+
+void SigView::paintRuler(QPainter &p)
+{
+ const double MinSpacing = 20;
+
+ double tick_period = 0.0f;
+ const double min_period = _scale * MinSpacing;
+
+ double order = 10e-15;
+ while(tick_period < min_period)
+ {
+ int unit = 0;
+ while(tick_period < min_period &&
+ unit < countof(ScaleUnits))
+ tick_period = order * ScaleUnits[unit++];
+ order *= 10;
+ }
+
+ const double tick_seperation = tick_period / _scale;
+
+ p.setPen(Qt::transparent);
+ p.setBrush(QColor(0xC0, 0xC0, 0xC0));
+ p.drawRect(LabelMarginWidth, 0,
+ width() - LabelMarginWidth, RulerHeight);
+
+ p.setPen(Qt::black);
+
+ const double offset_ticks = -_offset / tick_period;
+ double x = (offset_ticks - floor(offset_ticks)) *
+ tick_seperation + LabelMarginWidth;
+ while(x < width())
+ {
+ p.drawLine(x, 0, x, RulerHeight);
+ x += tick_seperation;
+ }
+}