TechDraw: Snap: disable snap if ALT is pressed.

src/Mod/TechDraw/Gui/QGIView.cpp

@@ -22,6 +22,7 @@
 
 #include "PreCompiled.h"
 #ifndef _PreComp_
+# include <QApplication>
 # include <QGraphicsSceneHoverEvent>
 # include <QGraphicsSceneMouseEvent>
 # include <QPainter>
@@ -178,7 +179,9 @@ QVariant QGIView::itemChange(GraphicsItemChange change, const QVariant &value)
         }
         else {
             // For general views we check if we need to snap to a position
-            snapPosition(newPos);
+            if (!(QApplication::keyboardModifiers() & Qt::AltModifier)) {
+                snapPosition(newPos);
+            }
         }
 
         // tell the feature that we have moved

src/Mod/TechDraw/Gui/QGIViewDimension.cpp

@@ -29,6 +29,7 @@
 #ifndef _PreComp_
 # include <cmath>
 
+# include <QApplication>
 # include <QGraphicsScene>
 # include <QGraphicsSceneMouseEvent>
 # include <QPaintDevice>
@@ -132,8 +133,10 @@ QVariant QGIDatumLabel::itemChange(GraphicsItemChange change, const QVariant& va
         }
     }
     else if (change == ItemPositionHasChanged && scene()) {
-        QPointF newPos = value.toPointF();    //position within parent!
-        snapPosition(newPos);
+        if (!(QApplication::keyboardModifiers() & Qt::AltModifier)) {
+            QPointF newPos = value.toPointF();    //position within parent!
+            snapPosition(newPos);
+        }
 
         setLabelCenter();
         m_dragState = Dragging;