private void ComputeNativeValues(int numChannels)
{
this.nativeColorValue = new float[numChannels];
if (this.nativeColorValue.GetLength(0) > 0)
{
float[] sRGBValue = new float[3];
sRGBValue[0] = this.sRgbColor.r / 255.0f;
sRGBValue[1] = this.sRgbColor.g / 255.0f;
sRGBValue[2] = this.sRgbColor.b / 255.0f;
ColorTransform colorTransform = new ColorTransform(this.context, new ColorContext(PixelFormats.Bgra32));
colorTransform.Translate(sRGBValue, this.nativeColorValue);
}
}
///<summary>
/// private helper function to set context values from a color value with a set context and ScRgb values
///</summary>
///
private void ComputeScRgbValues()
{
if (this.context != null)
{
Color c2 = Color.FromRgb(0, 0, 0);
c2.context = new ColorContext(PixelFormats.Bgra32);
ColorTransform colorTransform = new ColorTransform(this.context, c2.context);
float[] scRGBValue = new float[3];
colorTransform.Translate(this.nativeColorValue, scRGBValue);
this.scRgbColor.r = sRgbToScRgb((byte)((255.0f * scRGBValue[0]) + 0.5f));
this.scRgbColor.g = sRgbToScRgb((byte)((255.0f * scRGBValue[1]) + 0.5f));
this.scRgbColor.b = sRgbToScRgb((byte)((255.0f * scRGBValue[2]) + 0.5f));
}
}
/// <summary>
/// Subtract operator - substracts each channel of the second color from each channel of the
/// first and returns the result
/// </summary>
/// <param name='color1'>The minuend</param>
/// <param name='color2'>The subtrahend</param>
/// <returns>Returns the unclamped differnce</returns>
public static Color operator -(Color color1, Color color2)
{
if (color1.context == null && color2.context == null)
{
Color c1 = FromScRgb(
color1.scRgbColor.a - color2.scRgbColor.a,
color1.scRgbColor.r - color2.scRgbColor.r,
color1.scRgbColor.g - color2.scRgbColor.g,
color1.scRgbColor.b - color2.scRgbColor.b
);
return(c1);
}
else if (color1.context == null || color2.context == null)
{
throw new ArgumentException(SR.Get(SRID.Color_ColorContextTypeMismatch, null));
}
else if (color1.context == color2.context)
{
Color c1 = new Color();
c1.context = color1.context;
#pragma warning suppress 6506 // c1.context is obviously not null - both color1.context AND color2.context are not null
c1.nativeColorValue = new float[c1.context.NumChannels];
for (int i = 0; i < c1.nativeColorValue.GetLength(0); i++)
{
c1.nativeColorValue[i] = color1.nativeColorValue[i] - color2.nativeColorValue[i];
}
Color c2 = Color.FromRgb(0, 0, 0);
c2.context = new ColorContext(PixelFormats.Bgra32);
ColorTransform colorTransform = new ColorTransform(c1.context, c2.context);
float[] sRGBValue = new float[3];
colorTransform.Translate(c1.nativeColorValue, sRGBValue);
if (sRGBValue[0] < 0.0f)
{
c1.sRgbColor.r = 0;
}
else if (sRGBValue[0] > 1.0f)
{
c1.sRgbColor.r = 255;
}
else
{
c1.sRgbColor.r = (byte)((sRGBValue[0] * 255.0f) + 0.5f);
}
if (sRGBValue[1] < 0.0f)
{
c1.sRgbColor.g = 0;
}
else if (sRGBValue[1] > 1.0f)
{
c1.sRgbColor.g = 255;
}
else
{
c1.sRgbColor.g = (byte)((sRGBValue[1] * 255.0f) + 0.5f);
}
if (sRGBValue[2] < 0.0f)
{
c1.sRgbColor.b = 0;
}
else if (sRGBValue[2] > 1.0f)
{
c1.sRgbColor.b = 255;
}
else
{
c1.sRgbColor.b = (byte)((sRGBValue[2] * 255.0f) + 0.5f);
}
c1.scRgbColor.r = sRgbToScRgb(c1.sRgbColor.r);
c1.scRgbColor.g = sRgbToScRgb(c1.sRgbColor.g);
c1.scRgbColor.b = sRgbToScRgb(c1.sRgbColor.b);
c1.scRgbColor.a = color1.scRgbColor.a - color2.scRgbColor.a;
if (c1.scRgbColor.a < 0.0f)
{
c1.scRgbColor.a = 0.0f;
c1.sRgbColor.a = 0;
}
else if (c1.scRgbColor.a > 1.0f)
{
c1.scRgbColor.a = 1.0f;
c1.sRgbColor.a = 255;
}
else
{
c1.sRgbColor.a = (byte)((c1.scRgbColor.a * 255.0f) + 0.5f);
}
return(c1);
}
else
{
throw new ArgumentException(SR.Get(SRID.Color_ColorContextTypeMismatch, null));
}
}
