Move default legend patch shape handling to QgsStyle

python/core/auto_generated/layertree/qgslegendpatchshape.sip.in

@@ -116,11 +116,6 @@ The default behavior is to respect the geometry()'s aspect ratio.
 Converts the patch shape to a set of QPolygonF objects representing
 how the patch should be drawn for a symbol of the given ``type`` at the specified ``size`` (as
 geometry parts and rings).
-%End
-
-    static QList< QList< QPolygonF > > defaultPatch( QgsSymbol::SymbolType type, QSizeF size );
-%Docstring
-Returns the default patch geometry for the given symbol ``type`` and ``size`` as a set of QPolygonF objects (parts and rings).
 %End
 
     void readXml( const QDomElement &element, const QgsReadWriteContext &context );

python/core/auto_generated/symbology/qgsstyle.sip.in

@@ -552,6 +552,24 @@ Removes label settings from the style.
 Changes a label setting's name.
 
 .. versionadded:: 3.10
+%End
+
+    QgsLegendPatchShape defaultPatch( QgsSymbol::SymbolType type, QSizeF size ) const;
+%Docstring
+Returns the default legend patch shape for the given symbol ``type``.
+
+.. seealso:: :py:func:`defaultPatchAsQPolygonF`
+
+.. versionadded:: 3.14
+%End
+
+    QList< QList< QPolygonF > > defaultPatchAsQPolygonF( QgsSymbol::SymbolType type, QSizeF size ) const;
+%Docstring
+Returns the default patch geometry for the given symbol ``type`` and ``size`` as a set of QPolygonF objects (parts and rings).
+
+.. seealso:: :py:func:`defaultPatch`
+
+.. versionadded:: 3.14
 %End
 
     bool createDatabase( const QString &filename );

src/core/layertree/qgslegendpatchshape.cpp

@@ -19,6 +19,7 @@ email                : nyall dot dawson at gmail dot com
 #include "qgsmultilinestring.h"
 #include "qgslinestring.h"
 #include "qgspolygon.h"
+#include "qgsstyle.h"
 
 QgsLegendPatchShape::QgsLegendPatchShape( QgsSymbol::SymbolType type, const QgsGeometry &geometry, bool preserveAspectRatio )
   : mSymbolType( type )
@@ -83,7 +84,7 @@ QPolygonF curveToPolygonF( const QgsCurve *curve )
 QList<QList<QPolygonF> > QgsLegendPatchShape::toQPolygonF( QgsSymbol::SymbolType type, QSizeF size ) const
 {
   if ( isNull() || type != mSymbolType )
-    return defaultPatch( type, size );
+    return QgsStyle::defaultStyle()->defaultPatchAsQPolygonF( type, size );
 
   // scale and translate to desired size
 
@@ -128,7 +129,7 @@ QList<QList<QPolygonF> > QgsLegendPatchShape::toQPolygonF( QgsSymbol::SymbolType
       }
       else
       {
-        points << QPointF( size.width() / 2, size.height() / 2 );
+        points << QPointF( static_cast< int >( size.width() ) / 2, static_cast< int >( size.height() ) / 2 );
       }
       return QList< QList<QPolygonF> >() << ( QList< QPolygonF >() << points );
     }
@@ -176,29 +177,6 @@ QList<QList<QPolygonF> > QgsLegendPatchShape::toQPolygonF( QgsSymbol::SymbolType
   return QList< QList<QPolygonF> >();
 }
 
-QList<QList<QPolygonF> > QgsLegendPatchShape::defaultPatch( QgsSymbol::SymbolType type, QSizeF size )
-{
-  switch ( type )
-  {
-    case QgsSymbol::Marker:
-      return QList< QList< QPolygonF > >() << ( QList< QPolygonF >() << ( QPolygonF() << QPointF( static_cast< int >( size.width() ) / 2,
-             static_cast< int >( size.height() ) / 2 ) ) );
-
-    case QgsSymbol::Line:
-      // we're adding 0.5 to get rid of blurred preview:
-      // drawing antialiased lines of width 1 at (x,0)-(x,100) creates 2px line
-      return QList< QList<QPolygonF> >() << ( QList< QPolygonF >() << ( QPolygonF()  << QPointF( 0, static_cast< int >( size.height() ) / 2 + 0.5 ) << QPointF( size.width(), static_cast< int >( size.height() ) / 2 + 0.5 ) ) );
-
-    case QgsSymbol::Fill:
-      return QList< QList<QPolygonF> >() << ( QList< QPolygonF> () << ( QRectF( QPointF( 0, 0 ), QPointF( static_cast< int >( size.width() ), static_cast< int >( size.height() ) ) ) ) );
-
-    case QgsSymbol::Hybrid:
-      return QList< QList<QPolygonF> >();
-  }
-
-  return QList< QList<QPolygonF> >();
-}
-
 void QgsLegendPatchShape::readXml( const QDomElement &element, const QgsReadWriteContext & )
 {
   mGeometry = QgsGeometry::fromWkt( element.attribute( QStringLiteral( "wkt" ) ) );

src/core/layertree/qgslegendpatchshape.h

@@ -126,11 +126,6 @@ class CORE_EXPORT QgsLegendPatchShape
      */
     QList< QList< QPolygonF > > toQPolygonF( QgsSymbol::SymbolType type, QSizeF size ) const;
 
-    /**
-     * Returns the default patch geometry for the given symbol \a type and \a size as a set of QPolygonF objects (parts and rings).
-     */
-    static QList< QList< QPolygonF > > defaultPatch( QgsSymbol::SymbolType type, QSizeF size );
-
     /**
      * Read settings from a DOM \a element.
      * \see writeXml()

src/core/symbology/qgsstyle.cpp

@@ -22,6 +22,9 @@
 #include "qgslogger.h"
 #include "qgsreadwritecontext.h"
 #include "qgssettings.h"
+#include "qgslegendpatchshape.h"
+#include "qgslinestring.h"
+#include "qgspolygon.h"
 
 #include <QDomDocument>
 #include <QDomElement>
@@ -921,6 +924,61 @@ bool QgsStyle::renameLabelSettings( const QString &oldName, const QString &newNa
   return result;
 }
 
+QgsLegendPatchShape QgsStyle::defaultPatch( QgsSymbol::SymbolType type, QSizeF size ) const
+{
+  if ( type == QgsSymbol::Hybrid )
+    return QgsLegendPatchShape();
+
+  if ( mDefaultPatchCache[ type ].contains( size ) )
+    return mDefaultPatchCache[ type ].value( size );
+
+  QgsGeometry geom;
+  switch ( type )
+  {
+    case QgsSymbol::Marker:
+      geom = QgsGeometry( qgis::make_unique< QgsPoint >( static_cast< int >( size.width() ) / 2, static_cast< int >( size.height() ) / 2 ) );
+      break;
+
+    case QgsSymbol::Line:
+    {
+      // we're adding 0.5 to get rid of blurred preview:
+      // drawing antialiased lines of width 1 at (x,0)-(x,100) creates 2px line
+      double y = static_cast< int >( size.height() ) / 2 + 0.5;
+      geom = QgsGeometry( qgis::make_unique< QgsLineString >( ( QVector< double >() << 0 << size.width() ),
+                          ( QVector< double >() << y << y ) ) );
+      break;
+    }
+
+    case QgsSymbol::Fill:
+    {
+      geom = QgsGeometry( qgis::make_unique< QgsPolygon >(
+                            new QgsLineString( QVector< double >() << 0 << static_cast< int >( size.width() ) << static_cast< int >( size.width() ) << 0 << 0,
+                                QVector< double >() << static_cast< int >( size.height() ) << static_cast< int >( size.height() ) << 0 << 0 << static_cast< int >( size.height() ) ) ) );
+      break;
+    }
+
+    case QgsSymbol::Hybrid:
+      break;
+  }
+
+  QgsLegendPatchShape res = QgsLegendPatchShape( type, geom, true );
+  mDefaultPatchCache[ type ][size ] = res;
+  return res;
+}
+
+QList<QList<QPolygonF> > QgsStyle::defaultPatchAsQPolygonF( QgsSymbol::SymbolType type, QSizeF size ) const
+{
+  if ( type == QgsSymbol::Hybrid )
+    return QList<QList<QPolygonF> >();
+
+  if ( mDefaultPatchQPolygonFCache[ type ].contains( size ) )
+    return mDefaultPatchQPolygonFCache[ type ].value( size );
+
+  QList<QList<QPolygonF> > res = defaultPatch( type, size ).toQPolygonF( type, size );
+  mDefaultPatchQPolygonFCache[ type ][size ] = res;
+  return res;
+}
+
 QStringList QgsStyle::symbolsOfFavorite( StyleEntity type ) const
 {
   if ( !mCurrentDB )

src/core/symbology/qgsstyle.h

@@ -28,6 +28,7 @@
 #include "qgssymbollayerutils.h" // QgsStringMap
 #include "qgstextrenderer.h"
 #include "qgspallabeling.h"
+#include "layertree/qgslegendpatchshape.h"
 
 class QgsSymbol;
 class QgsSymbolLayer;
@@ -584,6 +585,22 @@ class CORE_EXPORT QgsStyle : public QObject
      */
     bool renameLabelSettings( const QString &oldName, const QString &newName );
 
+    /**
+     * Returns the default legend patch shape for the given symbol \a type.
+     *
+     * \see defaultPatchAsQPolygonF()
+     * \since QGIS 3.14
+     */
+    QgsLegendPatchShape defaultPatch( QgsSymbol::SymbolType type, QSizeF size ) const;
+
+    /**
+     * Returns the default patch geometry for the given symbol \a type and \a size as a set of QPolygonF objects (parts and rings).
+     *
+     * \see defaultPatch()
+     * \since QGIS 3.14
+     */
+    QList< QList< QPolygonF > > defaultPatchAsQPolygonF( QgsSymbol::SymbolType type, QSizeF size ) const;
+
     /**
      * Creates an on-disk database
      *
@@ -911,6 +928,9 @@ class CORE_EXPORT QgsStyle : public QObject
 
     sqlite3_database_unique_ptr mCurrentDB;
 
+    mutable QHash< QgsSymbol::SymbolType, QHash< QSizeF, QgsLegendPatchShape > > mDefaultPatchCache;
+    mutable QHash< QgsSymbol::SymbolType, QHash< QSizeF, QList< QList< QPolygonF > > > > mDefaultPatchQPolygonFCache;
+
     static QgsStyle *sDefaultStyle;
 
     //! Convenience function to open the DB and return a sqlite3 object

src/core/symbology/qgssymbol.cpp

@@ -549,7 +549,7 @@ void QgsSymbol::drawPreviewIcon( QPainter *painter, QSize size, QgsRenderContext
         const QSizeF targetSize = QSizeF( size.width() - 1, size.height() - 1 );
 
         const QList< QList< QPolygonF > > polys = patchShape ? patchShape->toQPolygonF( QgsSymbol::Fill, targetSize )
-            : QgsLegendPatchShape::defaultPatch( QgsSymbol::Fill, targetSize );
+            : QgsStyle::defaultStyle()->defaultPatchAsQPolygonF( QgsSymbol::Fill, targetSize );
 
         lsl->startRender( symbolContext );
         QgsPaintEffect *effect = lsl->paintEffect();

src/core/symbology/qgssymbollayer.cpp

@@ -29,6 +29,7 @@
 #include "qgsapplication.h"
 #include "qgsmultipoint.h"
 #include "qgslegendpatchshape.h"
+#include "qgsstyle.h"
 
 #include <QSize>
 #include <QPainter>
@@ -453,7 +454,7 @@ void QgsMarkerSymbolLayer::drawPreviewIcon( QgsSymbolRenderContext &context, QSi
   QgsPaintEffect *effect = paintEffect();
 
   QPolygonF points = context.patchShape() ? context.patchShape()->toQPolygonF( QgsSymbol::Marker, size ).value( 0 ).value( 0 )
-                     : QgsLegendPatchShape::defaultPatch( QgsSymbol::Marker, size ).value( 0 ).value( 0 );
+                     : QgsStyle::defaultStyle()->defaultPatchAsQPolygonF( QgsSymbol::Marker, size ).value( 0 ).value( 0 );
 
   std::unique_ptr< QgsEffectPainter > effectPainter;
   if ( effect && effect->enabled() )
@@ -640,7 +641,7 @@ QgsMapUnitScale QgsLineSymbolLayer::mapUnitScale() const
 void QgsLineSymbolLayer::drawPreviewIcon( QgsSymbolRenderContext &context, QSize size )
 {
   const QList< QList< QPolygonF > > points = context.patchShape() ? context.patchShape()->toQPolygonF( QgsSymbol::Line, size )
-      : QgsLegendPatchShape::defaultPatch( QgsSymbol::Line, size );
+      : QgsStyle::defaultStyle()->defaultPatchAsQPolygonF( QgsSymbol::Line, size );
   startRender( context );
   QgsPaintEffect *effect = paintEffect();
 
@@ -700,7 +701,7 @@ double QgsLineSymbolLayer::dxfWidth( const QgsDxfExport &e, QgsSymbolRenderConte
 void QgsFillSymbolLayer::drawPreviewIcon( QgsSymbolRenderContext &context, QSize size )
 {
   const QList< QList< QPolygonF > > polys = context.patchShape() ? context.patchShape()->toQPolygonF( QgsSymbol::Fill, size )
-      : QgsLegendPatchShape::defaultPatch( QgsSymbol::Fill, size );
+      : QgsStyle::defaultStyle()->defaultPatchAsQPolygonF( QgsSymbol::Fill, size );
 
   startRender( context );
   QgsPaintEffect *effect = paintEffect();

tests/src/python/test_qgslegendpatchshape.py

@@ -28,7 +28,8 @@ from qgis.core import (QgsLegendPatchShape,
                        QgsMarkerSymbol,
                        QgsRenderChecker,
                        QgsReadWriteContext,
-                       QgsRenderContext
+                       QgsRenderContext,
+                       QgsStyle
                        )
 from qgis.PyQt.QtXml import QDomDocument, QDomElement
 
@@ -83,28 +84,28 @@ class TestQgsLegendPatchShape(unittest.TestCase):
         self.assertTrue(shape.isNull())
 
     def testDefault(self):
-        self.assertEqual(QgsLegendPatchShape.defaultPatch(QgsSymbol.Hybrid, QSizeF(1, 1)), [])
-        self.assertEqual(QgsLegendPatchShape.defaultPatch(QgsSymbol.Hybrid, QSizeF(10, 10)), [])
+        self.assertEqual(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Hybrid, QSizeF(1, 1)), [])
+        self.assertEqual(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Hybrid, QSizeF(10, 10)), [])
 
         # markers
-        self.assertEqual(self.polys_to_list(QgsLegendPatchShape.defaultPatch(QgsSymbol.Marker, QSizeF(1, 1))), [[[[0.0, 0.0]]]])
-        self.assertEqual(self.polys_to_list(QgsLegendPatchShape.defaultPatch(QgsSymbol.Marker, QSizeF(2, 2))),
+        self.assertEqual(self.polys_to_list(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Marker, QSizeF(1, 1))), [[[[0.0, 0.0]]]])
+        self.assertEqual(self.polys_to_list(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Marker, QSizeF(2, 2))),
                          [[[[1.0, 1.0]]]])
-        self.assertEqual(self.polys_to_list(QgsLegendPatchShape.defaultPatch(QgsSymbol.Marker, QSizeF(10, 2))), [[[[5.0, 1.0]]]])
+        self.assertEqual(self.polys_to_list(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Marker, QSizeF(10, 2))), [[[[5.0, 1.0]]]])
 
         # lines
-        self.assertEqual(self.polys_to_list(QgsLegendPatchShape.defaultPatch(QgsSymbol.Line, QSizeF(1, 1))), [[[[0.0, 0.5], [1.0, 0.5]]]])
-        self.assertEqual(self.polys_to_list(QgsLegendPatchShape.defaultPatch(QgsSymbol.Line, QSizeF(10, 2))), [[[[0.0, 1.5], [10.0, 1.5]]]])
-        self.assertEqual(self.polys_to_list(QgsLegendPatchShape.defaultPatch(QgsSymbol.Line, QSizeF(9, 3))), [[[[0.0, 1.5], [9.0, 1.5]]]])
+        self.assertEqual(self.polys_to_list(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Line, QSizeF(1, 1))), [[[[0.0, 0.5], [1.0, 0.5]]]])
+        self.assertEqual(self.polys_to_list(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Line, QSizeF(10, 2))), [[[[0.0, 1.5], [10.0, 1.5]]]])
+        self.assertEqual(self.polys_to_list(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Line, QSizeF(9, 3))), [[[[0.0, 1.5], [9.0, 1.5]]]])
 
         # fills
-        self.assertEqual(self.polys_to_list(QgsLegendPatchShape.defaultPatch(QgsSymbol.Fill, QSizeF(1, 1))), [[[[0.0, 0.0], [1.0, 0.0], [1.0, 1.0], [0.0, 1.0], [0.0, 0.0]]]])
-        self.assertEqual(self.polys_to_list(QgsLegendPatchShape.defaultPatch(QgsSymbol.Fill, QSizeF(10, 2))), [[[[0.0, 0.0], [10.0, 0.0], [10.0, 2.0], [0.0, 2.0], [0.0, 0.0]]]])
+        self.assertEqual(self.polys_to_list(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Fill, QSizeF(1, 1))), [[[[0.0, 0.0], [1.0, 0.0], [1.0, 1.0], [0.0, 1.0], [0.0, 0.0]]]])
+        self.assertEqual(self.polys_to_list(QgsStyle.defaultStyle().defaultPatchAsQPolygonF(QgsSymbol.Fill, QSizeF(10, 2))), [[[[0.0, 0.0], [10.0, 0.0], [10.0, 2.0], [0.0, 2.0], [0.0, 0.0]]]])
 
     def testMarkers(self):
         # shouldn't matter what a point geometry is, it will always be rendered in center of symbol patch
         shape = QgsLegendPatchShape(QgsSymbol.Marker, QgsGeometry.fromWkt('Point( 5 5 )'), False)
-        self.assertEqual(self.polys_to_list(shape.toQPolygonF(QgsSymbol.Marker, QSizeF(1, 1))), [[[[0.5, 0.5]]]])
+        self.assertEqual(self.polys_to_list(shape.toQPolygonF(QgsSymbol.Marker, QSizeF(1, 1))), [[[[0, 0]]]])
         self.assertEqual(self.polys_to_list(shape.toQPolygonF(QgsSymbol.Marker, QSizeF(10, 2))), [[[[5.0, 1.0]]]])
 
         # requesting different symbol type, should return default