void AbstractDiagram::Private::addLabel(
LabelPaintCache* cache,
const QModelIndex& index,
const CartesianDiagramDataCompressor::CachePosition* position,
const PositionPoints& points,
const Position& autoPositionPositive, const Position& autoPositionNegative,
const qreal value, qreal favoriteAngle /* = 0.0 */ )
{
CartesianDiagramDataCompressor::AggregatedDataValueAttributes allAttrs(
aggregatedAttrs( index, position ) );
QMap<QModelIndex, DataValueAttributes>::const_iterator it;
for ( it = allAttrs.constBegin(); it != allAttrs.constEnd(); ++it ) {
DataValueAttributes dva = it.value();
if ( !dva.isVisible() ) {
continue;
}
const bool isPositive = ( value >= 0.0 );
RelativePosition relPos( dva.position( isPositive ) );
relPos.setReferencePoints( points );
if ( relPos.referencePosition().isUnknown() ) {
relPos.setReferencePosition( isPositive ? autoPositionPositive : autoPositionNegative );
}
// Rotate the label position (not the label itself) if the diagram is rotated so that the defaults still work
if ( isTransposed() ) {
KChartEnums::PositionValue posValue = relPos.referencePosition().value();
if ( posValue >= KChartEnums::PositionNorthWest && posValue <= KChartEnums::PositionWest ) {
// rotate 90 degrees clockwise
posValue = static_cast< KChartEnums::PositionValue >( posValue + 2 );
if ( posValue > KChartEnums::PositionWest ) {
// wraparound
posValue = static_cast< KChartEnums::PositionValue >( posValue -
( KChartEnums::PositionWest - KChartEnums::PositionNorthWest ) );
}
relPos.setReferencePosition( Position( posValue ) );
}
}
const QPointF referencePoint = relPos.referencePoint();
if ( !diagram->coordinatePlane()->isVisiblePoint( referencePoint ) ) {
continue;
}
const qreal fontHeight = cachedFontMetrics( dva.textAttributes().
calculatedFont( plane, KChartEnums::MeasureOrientationMinimum ), diagram )->height();
// Note: When printing data value texts and padding's Measure is using automatic reference area
// detection, the font height is used as reference size for both horizontal and vertical
// padding.
QSizeF relativeMeasureSize( fontHeight, fontHeight );
if ( !dva.textAttributes().hasRotation() ) {
TextAttributes ta = dva.textAttributes();
ta.setRotation( favoriteAngle );
dva.setTextAttributes( ta );
}
// get the size of the label text using a subset of the information going into the final layout
const QString text = formatDataValueText( dva, index, value );
QTextDocument doc;
doc.setDocumentMargin( 0 );
if ( Qt::mightBeRichText( text ) ) {
doc.setHtml( text );
} else {
doc.setPlainText( text );
}
const QFont calculatedFont( dva.textAttributes()
.calculatedFont( plane, KChartEnums::MeasureOrientationMinimum ) );
doc.setDefaultFont( calculatedFont );
const QRectF plainRect = doc.documentLayout()->frameBoundingRect( doc.rootFrame() );
/**
* A few hints on how the positioning of the text frame is done:
*
* Let's assume we have a bar chart, a text for a positive value
* to be drawn, and "North" as attrs.positivePosition().
*
* The reference point (pos) is then set to the top center point
* of a bar. The offset now depends on the alignment:
*
* Top: text is centered horizontally to the bar, bottom of
* text frame starts at top of bar
*
* Bottom: text is centered horizontally to the bar, top of
* text frame starts at top of bar
*
* Center: text is centered horizontally to the bar, center
* line of text frame is same as top of bar
*
* TopLeft: right edge of text frame is horizontal center of
* bar, bottom of text frame is top of bar.
*
* ...
*
* Positive and negative value labels are treated equally, "North"
* also refers to the top of a negative bar, and *not* to the bottom.
*
*
* "NorthEast" likewise refers to the top right edge of the bar,
* "NorthWest" to the top left edge of the bar, and so on.
*
* In other words, attrs.positivePosition() always refers to a
* position of the *bar*, and relPos.alignment() always refers
* to an alignment of the text frame relative to this position.
*/
QTransform transform;
{
// move to the general area where the label should be
QPointF calcPoint = relPos.calculatedPoint( relativeMeasureSize );
transform.translate( calcPoint.x(), calcPoint.y() );
// align the text rect; find out by how many half-widths / half-heights to move.
int dx = -1;
if ( relPos.alignment() & Qt::AlignLeft ) {
dx -= 1;
} else if ( relPos.alignment() & Qt::AlignRight ) {
dx += 1;
}
int dy = -1;
if ( relPos.alignment() & Qt::AlignTop ) {
dy -= 1;
} else if ( relPos.alignment() & Qt::AlignBottom ) {
dy += 1;
}
transform.translate( qreal( dx ) * plainRect.width() * 0.5,
qreal( dy ) * plainRect.height() * 0.5 );
// rotate the text rect around its center
transform.translate( plainRect.center().x(), plainRect.center().y() );
int rotation = dva.textAttributes().rotation();
if ( !isPositive && dva.mirrorNegativeValueTextRotation() ) {
rotation *= -1;
}
transform.rotate( rotation );
transform.translate( -plainRect.center().x(), -plainRect.center().y() );
}
QPainterPath labelArea;
//labelArea.addPolygon( transform.mapToPolygon( plainRect.toRect() ) );
//labelArea.closeSubpath();
// Not doing that because QTransform has a special case for 180° that gives a different than
// usual ordering of the points in the polygon returned by mapToPolygon( const QRect & ).
// We expect a particular ordering in paintDataValueTextsAndMarkers() by using elementAt( 0 ),
// and similar things might happen elsewhere.
labelArea.addPolygon( transform.map( QPolygon( plainRect.toRect(), true ) ) );
// store the label geometry and auxiliary data
cache->paintReplay.append( LabelPaintInfo( it.key(), dva, labelArea,
referencePoint, value >= 0.0, text ) );
}
}
