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https://issues.apache.org/jira/browse/SIS-51?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Martin Desruisseaux updated SIS-51:
-----------------------------------
    Fix Version/s:     (was: 0.5)

> Pluggable Distance Calculation
> ------------------------------
>
>                 Key: SIS-51
>                 URL: https://issues.apache.org/jira/browse/SIS-51
>             Project: Spatial Information Systems
>          Issue Type: Improvement
>          Components: Referencing
>            Reporter: Peter Karich
>            Priority: Minor
>   Original Estimate: 2h
>  Remaining Estimate: 2h
>
> The distance calculation is done in several places. I think it shouldn't be a 
> static helper method instead it should be an instance which could be replaced 
> by a more precise or faster calculations:
> double distance(double latFrom, double lonFrom, double latTo, double lonTo)
> E.g. one could use euclidean distance, haversine calculation or a fast 
> projection calulation 
> (https://github.com/karussell/GraphHopper/blob/master/core/src/main/java/de/jetsli/graph/util/ApproxCalcDistance.java
>  + see test). 
> Also one should think about "normed" distances. I mean, if one does not need 
> the actual distance and rather needs to compare distances one could avoid 
> parts of the distance calculation and make it faster. e.g.:
> sqrt(deltaX*deltaX + deltaY*deltaY) then gets: deltaX*deltaX + deltaY*deltaY 
> and the comparisons of distances are still correct if done for all distances 
> (eg. in a quad-tree). This could be done with a separate normedDistance 
> method or probably just the same and a different implementation? Not sure ...



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