Blog

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

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

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

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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Fun Stuff: Computing circular buffers in geographic coordinates

Finding all the objects within a certain distance from a point is surely a common GIS problem. The problem is normally solved using OGC "dwithin" filters or by computing a buffer and then finding all the intersecting objects. Very often both of the approaches fail miserably in case the coordinate system is a geographic one, as common libraries, such as JTS and GEOS, are not able to handle the non planar nature of it. As far as "dwithin" is concerned rencent Oracle and PostGIS versions can manage the problem properly, but what to do if they cannot be used?We had...

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(CAS + LDAP + FTP + LifeRay) ^ GeoSolutions = Enteprise Portal

Recently GeoSolutions has developed for one our biggest clients their new web portal . The long term goal was to rationalize and concentrate all users and applications management in a single entry point, providing them with all the functionalities of a classic web portal.Use Case and RequirementsThe development and deployment of the whole architecture was challenging due to the strict functional and non-functional requirements they put forward.The use case is quite complex since our client periodically conducts experiments at sea, collaborating with other agencies and research centres, where large amounts of data are collected and stored. Moreover, security is a crucial...

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