Spectrum frequency ticks MSB truncation: base algorithm

sdrbase/dsp/spectrumsettings.cpp

@@ -53,6 +53,7 @@ void SpectrumSettings::resetToDefaults()
 	m_displayMaxHold = false;
 	m_displayHistogram = false;
 	m_displayGrid = false;
+    m_truncateFreqScale = false;
 	m_averagingMode = AvgModeNone;
 	m_averagingIndex = 0;
     m_averagingValue = 1;
@@ -130,6 +131,7 @@ QByteArray SpectrumSettings::serialize() const
     s.writeS32(45, m_measurementPrecision);
     s.writeS32(46, m_measurementCenterFrequencyOffset);
     s.writeBool(47, m_findHistogramPeaks);
+    s.writeBool(58, m_truncateFreqScale);
     s.writeS32(100, m_histogramMarkers.size());
 
 	for (int i = 0; i < m_histogramMarkers.size(); i++) {
@@ -242,6 +244,7 @@ bool SpectrumSettings::deserialize(const QByteArray& data)
         d.readS32(45, &m_measurementPrecision, 1);
         d.readS32(46, &m_measurementCenterFrequencyOffset, 0);
         d.readBool(47, &m_findHistogramPeaks, false);
+        d.readBool(48, &m_truncateFreqScale, false);
 
 		int histogramMarkersSize;
 		d.readS32(100, &histogramMarkersSize, 0);

sdrbase/dsp/spectrumsettings.h

@@ -107,6 +107,7 @@ public:
 	bool m_displayCurrent;
 	bool m_displayHistogram;
 	bool m_displayGrid;
+    bool m_truncateFreqScale;
 	AveragingMode m_averagingMode;
 	int m_averagingIndex;
 	unsigned int m_averagingValue;

sdrgui/gui/glspectrum.h

@@ -63,6 +63,7 @@ public:
     void setDisplayGrid(bool display) { m_spectrum->setDisplayGrid(display); }
     void setDisplayGridIntensity(int intensity) { m_spectrum->setDisplayGridIntensity(intensity); }
     void setDisplayTraceIntensity(int intensity) { m_spectrum->setDisplayTraceIntensity(intensity); }
+    void setFreqScaleTruncationMode(bool mode) { m_spectrum->setFreqScaleTruncationMode(mode); }
     void setLinear(bool linear) { m_spectrum->setLinear(linear); }
     void setUseCalibration(bool useCalibration) { m_spectrum->setUseCalibration(useCalibration); }
     void setMeasurementParams(SpectrumSettings::Measurement measurement,

sdrgui/gui/glspectrumgui.cpp

@@ -193,6 +193,7 @@ void GLSpectrumGUI::displaySettings()
     ui->invertWaterfall->setChecked(m_settings.m_invertedWaterfall);
     ui->grid->setChecked(m_settings.m_displayGrid);
     ui->gridIntensity->setSliderPosition(m_settings.m_displayGridIntensity);
+    ui->truncateScale->setChecked(m_settings.m_truncateFreqScale);
 
     ui->decay->setToolTip(QString("Decay: %1").arg(m_settings.m_decay));
     ui->decayDivisor->setToolTip(QString("Decay divisor: %1").arg(m_settings.m_decayDivisor));
@@ -336,6 +337,7 @@ void GLSpectrumGUI::applySpectrumSettings()
     m_glSpectrum->setReferenceLevel(refLevel);
     m_glSpectrum->setPowerRange(powerRange);
     m_glSpectrum->setFPSPeriodMs(m_settings.m_fpsPeriodMs);
+    m_glSpectrum->setFreqScaleTruncationMode(m_settings.m_truncateFreqScale);
     m_glSpectrum->setLinear(m_settings.m_linear);
     m_glSpectrum->setUseCalibration(m_settings.m_useCalibration);
 
@@ -689,6 +691,13 @@ void GLSpectrumGUI::on_gridIntensity_valueChanged(int index)
     applySettings();
 }
 
+void GLSpectrumGUI::on_truncateScale_toggled(bool checked)
+{
+    m_settings.m_truncateFreqScale = checked;
+    qDebug("GLSpectrumGUI::on_truncateScale_toggled: m_truncateFreqScale: %s", (m_settings.m_truncateFreqScale ? "on" : "off"));
+    applySettings();
+}
+
 void GLSpectrumGUI::on_traceIntensity_valueChanged(int index)
 {
     m_settings.m_displayTraceIntensity = index;

sdrgui/gui/glspectrumgui.h

@@ -103,6 +103,7 @@ private slots:
     void on_spectrogramStyle_currentIndexChanged(int index);
     void on_colorMap_currentIndexChanged(int index);
 	void on_gridIntensity_valueChanged(int index);
+    void on_truncateScale_toggled(bool checked);
 	void on_traceIntensity_valueChanged(int index);
 	void on_averagingMode_currentIndexChanged(int index);
     void on_averaging_currentIndexChanged(int index);

sdrgui/gui/glspectrumgui.ui

@@ -88,6 +88,29 @@
        </property>
       </widget>
      </item>
+     <item>
+      <widget class="ButtonSwitch" name="truncateScale">
+       <property name="toolTip">
+        <string>Truncate non significant upper digits from frequency scale</string>
+       </property>
+       <property name="text">
+        <string>Grid</string>
+       </property>
+       <property name="icon">
+        <iconset resource="../resources/res.qrc">
+         <normaloff>:/truncate.png</normaloff>:/truncate.png</iconset>
+       </property>
+       <property name="iconSize">
+        <size>
+         <width>16</width>
+         <height>16</height>
+        </size>
+       </property>
+       <property name="checkable">
+        <bool>true</bool>
+       </property>
+      </widget>
+     </item>
      <item>
       <widget class="QPushButton" name="clearSpectrum">
        <property name="sizePolicy">

sdrgui/gui/glspectrumview.cpp

@@ -492,6 +492,12 @@ void GLSpectrumView::setDisplayTraceIntensity(int intensity)
     update();
 }
 
+void GLSpectrumView::setFreqScaleTruncationMode(bool mode)
+{
+    m_frequencyScale.setTruncateMode(mode);
+    update();
+}
+
 void GLSpectrumView::setLinear(bool linear)
 {
     m_mutex.lock();

sdrgui/gui/glspectrumview.h

@@ -179,6 +179,7 @@ public:
     void setDisplayGrid(bool display);
     void setDisplayGridIntensity(int intensity);
     void setDisplayTraceIntensity(int intensity);
+    void setFreqScaleTruncationMode(bool mode);
     void setLinear(bool linear);
     void setUseCalibration(bool useCalibration);
     void setMeasurements(SpectrumMeasurements *measurements) { m_measurements = measurements; }

sdrgui/gui/scaleengine.cpp

@@ -30,12 +30,18 @@ static double trunc(double d)
 
 QString ScaleEngine::formatTick(double value, int decimalPlaces)
 {
+    if (m_truncated && (m_physicalUnit != Unit::Scientific))
+    {
+        value = ((value * m_scale) - m_truncationValue) / m_scale;
+        qDebug("ScaleEngine::formatTick: value: %f decimalPlaces: %d m_scale: %f", value, decimalPlaces, m_scale);
+    }
+
 	if (m_physicalUnit != Unit::TimeHMS)
 	{
 	    if (m_physicalUnit == Unit::Scientific) {
             return QString("%1").arg(m_makeOpposite ? -value : value, 0, 'e', m_fixedDecimalPlaces);
 	    } else {
-	        return QString("%1").arg(m_makeOpposite ? -value : value, 0, 'f', decimalPlaces);
+	        return QString("%1%2").arg(m_truncated ? "'" : "").arg(m_makeOpposite ? -value : value, 0, 'f', decimalPlaces);
 	    }
 	}
 	else
@@ -49,28 +55,41 @@ QString ScaleEngine::formatTick(double value, int decimalPlaces)
 		double orig = fabs(actual);
 		double tmp;
 
-		if(orig >= 86400.0) {
+        if (m_truncated) {
+            str = "'";
+        }
+
+		if (orig >= 86400.0)
+        {
 			tmp = floor(actual / 86400.0);
-			str = QString("%1.").arg(tmp, 0, 'f', 0);
+			str += QString("%1.").arg(tmp, 0, 'f', 0);
 			actual -= tmp * 86400.0;
-			if(actual < 0.0)
+
+        	if (actual < 0.0) {
 			    actual *= -1.0;
+            }
 		}
 
-		if(orig >= 3600.0) {
+		if (orig >= 3600.0)
+        {
 			tmp = floor(actual / 3600.0);
 			str += QString("%1:").arg(tmp, 2, 'f', 0, QChar('0'));
 			actual -= tmp * 3600.0;
-			if(actual < 0.0)
+
+            if (actual < 0.0) {
 			    actual *= -1.0;
+            }
 		}
 
-		if(orig >= 60.0) {
+		if (orig >= 60.0)
+        {
 			tmp = floor(actual / 60.0);
 			str += QString("%1:").arg(tmp, 2, 'f', 0, QChar('0'));
 			actual -= tmp * 60.0;
-			if(actual < 0.0)
+
+            if (actual < 0.0) {
 			    actual *= -1.0;
+            }
 		}
 
 		tmp = m_makeOpposite ? -actual : actual;
@@ -104,8 +123,11 @@ void ScaleEngine::calcScaleFactor()
 {
 	double median, range, freqBase;
 
-	median = ((m_rangeMax - m_rangeMin) / 2.0) + m_rangeMin;
-	range = (m_rangeMax - m_rangeMin);
+    double rangeMin = m_rangeMin;
+    double rangeMax = m_rangeMax;
+
+	median = ((rangeMax - rangeMin) / 2.0) + rangeMin;
+	range = (rangeMax - rangeMin);
 	freqBase = (median == 0 ? range : median);
 	m_scale = 1.0;
 
@@ -361,8 +383,10 @@ void ScaleEngine::reCalc()
 	float lastEndPos;
 	bool done;
 
-	if(!m_recalc)
+	if (!m_recalc) {
 		return;
+    }
+
 	m_recalc = false;
 
 	m_tickList.clear();
@@ -391,6 +415,8 @@ void ScaleEngine::reCalc()
 
 	numMajorTicks = (int)((rangeMaxScaled - rangeMinScaled) / m_majorTickValueDistance);
 
+    updateTruncation(numMajorTicks);
+
 	if(numMajorTicks == 0) {
 		forceTwoTicks();
 		return;
@@ -518,13 +544,16 @@ ScaleEngine::ScaleEngine() :
     m_rangeMin(-1.0),
     m_rangeMax(1.0),
     m_recalc(true),
-    m_scale(1.0f),
+    m_scale(1.0),
 	m_majorTickValueDistance(1.0),
     m_firstMajorTickValue(1.0),
     m_numMinorTicks(1),
     m_decimalPlaces(1),
     m_fixedDecimalPlaces(2),
-    m_makeOpposite(false)
+    m_makeOpposite(false),
+    m_truncateMode(false),
+    m_truncated(false),
+    m_truncationValue(0.0)
 {
 }
 
@@ -570,7 +599,8 @@ void ScaleEngine::setRange(Unit::Physical physicalUnit, float rangeMin, float ra
 	tmpRangeMin = rangeMin;
 	tmpRangeMax = rangeMax;
 
-	if((tmpRangeMin != m_rangeMin) || (tmpRangeMax != m_rangeMax) || (m_physicalUnit != physicalUnit)) {
+	if ((tmpRangeMin != m_rangeMin) || (tmpRangeMax != m_rangeMax) || (m_physicalUnit != physicalUnit))
+    {
 		m_physicalUnit = physicalUnit;
 		m_rangeMin = tmpRangeMin;
 		m_rangeMax = tmpRangeMax;
@@ -623,3 +653,48 @@ float ScaleEngine::getScaleWidth()
 	}
 	return max;
 }
+
+void ScaleEngine::setTruncateMode(bool mode)
+{
+    qDebug("ScaleEngine::setTruncateMode: %s", (mode ? "on" : "off"));
+    m_truncateMode = mode;
+    m_recalc = true;
+    reCalc();
+}
+
+void ScaleEngine::updateTruncation(int numMajorTicks)
+{
+    m_truncated = false;
+    m_truncationValue = 0.0;
+
+    if (!m_truncateMode) {
+        return;
+    }
+
+    if (order(m_rangeMax) != order(m_rangeMin)) {
+        return;
+    }
+
+    double width = m_rangeMax - m_rangeMin;
+    int widthOrder = order(width);
+    int maxOrder = order(m_rangeMax);
+
+    if ((widthOrder < 0) || (maxOrder < 0) || (widthOrder == maxOrder)) {
+        return;
+    }
+
+    for (int i = widthOrder+1; i <= maxOrder; i++)
+    {
+        int irangeMin = floor(m_rangeMin / pow(10, i));
+        int irangeMax = floor(m_rangeMin / pow(10, i));
+
+        if (irangeMin == irangeMax)
+        {
+            m_truncated = true;
+            m_truncationValue = irangeMin * pow(10, i);
+            break;
+        }
+    }
+
+    qDebug("ScaleEngine::updateTruncation: m_truncationValue: %f", m_truncationValue);
+}

sdrgui/gui/scaleengine.h

@@ -19,6 +19,8 @@
 #ifndef INCLUDE_SCALEENGINE_H
 #define INCLUDE_SCALEENGINE_H
 
+#include <math.h>
+
 #include <QFont>
 #include <QString>
 #include <QList>
@@ -48,6 +50,7 @@ public:
     float getRangeMax() const { return m_rangeMax; }
 	void setMakeOpposite(bool makeOpposite) { m_makeOpposite = makeOpposite; }
 	void setFixedDecimalPlaces(int decimalPlaces) { m_fixedDecimalPlaces =decimalPlaces; }
+    void setTruncateMode(bool mode);
 
 	float getPosFromValue(double value);
 	float getValueFromPos(double pos);
@@ -65,10 +68,10 @@ private:
 	float m_charSize;
 
 	// graph configuration
-	float m_size;
+	double m_size;
 	Unit::Physical m_physicalUnit;
-	float m_rangeMin;
-	float m_rangeMax;
+	double m_rangeMin;
+	double m_rangeMax;
 
 	// calculated values
 	bool m_recalc;
@@ -81,6 +84,9 @@ private:
 	int m_decimalPlaces;
 	int m_fixedDecimalPlaces;
 	bool m_makeOpposite; // will show -value instead of value
+    bool m_truncateMode; //!< truncate upper digits mode
+    bool m_truncated; //!< true if upper digits are truncated
+    double m_truncationValue; //!< value to subreact from tick display values
 
 	QString formatTick(double value, int decimalPlaces);
 	void calcCharSize();
@@ -89,6 +95,11 @@ private:
 	int calcTickTextSize(double distance);
 	void forceTwoTicks();
 	void reCalc();
+    void updateTruncation(int numMajorTicks);
+
+    inline int order(double value) {
+        return floor(log10(value));
+    }
 
 	double majorTickValue(int tick);
 	double minorTickValue(int tick);

sdrgui/resources/res.qrc

@@ -1,5 +1,6 @@
 <RCC>
   <qresource prefix="/">
+    <file>truncate.png</file>
     <file>caliper.png</file>
     <file>flip_windows.png</file>
     <file>waterfall_3d.png</file>