Draw point labels inside plot if possible

Prior to this commit, if a point was on
the perifery of a plot, the label could
be drawn off the plot.  This commit moves
the label into the viewport and keeps the
label close to the point.

libkoviz/bookview_curves.cpp

@@ -309,15 +309,22 @@ void CurvesView::_paintCurve(const QModelIndex& curveIdx,
             QTransform I;
             painter.setTransform(I);
             double top = tbox.y()-fontMetrics().ascent();
+            QPoint drawPt;
             if ( top >= 0 ) {
                 // Draw label over curve
-                painter.drawText(tbox.topLeft()-QPointF(0,5),label);
+                drawPt = tbox.topLeft().toPoint()-QPoint(0,5);
             } else {
                 // Draw label under curve since it would drawn off page
-                painter.drawText(tbox.topLeft()+
-                                 QPointF(0,fontMetrics().ascent())
-                                 +QPointF(0,5),label);
+                drawPt = tbox.topLeft().toPoint()+
+                                QPoint(0,fontMetrics().ascent()) + QPoint(0,5);
             }
+            QRect labelRect = painter.fontMetrics().boundingRect(label);
+            labelRect.moveTo(tbox.topLeft().toPoint());
+            if ( labelRect.right() > painter.viewport().right() ) {
+                // Shift label to left of point so it stays in viewport
+                drawPt = drawPt - QPoint(labelRect.width(),0);
+            }
+            painter.drawText(drawPt,label);
             painter.setTransform(Tscaled);
 
         } else if ( path->elementCount() == 0 ) {

libkoviz/layoutitem_curves.cpp

@@ -340,14 +340,21 @@ void CurvesLayoutItem::_printCoplot(const QTransform& T,
                         // It's a flatline
                         label = QString("Flatline=%1").arg(yString);
                     }
-                    int h = painter->fontMetrics().height();
                     QColor color( _bookModel->getDataString(curveIdx,
                                                         "CurveColor","Curve"));
                     QPen pen = painter->pen();
                     pen.setColor(color);
                     painter->setPen(pen);
-                    painter->drawText(
-                                     curveBBox.topLeft()-QPointF(0,h+10),label);
+
+                    int h = painter->fontMetrics().descent();
+                    QPoint drawPt = curveBBox.topLeft().toPoint()-QPoint(0,h);
+                    QRect L = painter->fontMetrics().boundingRect(label);
+                    L.moveTo(drawPt);
+                    if ( L.right() > painter->viewport().right() ) {
+                        // Move label into viewport
+                        drawPt = drawPt - QPoint(L.width(),0);
+                    }
+                    painter->drawText(drawPt,label);
                 }
             }