WorldToEcef and EcefToWorld free functions

Summary

GeocentricTransform<TDirectionOfMapping, TScalarType> is a otb::Transform that can be used to transform geographic points to and from ECEF points.

In some cases it is interesting to perform the conversion without having to instantiate a transform object, for example if only one conversion is required. This MR implements otb::Projection::WorldToEcef and otb::Projection::EcefToWorld as free function. These functions are used internally by GeocentricTransform

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Implementation Details

The functions are implemented in Modules/Core/Transform/GeocentricTransform.h/hxx and are templated over the scalar type and over a struct holding the ellipsoid parameters used for the computations. By default the WGS84 ellispoid parameters (new struct otb::Projection::WGS84Ellispoid) are used. Prior to this merge request, these parameters were stored in GeocentricTransform

Additionally, this MR removes useless map projection instantiation in the GeocentricTransform constructor, which is now defaulted.

Copyright

The copyright owner is CNES and has signed the ORFEO ToolBox Contributor License Agreement.

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changed milestone to %8.0.0

added refactoring label

assigned to @ctraizet

added 1 commit

• 530141f4 - DOC: fix typo and add more documentation for WGS84Ellipsoid

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changed title from WorldToEcef and EcefToWorld free function to WorldToEcef and EcefToWorld free functions

mentioned in issue remote_modules/diapotb#7

added Ready for review label

changed the description

added 1 commit

• c500fa5b - PERF: optimize WorldToEcef and EcefToWorld (code review)

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resolved all threads

resolved all threads

added 1 commit

• 44bd316e - PERF: More optimaztions of WorldToEcef and EcefToWorld (code review)

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mentioned in commit cb134b4f

merged