private void OnHueRingImageSizeChanged(object sender, SizeChangedEventArgs e)
{
if (hueRingImage.ActualHeight == 0 ||
hueRingImage.ActualWidth == 0)
{
return;
}
var minSize = Math.Min(hueRingImage.ActualHeight, hueRingImage.ActualWidth);
var outerRingRadius = minSize / 2;
var innerRingRadius = outerRingRadius * 2 / 3;
var triangleWidth = innerRingRadius * Math.Sqrt(3);
var triangleHeight = innerRingRadius * 3 / 2;
var wb = new WriteableBitmap((int)triangleWidth, (int)triangleHeight);
wb.RenderColorPickerSaturationLightnessTriangle();
saturationLightnessTriangleImage.Source = wb;
saturationLightnessTriangleImage.Margin = new Thickness(0, outerRingRadius - innerRingRadius, 0, outerRingRadius - innerRingRadius * 0.5);
}