X-Git-Url: https://sigrok.org/gitweb/?a=blobdiff_plain;f=pv%2Fview%2Fruler.cpp;h=3cc2eb173404e0213c87d6161c198f2b00ad94c1;hb=18f7104f875a71bceeb152398b682737528a4ad7;hp=86f73f95e457c7306cbc51e6e55b51e4de939417;hpb=84a0d458a4b04141dd45af6dec44d36782ee163e;p=pulseview.git

diff --git a/pv/view/ruler.cpp b/pv/view/ruler.cpp
index 86f73f95..3cc2eb17 100644
--- a/pv/view/ruler.cpp
+++ b/pv/view/ruler.cpp
@@ -52,42 +52,16 @@ QSize Ruler::sizeHint() const
 
 void Ruler::paintEvent(QPaintEvent*)
 {
-	const double SpacingIncrement = 32.0f;
-	const double MinValueSpacing = 32.0f;
 	const int ValueMargin = 3;
 
 	QPainter p(this);
 	p.setRenderHint(QPainter::Antialiasing);
 
-	double min_width = SpacingIncrement, typical_width;
-	double tick_period;
-	unsigned int prefix;
-
-	// Find tick spacing, and number formatting that does not cause
-	// value to collide.
-	do
-	{
-		const double min_period = _view.scale() * min_width;
-
-		const int order = (int)floorf(log10f(min_period));
-		const double order_decimal = pow(10.0, order);
-
-		unsigned int unit = 0;
-
-		do
-		{
-			tick_period = order_decimal * ScaleUnits[unit++];
-		} while (tick_period < min_period && unit < countof(ScaleUnits));
-
-		prefix = (order - pv::util::FirstSIPrefixPower) / 3;
+	std::pair<double, unsigned int> spacing =
+		calculate_tick_spacing(p, _view.scale(), _view.offset());
 
-		typical_width = p.boundingRect(0, 0, INT_MAX, INT_MAX,
-			AlignLeft | AlignTop, pv::util::format_time(_view.offset(),
-			prefix)).width() + MinValueSpacing;
-
-		min_width += SpacingIncrement;
-
-	} while(typical_width > tick_period / _view.scale());
+	double tick_period = spacing.first;
+	unsigned int prefix = spacing.second;
 
 	const int text_height = p.boundingRect(0, 0, INT_MAX, INT_MAX,
 		AlignLeft | AlignTop, "8").height();
@@ -163,5 +137,41 @@ void Ruler::hover_point_changed()
 	update();
 }
 
+std::pair<double, unsigned int> Ruler::calculate_tick_spacing(
+	QPainter& p, double scale, double offset)
+{
+	const double SpacingIncrement = 32.0f;
+	const double MinValueSpacing = 32.0f;
+
+	double min_width = SpacingIncrement, typical_width;
+
+	double tick_period;
+	unsigned int prefix;
+
+	do {
+		const double min_period = scale * min_width;
+
+		const int order = (int)floorf(log10f(min_period));
+		const double order_decimal = pow(10.0, order);
+
+		unsigned int unit = 0;
+
+		do {
+			tick_period = order_decimal * ScaleUnits[unit++];
+		} while (tick_period < min_period && unit < countof(ScaleUnits));
+
+		prefix = (order - pv::util::FirstSIPrefixPower) / 3;
+
+		typical_width = p.boundingRect(0, 0, INT_MAX, INT_MAX,
+			AlignLeft | AlignTop, pv::util::format_time(offset,
+			prefix)).width() + MinValueSpacing;
+
+		min_width += SpacingIncrement;
+
+	} while(typical_width > tick_period / scale);
+
+	return std::make_pair(tick_period, prefix);
+}
+
 } // namespace view
 } // namespace pv