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2020-09-30Add a +proj=tinshift for triangulation-based transformationsEven Rouault
Implements RFC-6
2020-05-16Add a +proj=defmodel transformation for multi-component time-based ↵Even Rouault
deformation models Fixes #1001 Co-authored-by: Chris Crook <ccrook@linz.govt.nz>
2020-01-22Merge RFC4 (#1865)Even Rouault
This commit is the result of the squashing of rfc4_dev branch in a single commit. It implements mostly RFC 4 related work. * Grid handling: - remove obsolete and presumably unfinished implementation of grid catalog functionality - all grid functionality is in grids.cpp/.hpp - vertical and horizontal grid shift: rework to no longer load whole grid into memory - remove hgrids and vgrids member from PJ structure, and store them in hgridshift/vgridshift/deformation structures - build systems: add optional libtiff dependency. Must be explicitly disabled if not desired - add support for horizontal and vertical grids in GeoTIFF, if libtiff is available - add GenericShiftGridSet and GenericShiftGrid classes, relying on TIFF grids, that can be used for generic purpose grid-based adjustment - add a +proj=xyzgridshift method to perform geocentric translation by grid. Used for French NTF to RGF93 transformation using gr3df97a.tif grid - deformation: add support for +grids= for GeoTIFF grids - horizontal grid shift: fix failures on points slightly outside a subgrid (fixes #209) * File management: - add a filemanager.cpp/.hpp to deal with file related work - test for legacy proj_api.h fileapi - proj.h: add proj_context_set_fileapi() and proj_context_set_sqlite3_vfs_name() (fixes #866) - add capability to read resource files from the user writable directory * Network access: - build systems: add optional curl dependency - add a curl-based default implementation for network related functionality - proj.h: add C API to control network functionality, and optionaly provide network callbacks - add data/proj.ini with default settings - add a SQLite3 local cache of downloaded chunks - add proj_is_download_needed() and proj_download_file() * Use Win32 Unicode APIs and expect all strings to be UTF-8 (fixes #1765) For backward compatibility, if PROJ_LIB content is found to be not UTF-8 or pointing to a non existing directory, then an attempt at interpretating it in the ANSI page encoding is done. proj_context_set_search_paths() now assumes strings to be in UTF-8, and functions returning paths will also return values in UTF-8.
2018-10-27Implement Molodensky-Badekas transform (fixes #1160)Even Rouault
2018-10-12Add docs for the horner operationKristian Evers
2018-10-01Add a affine transformation method, and make geogoffset as a particular case ↵Even Rouault
of it (fixes #535)
2018-10-01Add geographic offset transformation method.Even Rouault
The Geographic offsets transformation adds an offset to the geographic longitude, latitude coordinates, and an offset to the ellipsoidal height. This method is normally only used when low accuracy is tolerated. It is documented as coordinate operation method code 9619 (for geographic 2D) and 9660 (for geographic 3D) in the EPSG dataset. It can also be used to implement the method Geographic2D with Height Offsets (code 9618) by noting that the input vertical component is a gravity-related height and the output vertical component is the ellispoid height (dh being the geoid undulation). It can also be used to implement the method Vertical offset (code 9616) It is used for example to transform: - from the old Greek geographic 2D CRS to the newer GGRS87 CRS - from Tokyo + JSLD69 height to WGS 84 - from Baltic 1977 height to Black Sea height It is also useful to document the implicit zero-offset transformation we do in pipelines such as +proj=pipeline +step +inv +proj=longlat +ellps=A +step +proj=longlat +ellps=B that can be explicited as +proj=pipeline +step +inv +proj=longlat +ellps=A +step +proj=geogoffset [+dlon=0 +dlat=0 +dh=0] +step +proj=longlat +ellps=B
2018-02-28Move 'Coordinate operations' to top level of docs [skip ci]Kristian Evers