override public void Draw(Graphics g, DataBlock db)
{
Rectangle r = new Rectangle();
r = m_Bounds;
if (f == null)
{
f = new fft(1024);
}
if (db.m_result != DataBlock.RESULT.OK)
{
pp.X = 0;
pp.Y = 0;
g.DrawString(string.Format("Waiting for a chunk of data to analyze"), parent.Font, Brushes.White, pp);
return;
}
if (db.GetChannelLength() < f.GetNumOfSamples())
{
pp.X = 0;
pp.Y = 0;
g.DrawString(string.Format("FFT needs at least 1024 samples to work, got only {0}, try increasing the measurement time", db.GetChannelLength()), parent.Font, Brushes.White, pp);
return;
}
for (int i = 0; i < f.GetNumOfSamples(); i++)
{
f.x[i] = db.GetVoltage(0, i);
f.y[i] = 0;
}
f.FFT(0);
int maxFreq = db.m_sampleRate / 2;
int minFreq = 0;
//margin at the bottom
r.Height -= 20;
r.Width = 1024;
r.X -= (int)MinXD;
if (drawSlidingFFT)
{
DrawSlidingFFT(g, r, db);
r.Y -= 256;
DrawFFTBars(g, r);
r.Y += 256;
}
else
{
DrawFFTBars(g, r);
}
int freqStep;
for (freqStep = 500; freqStep < maxFreq; freqStep += 500)
{
int ft = lerp(0, f.GetNumOfSamples() / 2, minFreq, maxFreq, freqStep);
if (ft > 30)
{
break;
}
}
//draw legend
for (int i = 0; i < (int)maxFreq; i += freqStep)
{
int x = lerp(0, 512, minFreq, maxFreq, i);
pp.X = r.X + 2 * x;
pp.Y = r.Bottom;
g.DrawLine(Pens.Gray, pp.X, 0, pp.X, pp.Y);
g.DrawString(string.Format("{0}", i), parent.Font, Brushes.White, pp);
}
if (m_mouse != null)
{
DrawCross(g, Pens.Blue, m_mouse.X, m_mouse.Y);
pp.X = r.X;
pp.Y = r.Y + 40;
g.DrawString(string.Format("Freq: {0} Hz", ((m_mouse.X / 2) * maxFreq) / f.GetNumOfSamples() / 2), parent.Font, Brushes.White, pp);
}
}
