Make coordinates of vector data chunks independent from scene origin

This is a continuation of work started in qgis#58948, handling all the cases
of data from vector layers.

src/3d/qgs3dutils.cpp

@@ -488,7 +488,7 @@ QMatrix4x4 Qgs3DUtils::stringToMatrix4x4( const QString &str )
   return m;
 }
 
-void Qgs3DUtils::extractPointPositions( const QgsFeature &f, const Qgs3DRenderContext &context, Qgis::AltitudeClamping altClamp, QVector<QVector3D> &positions )
+void Qgs3DUtils::extractPointPositions( const QgsFeature &f, const Qgs3DRenderContext &context, const QgsVector3D &chunkOrigin, Qgis::AltitudeClamping altClamp, QVector<QVector3D> &positions )
 {
   const QgsAbstractGeometry *g = f.geometry().constGet();
   for ( auto it = g->vertices_begin(); it != g->vertices_end(); ++it )
@@ -513,7 +513,7 @@ void Qgs3DUtils::extractPointPositions( const QgsFeature &f, const Qgs3DRenderCo
         h = terrainZ + geomZ;
         break;
     }
-    positions.append( QVector3D( pt.x() - context.origin().x(), h, -( pt.y() - context.origin().y() ) ) );
+    positions.append( QVector3D( pt.x() - chunkOrigin.x(), h, -( pt.y() - chunkOrigin.y() ) ) );
     QgsDebugMsgLevel( QStringLiteral( "%1 %2 %3" ).arg( positions.last().x() ).arg( positions.last().y() ).arg( positions.last().z() ), 2 );
   }
 }

src/3d/qgs3dutils.h

@@ -143,7 +143,7 @@ class _3D_EXPORT Qgs3DUtils
     static QMatrix4x4 stringToMatrix4x4( const QString &str );
 
     //! Calculates (x,y,z) positions of (multi)point from the given feature
-    static void extractPointPositions( const QgsFeature &f, const Qgs3DRenderContext &context, Qgis::AltitudeClamping altClamp, QVector<QVector3D> &positions );
+    static void extractPointPositions( const QgsFeature &f, const Qgs3DRenderContext &context, const QgsVector3D &chunkOrigin, Qgis::AltitudeClamping altClamp, QVector<QVector3D> &positions );
 
     /**
      * Returns TRUE if bbox is completely outside the current viewing volume.

src/3d/qgsfeature3dhandler_p.h

@@ -49,7 +49,7 @@ class QgsFeature3DHandler
      * Called before feature iteration starts to initialize, get required attributes.
      * \returns TRUE on success (on FALSE the handler failed to initialize and processFeature() / finalize() should not be called
      */
-    virtual bool prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames ) = 0;
+    virtual bool prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames, const QgsVector3D &chunkOrigin ) = 0;
 
     /**
      * Called for every feature to extract information out of it into some

src/3d/qgsrubberband3d.cpp

@@ -167,7 +167,7 @@ void QgsRubberBand3D::updateGeometry()
 {
   QgsLineVertexData lineData;
   lineData.withAdjacency = true;
-  lineData.init( Qgis::AltitudeClamping::Absolute, Qgis::AltitudeBinding::Vertex, 0, Qgs3DRenderContext::fromMapSettings( mMapSettings ) );
+  lineData.init( Qgis::AltitudeClamping::Absolute, Qgis::AltitudeBinding::Vertex, 0, Qgs3DRenderContext::fromMapSettings( mMapSettings ), mMapSettings->origin() );
   lineData.addLineString( mLineString );
 
   mPositionAttribute->buffer()->setData( lineData.createVertexBuffer() );

src/3d/qgsrulebased3drenderer.cpp

@@ -262,12 +262,12 @@ void QgsRuleBased3DRenderer::Rule::createHandlers( QgsVectorLayer *layer, QgsRul
 }
 
 
-void QgsRuleBased3DRenderer::Rule::prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames, QgsRuleBased3DRenderer::RuleToHandlerMap &handlers ) const
+void QgsRuleBased3DRenderer::Rule::prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames, const QgsVector3D &chunkOrigin,  QgsRuleBased3DRenderer::RuleToHandlerMap &handlers ) const
 {
   if ( mSymbol )
   {
     QgsFeature3DHandler *handler = handlers[this];
-    if ( !handler->prepare( context, attributeNames ) )
+    if ( !handler->prepare( context, attributeNames, chunkOrigin ) )
     {
       handlers.remove( this );
       delete handler;
@@ -283,7 +283,7 @@ void QgsRuleBased3DRenderer::Rule::prepare( const Qgs3DRenderContext &context, Q
   // call recursively
   for ( Rule *rule : std::as_const( mChildren ) )
   {
-    rule->prepare( context, attributeNames, handlers );
+    rule->prepare( context, attributeNames, chunkOrigin, handlers );
   }
 }
 

src/3d/qgsrulebased3drenderer.h

@@ -242,7 +242,7 @@ class _3D_EXPORT QgsRuleBased3DRenderer : public QgsAbstractVectorLayer3DRendere
          * call prepare() on handlers and populate attributeNames
          * \note not available in Python bindings
          */
-        void prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames, RuleToHandlerMap &handlers ) const SIP_SKIP;
+        void prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames, const QgsVector3D &chunkOrigin, RuleToHandlerMap &handlers ) const SIP_SKIP;
 
         /**
          * register individual features

src/3d/qgsrulebasedchunkloader_p.cpp

@@ -50,6 +50,12 @@ QgsRuleBasedChunkLoader::QgsRuleBasedChunkLoader( const QgsRuleBasedChunkLoaderF
 
   QgsVectorLayer *layer = mFactory->mLayer;
 
+  // only a subset of data to be queried
+  const QgsRectangle rect = Qgs3DUtils::worldToMapExtent( node->bbox(), mContext.origin() );
+  // origin for coordinates of the chunk - it is kind of arbitrary, but it should be
+  // picked so that the coordinates are relatively small to avoid numerical precision issues
+  QgsVector3D chunkOrigin( rect.center().x(), rect.center().y(), 0 );
+
   QgsExpressionContext exprContext( Qgs3DUtils::globalProjectLayerExpressionContext( layer ) );
   exprContext.setFields( layer->fields() );
   mContext.setExpressionContext( exprContext );
@@ -63,15 +69,12 @@ QgsRuleBasedChunkLoader::QgsRuleBasedChunkLoader( const QgsRuleBasedChunkLoaderF
   mRootRule->createHandlers( layer, mHandlers );
 
   QSet<QString> attributeNames;
-  mRootRule->prepare( mContext, attributeNames, mHandlers );
+  mRootRule->prepare( mContext, attributeNames, chunkOrigin, mHandlers );
 
   // build the feature request
   QgsFeatureRequest req;
   req.setDestinationCrs( mContext.crs(), mContext.transformContext() );
   req.setSubsetOfAttributes( attributeNames, layer->fields() );
-
-  // only a subset of data to be queried
-  const QgsRectangle rect = Qgs3DUtils::worldToMapExtent( node->bbox(), mContext.origin() );
   req.setFilterRect( rect );
 
   //

src/3d/qgstessellatedpolygongeometry.cpp

@@ -82,42 +82,6 @@ QgsTessellatedPolygonGeometry::QgsTessellatedPolygonGeometry( bool _withNormals,
   }
 }
 
-void QgsTessellatedPolygonGeometry::setPolygons( const QList<QgsPolygon *> &polygons, const QList<QgsFeatureId> &featureIds, const QgsPointXY &origin, float extrusionHeight, const QList<float> &extrusionHeightPerPolygon )
-{
-  Q_ASSERT( polygons.count() == featureIds.count() );
-  mTriangleIndexStartingIndices.reserve( polygons.count() );
-  mTriangleIndexFids.reserve( polygons.count() );
-
-  QgsTessellator tessellator( origin.x(), origin.y(), mWithNormals, mInvertNormals, mAddBackFaces, false, mAddTextureCoords );
-  for ( int i = 0; i < polygons.count(); ++i )
-  {
-    Q_ASSERT( tessellator.dataVerticesCount() % 3 == 0 );
-    const uint startingTriangleIndex = static_cast<uint>( tessellator.dataVerticesCount() / 3 );
-    mTriangleIndexStartingIndices.append( startingTriangleIndex );
-    mTriangleIndexFids.append( featureIds[i] );
-
-    QgsPolygon *polygon = polygons.at( i );
-    const float extr = extrusionHeightPerPolygon.isEmpty() ? extrusionHeight : extrusionHeightPerPolygon.at( i );
-    tessellator.addPolygon( *polygon, extr );
-  }
-  if ( !tessellator.error().isEmpty() )
-  {
-    QgsMessageLog::logMessage( tessellator.error(), QObject::tr( "3D" ) );
-  }
-
-  qDeleteAll( polygons );
-
-  const QByteArray data( ( const char * )tessellator.data().constData(), tessellator.data().count() * sizeof( float ) );
-  const int nVerts = data.count() / tessellator.stride();
-
-  mVertexBuffer->setData( data );
-  mPositionAttribute->setCount( nVerts );
-  if ( mNormalAttribute )
-    mNormalAttribute->setCount( nVerts );
-  if ( mAddTextureCoords )
-    mTextureCoordsAttribute->setCount( nVerts );
-}
-
 void QgsTessellatedPolygonGeometry::setData( const QByteArray &vertexBufferData, int vertexCount, const QVector<QgsFeatureId> &triangleIndexFids, const QVector<uint> &triangleIndexStartingIndices )
 {
   mTriangleIndexStartingIndices = triangleIndexStartingIndices;

src/3d/qgstessellatedpolygongeometry.h

@@ -91,9 +91,6 @@ class QgsTessellatedPolygonGeometry : public Qt3DCore::QGeometry
      */
     void setAddTextureCoords( bool add ) { mAddTextureCoords = add; }
 
-    //! Initializes vertex buffer from given polygons. Takes ownership of passed polygon geometries
-    void setPolygons( const QList<QgsPolygon *> &polygons, const QList<QgsFeatureId> &featureIds, const QgsPointXY &origin, float extrusionHeight, const QList<float> &extrusionHeightPerPolygon = QList<float>() );
-
     /**
      * Initializes vertex buffer (and other members) from data that were already tessellated.
      * This is an alternative to setPolygons() - this method does not do any expensive work in the body.

src/3d/qgsvectorlayerchunkloader_p.cpp

@@ -59,12 +59,18 @@ QgsVectorLayerChunkLoader::QgsVectorLayerChunkLoader( const QgsVectorLayerChunkL
   }
   mHandler.reset( handler );
 
+  // only a subset of data to be queried
+  const QgsRectangle rect = Qgs3DUtils::worldToMapExtent( node->bbox(), mRenderContext.origin() );
+  // origin for coordinates of the chunk - it is kind of arbitrary, but it should be
+  // picked so that the coordinates are relatively small to avoid numerical precision issues
+  QgsVector3D chunkOrigin( rect.center().x(), rect.center().y(), 0 );
+
   QgsExpressionContext exprContext( Qgs3DUtils::globalProjectLayerExpressionContext( layer ) );
   exprContext.setFields( layer->fields() );
   mRenderContext.setExpressionContext( exprContext );
 
   QSet<QString> attributeNames;
-  if ( !mHandler->prepare( mRenderContext, attributeNames ) )
+  if ( !mHandler->prepare( mRenderContext, attributeNames, chunkOrigin ) )
   {
     QgsDebugError( QStringLiteral( "Failed to prepare 3D feature handler!" ) );
     return;
@@ -76,9 +82,6 @@ QgsVectorLayerChunkLoader::QgsVectorLayerChunkLoader( const QgsVectorLayerChunkL
     QgsCoordinateTransform( layer->crs3D(), mRenderContext.crs(), mRenderContext.transformContext() )
   );
   req.setSubsetOfAttributes( attributeNames, layer->fields() );
-
-  // only a subset of data to be queried
-  const QgsRectangle rect = Qgs3DUtils::worldToMapExtent( node->bbox(), mRenderContext.origin() );
   req.setFilterRect( rect );
 
   //

src/3d/symbols/qgsline3dsymbol_p.cpp

@@ -33,6 +33,7 @@
 #include "qgsphongtexturedmaterialsettings.h"
 #include "qgsmessagelog.h"
 
+#include <Qt3DCore/QTransform>
 #include <Qt3DExtras/QPhongMaterial>
 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
 #include <Qt3DRender/QAttribute>
@@ -63,7 +64,7 @@ class QgsBufferedLine3DSymbolHandler : public QgsFeature3DHandler
       : mSymbol( static_cast< QgsLine3DSymbol *>( symbol->clone() ) )
       , mSelectedIds( selectedIds ) {}
 
-    bool prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames ) override;
+    bool prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames, const QgsVector3D &chunkOrigin ) override;
     void processFeature( const QgsFeature &feature, const Qgs3DRenderContext &context ) override;
     void finalize( Qt3DCore::QEntity *parent, const Qgs3DRenderContext &context ) override;
 
@@ -86,24 +87,29 @@ class QgsBufferedLine3DSymbolHandler : public QgsFeature3DHandler
     // inputs - generic
     QgsFeatureIds mSelectedIds;
 
+    //! origin (in the map coordinates) for output geometries (e.g. at the center of the chunk)
+    QgsVector3D mChunkOrigin;
+
     // outputs
     LineData outNormal;  //!< Features that are not selected
     LineData outSelected;  //!< Features that are selected
 };
 
 
 
-bool QgsBufferedLine3DSymbolHandler::prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames )
+bool QgsBufferedLine3DSymbolHandler::prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames, const QgsVector3D &chunkOrigin )
 {
   Q_UNUSED( attributeNames )
 
+  mChunkOrigin = chunkOrigin;
+
   const QgsPhongTexturedMaterialSettings *texturedMaterialSettings = dynamic_cast< const QgsPhongTexturedMaterialSettings * >( mSymbol->materialSettings() );
 
-  outNormal.tessellator.reset( new QgsTessellator( context.origin().x(), context.origin().y(), true,
+  outNormal.tessellator.reset( new QgsTessellator( chunkOrigin.x(), chunkOrigin.y(), true,
                                false, false, false, texturedMaterialSettings ? texturedMaterialSettings->requiresTextureCoordinates() : false,
                                3,
                                texturedMaterialSettings ? texturedMaterialSettings->textureRotation() : 0 ) );
-  outSelected.tessellator.reset( new QgsTessellator( context.origin().x(), context.origin().y(), true,
+  outSelected.tessellator.reset( new QgsTessellator( chunkOrigin.x(), chunkOrigin.y(), true,
                                  false, false, false, texturedMaterialSettings ? texturedMaterialSettings->requiresTextureCoordinates() : false,
                                  3,
                                  texturedMaterialSettings ? texturedMaterialSettings->textureRotation() : 0 ) );
@@ -217,10 +223,16 @@ void QgsBufferedLine3DSymbolHandler::makeEntity( Qt3DCore::QEntity *parent, cons
   Qt3DRender::QGeometryRenderer *renderer = new Qt3DRender::QGeometryRenderer;
   renderer->setGeometry( geometry );
 
+  // add transform (our geometry has coordinates relative to mChunkOrigin)
+  Qt3DCore::QTransform *tr = new Qt3DCore::QTransform;
+  QVector3D nodeTranslation = ( mChunkOrigin - context.origin() ).toVector3D();
+  tr->setTranslation( QVector3D( nodeTranslation.x(), nodeTranslation.z(), -nodeTranslation.y() ) );
+
   // make entity
   Qt3DCore::QEntity *entity = new Qt3DCore::QEntity;
   entity->addComponent( renderer );
   entity->addComponent( mat );
+  entity->addComponent( tr );
   entity->setParent( parent );
 
   if ( !selected )
@@ -243,7 +255,7 @@ class QgsThickLine3DSymbolHandler : public QgsFeature3DHandler
     {
     }
 
-    bool prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames ) override;
+    bool prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames, const QgsVector3D &chunkOrigin ) override;
     void processFeature( const QgsFeature &feature, const Qgs3DRenderContext &context ) override;
     void finalize( Qt3DCore::QEntity *parent, const Qgs3DRenderContext &context ) override;
 
@@ -259,21 +271,26 @@ class QgsThickLine3DSymbolHandler : public QgsFeature3DHandler
     // inputs - generic
     QgsFeatureIds mSelectedIds;
 
+    //! origin (in the map coordinates) for output geometries (e.g. at the center of the chunk)
+    QgsVector3D mChunkOrigin;
+
     // outputs
     QgsLineVertexData outNormal;  //!< Features that are not selected
     QgsLineVertexData outSelected;  //!< Features that are selected
 };
 
 
 
-bool QgsThickLine3DSymbolHandler::prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames )
+bool QgsThickLine3DSymbolHandler::prepare( const Qgs3DRenderContext &context, QSet<QString> &attributeNames, const QgsVector3D &chunkOrigin )
 {
   Q_UNUSED( attributeNames )
 
+  mChunkOrigin = chunkOrigin;
+
   outNormal.withAdjacency = true;
   outSelected.withAdjacency = true;
-  outNormal.init( mSymbol->altitudeClamping(), mSymbol->altitudeBinding(), mSymbol->offset(), context );
-  outSelected.init( mSymbol->altitudeClamping(), mSymbol->altitudeBinding(), mSymbol->offset(), context );
+  outNormal.init( mSymbol->altitudeClamping(), mSymbol->altitudeBinding(), mSymbol->offset(), context, chunkOrigin );
+  outSelected.init( mSymbol->altitudeClamping(), mSymbol->altitudeBinding(), mSymbol->offset(), context, chunkOrigin );
 
   QSet<QString> attrs = mSymbol->dataDefinedProperties().referencedFields( context.expressionContext() );
   attributeNames.unite( attrs );
@@ -374,9 +391,15 @@ void QgsThickLine3DSymbolHandler::makeEntity( Qt3DCore::QEntity *parent, const Q
   renderer->setPrimitiveRestartEnabled( true );
   renderer->setRestartIndexValue( 0 );
 
+  // add transform (our geometry has coordinates relative to mChunkOrigin)
+  Qt3DCore::QTransform *tr = new Qt3DCore::QTransform;
+  QVector3D nodeTranslation = ( mChunkOrigin - context.origin() ).toVector3D();
+  tr->setTranslation( QVector3D( nodeTranslation.x(), nodeTranslation.z(), -nodeTranslation.y() ) );
+
   // make entity
   entity->addComponent( renderer );
   entity->addComponent( mat );
+  entity->addComponent( tr );
   entity->setParent( parent );
 }
 

src/3d/symbols/qgslinevertexdata_p.cpp

@@ -46,12 +46,13 @@ QgsLineVertexData::QgsLineVertexData()
   vertices << QVector3D();
 }
 
-void QgsLineVertexData::init( Qgis::AltitudeClamping clamping, Qgis::AltitudeBinding binding, float height, const Qgs3DRenderContext &context )
+void QgsLineVertexData::init( Qgis::AltitudeClamping clamping, Qgis::AltitudeBinding binding, float height, const Qgs3DRenderContext &context, const QgsVector3D &chunkOrigin )
 {
   altClamping = clamping;
   altBinding = binding;
   baseHeight = height;
   renderContext = context;
+  origin = chunkOrigin;
 }
 
 QByteArray QgsLineVertexData::createVertexBuffer()
@@ -135,9 +136,9 @@ void QgsLineVertexData::addLineString( const QgsLineString &lineString, float ex
     QgsPoint p = lineString.pointN( i );
     float z = Qgs3DUtils::clampAltitude( p, altClamping, altBinding, baseHeight + extraHeightOffset, centroid, renderContext );
 
-    vertices << QVector3D( static_cast< float >( p.x() - renderContext.origin().x() ),
+    vertices << QVector3D( static_cast< float >( p.x() - origin.x() ),
                            z,
-                           static_cast< float >( -( p.y() - renderContext.origin().y() ) ) );
+                           static_cast< float >( -( p.y() - origin.y() ) ) );
     indexes << vertices.count() - 1;
   }
 
@@ -168,13 +169,13 @@ void QgsLineVertexData::addVerticalLines( const QgsLineString &lineString, float
     if ( withAdjacency )
       indexes << vertices.count();  // add the following vertex (for adjacency)
 
-    vertices << QVector3D( static_cast< float >( p.x() - renderContext.origin().x() ),
+    vertices << QVector3D( static_cast< float >( p.x() - origin.x() ),
                            z,
-                           static_cast< float >( -( p.y() - renderContext.origin().y() ) ) );
+                           static_cast< float >( -( p.y() - origin.y() ) ) );
     indexes << vertices.count() - 1;
-    vertices << QVector3D( static_cast< float >( p.x() - renderContext.origin().x() ),
+    vertices << QVector3D( static_cast< float >( p.x() - origin.x() ),
                            z2,
-                           static_cast< float >( -( p.y() - renderContext.origin().y() ) ) );
+                           static_cast< float >( -( p.y() - origin.y() ) ) );
     indexes << vertices.count() - 1;
 
     if ( withAdjacency )

src/3d/symbols/qgslinevertexdata_p.h

@@ -80,11 +80,12 @@ struct QgsLineVertexData
   Qgis::AltitudeClamping altClamping = Qgis::AltitudeClamping::Relative;
   Qgis::AltitudeBinding altBinding = Qgis::AltitudeBinding::Vertex;
   float baseHeight = 0;
-  Qgs3DRenderContext renderContext;
+  Qgs3DRenderContext renderContext;  // used for altitude clamping
+  QgsVector3D origin;                // all coordinates are relative to this origin (e.g. center of the chunk)
 
   QgsLineVertexData();
 
-  void init( Qgis::AltitudeClamping clamping, Qgis::AltitudeBinding binding, float height, const Qgs3DRenderContext &renderContext );
+  void init( Qgis::AltitudeClamping clamping, Qgis::AltitudeBinding binding, float height, const Qgs3DRenderContext &renderContext, const QgsVector3D &chunkOrigin );
 
   QByteArray createVertexBuffer();
   QByteArray createIndexBuffer();