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50
51 #include "spectrograph.h"
52 #include <QDebug>
53 #include <QMouseEvent>
54 #include <QPainter>
55 #include <QTimerEvent>
56
57 const int NullTimerId = -1;
58 const int NullIndex = -1;
59 const int BarSelectionInterval = 2000;
60
Spectrograph(QWidget * parent)61 Spectrograph::Spectrograph(QWidget *parent)
62 : QWidget(parent)
63 , m_barSelected(NullIndex)
64 , m_timerId(NullTimerId)
65 , m_lowFreq(0.0)
66 , m_highFreq(0.0)
67 {
68 setMinimumHeight(100);
69 }
70
~Spectrograph()71 Spectrograph::~Spectrograph()
72 {
73
74 }
75
setParams(int numBars,qreal lowFreq,qreal highFreq)76 void Spectrograph::setParams(int numBars, qreal lowFreq, qreal highFreq)
77 {
78 Q_ASSERT(numBars > 0);
79 Q_ASSERT(highFreq > lowFreq);
80 m_bars.resize(numBars);
81 m_lowFreq = lowFreq;
82 m_highFreq = highFreq;
83 updateBars();
84 }
85
timerEvent(QTimerEvent * event)86 void Spectrograph::timerEvent(QTimerEvent *event)
87 {
88 Q_ASSERT(event->timerId() == m_timerId);
89 Q_UNUSED(event) // suppress warnings in release builds
90 killTimer(m_timerId);
91 m_timerId = NullTimerId;
92 m_barSelected = NullIndex;
93 update();
94 }
95
paintEvent(QPaintEvent * event)96 void Spectrograph::paintEvent(QPaintEvent *event)
97 {
98 Q_UNUSED(event)
99
100 QPainter painter(this);
101 painter.fillRect(rect(), Qt::black);
102
103 const int numBars = m_bars.count();
104
105 // Highlight region of selected bar
106 if (m_barSelected != NullIndex && numBars) {
107 QRect regionRect = rect();
108 regionRect.setLeft(m_barSelected * rect().width() / numBars);
109 regionRect.setWidth(rect().width() / numBars);
110 QColor regionColor(202, 202, 64);
111 painter.setBrush(Qt::DiagCrossPattern);
112 painter.fillRect(regionRect, regionColor);
113 painter.setBrush(Qt::NoBrush);
114 }
115
116 QColor barColor(51, 204, 102);
117 QColor clipColor(255, 255, 0);
118
119 // Draw the outline
120 const QColor gridColor = barColor.darker();
121 QPen gridPen(gridColor);
122 painter.setPen(gridPen);
123 painter.drawLine(rect().topLeft(), rect().topRight());
124 painter.drawLine(rect().topRight(), rect().bottomRight());
125 painter.drawLine(rect().bottomRight(), rect().bottomLeft());
126 painter.drawLine(rect().bottomLeft(), rect().topLeft());
127
128 QVector<qreal> dashes;
129 dashes << 2 << 2;
130 gridPen.setDashPattern(dashes);
131 painter.setPen(gridPen);
132
133 // Draw vertical lines between bars
134 if (numBars) {
135 const int numHorizontalSections = numBars;
136 QLine line(rect().topLeft(), rect().bottomLeft());
137 for (int i=1; i<numHorizontalSections; ++i) {
138 line.translate(rect().width()/numHorizontalSections, 0);
139 painter.drawLine(line);
140 }
141 }
142
143 // Draw horizontal lines
144 const int numVerticalSections = 10;
145 QLine line(rect().topLeft(), rect().topRight());
146 for (int i=1; i<numVerticalSections; ++i) {
147 line.translate(0, rect().height()/numVerticalSections);
148 painter.drawLine(line);
149 }
150
151 barColor = barColor.lighter();
152 barColor.setAlphaF(0.75);
153 clipColor.setAlphaF(0.75);
154
155 // Draw the bars
156 if (numBars) {
157 // Calculate width of bars and gaps
158 const int widgetWidth = rect().width();
159 const int barPlusGapWidth = widgetWidth / numBars;
160 const int barWidth = 0.8 * barPlusGapWidth;
161 const int gapWidth = barPlusGapWidth - barWidth;
162 const int paddingWidth = widgetWidth - numBars * (barWidth + gapWidth);
163 const int leftPaddingWidth = (paddingWidth + gapWidth) / 2;
164 const int barHeight = rect().height() - 2 * gapWidth;
165
166 for (int i=0; i<numBars; ++i) {
167 const qreal value = m_bars[i].value;
168 Q_ASSERT(value >= 0.0 && value <= 1.0);
169 QRect bar = rect();
170 bar.setLeft(rect().left() + leftPaddingWidth + (i * (gapWidth + barWidth)));
171 bar.setWidth(barWidth);
172 bar.setTop(rect().top() + gapWidth + (1.0 - value) * barHeight);
173 bar.setBottom(rect().bottom() - gapWidth);
174
175 QColor color = barColor;
176 if (m_bars[i].clipped)
177 color = clipColor;
178
179 painter.fillRect(bar, color);
180 }
181 }
182 }
183
mousePressEvent(QMouseEvent * event)184 void Spectrograph::mousePressEvent(QMouseEvent *event)
185 {
186 const QPoint pos = event->pos();
187 const int index = m_bars.count() * (pos.x() - rect().left()) / rect().width();
188 selectBar(index);
189 }
190
reset()191 void Spectrograph::reset()
192 {
193 m_spectrum.reset();
194 spectrumChanged(m_spectrum);
195 }
196
spectrumChanged(const FrequencySpectrum & spectrum)197 void Spectrograph::spectrumChanged(const FrequencySpectrum &spectrum)
198 {
199 m_spectrum = spectrum;
200 updateBars();
201 }
202
barIndex(qreal frequency) const203 int Spectrograph::barIndex(qreal frequency) const
204 {
205 Q_ASSERT(frequency >= m_lowFreq && frequency < m_highFreq);
206 const qreal bandWidth = (m_highFreq - m_lowFreq) / m_bars.count();
207 const int index = (frequency - m_lowFreq) / bandWidth;
208 if (index <0 || index >= m_bars.count())
209 Q_ASSERT(false);
210 return index;
211 }
212
barRange(int index) const213 QPair<qreal, qreal> Spectrograph::barRange(int index) const
214 {
215 Q_ASSERT(index >= 0 && index < m_bars.count());
216 const qreal bandWidth = (m_highFreq - m_lowFreq) / m_bars.count();
217 return QPair<qreal, qreal>(index * bandWidth, (index+1) * bandWidth);
218 }
219
updateBars()220 void Spectrograph::updateBars()
221 {
222 m_bars.fill(Bar());
223 FrequencySpectrum::const_iterator i = m_spectrum.begin();
224 const FrequencySpectrum::const_iterator end = m_spectrum.end();
225 for ( ; i != end; ++i) {
226 const FrequencySpectrum::Element e = *i;
227 if (e.frequency >= m_lowFreq && e.frequency < m_highFreq) {
228 Bar &bar = m_bars[barIndex(e.frequency)];
229 bar.value = qMax(bar.value, e.amplitude);
230 bar.clipped |= e.clipped;
231 }
232 }
233 update();
234 }
235
selectBar(int index)236 void Spectrograph::selectBar(int index) {
237 const QPair<qreal, qreal> frequencyRange = barRange(index);
238 const QString message = QString("%1 - %2 Hz")
239 .arg(frequencyRange.first)
240 .arg(frequencyRange.second);
241 emit infoMessage(message, BarSelectionInterval);
242
243 if (NullTimerId != m_timerId)
244 killTimer(m_timerId);
245 m_timerId = startTimer(BarSelectionInterval);
246
247 m_barSelected = index;
248 update();
249 }
250
251
252