private static Color InterpolateColor(float value, List<ThreadSafeGradientStop> stops)
{
if (value < 1 / 255f)
{
return Colors.Transparent;
}
if (stops == null || stops.Count == 0)
{
return Colors.Black;
}
if (stops.Count == 1)
{
return stops[0].Color;
}
if (stops[0].Offset >= value) //clip to bottom
{
return stops[0].Color;
}
else if (stops[stops.Count - 1].Offset <= value) //clip to top
{
return stops[stops.Count - 1].Color;
}
int i = 0;
for (i = 1; i < stops.Count; i++)
{
if (stops[i].Offset > value)
{
Color start = stops[i - 1].Color;
Color end = stops[i].Color;
double frac = (value - stops[i - 1].Offset) / (stops[i].Offset - stops[i - 1].Offset);
byte R = (byte)Math.Round((start.R * (1 - frac) + end.R * frac));
byte G = (byte)Math.Round((start.G * (1 - frac) + end.G * frac));
byte B = (byte)Math.Round((start.B * (1 - frac) + end.B * frac));
byte A = (byte)Math.Round((start.A * (1 - frac) + end.A * frac));
return Color.FromArgb(A, R, G, B);
}
}
return stops[stops.Count - 1].Color;
}
