C++ QgsSymbolRenderContext::setOriginalValueVariable方法代码示例

QRectF QgsEllipseSymbolLayer::bounds( QPointF point, QgsSymbolRenderContext &context )
{
  QSizeF size = calculateSize( context );

  bool hasDataDefinedRotation = false;
  QPointF offset;
  double angle = 0;
  calculateOffsetAndRotation( context, size.width(), size.height(), hasDataDefinedRotation, offset, angle );

  QMatrix transform;

  // move to the desired position
  transform.translate( point.x() + offset.x(), point.y() + offset.y() );

  if ( !qgsDoubleNear( angle, 0.0 ) )
    transform.rotate( angle );

  double penWidth = 0.0;
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyStrokeWidth ) )
  {
    context.setOriginalValueVariable( mStrokeWidth );
    QVariant exprVal = mDataDefinedProperties.value( QgsSymbolLayer::PropertyStrokeWidth, context.renderContext().expressionContext() );

    if ( exprVal.isValid() )
    {
      bool ok;
      double strokeWidth = exprVal.toDouble( &ok );
      if ( ok )
      {
        penWidth = context.renderContext().convertToPainterUnits( strokeWidth, mStrokeWidthUnit, mStrokeWidthMapUnitScale );
      }
    }
  }
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyStrokeStyle ) )
  {
    context.setOriginalValueVariable( QgsSymbolLayerUtils::encodePenStyle( mStrokeStyle ) );
    QVariant exprVal = mDataDefinedProperties.value( QgsSymbolLayer::PropertyStrokeStyle, context.renderContext().expressionContext() );
    if ( exprVal.isValid() && exprVal.toString() == QLatin1String( "no" ) )
    {
      penWidth = 0.0;
    }
  }

  //antialiasing, add 1 pixel
  penWidth += 1;

  QRectF symbolBounds = transform.mapRect( QRectF( -size.width() / 2.0,
                        -size.height() / 2.0,
                        size.width(),
                        size.height() ) );

  //extend bounds by pen width / 2.0
  symbolBounds.adjust( -penWidth / 2.0, -penWidth / 2.0,
                       penWidth / 2.0, penWidth / 2.0 );

  return symbolBounds;
}

void QgsMarkerSymbolLayer::markerOffset( QgsSymbolRenderContext& context, double width, double height,
    QgsUnitTypes::RenderUnit widthUnit, QgsUnitTypes::RenderUnit heightUnit,
    double& offsetX, double& offsetY, const QgsMapUnitScale& widthMapUnitScale, const QgsMapUnitScale& heightMapUnitScale ) const
{
  offsetX = mOffset.x();
  offsetY = mOffset.y();

  if ( hasDataDefinedProperty( QgsSymbolLayer::EXPR_OFFSET ) )
  {
    context.setOriginalValueVariable( QgsSymbolLayerUtils::encodePoint( mOffset ) );
    QPointF offset = QgsSymbolLayerUtils::decodePoint( evaluateDataDefinedProperty( QgsSymbolLayer::EXPR_OFFSET, context ).toString() );
    offsetX = offset.x();
    offsetY = offset.y();
  }

  offsetX = QgsSymbolLayerUtils::convertToPainterUnits( context.renderContext(), offsetX, mOffsetUnit, mOffsetMapUnitScale );
  offsetY = QgsSymbolLayerUtils::convertToPainterUnits( context.renderContext(), offsetY, mOffsetUnit, mOffsetMapUnitScale );

  HorizontalAnchorPoint horizontalAnchorPoint = mHorizontalAnchorPoint;
  VerticalAnchorPoint verticalAnchorPoint = mVerticalAnchorPoint;
  if ( hasDataDefinedProperty( QgsSymbolLayer::EXPR_HORIZONTAL_ANCHOR_POINT ) )
  {
    horizontalAnchorPoint = decodeHorizontalAnchorPoint( evaluateDataDefinedProperty( QgsSymbolLayer::EXPR_HORIZONTAL_ANCHOR_POINT , context ).toString() );
  }
  if ( hasDataDefinedProperty( QgsSymbolLayer::EXPR_VERTICAL_ANCHOR_POINT ) )
  {
    verticalAnchorPoint = decodeVerticalAnchorPoint( evaluateDataDefinedProperty( QgsSymbolLayer::EXPR_VERTICAL_ANCHOR_POINT, context ).toString() );
  }

  //correct horizontal position according to anchor point
  if ( horizontalAnchorPoint == HCenter && verticalAnchorPoint == VCenter )
  {
    return;
  }

  double anchorPointCorrectionX = QgsSymbolLayerUtils::convertToPainterUnits( context.renderContext(), width, widthUnit, widthMapUnitScale ) / 2.0;
  double anchorPointCorrectionY = QgsSymbolLayerUtils::convertToPainterUnits( context.renderContext(), height, heightUnit, heightMapUnitScale ) / 2.0;
  if ( horizontalAnchorPoint == Left )
  {
    offsetX += anchorPointCorrectionX;
  }
  else if ( horizontalAnchorPoint == Right )
  {
    offsetX -= anchorPointCorrectionX;
  }

  //correct vertical position according to anchor point
  if ( verticalAnchorPoint == Top )
  {
    offsetY += anchorPointCorrectionY;
  }
  else if ( verticalAnchorPoint == Bottom )
  {
    offsetY -= anchorPointCorrectionY;
  }
}

QSizeF QgsEllipseSymbolLayer::calculateSize( QgsSymbolRenderContext &context, double *scaledWidth, double *scaledHeight )
{
  double width = 0;

  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyWidth ) ) //1. priority: data defined setting on symbol layer le
  {
    context.setOriginalValueVariable( mSymbolWidth );
    width = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyWidth, context.renderContext().expressionContext(), mSymbolWidth );
  }
  else //2. priority: global width setting
  {
    width = mSymbolWidth;
  }
  if ( scaledWidth )
  {
    *scaledWidth = width;
  }
  width = context.renderContext().convertToPainterUnits( width, mSymbolWidthUnit, mSymbolHeightMapUnitScale );

  double height = 0;
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyHeight ) ) //1. priority: data defined setting on symbol layer level
  {
    context.setOriginalValueVariable( mSymbolHeight );
    height = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyHeight, context.renderContext().expressionContext(), mSymbolHeight );
  }
  else //2. priority: global height setting
  {
    height = mSymbolHeight;
  }
  if ( scaledHeight )
  {
    *scaledHeight = height;
  }
  height = context.renderContext().convertToPainterUnits( height, mSymbolHeightUnit, mSymbolHeightMapUnitScale );
  return QSizeF( width, height );
}

void QgsEllipseSymbolLayer::calculateOffsetAndRotation( QgsSymbolRenderContext &context,
    double scaledWidth,
    double scaledHeight,
    bool &hasDataDefinedRotation,
    QPointF &offset,
    double &angle ) const
{
  double offsetX = 0;
  double offsetY = 0;
  markerOffset( context, scaledWidth, scaledHeight, mSymbolWidthUnit, mSymbolHeightUnit, offsetX, offsetY, mSymbolWidthMapUnitScale, mSymbolHeightMapUnitScale );
  offset = QPointF( offsetX, offsetY );

//priority for rotation: 1. data defined symbol level, 2. symbol layer rotation (mAngle)
  bool ok = true;
  angle = mAngle + mLineAngle;
  bool usingDataDefinedRotation = false;
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyAngle ) )
  {
    context.setOriginalValueVariable( angle );
    angle = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyAngle, context.renderContext().expressionContext(), 0 ) + mLineAngle;
    usingDataDefinedRotation = ok;
  }

  hasDataDefinedRotation = context.renderHints() & QgsSymbol::DynamicRotation || usingDataDefinedRotation;
  if ( hasDataDefinedRotation )
  {
    // For non-point markers, "dataDefinedRotation" means following the
    // shape (shape-data defined). For them, "field-data defined" does
    // not work at all. TODO: if "field-data defined" ever gets implemented
    // we'll need a way to distinguish here between the two, possibly
    // using another flag in renderHints()
    const QgsFeature *f = context.feature();
    if ( f )
    {
      const QgsGeometry g = f->geometry();
      if ( !g.isNull() && g.type() == QgsWkbTypes::PointGeometry )
      {
        const QgsMapToPixel &m2p = context.renderContext().mapToPixel();
        angle += m2p.mapRotation();
      }
    }
  }

  if ( angle )
    offset = _rotatedOffset( offset, angle );
}

void QgsMarkerSymbolLayer::markerOffset( QgsSymbolRenderContext &context, double width, double height,
    QgsUnitTypes::RenderUnit widthUnit, QgsUnitTypes::RenderUnit heightUnit,
    double &offsetX, double &offsetY, const QgsMapUnitScale &widthMapUnitScale, const QgsMapUnitScale &heightMapUnitScale ) const
{
  offsetX = mOffset.x();
  offsetY = mOffset.y();

  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyOffset ) )
  {
    context.setOriginalValueVariable( QgsSymbolLayerUtils::encodePoint( mOffset ) );
    QVariant exprVal = mDataDefinedProperties.value( QgsSymbolLayer::PropertyOffset, context.renderContext().expressionContext() );
    if ( exprVal.isValid() )
    {
      QPointF offset = QgsSymbolLayerUtils::decodePoint( exprVal.toString() );
      offsetX = offset.x();
      offsetY = offset.y();
    }
  }

  offsetX = context.renderContext().convertToPainterUnits( offsetX, mOffsetUnit, mOffsetMapUnitScale );
  offsetY = context.renderContext().convertToPainterUnits( offsetY, mOffsetUnit, mOffsetMapUnitScale );

  HorizontalAnchorPoint horizontalAnchorPoint = mHorizontalAnchorPoint;
  VerticalAnchorPoint verticalAnchorPoint = mVerticalAnchorPoint;
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyHorizontalAnchor ) )
  {
    QVariant exprVal = mDataDefinedProperties.value( QgsSymbolLayer::PropertyHorizontalAnchor, context.renderContext().expressionContext() );
    if ( exprVal.isValid() )
    {
      horizontalAnchorPoint = decodeHorizontalAnchorPoint( exprVal.toString() );
    }
  }
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyVerticalAnchor ) )
  {
    QVariant exprVal = mDataDefinedProperties.value( QgsSymbolLayer::PropertyVerticalAnchor, context.renderContext().expressionContext() );
    if ( exprVal.isValid() )
    {
      verticalAnchorPoint = decodeVerticalAnchorPoint( exprVal.toString() );
    }
  }

  //correct horizontal position according to anchor point
  if ( horizontalAnchorPoint == HCenter && verticalAnchorPoint == VCenter )
  {
    return;
  }

  double anchorPointCorrectionX = context.renderContext().convertToPainterUnits( width, widthUnit, widthMapUnitScale ) / 2.0;
  double anchorPointCorrectionY = context.renderContext().convertToPainterUnits( height, heightUnit, heightMapUnitScale ) / 2.0;
  if ( horizontalAnchorPoint == Left )
  {
    offsetX += anchorPointCorrectionX;
  }
  else if ( horizontalAnchorPoint == Right )
  {
    offsetX -= anchorPointCorrectionX;
  }

  //correct vertical position according to anchor point
  if ( verticalAnchorPoint == Top )
  {
    offsetY += anchorPointCorrectionY;
  }
  else if ( verticalAnchorPoint == Bottom )
  {
    offsetY -= anchorPointCorrectionY;
  }
}

bool QgsEllipseSymbolLayer::writeDxf( QgsDxfExport &e, double mmMapUnitScaleFactor, const QString &layerName, QgsSymbolRenderContext &context, QPointF shift ) const
{
  //width
  double symbolWidth = mSymbolWidth;

  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyWidth ) ) //1. priority: data defined setting on symbol layer le
  {
    context.setOriginalValueVariable( mSymbolWidth );
    symbolWidth = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyWidth, context.renderContext().expressionContext(), mSymbolWidth );
  }
  if ( mSymbolWidthUnit == QgsUnitTypes::RenderMillimeters )
  {
    symbolWidth *= mmMapUnitScaleFactor;
  }

  //height
  double symbolHeight = mSymbolHeight;
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyHeight ) ) //1. priority: data defined setting on symbol layer level
  {
    context.setOriginalValueVariable( mSymbolHeight );
    symbolWidth = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyHeight, context.renderContext().expressionContext(), mSymbolHeight );
  }
  if ( mSymbolHeightUnit == QgsUnitTypes::RenderMillimeters )
  {
    symbolHeight *= mmMapUnitScaleFactor;
  }

  //stroke width
  double strokeWidth = mStrokeWidth;

  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyStrokeWidth ) )
  {
    context.setOriginalValueVariable( mStrokeWidth );
    strokeWidth = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyStrokeWidth, context.renderContext().expressionContext(), mStrokeWidth );
  }
  if ( mStrokeWidthUnit == QgsUnitTypes::RenderMillimeters )
  {
    strokeWidth *= strokeWidth;
  }

  //fill color
  QColor fc = mColor;
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyFillColor ) )
  {
    context.setOriginalValueVariable( QgsSymbolLayerUtils::encodeColor( mColor ) );
    fc = mDataDefinedProperties.valueAsColor( QgsSymbolLayer::PropertyFillColor, context.renderContext().expressionContext(), mColor );
  }

  //stroke color
  QColor oc = mStrokeColor;
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyStrokeColor ) )
  {
    context.setOriginalValueVariable( QgsSymbolLayerUtils::encodeColor( mStrokeColor ) );
    oc = mDataDefinedProperties.valueAsColor( QgsSymbolLayer::PropertyStrokeColor, context.renderContext().expressionContext(), mStrokeColor );
  }

  //symbol name
  QString symbolName = mSymbolName;
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyName ) )
  {
    context.setOriginalValueVariable( mSymbolName );
    symbolName = mDataDefinedProperties.valueAsString( QgsSymbolLayer::PropertyName, context.renderContext().expressionContext(), mSymbolName );
  }

  //offset
  double offsetX = 0;
  double offsetY = 0;
  markerOffset( context, offsetX, offsetY );
  QPointF off( offsetX, offsetY );

  //priority for rotation: 1. data defined symbol level, 2. symbol layer rotation (mAngle)
  double rotation = 0.0;
  if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyAngle ) )
  {
    context.setOriginalValueVariable( mAngle );
    rotation = mDataDefinedProperties.valueAsDouble( QgsSymbolLayer::PropertyAngle, context.renderContext().expressionContext(), mAngle ) + mLineAngle;
  }
  else if ( !qgsDoubleNear( mAngle + mLineAngle, 0.0 ) )
  {
    rotation = mAngle + mLineAngle;
  }
  rotation = -rotation; //rotation in Qt is counterclockwise
  if ( rotation )
    off = _rotatedOffset( off, rotation );

  QTransform t;
  t.translate( shift.x() + offsetX, shift.y() + offsetY );

  if ( !qgsDoubleNear( rotation, 0.0 ) )
    t.rotate( rotation );

  double halfWidth = symbolWidth / 2.0;
  double halfHeight = symbolHeight / 2.0;

  if ( symbolName == QLatin1String( "circle" ) )
  {
    if ( qgsDoubleNear( halfWidth, halfHeight ) )
    {
      QgsPoint pt( t.map( QPointF( 0, 0 ) ) );
      e.writeFilledCircle( layerName, oc, pt, halfWidth );
//.........这里部分代码省略.........

void QgsEllipseSymbolLayer::renderPoint( QPointF point, QgsSymbolRenderContext &context )
{
  double scaledWidth = mSymbolWidth;
  double scaledHeight = mSymbolHeight;

  if ( mDataDefinedProperties.hasActiveProperties() )
  {
    bool ok;
    context.setOriginalValueVariable( mStrokeWidth );
    QVariant exprVal = mDataDefinedProperties.value( QgsSymbolLayer::PropertyStrokeWidth, context.renderContext().expressionContext() );
    if ( exprVal.isValid() )
    {
      double width = exprVal.toDouble( &ok );
      if ( ok )
      {
        width = context.renderContext().convertToPainterUnits( width, mStrokeWidthUnit, mStrokeWidthMapUnitScale );
        mPen.setWidthF( width );
      }
    }

    context.setOriginalValueVariable( QgsSymbolLayerUtils::encodePenStyle( mStrokeStyle ) );
    exprVal = mDataDefinedProperties.value( QgsSymbolLayer::PropertyStrokeStyle, context.renderContext().expressionContext() );
    if ( exprVal.isValid() )
    {
      mPen.setStyle( QgsSymbolLayerUtils::decodePenStyle( exprVal.toString() ) );
    }

    context.setOriginalValueVariable( QgsSymbolLayerUtils::encodePenJoinStyle( mPenJoinStyle ) );
    exprVal = mDataDefinedProperties.value( QgsSymbolLayer::PropertyJoinStyle, context.renderContext().expressionContext() );
    if ( exprVal.isValid() )
    {
      mPen.setJoinStyle( QgsSymbolLayerUtils::decodePenJoinStyle( exprVal.toString() ) );
    }

    context.setOriginalValueVariable( QgsSymbolLayerUtils::encodeColor( mColor ) );
    mBrush.setColor( mDataDefinedProperties.valueAsColor( QgsSymbolLayer::PropertyFillColor, context.renderContext().expressionContext(), mColor ) );

    context.setOriginalValueVariable( QgsSymbolLayerUtils::encodeColor( mStrokeColor ) );
    mPen.setColor( mDataDefinedProperties.valueAsColor( QgsSymbolLayer::PropertyStrokeColor, context.renderContext().expressionContext(), mStrokeColor ) );

    if ( mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyWidth ) || mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyHeight ) || mDataDefinedProperties.isActive( QgsSymbolLayer::PropertyName ) )
    {
      QString symbolName = mSymbolName;
      context.setOriginalValueVariable( mSymbolName );
      exprVal = mDataDefinedProperties.value( QgsSymbolLayer::PropertyName, context.renderContext().expressionContext() );
      if ( exprVal.isValid() )
      {
        symbolName = exprVal.toString();
      }
      preparePath( symbolName, context, &scaledWidth, &scaledHeight, context.feature() );
    }
  }

  //offset and rotation
  bool hasDataDefinedRotation = false;
  QPointF offset;
  double angle = 0;
  calculateOffsetAndRotation( context, scaledWidth, scaledHeight, hasDataDefinedRotation, offset, angle );

  QPainter *p = context.renderContext().painter();
  if ( !p )
  {
    return;
  }

  QMatrix transform;
  transform.translate( point.x() + offset.x(), point.y() + offset.y() );
  if ( !qgsDoubleNear( angle, 0.0 ) )
  {
    transform.rotate( angle );
  }

  p->setPen( mPen );
  p->setBrush( mBrush );
  p->drawPath( transform.map( mPainterPath ) );
}