Ruler tick legends don't partly disappear when scrolled off the ends

diff --git a/pv/views/trace/ruler.cpp b/pv/views/trace/ruler.cpp
index 0c2b6592cf3eb90f05f18a6ca95aadb2418acfb4..63d3d23fcb946536f173ee0e184aacd1084d0039 100644 (file)
--- a/pv/views/trace/ruler.cpp
+++ b/pv/views/trace/ruler.cpp
@@ -29,6 +29,8 @@
 using namespace Qt;
 
 using std::function;
+using std::max;
+using std::min;
 using std::shared_ptr;
 using std::vector;
 
@@ -159,10 +161,18 @@ void Ruler::paintEvent(QPaintEvent*)
        p.setPen(palette().color(foregroundRole()));
 
        for (const auto& tick: tick_position_cache_->major) {
-               p.drawText(tick.first, ValueMargin, 0, text_height,
+               const int leftedge = 0;
+               const int rightedge = width();
+               const int x_tick = tick.first;
+               if ((x_tick > leftedge) && (x_tick < rightedge)) {
+                       const int x_left_bound = QFontMetrics(font()).width(tick.second) / 2;
+                       const int x_right_bound = rightedge - x_left_bound;
+                       const int x_legend = min(max(x_tick, x_left_bound), x_right_bound);
+                       p.drawText(x_legend, ValueMargin, 0, text_height,
                                AlignCenter | AlignTop | TextDontClip, tick.second);
-               p.drawLine(QPointF(tick.first, major_tick_y1),
+                       p.drawLine(QPointF(x_tick, major_tick_y1),
                        QPointF(tick.first, ruler_height));
+               }
        }
 
        for (const auto& tick: tick_position_cache_->minor) {