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40
41 #include "spectrograph.h"
42 #include <QPainter>
43 #include <QMouseEvent>
44 #include <QDebug>
45 #include <QTimerEvent>
46
47 const int NullTimerId = -1;
48 const int NullIndex = -1;
49 const int BarSelectionInterval = 2000;
50
Spectrograph(QWidget * parent)51 Spectrograph::Spectrograph(QWidget *parent)
52 : QWidget(parent)
53 , m_barSelected(NullIndex)
54 , m_timerId(NullTimerId)
55 , m_lowFreq(0.0)
56 , m_highFreq(0.0)
57 {
58 setMinimumHeight(100);
59 }
60
~Spectrograph()61 Spectrograph::~Spectrograph()
62 {
63
64 }
65
setParams(int numBars,qreal lowFreq,qreal highFreq)66 void Spectrograph::setParams(int numBars, qreal lowFreq, qreal highFreq)
67 {
68 Q_ASSERT(numBars > 0);
69 Q_ASSERT(highFreq > lowFreq);
70 m_bars.resize(numBars);
71 m_lowFreq = lowFreq;
72 m_highFreq = highFreq;
73 updateBars();
74 }
75
timerEvent(QTimerEvent * event)76 void Spectrograph::timerEvent(QTimerEvent *event)
77 {
78 Q_ASSERT(event->timerId() == m_timerId);
79 Q_UNUSED(event) // suppress warnings in release builds
80 killTimer(m_timerId);
81 m_timerId = NullTimerId;
82 m_barSelected = NullIndex;
83 update();
84 }
85
paintEvent(QPaintEvent * event)86 void Spectrograph::paintEvent(QPaintEvent *event)
87 {
88 Q_UNUSED(event)
89
90 QPainter painter(this);
91 painter.fillRect(rect(), Qt::black);
92
93 const int numBars = m_bars.count();
94
95 // Highlight region of selected bar
96 if (m_barSelected != NullIndex && numBars) {
97 QRect regionRect = rect();
98 regionRect.setLeft(m_barSelected * rect().width() / numBars);
99 regionRect.setWidth(rect().width() / numBars);
100 QColor regionColor(202, 202, 64);
101 painter.setBrush(Qt::DiagCrossPattern);
102 painter.fillRect(regionRect, regionColor);
103 painter.setBrush(Qt::NoBrush);
104 }
105
106 QColor barColor(51, 204, 102);
107 QColor clipColor(255, 255, 0);
108
109 // Draw the outline
110 const QColor gridColor = barColor.darker();
111 QPen gridPen(gridColor);
112 painter.setPen(gridPen);
113 painter.drawLine(rect().topLeft(), rect().topRight());
114 painter.drawLine(rect().topRight(), rect().bottomRight());
115 painter.drawLine(rect().bottomRight(), rect().bottomLeft());
116 painter.drawLine(rect().bottomLeft(), rect().topLeft());
117
118 QVector<qreal> dashes;
119 dashes << 2 << 2;
120 gridPen.setDashPattern(dashes);
121 painter.setPen(gridPen);
122
123 // Draw vertical lines between bars
124 if (numBars) {
125 const int numHorizontalSections = numBars;
126 QLine line(rect().topLeft(), rect().bottomLeft());
127 for (int i=1; i<numHorizontalSections; ++i) {
128 line.translate(rect().width()/numHorizontalSections, 0);
129 painter.drawLine(line);
130 }
131 }
132
133 // Draw horizontal lines
134 const int numVerticalSections = 10;
135 QLine line(rect().topLeft(), rect().topRight());
136 for (int i=1; i<numVerticalSections; ++i) {
137 line.translate(0, rect().height()/numVerticalSections);
138 painter.drawLine(line);
139 }
140
141 barColor = barColor.lighter();
142 barColor.setAlphaF(0.75);
143 clipColor.setAlphaF(0.75);
144
145 // Draw the bars
146 if (numBars) {
147 // Calculate width of bars and gaps
148 const int widgetWidth = rect().width();
149 const int barPlusGapWidth = widgetWidth / numBars;
150 const int barWidth = 0.8 * barPlusGapWidth;
151 const int gapWidth = barPlusGapWidth - barWidth;
152 const int paddingWidth = widgetWidth - numBars * (barWidth + gapWidth);
153 const int leftPaddingWidth = (paddingWidth + gapWidth) / 2;
154 const int barHeight = rect().height() - 2 * gapWidth;
155
156 for (int i=0; i<numBars; ++i) {
157 const qreal value = m_bars[i].value;
158 Q_ASSERT(value >= 0.0 && value <= 1.0);
159 QRect bar = rect();
160 bar.setLeft(rect().left() + leftPaddingWidth + (i * (gapWidth + barWidth)));
161 bar.setWidth(barWidth);
162 bar.setTop(rect().top() + gapWidth + (1.0 - value) * barHeight);
163 bar.setBottom(rect().bottom() - gapWidth);
164
165 QColor color = barColor;
166 if (m_bars[i].clipped)
167 color = clipColor;
168
169 painter.fillRect(bar, color);
170 }
171 }
172 }
173
mousePressEvent(QMouseEvent * event)174 void Spectrograph::mousePressEvent(QMouseEvent *event)
175 {
176 const QPoint pos = event->pos();
177 const int index = m_bars.count() * (pos.x() - rect().left()) / rect().width();
178 selectBar(index);
179 }
180
reset()181 void Spectrograph::reset()
182 {
183 m_spectrum.reset();
184 spectrumChanged(m_spectrum);
185 }
186
spectrumChanged(const FrequencySpectrum & spectrum)187 void Spectrograph::spectrumChanged(const FrequencySpectrum &spectrum)
188 {
189 m_spectrum = spectrum;
190 updateBars();
191 }
192
barIndex(qreal frequency) const193 int Spectrograph::barIndex(qreal frequency) const
194 {
195 Q_ASSERT(frequency >= m_lowFreq && frequency < m_highFreq);
196 const qreal bandWidth = (m_highFreq - m_lowFreq) / m_bars.count();
197 const int index = (frequency - m_lowFreq) / bandWidth;
198 if(index <0 || index >= m_bars.count())
199 Q_ASSERT(false);
200 return index;
201 }
202
barRange(int index) const203 QPair<qreal, qreal> Spectrograph::barRange(int index) const
204 {
205 Q_ASSERT(index >= 0 && index < m_bars.count());
206 const qreal bandWidth = (m_highFreq - m_lowFreq) / m_bars.count();
207 return QPair<qreal, qreal>(index * bandWidth, (index+1) * bandWidth);
208 }
209
updateBars()210 void Spectrograph::updateBars()
211 {
212 m_bars.fill(Bar());
213 FrequencySpectrum::const_iterator i = m_spectrum.begin();
214 const FrequencySpectrum::const_iterator end = m_spectrum.end();
215 for ( ; i != end; ++i) {
216 const FrequencySpectrum::Element e = *i;
217 if (e.frequency >= m_lowFreq && e.frequency < m_highFreq) {
218 Bar &bar = m_bars[barIndex(e.frequency)];
219 bar.value = qMax(bar.value, e.amplitude);
220 bar.clipped |= e.clipped;
221 }
222 }
223 update();
224 }
225
selectBar(int index)226 void Spectrograph::selectBar(int index) {
227 const QPair<qreal, qreal> frequencyRange = barRange(index);
228 const QString message = QString("%1 - %2 Hz")
229 .arg(frequencyRange.first)
230 .arg(frequencyRange.second);
231 emit infoMessage(message, BarSelectionInterval);
232
233 if (NullTimerId != m_timerId)
234 killTimer(m_timerId);
235 m_timerId = startTimer(BarSelectionInterval);
236
237 m_barSelected = index;
238 update();
239 }
240
241
242