparency of the statistical layer, but the result is not very nice.
It is too difficult to recognize the correct category, as the two layers
are becoming too blurry. 
Now I thought perhaps it would be more meaningful if I would overlay the
geospatial/background image with a "circle-layer", instead of a
"polygon-layer". The size or the color of the circles would
represent then the value of the country. This would leave enough space to
see the background image, but one could still recognize the different
categories of the statistical layer. 
Is there a simple way to accomplish this? Do I have to create from the
polygon shapefile a point shapefile on-the-fly, before then displaying
the latter? 
Thanks for any help, 
Stefan 
 
<x-sigsep></x-sigsep>
<x-tab>        </x-tab>_______________________________________ 
<x-tab>        </x-tab>Stefan
Schwarzer 
<x-tab>        </x-tab>Consultant
on GEO 
<x-tab>        </x-tab>UNEP/DEWA/GRID-Geneva 
<x-tab>        </x-tab>Chemin des
Anemones 11 
<x-tab>        </x-tab>CH - 1219
Chatelaine 
<x-tab>        </x-tab>Switzerland 
<x-tab>        </x-tab>Tel: (+41)
22.917.83.49 
<x-tab>        </x-tab>Fax: (+41)
22.917.80.29 
<x-tab>        </x-tab>Email:
stefan.schwarzer at grid.unep.ch 
<x-tab>        </x-tab>Internet:
<a href="http://geodata.grid.unep.ch/" eudora="autourl">http://geodata.grid.unep.ch/</a> 
<x-tab>        </x-tab>_______________________________________</body>
</html>

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