protected override void Render(RenderContext context)
{
lock (SyncRoot)
{
var backBuffer = context.BackBuffer;
var width = context.Width;
var height = context.Height;
var h = (double)height;
var stride = context.Stride / 4;
var palette = Palette.AsFrozen();
unsafe
{
if (PlayerService.State != PlayingState.Playing)
{
return;
}
float sampleRate;
var fft = PlayerService.FFT(out sampleRate, (int)TargetRenderWidth);
if (null == fft)
{
return;
}
var freqPerChannel = ((sampleRate / 2) / fft.Length);
var lastIndex = 21000f / freqPerChannel;
if (normalizeFft.Value)
{
fft.Normalize();
}
lastIndex = lastIndex >= fft.Length ? fft.Length - 1 : lastIndex < 0 ? 0 : lastIndex;
var step = width / lastIndex;
var buf = (int *)backBuffer;
for (var i = 0; i < lastIndex; ++i)
{
var x1 = (int)Math.Floor(i * step);
var x2 = (int)Math.Ceiling((i + 1) * step);
var y1 = height - 1;
var y2 = height - (height * fft[i]);
y2 = y2 < 0 ? 0 : y2;
y2 = y2 > height ? height : y2;
x2 = x2 > width ? width : x2;
x2 = x2 < 0 ? 0 : x2;
for (var x = x1; x < x2 && x < stride; ++x)
{
for (var y = y1; y > y2; --y)
{
var target = (y * stride) + x;
var val = palette.GetColour(1d - (y / h));
buf[target] = val;
}
}
}
}
}
}