Add QgsCoordinateReferenceSystem::celestialBodyName

Returns the associated celestial body name (proj 8.1+ only)
qgis · May 10, 2021 · 95ed5ec · 95ed5ec
1 parent 27085cf
commit 95ed5ec
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diff --git a/python/core/auto_generated/proj/qgscelestialbody.sip.in b/python/core/auto_generated/proj/qgscelestialbody.sip.in
@@ -0,0 +1,71 @@
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/core/proj/qgscelestialbody.h                                     *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
+
+
+
+class QgsCelestialBody
+{
+%Docstring(signature="appended")
+Contains information about a celestial body.
+
+.. note::
+
+   Only used in builds based on on PROJ 8.1 or later
+
+.. versionadded:: 3.20
+%End
+
+%TypeHeaderCode
+#include "qgscelestialbody.h"
+%End
+  public:
+
+    bool isValid() const;
+%Docstring
+Returns ``True`` if the body is a valid object, or ``False`` if it is a null/invalid
+object.
+%End
+
+    QString name() const;
+%Docstring
+Name of celestial body.
+%End
+
+    QString authority() const;
+%Docstring
+Authority name, e.g. EPSG.
+%End
+
+    SIP_PYOBJECT __repr__();
+%MethodCode
+    QString str;
+    if ( !sipCpp->isValid() )
+    {
+      str = QStringLiteral( "<QgsCelestialBody: invalid>" );
+    }
+    else
+    {
+      QString id;
+      if ( !sipCpp->authority().isEmpty() )
+        id = QStringLiteral( "%1 (%2)" ).arg( sipCpp->name(), sipCpp->authority() );
+      else
+        id = sipCpp->name();
+      str = QStringLiteral( "<QgsCelestialBody: %1>" ).arg( id );
+    }
+    sipRes = PyUnicode_FromString( str.toUtf8().constData() );
+%End
+
+};
+
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/core/proj/qgscelestialbody.h                                     *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
diff --git a/python/core/auto_generated/proj/qgscoordinatereferencesystem.sip.in b/python/core/auto_generated/proj/qgscoordinatereferencesystem.sip.in
@@ -817,6 +817,20 @@ be returned.
 :raises :: py:class:`QgsNotSupportedException` on QGIS builds based on PROJ 7 or earlier.
 
 
+.. versionadded:: 3.20
+%End
+
+    QString celestialBodyName() const throw( QgsNotSupportedException );
+%Docstring
+Attempts to retrieve the name of the celestial body associated with the CRS (e.g. "Earth").
+
+.. warning::
+
+   This method requires PROJ 8.1 or later
+
+:raises :: py:class:`QgsNotSupportedException` on QGIS builds based on PROJ 8.0 or earlier.
+
+
 .. versionadded:: 3.20
 %End
 

diff --git a/src/core/proj/qgscelestialbody.h b/src/core/proj/qgscelestialbody.h
@@ -0,0 +1,81 @@
+/***************************************************************************
+               qgscelestialbody.h
+               ------------------------
+    begin                : May 2021
+    copyright            : (C) 2021 Nyall Dawson
+    email                : nyall dot dawson at gmail dot com
+ ***************************************************************************/
+
+/***************************************************************************
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ ***************************************************************************/
+#ifndef QGSCELESTIALBODY_H
+#define QGSCELESTIALBODY_H
+
+#include "qgis_core.h"
+#include "qgis_sip.h"
+#include <QString>
+
+/**
+ * \ingroup core
+ * \brief Contains information about a celestial body.
+ *
+ * \note Only used in builds based on on PROJ 8.1 or later
+ * \since QGIS 3.20
+ */
+class CORE_EXPORT QgsCelestialBody
+{
+  public:
+
+    /**
+     * Returns TRUE if the body is a valid object, or FALSE if it is a null/invalid
+     * object.
+     */
+    bool isValid() const { return mValid; }
+
+    /**
+     * Name of celestial body.
+     */
+    QString name() const { return mName; }
+
+    /**
+     * Authority name, e.g. EPSG.
+     */
+    QString authority() const { return mAuthority; }
+
+#ifdef SIP_RUN
+    SIP_PYOBJECT __repr__();
+    % MethodCode
+    QString str;
+    if ( !sipCpp->isValid() )
+    {
+      str = QStringLiteral( "<QgsCelestialBody: invalid>" );
+    }
+    else
+    {
+      QString id;
+      if ( !sipCpp->authority().isEmpty() )
+        id = QStringLiteral( "%1 (%2)" ).arg( sipCpp->name(), sipCpp->authority() );
+      else
+        id = sipCpp->name();
+      str = QStringLiteral( "<QgsCelestialBody: %1>" ).arg( id );
+    }
+    sipRes = PyUnicode_FromString( str.toUtf8().constData() );
+    % End
+#endif
+
+  private:
+
+    bool mValid = false;
+    QString mName;
+    QString mAuthority;
+
+    friend class QgsCoordinateReferenceSystemRegistry;
+};
+
+#endif // QGSCELESTIALBODY_H
diff --git a/src/core/proj/qgscoordinatereferencesystem.cpp b/src/core/proj/qgscoordinatereferencesystem.cpp
@@ -1210,6 +1210,21 @@ bool QgsCoordinateReferenceSystem::isDynamic() const
   return QgsProjUtils::isDynamic( pj );
 }
 
+QString QgsCoordinateReferenceSystem::celestialBodyName() const
+{
+  const PJ *pj = projObject();
+  if ( !pj )
+    return QString();
+
+#if PROJ_VERSION_MAJOR>8 || (PROJ_VERSION_MAJOR==8 && PROJ_VERSION_MINOR>=1)
+  PJ_CONTEXT *context = QgsProjContext::get();
+
+  return QString( proj_get_celestial_body_name( context, pj ) );
+#else
+  throw QgsNotSupportedException( QStringLiteral( "Retrieving celestial body requires a QGIS build based on PROJ 8.1 or later" ) );
+#endif
+}
+
 void QgsCoordinateReferenceSystem::setCoordinateEpoch( double epoch )
 {
   if ( d->mCoordinateEpoch == epoch )

diff --git a/src/core/proj/qgscoordinatereferencesystem.h b/src/core/proj/qgscoordinatereferencesystem.h
@@ -756,6 +756,17 @@ class CORE_EXPORT QgsCoordinateReferenceSystem
      */
     QgsDatumEnsemble datumEnsemble() const SIP_THROW( QgsNotSupportedException );
 
+    /**
+     * Attempts to retrieve the name of the celestial body associated with the CRS (e.g. "Earth").
+     *
+     * \warning This method requires PROJ 8.1 or later
+     *
+     * \throws QgsNotSupportedException on QGIS builds based on PROJ 8.0 or earlier.
+     *
+     * \since QGIS 3.20
+     */
+    QString celestialBodyName() const SIP_THROW( QgsNotSupportedException );
+
     /**
      * Sets the coordinate \a epoch, as a decimal year.
      *

diff --git a/src/gui/qgsprojectionselectiontreewidget.cpp b/src/gui/qgsprojectionselectiontreewidget.cpp
@@ -957,6 +957,19 @@ void QgsProjectionSelectionTreeWidget::updateBoundsPreview()
   }
   properties << ( currentCrs.isDynamic() ? tr( "Dynamic (relies on a datum which is not plate-fixed)" ) : tr( "Static (relies on a datum which is plate-fixed)" ) );
 
+  try
+  {
+    const QString celestialBody = currentCrs.celestialBodyName();
+    if ( !celestialBody.isEmpty() )
+    {
+      properties << tr( "Celestial body: %1" ).arg( celestialBody );
+    }
+  }
+  catch ( QgsNotSupportedException & )
+  {
+
+  }
+
   try
   {
     const QgsDatumEnsemble ensemble = currentCrs.datumEnsemble();

diff --git a/tests/src/core/testqgscoordinatereferencesystem.cpp b/tests/src/core/testqgscoordinatereferencesystem.cpp
@@ -79,6 +79,7 @@ class TestQgsCoordinateReferenceSystem: public QObject
     void isGeographic();
     void mapUnits();
     void isDynamic();
+    void celestialBody();
     void setValidationHint();
     void hasAxisInverted();
     void createFromProjInvalid();
@@ -1333,6 +1334,20 @@ void TestQgsCoordinateReferenceSystem::isDynamic()
 #endif
 }
 
+void TestQgsCoordinateReferenceSystem::celestialBody()
+{
+#if (PROJ_VERSION_MAJOR>8 || (PROJ_VERSION_MAJOR==8 && PROJ_VERSION_MINOR >= 1 ) )
+  QgsCoordinateReferenceSystem crs;
+  QCOMPARE( crs.celestialBodyName(), QString() );
+
+  crs = QgsCoordinateReferenceSystem( QStringLiteral( "EPSG:4326" ) );
+  QCOMPARE( crs.celestialBodyName(), QStringLiteral( "Earth" ) );
+
+  crs = QgsCoordinateReferenceSystem( QStringLiteral( "ESRI:104903" ) );
+  QCOMPARE( crs.celestialBodyName(), QStringLiteral( "Moon" ) );
+#endif
+}
+
 void TestQgsCoordinateReferenceSystem::setValidationHint()
 {
   QgsCoordinateReferenceSystem myCrs;