GIS

Developers Corner: Improving GeoTools/GeoServer raster reprojection performance

Blog ‐ Posted on 10.01.2011 by simone giannecchini

Ciao a tutti,we hope everybody had nice seasonal holidays and is back fresh and ready to move on with another year of activity.In this blog we'd like to present some of the work we have been doing in recent time to improve GeoTools and GeoServer raster reprojection abilities. Raster reprojection is a quite heavy process in which every single pixel of the original image has to be mapped into a new position in the target raster. Here is a visual representation of a small set of pixels, before and after the reprojection (in this case, from WGS84 to polar stereographic):...

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Developers Corner: Improving GeoServer security

Blog ‐ Posted on 20.12.2010 by simone giannecchini

Hi,during the last few weeks we have been thinking a lot about improving the GeoServer security, making it at the same time easier to integrate with external authorization systems and making it more expressive in terms of what kind of security rules can be expressed.As part of the work we have been re-evaluating how the security can be applied in an ever growing software like GeoServer without having to cripple the available service abilities or to have to run after the developers constantly adding new features to the system.The evaluation resulted in a (long-ish) comparison of the possible models, including...

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Estimating time and space required to build a GeoWebCache on disk cache

Blog ‐ Posted on 01.12.2010 by simone giannecchini

An outstanding issue when using GeoWebCache is finding out how much disk space a certain layer will use, on disk, once fully cached, and also how much time it will take to pre-seed the cache up until a certain layer.The GeoWebCache site used to link to a Google Documents spreadsheet providing such an estimate, but the link is gone from the current documentation and, regardless, we found the spreadsheet to be less than accurate, basically ending up computing at the very least the seeding size of 1/4 of the entire world no matter how small the given area was.Therefore we...

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GeoServer Tips & Tricks: Auto alignement of labels within polygons

Blog ‐ Posted on 29.11.2010 by simone giannecchini

Labeling polygons can sometimes be tricky. GeoServer ormally places the labels horizontally within the polygon, accepting only labels that "sit" inside the polygon for at least half of their length.However sometimes the polygons just don't collaborate with that setup, they can be thin and long, but rotated on an non horizontal angle: in this case GeoServer would not label them until the user zoomed in quite a bit in the map.Some time ago Björn Hartell and Andrea Aime started working on a patch to add a vendor option auto-rotate the labels for those polygons. After a few iterations and work...

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GeoServer Tips & Tricks: Auto alignement of labels within polygons

Blog ‐ Posted on 29.11.2010 by simone giannecchini

Labeling polygons can sometimes be tricky. GeoServer ormally places the labels horizontally within the polygon, accepting only labels that "sit" inside the polygon for at least half of their length.However sometimes the polygons just don't collaborate with that setup, they can be thin and long, but rotated on an non horizontal angle: in this case GeoServer would not label them until the user zoomed in quite a bit in the map.Some time ago Björn Hartell and Andrea Aime started working on a patch to add a vendor option auto-rotate the labels for those polygons. After a few iterations and work...

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