void QgsAnnotationItem::updateBalloon()
{
//first test if the point is in the frame. In that case we don't need a balloon.
if ( !mMapPositionFixed ||
( mOffsetFromReferencePoint.x() < 0 && ( mOffsetFromReferencePoint.x() + mFrameSize.width() ) > 0
&& mOffsetFromReferencePoint.y() < 0 && ( mOffsetFromReferencePoint.y() + mFrameSize.height() ) > 0 ) )
{
mBalloonSegment = -1;
return;
}
//edge list
QList<QLineF> segmentList;
segmentList << segment( 0 ); segmentList << segment( 1 ); segmentList << segment( 2 ); segmentList << segment( 3 );
//find closest edge / closest edge point
double minEdgeDist = DBL_MAX;
int minEdgeIndex = -1;
QLineF minEdge;
QgsPoint minEdgePoint;
QgsPoint origin( 0, 0 );
for ( int i = 0; i < 4; ++i )
{
QLineF currentSegment = segmentList.at( i );
QgsPoint currentMinDistPoint;
double currentMinDist = origin.sqrDistToSegment( currentSegment.x1(), currentSegment.y1(), currentSegment.x2(), currentSegment.y2(), currentMinDistPoint );
if ( currentMinDist < minEdgeDist )
{
minEdgeIndex = i;
minEdgePoint = currentMinDistPoint;
minEdgeDist = currentMinDist;
minEdge = currentSegment;
}
}
if ( minEdgeIndex < 0 )
{
return;
}
//make that configurable for the item
double segmentPointWidth = 10;
mBalloonSegment = minEdgeIndex;
QPointF minEdgeEnd = minEdge.p2();
mBalloonSegmentPoint1 = QPointF( minEdgePoint.x(), minEdgePoint.y() );
if ( sqrt( minEdgePoint.sqrDist( minEdgeEnd.x(), minEdgeEnd.y() ) ) < segmentPointWidth )
{
mBalloonSegmentPoint1 = pointOnLineWithDistance( minEdge.p2(), minEdge.p1(), segmentPointWidth );
}
mBalloonSegmentPoint2 = pointOnLineWithDistance( mBalloonSegmentPoint1, minEdge.p2(), 10 );
}
bool QgsGeometryUtils::segmentMidPoint( const QgsPointV2& p1, const QgsPointV2& p2, QgsPointV2& result, double radius, const QgsPointV2& mousePos )
{
QgsPointV2 midPoint(( p1.x() + p2.x() ) / 2.0, ( p1.y() + p2.y() ) / 2.0 );
double midDist = sqrt( sqrDistance2D( p1, midPoint ) );
if ( radius < midDist )
{
return false;
}
double centerMidDist = sqrt( radius * radius - midDist * midDist );
double dist = radius - centerMidDist;
double midDx = midPoint.x() - p1.x();
double midDy = midPoint.y() - p1.y();
//get the four possible midpoints
QList<QgsPointV2> possibleMidPoints;
possibleMidPoints.append( pointOnLineWithDistance( midPoint, QgsPointV2( midPoint.x() - midDy, midPoint.y() + midDx ), dist ) );
possibleMidPoints.append( pointOnLineWithDistance( midPoint, QgsPointV2( midPoint.x() - midDy, midPoint.y() + midDx ), 2 * radius - dist ) );
possibleMidPoints.append( pointOnLineWithDistance( midPoint, QgsPointV2( midPoint.x() + midDy, midPoint.y() - midDx ), dist ) );
possibleMidPoints.append( pointOnLineWithDistance( midPoint, QgsPointV2( midPoint.x() + midDy, midPoint.y() - midDx ), 2 * radius - dist ) );
//take the closest one
double minDist = std::numeric_limits<double>::max();
int minDistIndex = -1;
for ( int i = 0; i < possibleMidPoints.size(); ++i )
{
double currentDist = sqrDistance2D( mousePos, possibleMidPoints.at( i ) );
if ( currentDist < minDist )
{
minDistIndex = i;
minDist = currentDist;
}
}
if ( minDistIndex == -1 )
{
return false;
}
result = possibleMidPoints.at( minDistIndex );
return true;
}
bool QgsComposerItem::imageSizeConsideringRotation( double& width, double& height ) const
{
if ( qAbs( mRotation ) <= 0.0 ) //width and height stays the same if there is no rotation
{
return true;
}
double x1 = 0;
double y1 = 0;
double x2 = width;
double y2 = 0;
double x3 = width;
double y3 = height;
double x4 = 0;
double y4 = height;
double midX = width / 2.0;
double midY = height / 2.0;
if ( !cornerPointOnRotatedAndScaledRect( x1, y1, width, height ) )
{
return false;
}
if ( !cornerPointOnRotatedAndScaledRect( x2, y2, width, height ) )
{
return false;
}
if ( !cornerPointOnRotatedAndScaledRect( x3, y3, width, height ) )
{
return false;
}
if ( !cornerPointOnRotatedAndScaledRect( x4, y4, width, height ) )
{
return false;
}
//assume points 1 and 3 are on the rectangle boundaries. Calculate 2 and 4.
double distM1 = sqrt(( x1 - midX ) * ( x1 - midX ) + ( y1 - midY ) * ( y1 - midY ) );
QPointF p2 = pointOnLineWithDistance( QPointF( midX, midY ), QPointF( x2, y2 ), distM1 );
if ( p2.x() < width && p2.x() > 0 && p2.y() < height && p2.y() > 0 )
{
width = sqrt(( p2.x() - x1 ) * ( p2.x() - x1 ) + ( p2.y() - y1 ) * ( p2.y() - y1 ) );
height = sqrt(( x3 - p2.x() ) * ( x3 - p2.x() ) + ( y3 - p2.y() ) * ( y3 - p2.y() ) );
return true;
}
//else assume that points 2 and 4 are on the rectangle boundaries. Calculate 1 and 3
double distM2 = sqrt(( x2 - midX ) * ( x2 - midX ) + ( y2 - midY ) * ( y2 - midY ) );
QPointF p1 = pointOnLineWithDistance( QPointF( midX, midY ), QPointF( x1, y1 ), distM2 );
QPointF p3 = pointOnLineWithDistance( QPointF( midX, midY ), QPointF( x3, y3 ), distM2 );
width = sqrt(( x2 - p1.x() ) * ( x2 - p1.x() ) + ( y2 - p1.y() ) * ( y2 - p1.y() ) );
height = sqrt(( p3.x() - x2 ) * ( p3.x() - x2 ) + ( p3.y() - y2 ) * ( p3.y() - y2 ) );
return true;
#if 0
double x1 = 0;
double y1 = 0;
double x2 = width;
double y2 = 0;
double x3 = width;
double y3 = height;
if ( !cornerPointOnRotatedAndScaledRect( x1, y1, width, height ) )
{
return false;
}
if ( !cornerPointOnRotatedAndScaledRect( x2, y2, width, height ) )
{
return false;
}
if ( !cornerPointOnRotatedAndScaledRect( x3, y3, width, height ) )
{
return false;
}
width = sqrt(( x2 - x1 ) * ( x2 - x1 ) + ( y2 - y1 ) * ( y2 - y1 ) );
height = sqrt(( x3 - x2 ) * ( x3 - x2 ) + ( y3 - y2 ) * ( y3 - y2 ) );
return true;
#endif //0
}