public void DrawGraphic(Signal signal, int channelNumber)
{
double middleY = MainCanvas.Height / 2;
signal.GoToSample(channelNumber, 0);
// MODE 1
if (signal.NumberOfSamples < MainCanvas.Width * 10)
{
double stepX = MainCanvas.Width / signal.NumberOfSamples;
signal.GoToSample(channelNumber, 0);
double x = 0;
points.Clear();
for (int i = 0; i < signal.NumberOfSamples; i++)
{
int sample = signal.GetSample(channelNumber);
points.Add(new Point {
X = x, Y = middleY - sample * ratioY
});
x += stepX;
}
if (polyline == null)
{
polyline = new Polyline();
polyline.Stroke = lineStroke;
polyline.Points = points;
}
if (drawMode != 1)
{
MainCanvas.Children.Clear();
MainCanvas.Children.Add(polyline);
}
drawMode = 1;
}
// MODE 2
else
{
int horizontalPixels = (int)MainCanvas.ActualWidth;
if (verticalLines == null)
{
verticalLines = new Line[horizontalPixels];
for (int pixel = 0; pixel < horizontalPixels; pixel++)
{
verticalLines[pixel] = new Line();
verticalLines[pixel].X1 = pixel;
verticalLines[pixel].X2 = pixel;
verticalLines[pixel].Stroke = lineStroke;
}
}
if (drawMode != 2)
{
MainCanvas.Children.Clear();
foreach (Line line in verticalLines)
{
MainCanvas.Children.Add(line);
}
}
drawMode = 2;
int samplesPerPixel = (int)(signal.NumberOfSamples / MainCanvas.Width) + 1;
double sampleBatchMax = double.MinValue;
double sampleBatchMin = double.MaxValue;
for (int i = 1; i < signal.NumberOfSamples; i++)
{
if (i % samplesPerPixel == 0)
{
verticalLines[i / samplesPerPixel].Y1 = middleY - sampleBatchMax * ratioY;
verticalLines[i / samplesPerPixel].Y2 = middleY - sampleBatchMin * ratioY;
sampleBatchMax = double.MinValue;
sampleBatchMin = double.MaxValue;
}
int sample = signal.GetSample(channelNumber);
if (sample > sampleBatchMax)
{
sampleBatchMax = sample;
}
if (sample < sampleBatchMin)
{
sampleBatchMin = sample;
}
}
}
}