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href="aitoff.html">Aitoff</a></li> +<li class="toctree-l3"><a class="reference internal" href="alsk.html">Modified Stereographic of Alaska</a></li> +<li class="toctree-l3"><a class="reference internal" href="apian.html">Apian Globular I</a></li> +<li class="toctree-l3"><a class="reference internal" href="august.html">August Epicycloidal</a></li> +<li class="toctree-l3"><a class="reference internal" href="bacon.html">Bacon Globular</a></li> +<li class="toctree-l3"><a class="reference internal" href="bertin1953.html">Bertin 1953</a></li> +<li class="toctree-l3"><a class="reference internal" href="bipc.html">Bipolar conic of western hemisphere</a></li> +<li class="toctree-l3"><a class="reference internal" href="boggs.html">Boggs Eumorphic</a></li> +<li class="toctree-l3"><a class="reference internal" href="bonne.html">Bonne (Werner lat_1=90)</a></li> +<li class="toctree-l3"><a class="reference internal" href="calcofi.html">Cal Coop Ocean Fish Invest Lines/Stations</a></li> +<li class="toctree-l3"><a class="reference internal" href="cass.html">Cassini (Cassini-Soldner)</a></li> +<li class="toctree-l3"><a class="reference internal" href="cc.html">Central Cylindrical</a></li> +<li class="toctree-l3"><a class="reference internal" href="ccon.html">Central Conic</a></li> +<li class="toctree-l3"><a class="reference internal" href="cea.html">Equal Area Cylindrical</a></li> +<li class="toctree-l3"><a class="reference internal" href="chamb.html">Chamberlin Trimetric</a></li> +<li class="toctree-l3"><a class="reference internal" href="collg.html">Collignon</a></li> +<li class="toctree-l3"><a class="reference internal" href="col_urban.html">Colombia Urban</a></li> +<li class="toctree-l3"><a class="reference internal" href="comill.html">Compact Miller</a></li> +<li class="toctree-l3"><a class="reference internal" href="crast.html">Craster Parabolic (Putnins P4)</a></li> +<li class="toctree-l3"><a class="reference internal" href="denoy.html">Denoyer Semi-Elliptical</a></li> +<li class="toctree-l3"><a class="reference internal" href="eck1.html">Eckert I</a></li> +<li class="toctree-l3"><a class="reference internal" href="eck2.html">Eckert II</a></li> +<li class="toctree-l3"><a class="reference internal" href="eck3.html">Eckert III</a></li> +<li class="toctree-l3"><a class="reference internal" href="eck4.html">Eckert IV</a></li> +<li class="toctree-l3"><a class="reference internal" href="eck5.html">Eckert V</a></li> +<li class="toctree-l3"><a class="reference internal" href="eck6.html">Eckert VI</a></li> +<li class="toctree-l3"><a class="reference internal" href="eqc.html">Equidistant Cylindrical (Plate Carrée)</a></li> +<li class="toctree-l3"><a class="reference internal" href="eqdc.html">Equidistant Conic</a></li> +<li class="toctree-l3"><a class="reference internal" href="eqearth.html">Equal Earth</a></li> +<li class="toctree-l3"><a class="reference internal" href="euler.html">Euler</a></li> +<li class="toctree-l3"><a class="reference internal" href="fahey.html">Fahey</a></li> +<li class="toctree-l3"><a class="reference internal" href="fouc.html">Foucaut</a></li> +<li class="toctree-l3"><a class="reference internal" href="fouc_s.html">Foucaut Sinusoidal</a></li> +<li class="toctree-l3"><a class="reference internal" href="gall.html">Gall (Gall Stereographic)</a></li> +<li class="toctree-l3"><a class="reference internal" href="geos.html">Geostationary Satellite View</a></li> +<li class="toctree-l3"><a class="reference internal" href="gins8.html">Ginsburg VIII (TsNIIGAiK)</a></li> +<li class="toctree-l3"><a class="reference internal" href="gn_sinu.html">General Sinusoidal Series</a></li> +<li class="toctree-l3"><a class="reference internal" href="gnom.html">Gnomonic</a></li> +<li class="toctree-l3"><a class="reference internal" href="goode.html">Goode Homolosine</a></li> +<li class="toctree-l3"><a class="reference internal" href="gs48.html">Modified Stereographic of 48 U.S.</a></li> +<li class="toctree-l3"><a class="reference internal" href="gs50.html">Modified Stereographic of 50 U.S.</a></li> +<li class="toctree-l3"><a class="reference internal" href="guyou.html">Guyou</a></li> +<li class="toctree-l3"><a class="reference internal" href="hammer.html">Hammer & Eckert-Greifendorff</a></li> +<li class="toctree-l3"><a class="reference internal" href="hatano.html">Hatano Asymmetrical Equal Area</a></li> +<li class="toctree-l3"><a class="reference internal" href="healpix.html">HEALPix</a></li> +<li class="toctree-l3"><a class="reference internal" href="rhealpix.html">rHEALPix</a></li> +<li class="toctree-l3"><a class="reference internal" href="igh.html">Interrupted Goode Homolosine</a></li> +<li class="toctree-l3"><a class="reference internal" href="igh_o.html">Interrupted Goode Homolosine (Oceanic View)</a></li> +<li class="toctree-l3"><a class="reference internal" href="imw_p.html">International Map of the World Polyconic</a></li> +<li class="toctree-l3"><a class="reference internal" href="isea.html">Icosahedral Snyder Equal Area</a></li> +<li class="toctree-l3"><a class="reference internal" href="kav5.html">Kavrayskiy V</a></li> +<li class="toctree-l3"><a class="reference internal" href="kav7.html">Kavrayskiy VII</a></li> +<li class="toctree-l3"><a class="reference internal" href="krovak.html">Krovak</a></li> +<li class="toctree-l3"><a class="reference internal" href="labrd.html">Laborde</a></li> +<li class="toctree-l3"><a class="reference internal" href="laea.html">Lambert Azimuthal Equal Area</a></li> +<li class="toctree-l3"><a class="reference internal" href="lagrng.html">Lagrange</a></li> +<li class="toctree-l3"><a class="reference internal" href="larr.html">Larrivee</a></li> +<li class="toctree-l3"><a class="reference internal" href="lask.html">Laskowski</a></li> +<li class="toctree-l3"><a class="reference internal" href="lcc.html">Lambert Conformal Conic</a></li> +<li class="toctree-l3"><a class="reference internal" href="lcca.html">Lambert Conformal Conic Alternative</a></li> +<li class="toctree-l3"><a class="reference internal" href="leac.html">Lambert Equal Area Conic</a></li> +<li class="toctree-l3"><a class="reference internal" href="lee_os.html">Lee Oblated Stereographic</a></li> +<li class="toctree-l3"><a class="reference internal" href="loxim.html">Loximuthal</a></li> +<li class="toctree-l3"><a class="reference internal" href="lsat.html">Space oblique for LANDSAT</a></li> +<li class="toctree-l3"><a class="reference internal" href="mbt_s.html">McBryde-Thomas Flat-Polar Sine (No. 1)</a></li> +<li class="toctree-l3"><a class="reference internal" href="mbt_fps.html">McBryde-Thomas Flat-Pole Sine (No. 2)</a></li> +<li class="toctree-l3"><a class="reference internal" href="mbtfpp.html">McBride-Thomas Flat-Polar Parabolic</a></li> +<li class="toctree-l3"><a class="reference internal" href="mbtfpq.html">McBryde-Thomas Flat-Polar Quartic</a></li> +<li class="toctree-l3"><a class="reference internal" href="mbtfps.html">McBryde-Thomas Flat-Polar Sinusoidal</a></li> +<li class="toctree-l3"><a class="reference internal" href="merc.html">Mercator</a></li> +<li class="toctree-l3"><a class="reference internal" href="mil_os.html">Miller Oblated Stereographic</a></li> +<li class="toctree-l3"><a class="reference internal" href="mill.html">Miller Cylindrical</a></li> +<li class="toctree-l3"><a class="reference internal" href="misrsom.html">Space oblique for MISR</a></li> +<li class="toctree-l3"><a class="reference internal" href="moll.html">Mollweide</a></li> +<li class="toctree-l3"><a class="reference internal" href="murd1.html">Murdoch I</a></li> +<li class="toctree-l3"><a class="reference internal" href="murd2.html">Murdoch II</a></li> +<li class="toctree-l3"><a class="reference internal" href="murd3.html">Murdoch III</a></li> +<li class="toctree-l3"><a class="reference internal" href="natearth.html">Natural Earth</a></li> +<li class="toctree-l3"><a class="reference internal" href="natearth2.html">Natural Earth II</a></li> +<li class="toctree-l3"><a class="reference internal" href="nell.html">Nell</a></li> +<li class="toctree-l3"><a class="reference internal" href="nell_h.html">Nell-Hammer</a></li> +<li class="toctree-l3"><a class="reference internal" href="nicol.html">Nicolosi Globular</a></li> +<li class="toctree-l3"><a class="reference internal" href="nsper.html">Near-sided perspective</a></li> +<li class="toctree-l3"><a class="reference internal" href="nzmg.html">New Zealand Map Grid</a></li> +<li class="toctree-l3"><a class="reference internal" href="ob_tran.html">General Oblique Transformation</a></li> +<li class="toctree-l3"><a class="reference internal" href="ocea.html">Oblique Cylindrical Equal Area</a></li> +<li class="toctree-l3"><a class="reference internal" href="oea.html">Oblated Equal Area</a></li> +<li class="toctree-l3"><a class="reference internal" href="omerc.html">Oblique Mercator</a></li> +<li class="toctree-l3"><a class="reference internal" href="ortel.html">Ortelius Oval</a></li> +<li class="toctree-l3"><a class="reference internal" href="ortho.html">Orthographic</a></li> +<li class="toctree-l3"><a class="reference internal" href="patterson.html">Patterson</a></li> +<li class="toctree-l3"><a class="reference internal" href="pconic.html">Perspective Conic</a></li> +<li class="toctree-l3"><a class="reference internal" href="peirce_q.html">Peirce Quincuncial</a></li> +<li class="toctree-l3"><a class="reference internal" href="poly.html">Polyconic (American)</a></li> +<li class="toctree-l3"><a class="reference internal" href="putp1.html">Putnins P1</a></li> +<li class="toctree-l3"><a class="reference internal" href="putp2.html">Putnins P2</a></li> +<li class="toctree-l3"><a class="reference internal" href="putp3.html">Putnins P3</a></li> +<li class="toctree-l3"><a class="reference internal" href="putp3p.html">Putnins P3’</a></li> +<li class="toctree-l3"><a class="reference internal" href="putp4p.html">Putnins P4’</a></li> +<li class="toctree-l3"><a class="reference internal" href="putp5.html">Putnins P5</a></li> +<li class="toctree-l3"><a class="reference internal" href="putp5p.html">Putnins P5’</a></li> +<li class="toctree-l3"><a class="reference internal" href="putp6.html">Putnins P6</a></li> +<li class="toctree-l3"><a class="reference internal" href="putp6p.html">Putnins P6’</a></li> +<li class="toctree-l3"><a class="reference internal" href="qua_aut.html">Quartic Authalic</a></li> +<li class="toctree-l3"><a class="reference internal" href="qsc.html">Quadrilateralized Spherical Cube</a></li> +<li class="toctree-l3"><a class="reference internal" href="robin.html">Robinson</a></li> +<li class="toctree-l3"><a class="reference internal" href="rouss.html">Roussilhe Stereographic</a></li> +<li class="toctree-l3"><a class="reference internal" href="rpoly.html">Rectangular Polyconic</a></li> +<li class="toctree-l3 current"><a class="current reference internal" href="#">S2</a><ul> +<li class="toctree-l4"><a class="reference internal" href="#usage">Usage</a></li> +<li class="toctree-l4"><a class="reference internal" href="#parameters">Parameters</a></li> +<li class="toctree-l4"><a class="reference internal" href="#further-reading">Further reading</a></li> +</ul> +</li> +<li class="toctree-l3"><a class="reference internal" href="sch.html">Spherical Cross-track Height</a></li> +<li class="toctree-l3"><a class="reference internal" href="sinu.html">Sinusoidal (Sanson-Flamsteed)</a></li> +<li class="toctree-l3"><a class="reference internal" href="somerc.html">Swiss Oblique Mercator</a></li> +<li class="toctree-l3"><a class="reference internal" href="stere.html">Stereographic</a></li> +<li class="toctree-l3"><a class="reference internal" href="sterea.html">Oblique Stereographic Alternative</a></li> +<li class="toctree-l3"><a class="reference internal" href="gstmerc.html">Gauss-Schreiber Transverse Mercator (aka Gauss-Laborde Reunion)</a></li> +<li class="toctree-l3"><a class="reference internal" href="tcc.html">Transverse Central Cylindrical</a></li> +<li class="toctree-l3"><a class="reference internal" href="tcea.html">Transverse Cylindrical Equal Area</a></li> +<li class="toctree-l3"><a class="reference internal" href="times.html">Times</a></li> +<li class="toctree-l3"><a class="reference internal" href="tissot.html">Tissot</a></li> +<li class="toctree-l3"><a class="reference internal" href="tmerc.html">Transverse Mercator</a></li> +<li class="toctree-l3"><a class="reference internal" href="tobmerc.html">Tobler-Mercator</a></li> +<li class="toctree-l3"><a class="reference internal" href="tpeqd.html">Two Point Equidistant</a></li> +<li class="toctree-l3"><a class="reference internal" href="tpers.html">Tilted perspective</a></li> +<li class="toctree-l3"><a class="reference internal" href="ups.html">Universal Polar Stereographic</a></li> +<li class="toctree-l3"><a class="reference internal" href="urm5.html">Urmaev V</a></li> +<li class="toctree-l3"><a class="reference internal" href="urmfps.html">Urmaev Flat-Polar Sinusoidal</a></li> +<li class="toctree-l3"><a class="reference internal" href="utm.html">Universal Transverse Mercator (UTM)</a></li> +<li class="toctree-l3"><a class="reference internal" href="vandg.html">van der Grinten (I)</a></li> +<li class="toctree-l3"><a class="reference internal" href="vandg2.html">van der Grinten II</a></li> +<li class="toctree-l3"><a class="reference internal" href="vandg3.html">van der Grinten III</a></li> +<li class="toctree-l3"><a class="reference internal" href="vandg4.html">van der Grinten IV</a></li> +<li class="toctree-l3"><a class="reference internal" href="vitk1.html">Vitkovsky I</a></li> +<li class="toctree-l3"><a class="reference internal" href="wag1.html">Wagner I (Kavrayskiy VI)</a></li> +<li class="toctree-l3"><a class="reference internal" href="wag2.html">Wagner II</a></li> +<li class="toctree-l3"><a class="reference internal" href="wag3.html">Wagner III</a></li> +<li class="toctree-l3"><a class="reference internal" href="wag4.html">Wagner IV</a></li> +<li class="toctree-l3"><a class="reference internal" href="wag5.html">Wagner V</a></li> +<li class="toctree-l3"><a class="reference internal" href="wag6.html">Wagner VI</a></li> +<li class="toctree-l3"><a class="reference internal" href="wag7.html">Wagner VII</a></li> +<li class="toctree-l3"><a class="reference internal" href="webmerc.html">Web Mercator / Pseudo Mercator</a></li> +<li class="toctree-l3"><a class="reference internal" href="weren.html">Werenskiold I</a></li> +<li class="toctree-l3"><a class="reference internal" href="wink1.html">Winkel I</a></li> +<li class="toctree-l3"><a class="reference internal" href="wink2.html">Winkel II</a></li> +<li class="toctree-l3"><a class="reference internal" href="wintri.html">Winkel Tripel</a></li> +</ul> +</li> +<li class="toctree-l2"><a class="reference internal" href="../conversions/index.html">Conversions</a></li> +<li class="toctree-l2"><a class="reference internal" href="../transformations/index.html">Transformations</a></li> +<li class="toctree-l2"><a class="reference internal" href="../pipeline.html">The pipeline operator</a></li> +<li class="toctree-l2"><a class="reference internal" href="../operations_computation.html">Computation of coordinate operations between two CRS</a></li> +</ul> +</li> +<li class="toctree-l1"><a class="reference internal" href="../../resource_files.html">Resource files</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../geodesic.html">Geodesic calculations</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../development/index.html">Development</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../specifications/index.html">Specifications</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../community/index.html">Community</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../faq.html">FAQ</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../glossary.html">Glossary</a></li> +<li class="toctree-l1"><a class="reference internal" href="../../zreferences.html">References</a></li> +</ul> + + </div> + </div> + </nav> + + <section data-toggle="wy-nav-shift" class="wy-nav-content-wrap"><nav class="wy-nav-top" aria-label="Mobile navigation menu" style="background: #353130" > + <i data-toggle="wy-nav-top" class="fa fa-bars"></i> + <a href="../../index.html">PROJ</a> + </nav> + + <div class="wy-nav-content"> + <div class="rst-content"> + <div role="navigation" aria-label="Page navigation"> + <ul class="wy-breadcrumbs"> + <li><a href="../../index.html" class="icon icon-home"></a> »</li> + <li><a href="../index.html">Coordinate operations</a> »</li> + <li><a href="index.html">Projections</a> »</li> + <li>S2</li> + <li class="wy-breadcrumbs-aside"> + <a href="https://github.com/OSGeo/PROJ/edit/8.2/docs/source/operations/projections/s2.rst" class="fa fa-github"> Edit on GitHub</a> + </li> + </ul><div class="rst-breadcrumbs-buttons" role="navigation" aria-label="Sequential page navigation"> + <a href="rpoly.html" class="btn btn-neutral float-left" title="Rectangular Polyconic" accesskey="p"><span class="fa fa-arrow-circle-left" aria-hidden="true"></span> Previous</a> + <a href="sch.html" class="btn btn-neutral float-right" title="Spherical Cross-track Height" accesskey="n">Next <span class="fa fa-arrow-circle-right" aria-hidden="true"></span></a> + </div> + <hr/> +</div> + <div role="main" class="document" itemscope="itemscope" itemtype="http://schema.org/Article"> + <div itemprop="articleBody"> + + <section id="s2"> +<span id="id1"></span><h1>S2<a class="headerlink" href="#s2" title="Permalink to this headline">¶</a></h1> +<table class="docutils align-default"> +<colgroup> +<col style="width: 27%" /> +<col style="width: 73%" /> +</colgroup> +<tbody> +<tr class="row-odd"><td><p><strong>Classification</strong></p></td> +<td><p>Miscellaneous</p></td> +</tr> +<tr class="row-even"><td><p><strong>Available forms</strong></p></td> +<td><p>Forward and inverse, ellipsoidal</p></td> +</tr> +<tr class="row-odd"><td><p><strong>Defined area</strong></p></td> +<td><p>Global</p></td> +</tr> +<tr class="row-even"><td><p><strong>Alias</strong></p></td> +<td><p>s2</p></td> +</tr> +<tr class="row-odd"><td><p><strong>Domain</strong></p></td> +<td><p>2D</p></td> +</tr> +<tr class="row-even"><td><p><strong>Input type</strong></p></td> +<td><p>Geodetic coordinates</p></td> +</tr> +<tr class="row-odd"><td><p><strong>Output type</strong></p></td> +<td><p>Projected coordinates</p></td> +</tr> +</tbody> +</table> +<div class="versionadded"> +<p><span class="versionmodified added">New in version 8.2.</span></p> +</div> +<p>The S2 projection, like the Quadrilateralized Spherical Cube (QSC) projection, projects +a sphere surface onto the six sides of a cube:</p> +<a class="reference internal image-reference" href="../../_images/qsc_concept.jpg"><img alt="Quadrilateralized Spherical Cube" class="align-center" src="../../_images/qsc_concept.jpg" style="width: 500px;" /></a> +<p>S2 was created by Google to represent geographic data on the whole earth. The documentation can be found +at <a class="reference external" href="https://s2geometry.io/">S2 Geometry</a> It works by first +projecting a point on the sphere to a face of the cube. These are called u,v-coordinates, and they are in [-1,1] x [-1,1]. +This step is followed by a non-linear transformation to normalize the area of rectangles on the sphere. There are three +different choices available for this transformation, meaning that S2 is a family of projections. The final output is in +s,t-coordinates, which are in [0,1] x [0,1]. +See the comments in <a class="reference external" href="https://github.com/google/s2geometry/blob/0c4c460bdfe696da303641771f9def900b3e440f/src/s2/s2coords.h#L226">S2 Code</a> +for an explanation of the tradeoff between speed and area-preservation. Note that the projection is azimuthal when “none” or +“linear” is selected for the area-normalization, but it is not azimuthal when “quadratic” or “tangent” is chosen. See +S2’s <a class="reference external" href="https://s2geometry.io/resources/earthcube">Earthcube page</a> +to visualize the unfolded cube and the orientation of each face.</p> +<p>In this implementation, the cube side is selected by choosing one of the following six projection centers:</p> +<table class="docutils align-default"> +<colgroup> +<col style="width: 56%" /> +<col style="width: 44%" /> +</colgroup> +<tbody> +<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">+lat_0=0</span> <span class="pre">+lon_0=0</span></code></p></td> +<td><p>front cube side</p></td> +</tr> +<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">+lat_0=0</span> <span class="pre">+lon_0=90</span></code></p></td> +<td><p>right cube side</p></td> +</tr> +<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">+lat_0=0</span> <span class="pre">+lon_0=180</span></code></p></td> +<td><p>back cube side</p></td> +</tr> +<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">+lat_0=0</span> <span class="pre">+lon_0=-90</span></code></p></td> +<td><p>left cube side</p></td> +</tr> +<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">+lat_0=90</span></code></p></td> +<td><p>top cube side</p></td> +</tr> +<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">+lat_0=-90</span></code></p></td> +<td><p>bottom cube side</p></td> +</tr> +</tbody> +</table> +<p>The specific transformation can be chosen with the UVtoST parameter:</p> +<table class="docutils align-default"> +<colgroup> +<col style="width: 46%" /> +<col style="width: 54%" /> +</colgroup> +<tbody> +<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">+UVtoST=linear</span></code></p></td> +<td><p>fastest, no normalization</p></td> +</tr> +<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">+UVtoST=quadratic</span></code></p></td> +<td><p>fast, good normalization</p></td> +</tr> +<tr class="row-odd"><td><p><code class="docutils literal notranslate"><span class="pre">+UVtoST=tangent</span></code></p></td> +<td><p>slowest, best normalization</p></td> +</tr> +<tr class="row-even"><td><p><code class="docutils literal notranslate"><span class="pre">+UVtoST=none</span></code></p></td> +<td><p>returns u,v-coordinates</p></td> +</tr> +</tbody> +</table> +<p>Furthermore, this implementation allows the projection to be applied to ellipsoids. +A preceding shift to a sphere is performed automatically; see <span id="id2">[<a class="reference internal" href="../../zreferences.html#id25" title="Lambers, M. and Kolb, A. Ellipsoidal cube maps for accurate rendering of planetary-scale terrain data. In Bregler, C., Sander, P., and Wimmer, M., editors, Pacific Graphics Short Papers. The Eurographics Association, 2012. doi:10.2312/PE/PG/PG2012short/005-010.">LambersKolb2012</a>]</span> for details. +The output of the projection is in s,t-coordinates ([0,1] x [0,1]), so only the +eccentricity of the ellipse is taken into account: the absolute value of the axes does +not affect the output.</p> +<section id="usage"> +<h2>Usage<a class="headerlink" href="#usage" title="Permalink to this headline">¶</a></h2> +<p>The following example uses S2 on the right face:</p> +<div class="highlight-none notranslate"><div class="highlight"><pre><span></span>echo 90 0 | ../bin/proj +proj=s2 +lat_0=0 +lon_0=90 +ellps=WGS84 +UVtoST=linear + +0.5 0.5 +</pre></div> +</div> +<p>Explanation:</p> +<ul class="simple"> +<li><p>S2 projection is selected with <code class="docutils literal notranslate"><span class="pre">+proj=s2</span></code>.</p></li> +<li><p>The WGS84 ellipsoid is specified with <code class="docutils literal notranslate"><span class="pre">+ellps=WGS84</span></code>.</p></li> +<li><p>The cube side is selected with <code class="docutils literal notranslate"><span class="pre">+lat_0=...</span> <span class="pre">+lon_0=...</span></code>.</p></li> +<li><p>The normalization transformation is selected with <code class="docutils literal notranslate"><span class="pre">+UVtoST=...</span></code>.</p></li> +</ul> +</section> +<section id="parameters"> +<h2>Parameters<a class="headerlink" href="#parameters" title="Permalink to this headline">¶</a></h2> +<div class="admonition note"> +<p class="admonition-title">Note</p> +<p>All parameters for the projection are optional.</p> +</div> +<dl class="std option"> +<dt class="sig sig-object std" id="cmdoption-arg-lon_0"> +<span id="cmdoption-arg-lon-0"></span><span class="sig-name descname"><span class="pre">+lon_0</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-lon_0" title="Permalink to this definition">¶</a></dt> +<dd><p>Longitude of projection center.</p> +<p><em>Defaults to 0.0.</em></p> +</dd></dl> + +<dl class="std option"> +<dt class="sig sig-object std" id="cmdoption-arg-lat_0"> +<span id="cmdoption-arg-lat-0"></span><span class="sig-name descname"><span class="pre">+lat_0</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-lat_0" title="Permalink to this definition">¶</a></dt> +<dd><p>Latitude of projection center.</p> +<p><em>Defaults to 0.0.</em></p> +</dd></dl> + +<dl class="std option"> +<dt class="sig sig-object std" id="cmdoption-arg-ellps"> +<span class="sig-name descname"><span class="pre">+ellps</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-ellps" title="Permalink to this definition">¶</a></dt> +<dd><p>The name of a built-in ellipsoid definition.</p> +<p>See <a class="reference internal" href="../../usage/ellipsoids.html#ellipsoids"><span class="std std-ref">Ellipsoids</span></a> for more information, or execute +<a class="reference internal" href="../../apps/proj.html#cmdoption-proj-le"><code class="xref std std-option docutils literal notranslate"><span class="pre">proj</span> <span class="pre">-le</span></code></a> for a list of built-in ellipsoid names.</p> +<p><em>Defaults to “GRS80”.</em></p> +</dd></dl> + +<dl class="std option"> +<dt class="sig sig-object std" id="cmdoption-arg-UVtoST"> +<span id="cmdoption-arg-uvtost"></span><span class="sig-name descname"><span class="pre">+UVtoST</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-UVtoST" title="Permalink to this definition">¶</a></dt> +<dd><p>The area-normalization transformation. Choose from {linear, quadratic, tangent, none}</p> +<p><em>Defaults to “quadratic”.</em></p> +</dd></dl> + +<dl class="std option"> +<dt class="sig sig-object std" id="cmdoption-arg-x_0"> +<span id="cmdoption-arg-x-0"></span><span class="sig-name descname"><span class="pre">+x_0</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-x_0" title="Permalink to this definition">¶</a></dt> +<dd><p>False easting.</p> +<p><em>Defaults to 0.0.</em></p> +</dd></dl> + +<dl class="std option"> +<dt class="sig sig-object std" id="cmdoption-arg-y_0"> +<span id="cmdoption-arg-y-0"></span><span class="sig-name descname"><span class="pre">+y_0</span></span><span class="sig-prename descclassname"><span class="pre">=<value></span></span><a class="headerlink" href="#cmdoption-arg-y_0" title="Permalink to this definition">¶</a></dt> +<dd><p>False northing.</p> +<p><em>Defaults to 0.0.</em></p> +</dd></dl> + +</section> +<section id="further-reading"> +<h2>Further reading<a class="headerlink" href="#further-reading" title="Permalink to this headline">¶</a></h2> +<ol class="arabic simple"> +<li><p><a class="reference external" href="https://s2geometry.io/">S2’s Website</a></p></li> +</ol> +</section> +</section> + + + </div> + </div> + <footer><div class="rst-footer-buttons" role="navigation" aria-label="Footer"> + <a href="rpoly.html" class="btn btn-neutral float-left" title="Rectangular Polyconic" accesskey="p" rel="prev"><span class="fa fa-arrow-circle-left" aria-hidden="true"></span> Previous</a> + <a href="sch.html" class="btn btn-neutral float-right" title="Spherical Cross-track Height" accesskey="n" rel="next">Next <span class="fa fa-arrow-circle-right" aria-hidden="true"></span></a> + </div> + + <hr/> + + <div role="contentinfo"> + <p>© Copyright 1983-2022. + <span class="lastupdated">Last updated on 22 Mar 2022. + </span></p> + </div> + + Built with <a href="https://www.sphinx-doc.org/">Sphinx</a> using a + <a href="https://github.com/readthedocs/sphinx_rtd_theme">theme</a> + provided by <a href="https://readthedocs.org">Read the Docs</a>. + + +</footer> + </div> + </div> + </section> + </div> + <script> + jQuery(function () { + SphinxRtdTheme.Navigation.enable(true); + }); + </script> + +</body> +</html>
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