Hi,

The other side is that hand written extents tend to go wrong every now and 
then, layer data and extents may change over the time, and for some data 
sources it is not heavy at all to read the extents on-the-fly. But big database 
tables without up-to-date statistics and Oracle in general can be awfully slow.

-Jukka Rahkonen-

Seth G wrote:


Thanks Tanya.

I'm going to run a few tests with a database connection to see what queries are 
generated to calculate the layer extents for WMS/WFS, and then may make a 
suggestion to update the MapServer docs.

Seth

On 02/11/2016 22:12, TC Haddad wrote:
Hi Seth,

I do agree that it should be *highly* recommended to set the extents of each 
LAYER, as people are often unaware what a huge speed advantage it is to have 
this already set. I found it to be particularly true for WFS.

I believe you should set the layer extents in the native coordinates of the 
layer, and let Mapserver take it from there.

Tanya

On Wed, Nov 2, 2016 at 11:38 AM, Seth G 
<[email protected]<mailto:[email protected]>> wrote:
Hi all,

A draft tutorial has been completed on use of projections in MapServer: 
https://geographika.github.io/tutorial/quickstart/projections.html
Comments and feedback welcome. This relates to 
http://mapserver.org/development/rfc/ms-rfc-115.html

There are a couple of things I came across that are still unclear to me 
relating to extents.

  *   Setting the EXTENT for a map has no effect when accessing via WMS, apart 
from the BoundingBox of the GetCapabilities metadata. Data is not 
restricted/limited.Not setting this leaves the MAP level BoundingBox extent as 
-1,-1,-1,-1. Should the MAP EXTENT have any other effects?

  *   The help for LAYER EXTENT states "In most cases you will not need to 
specify this, but it can be used to avoid the speed cost of having MapServer 
compute the extents of the data" - however all BoundingBox extents for each 
layer are automatically calculated from the source data in the WMS 
GetCapabilities request. I presume this could become quite slow with more and 
more layers. Is it/should it be recommended to manually set these (either with 
wms_extent in the LAYER METADATA or using LAYER EXTENT)?

Thanks for any clarifications on the above.

Regards,

Seth
--
web: http://geographika.co.uk
twitter: @geographika

_______________________________________________
mapserver-users mailing list
[email protected]<mailto:[email protected]>
http://lists.osgeo.org/mailman/listinfo/mapserver-users



_______________________________________________
mapserver-users mailing list
[email protected]
http://lists.osgeo.org/mailman/listinfo/mapserver-users

Reply via email to