diff --git a/Canvas.cpp b/Canvas.cpp
index 3a0e0b4..28d813c 100644
--- a/Canvas.cpp
+++ b/Canvas.cpp
@@ -533,6 +533,7 @@ void Canvas::paintEvent(QPaintEvent* event)
     QPainter p(this);
     p.setRenderHint(QPainter::Antialiasing, true);
     p.translate(width() / 2.0, height() / 2.0);
+    p.scale(1.0, -1.0);
 
     p.setPen(Qt::red);
     p.drawLine(-5, 0, 5, 0);
@@ -608,7 +609,7 @@ void Canvas::leaveEvent(QEvent* event)
 void Canvas::showObjectTag(QPointF pos)
 {
     QPointF l = screenToLogical(pos);
-    Line* lineUnderCursor = findAt(l, 2.0);
+    Line* lineUnderCursor = findAt(l, 1.0);
     if (lineUnderCursor && lineUnderCursor != draggedLine) {
         QPointF p1(*lineUnderCursor->p1.x, *lineUnderCursor->p1.y);
         QPointF p2(*lineUnderCursor->p2.x, *lineUnderCursor->p2.y);
@@ -629,5 +630,7 @@ QPointF Canvas::screenToLogical(const QPointF& screenPos) const
     logical.rx() -= width() / 2.0;
     logical.ry() -= height() / 2.0;
 
+    logical.ry() = -logical.ry();
+
     return logical;
-}
+}
\ No newline at end of file