DWithin filters should honour the units set in the distance element

Unfortunately this goes deep down in Geotools, and it's not trivial

Hi,

Ran into the same issue here too, would really like this to be fixed.
Another option would be that if it doesn't get fixed, it would show some logging information / throwing some kind of not implemented exception...

An approximate version may be implementable given the existing tools. The idea is as follows:

• take the original geometry, sample it over its boundaries and draw a point at the specified distance and using an orthogonal angle to the current line. Making the sampling distance significantly smaller than the to be dwithin distance should provide decent accuracy
• connect all the generated dots and generate a polygon out of it. Mind that this requires the line not to be self intersecting, and there is no guarantee it will be. So some way has to be devised to remove the overlaps
• turn the within distance check into a overlaps check

So, doable it is, but it may not be trivial and there is no resourcing backing this. Are you able to provide it some way? (either your own work or by paying a commercial support provider?)

Ah, just noticed you were not watching the issue. I've added to the watchers list so that you're notified about comments and the like

any progress on this issue?

Hajo, nope, there are ideas on how to do this but the time to implement it is significant, it's not a spare time project

Hey Andrea, whats about JTS.orthodromicDistance as described on http://docs.geotools.org/latest/userguide/library/referencing/calculator.html ?

That is not JTS, GeodeticCalculator is a GeoTools class. Anyways, that computes point to point distance or a target point given a source point, distance and direction.
It's not nearly enough to implement a dwithin or a buffer operation, we lack the concept of nearest points between two non point geometries (which requires the one of minimum point to line distance, which we also don't have).
Regardless, going down this road (precise calculations) would require even more work than the approaches we have in mind and that we did not attempt because.. they are too much work to do in spare time. If skilled java developers at your premises you're welcomed to try and contribute back the changes, if you have funding there is the option of commercial support for GeoTools (http://docs.geotools.org/latest/userguide/welcome/support.html#commercial-support).

Anyways, it's good even if we just discuss it further, whoever gets enough time to actually do this will benefit from reading the conversation logs in this jira.