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2020-12-02Update isea.rstZac Miller
Clarifying defaults for ISEA.
2020-11-20Update utm.rstNomit Rawat
Typo
2020-10-25Add +proj=col_urban projection, implementing a EPSG projection method used ↵Even Rouault
by a number of projected CRS in Colombia (fixes #589)
2020-10-25Fix typos spotted by scripts/fix_typos.shEven Rouault
2020-10-23Minor fixes to tmerc documentationCharles Karney
2020-10-23merc.rst: change "origins from 15th cent" to 16th cent.Charles Karney
2020-10-22merc.rst: revert to ln instead of log.Charles Karney
Also define merc (resp. tmerc) as the conformal projection in which the equator (resp. a chosen meridan} projects to a straight line at constant scale.
2020-10-22Flesh out the documentation for MercatorCharles Karney
This addresses item 1 in issue #2387 Things to note: * I made "editorial" changes to the text. The virtues and vices of Mercator are a hot topic. So check these out. (I judged that the text I replaced to be pretty misleading.) * I include the radius of the sphere/ellipsoid in the formulas (and I did this also for my mods for tmerc documentation). Surely this is better than leaving the reader to figure out how this is introduced. * I include the "old-style" (ca 18th century) formulas and the newer ones in terms of hyperbolic functions. The former may be the familiar ones, but the latter are better for computation (more succinct, more accurate, faster, preserve parity). * For the inverse ellipsoidal transformation, I just say that the formula for psi is inverted iteratively. This is probably sufficient, but it could be expanded later.
2020-10-18Document the default poder_engsager algorithm for tmerc. (#2379)Charles Karney
* Document the default poder_engsager algorithm for tmerc. * Give exact expression for phi' in terms of phi * Aadd another datapoint on range of applicability + explanation for complex numbers. * Update tmerc figure with one reflecting poder/engsager algo. Courtesy of @hobu. Co-authored-by: Charles Karney <charles.karney@sri.com>
2020-10-14Plot building Github Action (#2377)Howard Butler
* implement conda package building * paths * need libtool * PLATFORM check * point to my PROJ feedstock for now * point to PROJ repos * plot building and artifact upload * syntax * add proj conda package for plotting * retab * no doxygen * syntax * update docs Makefile * doc building * needs * consolidate doc/plots * plot updates * put updated plot output into docs * register spelling module * use v2 download-artifact * artifact upload
2020-09-26Implement ellipsoidal formulation of +proj=ortho (fixes #397)Even Rouault
- Map ESRI 'Local' to +proj=ortho when Scale_Factor = 1 and Azimuth = 0 - Map ESRI 'Orthographic' to a PROJ WKT2 'Orthographic (Spherical)' which maps to +proj=ortho +f=0 to froce spherical evaluation
2020-06-03Doc: add specific explanations for lat_ts for +proj=stere, also mentions ↵Even Rouault
+lat_0 and +k_0 (#2255) Refs #2254
2020-05-28Implement wink2 inverse by generic inversion of forward methodEven Rouault
- Move the generic method initiated from adams_ws2 to a pj_generic_inverse_2d() method - Use it in adams_ws2 - Use it in wink2 Fixes https://github.com/qgis/QGIS/issues/35512
2020-05-24Merge pull request #2230 from rouault/limit_peirce_q_to_northern_hemisphereEven Rouault
Limit peirce_q to northern hemisphere, and fix images for adams_hemi, guyou and peirce_q
2020-05-19Zone Definition Fixes for igh_o projection (#2233)John Krasting
- Central lon for zone 2 should be -d10, not d10 - Extra lobe was missing for zone 11 - New figure generated - New test suite values generated
2020-05-19Implemented IGH Oceanic View (#2226)John Krasting
- The current implementation of the Interrupted Goode Homolosine projection emphasizes land area. This is a compliment projection that emphasizes ocean area. - A value of lon0=-160 produces a reasonable real-world map.
2020-05-16plotdefs.json: update validty area for adams_hemi, guyou and peirce_q, and ↵Even Rouault
regenerate associated images
2020-04-28createFromProjString(): handle default parameters of '+krovak +type=crs', ↵Even Rouault
and handle +czech correctly (fixes #2199) (#2200) * createFromProjString(): handle default parameters of '+krovak +type=crs', and handle +czech correctly (fixes #2199) * Doc: add default values for Krovak
2020-04-16Merge pull request #2030 from rouault/auto_sel_of_tmerc_algEven Rouault
tmerc/utm: add a +algo=auto/evenden_snyder/poder_engsager parameter
2020-04-16Implement an iterative inverse method for +proj=adams_ws2Even Rouault
2020-04-15Add square conformal projections from libprojectKristian Evers
This commit adds five new projections to PROJ: adams_hemi: Adams Hemisphere in a Square adams_wsI: Adams World in a Square I adams_wsII: Adams World in a Square II guyou: Guyou peirce_q: Pierce Quincuncial The code originates from Gerry Evendens libproject and has been adapted to work with modern PROJ. To ensure that the modified code works as intended extensive test data has been created using libproject and sproj so that no errors occured when porting from libproject to PROJ. The test data is wrapped in a gie files. All test cases reproduce results from libproject at the mm level.
2020-04-15tmerc/utm: add a +algo=auto/evenden_snyder/poder_engsager parameterEven Rouault
The default remains +alg=poder_engsager. This default value can be changed in proj.ini +algo=auto will use Evenden Synder implementation if the error in doing so remains below 0.1 mm on Earth-sized ellipsoid
2020-03-12Add note about orientation of control pointsB R S Recht
2020-03-11Doc: use 'ellipsoidal' to refer to the ellipsoidal formulation (to be ↵Even Rouault
opposed to the spherical one) Instead of 'elliptical'. Was suggested by @cffk in https://github.com/OSGeo/PROJ/pull/2030#issuecomment-596132341 An elliptical projection is a projection whose global shape fits inside an ellipsoid, like Mollweide. At least according to https://www.merriam-webster.com/dictionary/elliptical%20projection and https://en.wikipedia.org/wiki/Mollweide_projection
2020-03-10utm/ups: make sure to set errno to PJD_ERR_ELLIPSOID_USE_REQUIRED if es==0Even Rouault
ENOMEM was wrongly set after setting PJD_ERR_ELLIPSOID_USE_REQUIRED Note: it is a bit strange to forbid the pure spherical case whereas the maths would allow it. I presume this is due to the typical usage of those methods.
2020-03-05Remove occurences of deprecated PROJ.4 syntaxKristian Evers
+no_defs and +datum has no effect on the behaviour of proj, so can be left out in these examples in the docs. +no_defs in rare occasions would have had an effect in older PROJ versions but not from PROJ 6 and onwards. +datum has ever only been honoured by cs2cs and pj_transform(). Fixes #2017
2020-02-27Doc: Add missing projection property tables (#1992)Chatziargyriou Eleftheria
2020-02-21Doc: advertize lat_0 for proj=nsperEven Rouault
2020-01-25Fix ingestion of +proj=cea with +k_0Even Rouault
Fixes #1881 Digging into the implementation of proj=cea, it appears that k_0 and lat_ts are intended to be exclusive ways of specifying the same concept. EPSG only models the variant using lat_s. So if k_0 is found and lat_ts is absent, compute the equivalent value of lat_ts from k_0. Note: k_0 should normally be in the [0,1] range. In case creative users would use something outside, we raise an exception, even if the cea implementation could potentially deal with any k_0 value. Hopefully this is a (reasonable) limitation that will address nominal use cases.
2019-12-09isea docs: Rewrite intro and reference to reflect actual projectionKristian Evers
Previous version was describing oea by mistake. It is also a projection by Snyder and the isea docs was based on the paper on the oea projection. This commit fixes that.
2019-12-07Add intro and table to isea doc pageKristian Evers
2019-11-25Doc: change 7.0 references to 6.3Even Rouault
2019-10-03ob_tran doc: fix/clarify semantics of o_lat_p/o_lon_pEven Rouault
This is a super confusing topic, but from experiments, and in particular with the example of Fairgrieve projection, o_lat_p and o_lon_p are the coordinates of the North pole of the unrotated geographic CRS expressed in the rotated geographic CRS. This is different from defining a 'new pole', which would be the coordinates of the rotated North pole expressed in the unrotated CRS.
2019-10-01Add rotation support to the HEALPix projection (#1638)Simon Schneegans
2019-09-16Update doc image for bertin1953Kristian Evers
2019-05-22UTM doc: Move +south and +approx parameters to optional sectionKristian Evers
2019-03-14Doc: State that +n is a required for param for urm5Kristian Evers
2019-03-11Doc: fix typo in ob_tranEven Rouault
2019-03-04Further corrections to BibTeXMike Taves
- Use names as published - Change Tobler2017 -> Tobler2018 - Change EPSGGuidanceNumber7Part2 -> IOGP2018
2019-02-28Miscellaneous documentation fixesMike Taves
- Corrections to BibTeX references, normalise format with JabRef - Typos in projinfo - Simplify update CITATION step
2019-02-24Doc: fix plotdefs.json, and aea and lcc descriptions, to take into account ↵Even Rouault
removal of proj_def.dat
2019-02-24Some improvements to the docs for tmerc and omerc (#1281)Thomas Knudsen
2019-02-23Doc: add minimal doumentation for misrsom projectionEven Rouault
2019-02-23Doc: add minimal doumentation for times projectionEven Rouault
2019-02-23Doc: add minimal documentation for sch projectionEven Rouault
2019-02-23Doc: add minimal doumentation for natearth2 projectionEven Rouault
2019-02-23Doc: add minimal doumentation for comill / Compact Miller projectionEven Rouault
2019-02-23Doc: add minimal documentation for patterson projectionEven Rouault
2019-02-11Make tmerc an alias for etmerc. (#1234)Kristian Evers
* Make tmerc an alias for etmerc This switches the algorithm used in tmerc to the Poder/Engsager tmerc algorithm. The original tmerc algorithm of Evenden/Snyder origin can still be accessed by adding the +approx flag when initializing a tmerc projection. The +approx flag can also be used when initializing UTM projections, in which case the Evenden/Snyder algorithm is used as well. If a tmerc projection is instantiated on a spherical earth the Evenden/Snyder algorithm is used as well since the Poder/Engsager algorithm is only defined on the ellipsoid. +proj=etmerc can still be instantiated for backwards compatibility reasons. Co-authored-by: Kristian Evers <kristianevers@gmail.com> Co-authored-by: Even Rouault <even.rouault@spatialys.com>
2018-11-19Doc: fix geos projection explanation about the appropriate value for the ↵Even Rouault
sweep parameter depending on the satellite (fixes #1179)
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