[api] Add a proper registry for 3D symbol types

python/core/auto_generated/3d/qgs3dsymbolregistry.sip.in

@@ -0,0 +1,117 @@
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/core/./3d/qgs3dsymbolregistry.h                                  *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/
+
+
+
+
+
+class Qgs3DSymbolAbstractMetadata
+{
+%Docstring
+Stores metadata about one 3D symbol class.
+
+.. note::
+
+   It's necessary to implement :py:func:`~createSymbol` function.
+   In C++ you can use Qgs3DSymbolMetadata convenience class.
+
+.. versionadded:: 3.16
+%End
+
+%TypeHeaderCode
+#include "qgs3dsymbolregistry.h"
+%End
+  public:
+
+    Qgs3DSymbolAbstractMetadata( const QString &type, const QString &visibleName );
+%Docstring
+Constructor for Qgs3DSymbolAbstractMetadata, with the specified ``type`` and ``visibleName``.
+%End
+
+    virtual ~Qgs3DSymbolAbstractMetadata();
+
+    QString type() const;
+%Docstring
+Returns the unique symbol type string.
+%End
+
+    QString visibleName() const;
+%Docstring
+Returns the symbol's visible (translated) name.
+%End
+
+    virtual QgsAbstract3DSymbol *create() = 0 /Factory/;
+%Docstring
+Creates a new instance of this symbol type.
+
+Caller takes ownership of the returned symbol.
+%End
+
+
+};
+
+
+
+
+
+class Qgs3DSymbolRegistry
+{
+%Docstring
+Registry of available 3D symbol classes.
+
+Qgs3DSymbolRegistry is not usually directly created, but rather accessed through
+:py:func:`QgsApplication.symbol3DRegistry()`.
+
+.. versionadded:: 3.16
+%End
+
+%TypeHeaderCode
+#include "qgs3dsymbolregistry.h"
+%End
+  public:
+
+    Qgs3DSymbolRegistry();
+    ~Qgs3DSymbolRegistry();
+
+
+    Qgs3DSymbolAbstractMetadata *symbolMetadata( const QString &type ) const;
+%Docstring
+Returns metadata for specified symbol ``type``. Returns ``None`` if not found
+%End
+
+    QStringList symbolTypes() const;
+%Docstring
+Returns a list of all available symbol types.
+%End
+
+    bool addSymbolType( Qgs3DSymbolAbstractMetadata *metadata /Transfer/ );
+%Docstring
+Registers a new symbol type. Takes ownership of the ``metadata`` instance.
+%End
+
+    QgsAbstract3DSymbol *createSymbol( const QString &type ) const /Factory/;
+%Docstring
+Creates a new instance of a symbol of the specified ``type``.
+
+The caller takes ownership of the returned symbol.
+
+Returns ``None`` if the specified type is not found in the registry.
+%End
+
+  private:
+    Qgs3DSymbolRegistry( const Qgs3DSymbolRegistry &rh );
+};
+
+
+/************************************************************************
+ * This file has been generated automatically from                      *
+ *                                                                      *
+ * src/core/./3d/qgs3dsymbolregistry.h                                  *
+ *                                                                      *
+ * Do not edit manually ! Edit header and run scripts/sipify.pl again   *
+ ************************************************************************/

python/core/auto_generated/qgsapplication.sip.in

@@ -850,6 +850,13 @@ Gets the registry of available field formatters.
 Returns registry of available 3D renderers.
 
 .. versionadded:: 3.0
+%End
+
+    static Qgs3DSymbolRegistry *symbol3DRegistry() /KeepReference/;
+%Docstring
+Returns registry of available 3D symbols.
+
+.. versionadded:: 3.16
 %End
 
     static QgsScaleBarRendererRegistry *scaleBarRendererRegistry() /KeepReference/;

python/core/core_auto.sip

@@ -251,6 +251,7 @@
 %Include auto_generated/qgsxmlutils.sip
 %Include auto_generated/qgsziputils.sip
 %Include auto_generated/./3d/qgs3drendererregistry.sip
+%Include auto_generated/./3d/qgs3dsymbolregistry.sip
 %Include auto_generated/./3d/qgsabstract3dsymbol.sip
 %Include auto_generated/./3d/qgsabstract3drenderer.sip
 %Include auto_generated/annotations/qgsannotation.sip

src/core/3d/qgs3dsymbolregistry.cpp

@@ -0,0 +1,52 @@
+/***************************************************************************
+  qgs3dsymbolregistry.cpp
+  --------------------------------------
+  Date                 : July 2020
+  Copyright            : (C) 2020 by 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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "qgs3dsymbolregistry.h"
+
+Qgs3DSymbolRegistry::Qgs3DSymbolRegistry()
+{
+}
+
+Qgs3DSymbolRegistry::~Qgs3DSymbolRegistry()
+{
+  qDeleteAll( mMetadata );
+}
+
+bool Qgs3DSymbolRegistry::addSymbolType( Qgs3DSymbolAbstractMetadata *metadata )
+{
+  if ( !metadata || mMetadata.contains( metadata->type() ) )
+    return false;
+
+  mMetadata[metadata->type()] = metadata;
+  return true;
+}
+
+QgsAbstract3DSymbol *Qgs3DSymbolRegistry::createSymbol( const QString &type ) const
+{
+  if ( !mMetadata.contains( type ) )
+    return nullptr;
+
+  return mMetadata[type]->create();
+}
+
+Qgs3DSymbolAbstractMetadata *Qgs3DSymbolRegistry::symbolMetadata( const QString &type ) const
+{
+  return mMetadata.value( type );
+}
+
+QStringList Qgs3DSymbolRegistry::symbolTypes() const
+{
+  return mMetadata.keys();
+}

src/core/3d/qgs3dsymbolregistry.h

@@ -0,0 +1,201 @@
+/***************************************************************************
+  qgs3dsymbolregistry.h
+  --------------------------------------
+  Date                 : July 2020
+  Copyright            : (C) 2020 by 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 QGS3DSYMBOLREGISTRY_H
+#define QGS3DSYMBOLREGISTRY_H
+
+#include "qgis_core.h"
+#include "qgis_sip.h"
+
+#include <QDomElement>
+#include <QMap>
+
+class QgsAbstract3DSymbol;
+class QgsReadWriteContext;
+class Qgs3DSymbolWidget;
+class QgsVectorLayer;
+
+/**
+ * \ingroup core
+ * Stores metadata about one 3D symbol class.
+ *
+ * \note It's necessary to implement createSymbol() function.
+ * In C++ you can use Qgs3DSymbolMetadata convenience class.
+ *
+ * \since QGIS 3.16
+ */
+class CORE_EXPORT Qgs3DSymbolAbstractMetadata
+{
+  public:
+
+    /**
+     * Constructor for Qgs3DSymbolAbstractMetadata, with the specified \a type and \a visibleName.
+     */
+    Qgs3DSymbolAbstractMetadata( const QString &type, const QString &visibleName )
+      : mType( type )
+      , mVisibleName( visibleName )
+    {}
+
+    virtual ~Qgs3DSymbolAbstractMetadata() = default;
+
+    /**
+     * Returns the unique symbol type string.
+     */
+    QString type() const { return mType; }
+
+    /**
+     * Returns the symbol's visible (translated) name.
+     */
+    QString visibleName() const { return mVisibleName; }
+
+    /**
+     * Creates a new instance of this symbol type.
+     *
+     * Caller takes ownership of the returned symbol.
+     */
+    virtual QgsAbstract3DSymbol *create() = 0 SIP_FACTORY;
+
+#ifndef SIP_RUN
+
+    /**
+     * Create a widget for configuring a symbol of this type.
+     *
+     * Can return NULLPTR if there's no GUI.
+     *
+     * \note Not available in Python bindings
+     */
+    virtual Qgs3DSymbolWidget *createSymbolWidget( QgsVectorLayer * ) SIP_FACTORY { return nullptr; }
+#endif
+
+  private:
+    QString mType;
+    QString mVisibleName;
+};
+
+//! 3D symbol creation function
+typedef QgsAbstract3DSymbol *( *Qgs3DSymbolCreateFunc )() SIP_SKIP;
+
+//! 3D symbol widget creation function
+typedef Qgs3DSymbolWidget *( *Qgs3DSymbolWidgetFunc )( QgsVectorLayer * ) SIP_SKIP;
+
+#ifndef SIP_RUN
+
+/**
+ * \ingroup core
+ * Convenience metadata class that uses static functions to create a 3D symbol and its widget.
+ *
+ * \note Not available in Python bindings.
+ *
+ * \since QGIS 3.16
+ */
+class CORE_EXPORT Qgs3DSymbolMetadata : public Qgs3DSymbolAbstractMetadata
+{
+  public:
+
+    /**
+     * Constructor for Qgs3DSymbolMetadata, with the specified \a type and \a visibleName.
+     *
+     * The \a pfCreate and \a pfWidget arguments are used to specify
+     * static functions for creating the symbol type and configuration widget.
+     */
+    Qgs3DSymbolMetadata( const QString &type, const QString &visibleName,
+                         Qgs3DSymbolCreateFunc pfCreate,
+                         Qgs3DSymbolWidgetFunc pfWidget = nullptr ) SIP_SKIP
+  : Qgs3DSymbolAbstractMetadata( type, visibleName )
+    , mCreateFunc( pfCreate )
+    , mWidgetFunc( pfWidget )
+    {}
+
+    /**
+     * Returns the symbol type's creation function.
+     */
+    Qgs3DSymbolCreateFunc createFunction() const { return mCreateFunc; }
+
+    /**
+     * Returns the symbol type's widget creation function.
+     *
+     * \see setWidgetFunction()
+     */
+    Qgs3DSymbolWidgetFunc widgetFunction() const { return mWidgetFunc; }
+
+    /**
+     * Sets the symbol type's widget creation \a function.
+     *
+     * \see widgetFunction()
+     */
+    void setWidgetFunction( Qgs3DSymbolWidgetFunc function ) { mWidgetFunc = function; }
+
+    QgsAbstract3DSymbol *create() override SIP_FACTORY { return mCreateFunc ? mCreateFunc() : nullptr; }
+    Qgs3DSymbolWidget *createSymbolWidget( QgsVectorLayer *vl ) override SIP_FACTORY { return mWidgetFunc ? mWidgetFunc( vl ) : nullptr; }
+
+  private:
+    Qgs3DSymbolCreateFunc mCreateFunc;
+    Qgs3DSymbolWidgetFunc mWidgetFunc;
+
+};
+#endif
+
+
+/**
+ * \ingroup core
+ * Registry of available 3D symbol classes.
+ *
+ * Qgs3DSymbolRegistry is not usually directly created, but rather accessed through
+ * QgsApplication::symbol3DRegistry().
+ *
+ * \since QGIS 3.16
+ */
+class CORE_EXPORT Qgs3DSymbolRegistry
+{
+  public:
+
+    Qgs3DSymbolRegistry();
+    ~Qgs3DSymbolRegistry();
+
+    //! Qgs3DSymbolRegistry cannot be copied.
+    Qgs3DSymbolRegistry( const Qgs3DSymbolRegistry &rh ) = delete;
+    //! Qgs3DSymbolRegistry cannot be copied.
+    Qgs3DSymbolRegistry &operator=( const Qgs3DSymbolRegistry &rh ) = delete;
+
+    //! Returns metadata for specified symbol \a type. Returns NULLPTR if not found
+    Qgs3DSymbolAbstractMetadata *symbolMetadata( const QString &type ) const;
+
+    /**
+     * Returns a list of all available symbol types.
+     */
+    QStringList symbolTypes() const;
+
+    //! Registers a new symbol type. Takes ownership of the \a metadata instance.
+    bool addSymbolType( Qgs3DSymbolAbstractMetadata *metadata SIP_TRANSFER );
+
+    /**
+     * Creates a new instance of a symbol of the specified \a type.
+     *
+     * The caller takes ownership of the returned symbol.
+     *
+     * Returns NULLPTR if the specified type is not found in the registry.
+     */
+    QgsAbstract3DSymbol *createSymbol( const QString &type ) const SIP_FACTORY;
+
+  private:
+#ifdef SIP_RUN
+    Qgs3DSymbolRegistry( const Qgs3DSymbolRegistry &rh );
+#endif
+
+    QMap<QString, Qgs3DSymbolAbstractMetadata *> mMetadata;
+};
+
+
+#endif // QGS3DSYMBOLREGISTRY_H

src/core/CMakeLists.txt

@@ -654,6 +654,7 @@ SET(QGIS_CORE_SRCS
   geometry/qgswkbtypes.cpp
 
   3d/qgs3drendererregistry.cpp
+  3d/qgs3dsymbolregistry.cpp
   3d/qgsabstract3dsymbol.cpp
   3d/qgsabstract3drenderer.cpp
 
@@ -1033,6 +1034,7 @@ SET(QGIS_CORE_HDRS
   qobjectuniqueptr.h
 
   3d/qgs3drendererregistry.h
+  3d/qgs3dsymbolregistry.h
   3d/qgsabstract3dsymbol.h
   3d/qgsabstract3drenderer.h
 

src/core/qgsapplication.cpp

@@ -54,6 +54,7 @@
 #include "qgsuserprofilemanager.h"
 #include "qgsreferencedgeometry.h"
 #include "qgs3drendererregistry.h"
+#include "qgs3dsymbolregistry.h"
 #include "qgslayoutrendercontext.h"
 #include "qgssqliteutils.h"
 #include "qgsstyle.h"
@@ -2235,6 +2236,11 @@ Qgs3DRendererRegistry *QgsApplication::renderer3DRegistry()
   return members()->m3DRendererRegistry;
 }
 
+Qgs3DSymbolRegistry *QgsApplication::symbol3DRegistry()
+{
+  return members()->m3DSymbolRegistry;
+}
+
 QgsScaleBarRendererRegistry *QgsApplication::scaleBarRendererRegistry()
 {
   return members()->mScaleBarRendererRegistry;
@@ -2355,6 +2361,11 @@ QgsApplication::ApplicationMembers::ApplicationMembers()
     mAnnotationRegistry = new QgsAnnotationRegistry();
     profiler->end();
   }
+  {
+    profiler->start( tr( "Setup 3D symbol registry" ) );
+    m3DSymbolRegistry = new Qgs3DSymbolRegistry();
+    profiler->end();
+  }
   {
     profiler->start( tr( "Setup 3D renderer registry" ) );
     m3DRendererRegistry = new Qgs3DRendererRegistry();
@@ -2399,6 +2410,7 @@ QgsApplication::ApplicationMembers::~ApplicationMembers()
   delete mValidityCheckRegistry;
   delete mActionScopeRegistry;
   delete m3DRendererRegistry;
+  delete m3DSymbolRegistry;
   delete mAnnotationRegistry;
   delete mColorSchemeRegistry;
   delete mFieldFormatterRegistry;

src/core/qgsapplication.h

@@ -60,6 +60,7 @@ class QgsStyleModel;
 class QgsNumericFormatRegistry;
 class QgsConnectionRegistry;
 class QgsScaleBarRendererRegistry;
+class Qgs3DSymbolRegistry;
 
 /**
  * \ingroup core
@@ -785,6 +786,12 @@ class CORE_EXPORT QgsApplication : public QApplication
      */
     static Qgs3DRendererRegistry *renderer3DRegistry() SIP_KEEPREFERENCE;
 
+    /**
+     * Returns registry of available 3D symbols.
+     * \since QGIS 3.16
+     */
+    static Qgs3DSymbolRegistry *symbol3DRegistry() SIP_KEEPREFERENCE;
+
     /**
      * Gets the registry of available scalebar renderers.
      *
@@ -928,6 +935,7 @@ class CORE_EXPORT QgsApplication : public QApplication
     struct ApplicationMembers
     {
       Qgs3DRendererRegistry *m3DRendererRegistry = nullptr;
+      Qgs3DSymbolRegistry *m3DSymbolRegistry = nullptr;
       QgsActionScopeRegistry *mActionScopeRegistry = nullptr;
       QgsAnnotationRegistry *mAnnotationRegistry = nullptr;
       QgsColorSchemeRegistry *mColorSchemeRegistry = nullptr;

tests/src/3d/CMakeLists.txt

@@ -79,3 +79,4 @@ ADD_QGIS_TEST(3dutilstest testqgs3dutils.cpp)
 ADD_QGIS_TEST(3drenderingtest testqgs3drendering.cpp)
 ADD_QGIS_TEST(layout3dmaptest testqgslayout3dmap.cpp)
 ADD_QGIS_TEST(tessellatortest testqgstessellator.cpp)
+ADD_QGIS_TEST(3dsymbolregistrytest testqgs3dsymbolregistry.cpp)

tests/src/3d/testqgs3dsymbolregistry.cpp

@@ -0,0 +1,155 @@
+/***************************************************************************
+                         TestQgs3DSymbolRegistry.cpp
+                         -----------------------
+    begin                : July 2019
+    copyright            : (C) 2019 by 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.                                   *
+ *                                                                         *
+ ***************************************************************************/
+
+#include "qgs3dsymbolregistry.h"
+#include "qgsabstract3dsymbol.h"
+
+#include <QObject>
+#include "qgstest.h"
+
+//dummy symbol for testing
+class Dummy3DSymbol : public QgsAbstract3DSymbol
+{
+  public:
+    Dummy3DSymbol() = default;
+    QString type() const override { return QStringLiteral( "Dummy" ); }
+    QgsAbstract3DSymbol *clone() const override { return new Dummy3DSymbol(); }
+    void writeXml( QDomElement &, const QgsReadWriteContext & ) const override {}
+    void readXml( const QDomElement &, const QgsReadWriteContext & ) override {}
+
+    static QgsAbstract3DSymbol *create() { return new Dummy3DSymbol(); }
+
+};
+
+class TestQgs3DSymbolRegistry : public QObject
+{
+    Q_OBJECT
+
+  private slots:
+    void initTestCase();
+    void cleanupTestCase();
+    void init();
+    void cleanup();
+    void metadata();
+    void createInstance();
+    void instanceHasDefaultSymbols();
+    void addSymbol();
+    void fetchTypes();
+    void createSymbol();
+
+  private:
+
+};
+
+void TestQgs3DSymbolRegistry::initTestCase()
+{
+  QgsApplication::init(); // init paths for CRS lookup
+  QgsApplication::initQgis();
+}
+
+void TestQgs3DSymbolRegistry::cleanupTestCase()
+{
+  QgsApplication::exitQgis();
+}
+
+void TestQgs3DSymbolRegistry::init()
+{
+
+}
+
+void TestQgs3DSymbolRegistry::cleanup()
+{
+
+}
+
+void TestQgs3DSymbolRegistry::metadata()
+{
+  Qgs3DSymbolMetadata metadata = Qgs3DSymbolMetadata( QStringLiteral( "name" ), QStringLiteral( "display name" ), Dummy3DSymbol::create );
+  QCOMPARE( metadata.type(), QString( "name" ) );
+  QCOMPARE( metadata.visibleName(), QString( "display name" ) );
+
+  //test creating symbol from metadata
+  QVariantMap map;
+  std::unique_ptr< QgsAbstract3DSymbol > symbol( metadata.create() );
+  QVERIFY( symbol );
+  Dummy3DSymbol *dummySymbol = dynamic_cast<Dummy3DSymbol *>( symbol.get() );
+  QVERIFY( dummySymbol );
+}
+
+void TestQgs3DSymbolRegistry::createInstance()
+{
+  Qgs3DSymbolRegistry *registry = QgsApplication::symbol3DRegistry();
+  QVERIFY( registry );
+}
+
+void TestQgs3DSymbolRegistry::instanceHasDefaultSymbols()
+{
+  //check that symbol registry is initially populated with some symbols
+  //(assumes that there is some default symbols)
+  Qgs3DSymbolRegistry *registry = QgsApplication::symbol3DRegistry();
+  QVERIFY( registry->symbolTypes().length() > 0 );
+}
+
+void TestQgs3DSymbolRegistry::addSymbol()
+{
+  Qgs3DSymbolRegistry *registry = QgsApplication::symbol3DRegistry();
+  int previousCount = registry->symbolTypes().length();
+
+  registry->addSymbolType( new Qgs3DSymbolMetadata( QStringLiteral( "Dummy" ), QStringLiteral( "Dummy symbol" ), Dummy3DSymbol::create ) );
+  QCOMPARE( registry->symbolTypes().length(), previousCount + 1 );
+  //try adding again, should have no effect
+  Qgs3DSymbolMetadata *dupe = new Qgs3DSymbolMetadata( QStringLiteral( "Dummy" ), QStringLiteral( "Dummy symbol" ), Dummy3DSymbol::create );
+  QVERIFY( ! registry->addSymbolType( dupe ) );
+  QCOMPARE( registry->symbolTypes().length(), previousCount + 1 );
+  delete dupe;
+
+  //try adding empty metadata
+  registry->addSymbolType( nullptr );
+  QCOMPARE( registry->symbolTypes().length(), previousCount + 1 );
+}
+
+void TestQgs3DSymbolRegistry::fetchTypes()
+{
+  Qgs3DSymbolRegistry *registry = QgsApplication::symbol3DRegistry();
+  QStringList types = registry->symbolTypes();
+
+  QVERIFY( types.contains( "Dummy" ) );
+
+  Qgs3DSymbolAbstractMetadata *metadata = registry->symbolMetadata( QStringLiteral( "Dummy" ) );
+  QCOMPARE( metadata->type(), QString( "Dummy" ) );
+
+  //metadata for bad symbol
+  metadata = registry->symbolMetadata( QStringLiteral( "bad symbol" ) );
+  QVERIFY( !metadata );
+}
+
+void TestQgs3DSymbolRegistry::createSymbol()
+{
+  Qgs3DSymbolRegistry *registry = QgsApplication::symbol3DRegistry();
+  std::unique_ptr< QgsAbstract3DSymbol > symbol( registry->createSymbol( QStringLiteral( "Dummy" ) ) );
+
+  QVERIFY( symbol.get() );
+  Dummy3DSymbol *dummySymbol = dynamic_cast<Dummy3DSymbol *>( symbol.get() );
+  QVERIFY( dummySymbol );
+
+  //try creating a bad symbol
+  symbol.reset( registry->createSymbol( QStringLiteral( "bad symbol" ) ) );
+  QVERIFY( !symbol.get() );
+}
+
+QGSTEST_MAIN( TestQgs3DSymbolRegistry )
+#include "testqgs3dsymbolregistry.moc"