From: Joel Holdsworth <redacted>
Date: Wed, 24 Oct 2012 20:22:58 +0000 (+0100)
Subject: Render ruler and signals with sub-pixel accuracy
X-Git-Tag: pulseview-0.1.0~237
X-Git-Url: https://sigrok.org/gitaction?a=commitdiff_plain;h=ce6e73a8e2a2a353233b440f4bbbd53007602e1a;p=pulseview.git

Render ruler and signals with sub-pixel accuracy
---

diff --git a/pv/logicsignal.cpp b/pv/logicsignal.cpp
index 28d71d3c..a0dabe4a 100644
--- a/pv/logicsignal.cpp
+++ b/pv/logicsignal.cpp
@@ -70,8 +70,8 @@ void LogicSignal::paint(QPainter &p, const QRect &rect, double scale,
 	assert(scale > 0);
 	assert(_data);
 
-	const float high_offset = rect.top() + Margin;
-	const float low_offset = rect.bottom() - Margin;
+	const float high_offset = rect.top() + Margin + 0.5f;
+	const float low_offset = rect.bottom() - Margin + 0.5f;
 
 	const deque< shared_ptr<LogicDataSnapshot> > &snapshots =
 		_data->get_snapshots();
@@ -102,7 +102,7 @@ void LogicSignal::paint(QPainter &p, const QRect &rect, double scale,
 	for(vector<LogicDataSnapshot::EdgePair>::const_iterator i =
 			edges.begin() + 1;
 		i != edges.end() - 1; i++) {
-		const int x = (int)((*i).first / samples_per_pixel -
+		const float x = ((*i).first / samples_per_pixel -
 			pixels_offset) + rect.left();
 		*line++ = QLineF(x, high_offset, x, low_offset);
 	}
@@ -127,8 +127,8 @@ void LogicSignal::paint(QPainter &p, const QRect &rect, double scale,
 
 void LogicSignal::paint_caps(QPainter &p, QLineF *const lines,
 	vector< pair<int64_t, bool> > &edges, bool level,
-	double samples_per_pixel, double pixels_offset, int x_offset,
-	int y_offset)
+	double samples_per_pixel, double pixels_offset, float x_offset,
+	float y_offset)
 {
 	QLineF *line = lines;
 
@@ -136,9 +136,9 @@ void LogicSignal::paint_caps(QPainter &p, QLineF *const lines,
 	    i != (edges.end() - 1); i++)
 		if((*i).second == level) {
 			*line++ = QLineF(
-				(int)((*i).first / samples_per_pixel -
+				((*i).first / samples_per_pixel -
 					pixels_offset) + x_offset, y_offset,
-				(int)((*(i+1)).first / samples_per_pixel -
+				((*(i+1)).first / samples_per_pixel -
 					pixels_offset) + x_offset, y_offset);
 		}
 
diff --git a/pv/logicsignal.h b/pv/logicsignal.h
index 54145a8c..5c527206 100644
--- a/pv/logicsignal.h
+++ b/pv/logicsignal.h
@@ -61,7 +61,7 @@ private:
 	void paint_caps(QPainter &p, QLineF *const lines,
 		std::vector< std::pair<int64_t, bool> > &edges,
 		bool level, double samples_per_pixel, double pixels_offset,
-		int x_offset, int y_offset);
+		float x_offset, float y_offset);
 
 	/**
 	 * Get the colour of the logic signal
diff --git a/pv/view/ruler.cpp b/pv/view/ruler.cpp
index 5dea1947..97c0be68 100644
--- a/pv/view/ruler.cpp
+++ b/pv/view/ruler.cpp
@@ -48,6 +48,7 @@ Ruler::Ruler(View &parent) :
 void Ruler::paintEvent(QPaintEvent *event)
 {
 	QPainter p(this);
+	p.setRenderHint(QPainter::Antialiasing);
 
 	const double MinSpacing = 80;
 
@@ -101,13 +102,14 @@ void Ruler::paintEvent(QPaintEvent *event)
 			ts << (t * multiplier) << SIPrefixes[prefix] << "s";
 			p.drawText(x, 0, 0, text_height, Qt::AlignCenter |
 				Qt::AlignTop | Qt::TextDontClip, s);
-			p.drawLine(x, text_height, x, height());
+			p.drawLine(QPointF(x, text_height),
+				QPointF(x, height()));
 		}
 		else
 		{
 			// Draw a minor tick
-			p.drawLine(x, (text_height + height()) / 2,
-				x, height());
+			p.drawLine(QPointF(x, (text_height + height()) / 2),
+				QPointF(x, height()));
 		}
 
 		division++;
diff --git a/pv/view/viewport.cpp b/pv/view/viewport.cpp
index c1490fc8..99e08b27 100644
--- a/pv/view/viewport.cpp
+++ b/pv/view/viewport.cpp
@@ -61,6 +61,7 @@ void Viewport::paintEvent(QPaintEvent *event)
 		_view.session().get_signals();
 
 	QPainter p(this);
+	p.setRenderHint(QPainter::Antialiasing);
 
 	// Plot the signal
 	int offset = -_view.v_offset();