void QgsSymbolLayer::prepareExpressions( const QgsSymbolRenderContext &context ) { mDataDefinedProperties.prepare( context.renderContext().expressionContext() ); if ( !context.fields().isEmpty() ) { //QgsFields is implicitly shared, so it's cheap to make a copy mFields = context.fields(); } }
void QgsSymbolLayer::prepareExpressions( const QgsSymbolRenderContext& context ) { QMap< QString, QgsDataDefined* >::const_iterator it = mDataDefinedProperties.constBegin(); for ( ; it != mDataDefinedProperties.constEnd(); ++it ) { if ( it.value() ) { it.value()->prepareExpression( context.renderContext().expressionContext() ); } } if ( !context.fields().isEmpty() ) { //QgsFields is implicitly shared, so it's cheap to make a copy mFields = context.fields(); } }
void QgsVectorFieldSymbolLayer::startRender( QgsSymbolRenderContext& context ) { if ( mLineSymbol ) { mLineSymbol->startRender( context.renderContext(), context.fields() ); } QgsFields fields = context.fields(); if ( !fields.isEmpty() ) { mXIndex = fields.lookupField( mXAttribute ); mYIndex = fields.lookupField( mYAttribute ); } else { mXIndex = -1; mYIndex = -1; } }