Major speedup when moving the mouse in the profile

After looking with great care at the result of the mouse movement
on the profile, and also playing a bit with callgrind I've found
out that one thing that we were doing wrong was the way we looked at the
items in the scene, by calling scene()->items with
Qt::ItemIntersectsShape, our shapes are very complex curves
with thousends of points and we have lots of them. and it usually
doesn't matter because *most* of the time we are getting the
tooltip information from 'get_plot_details_new', so no accessing
to items was necessary.

By changing the access from Qt::ItemIntersectsShape to
Qt::IntersectsItemBoundingRect we had a speedup of almost 500x in a
section of code that's very important, and the good thing, nothing bad
happened because one of the only things that we are using this code is to
get information from the events, not the curves.

Signed-off-by: Tomaz Canabrava <tomaz.canabrava@intel.com>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/qt-ui/profile/divetooltipitem.cpp b/qt-ui/profile/divetooltipitem.cpp
index 78bdc71a1..7f7627309 100644
--- a/qt-ui/profile/divetooltipitem.cpp
+++ b/qt-ui/profile/divetooltipitem.cpp
@@ -264,7 +264,7 @@ void ToolTipItem::refresh(const QPointF &pos)
 	}
 	free_buffer(&mb);
 
-	Q_FOREACH (QGraphicsItem *item, scene()->items(pos, Qt::IntersectsItemShape
+	Q_FOREACH (QGraphicsItem *item, scene()->items(pos, Qt::IntersectsItemBoundingRect
 		,Qt::DescendingOrder, scene()->views().first()->transform())) {
 		if (!item->toolTip().isEmpty())
 			addToolTip(item->toolTip());