public GradientColorTable(GradientStop[] gradientPoints, int resolution)
{
if (null == gradientPoints) throw new ArgumentNullException("gradientPoints");
if (resolution < 1) throw new ArgumentException("Resolution should be at least 1", "resolution");
_sampleLength = 1f / resolution;
_resolution = (float)resolution;
_values = new Color[(int)(resolution)];
FillSamples(gradientPoints);
}
/// <summary>
/// Fills the color sample values.
/// </summary>
/// <param name="gradientPoints">The gradient points.</param>
private void FillSamples(GradientStop[] gradientPoints)
{
if (gradientPoints.Length < 2) throw new ArgumentException("Gradient points array should be at least 2 poitns length", "gradientPoints");
for (int n = 0; n < gradientPoints.Length - 1; ++n) {
int fromOffset = GetSampleOffsetFromPosition(gradientPoints[n].Position), toOffset = GetSampleOffsetFromPosition(gradientPoints[n + 1].Position);
if (toOffset == fromOffset) {
_values[toOffset] = gradientPoints[n].Color;
} else {
Color color1 = gradientPoints[n].Color;
Color color2 = gradientPoints[n + 1].Color;
color2 = new Color( color2.R - color1.R, color2.G - color1.G, color2.B - color1.B, color2.A - color1.A);
//Color.Multiply(ref color2, 1f / (toOffset - fromOffset), out color2);
color2 = color2 * (1f / (toOffset - fromOffset));
//fill colors from/to offset
for (int m = fromOffset; m <= toOffset; ++m) {
_values[m] = color1;
color1 = new Color(color2.R + color1.R, color2.G + color1.G, color2.B + color1.B, color2.A + color1.A);
}
}
}
}
