From abad24e2d61c0c84ac8495c22d29a8a3a49ee9fa Mon Sep 17 00:00:00 2001
From: Jens Steinhauser <jens.steinhauser@gmail.com>
Date: Wed, 21 May 2014 15:02:13 +0200
Subject: [PATCH] CursorHeader: Use the same number format as the ruler.

---
 pv/view/cursorheader.cpp |  6 +++-
 pv/view/ruler.cpp        | 70 +++++++++++++++++++++++-----------------
 pv/view/ruler.h          | 12 +++++++
 3 files changed, 57 insertions(+), 31 deletions(-)

diff --git a/pv/view/cursorheader.cpp b/pv/view/cursorheader.cpp
index 861cd70f..6592acd4 100644
--- a/pv/view/cursorheader.cpp
+++ b/pv/view/cursorheader.cpp
@@ -20,6 +20,7 @@
 
 #include "cursorheader.h"
 
+#include "ruler.h"
 #include "view.h"
 
 #include <QApplication>
@@ -68,9 +69,12 @@ void CursorHeader::paintEvent(QPaintEvent*)
 	QPainter p(this);
 	p.setRenderHint(QPainter::Antialiasing);
 
+	unsigned int prefix = pv::view::Ruler::calculate_tick_spacing(
+		p, _view.scale(), _view.offset()).second;
+
 	// Draw the cursors
 	if (_view.cursors_shown()) {
-		_view.cursors().draw_markers(p, rect(), 0); //prefix);
+		_view.cursors().draw_markers(p, rect(), prefix);
 	}
 }
 
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
diff --git a/pv/view/ruler.h b/pv/view/ruler.h
index cee76c68..08a9c0e1 100644
--- a/pv/view/ruler.h
+++ b/pv/view/ruler.h
@@ -42,6 +42,18 @@ private:
 public:
 	Ruler(View &parent);
 
+	/**
+	 * Find a tick spacing and number formatting that does not cause
+	 * the values to collide.
+	 * @param p A QPainter used to determine the needed space for the values.
+	 * @param scale A pv::view::View's scale.
+	 * @param offset A pv::view::View's offset.
+	 *
+	 * @return The tick period to use in 'first' and the prefix in 'second'.
+	 */
+	static std::pair<double, unsigned int> calculate_tick_spacing(
+		QPainter& p, double scale, double offset);
+
 public:
 	QSize sizeHint() const;
 
-- 
2.30.2