Ticket #3876 (new enhancement)
UTM class to support other TM based national grids
| Reported by: | Polarbear | Owned by: | team |
|---|---|---|---|
| Priority: | normal | Component: | Core |
| Version: | Keywords: | UTM, national grids | |
| Cc: |
Description
It would be good if support for national TM projections could be considered in the generic UTM implementation currently going on.
This might be as simple as providing an interface for some core parameters.
E.g. I successfully hacked the current UTM 33 stub by using 8.0 as the centre meridian, and suddenly all my Irish TM references were orthogonal...
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Change History
comment:2 Changed 2 years ago by Polarbear
currently in UTM.java, the zone and the UTMScaleFactor are wired at the beginning of the class implementation, while the UTMCentralMeridianDeg is computed from the zone.
National TMs can have scale factors, central meridians and true/false origins different from UTM, for example http://en.wikipedia.org/wiki/Irish_Transverse_Mercator#Comparison_of_ITM.2C_Irish_Grid_and_UTM
As I assume the core calculation is the same I thought all parameters could be kept adjustable.
In other words, keeping the generic TM calculation separate from the UTM specifics.



Well, theoretically setting the meridian is already implemented, only currently the values are ignored when initializing the class. I had no time yet to fix that issue. Mainly it is to read and use the first value of the list given as argument (including validity checks).