/// <summary>
/// Make an interpolation from c1 to c2
/// </summary>
/// <param name="c1">The left color (interp == 0.0). Set to (59, 76, 192) for cold color</param>
/// <param name="c2">The right color (interp == 1.0). Set to (180, 4, 38) for warm color</param>
/// <param name="interp">The interpolation value between 0.0 and 1.0</param>
public void FromColorInterpolation(Color c1, Color c2, float interp)
{
MSHColor m1 = new MSHColor(c1);
MSHColor m2 = new MSHColor(c2);
FromColorInterpolation(m1, m2, interp);
}
/// <summary>
/// Copy constructor
/// </summary>
/// <param name="copy">The color to copy</param>
public MSHColor(MSHColor copy)
{
M = copy.M;
S = copy.S;
H = copy.H;
A = copy.A;
}
/// <summary>
/// Adjust the Hue
/// </summary>
/// <param name="color">The saturated color</param>
/// <param name="m">The unsaturated M component</param>
/// <returns></returns>
public static float AdjustHue(MSHColor color, float m)
{
if (color.M >= m)
{
return(color.H);
}
float hSpin = (float)(color.S * Math.Sqrt(m * m - color.M * color.M) / (color.M * Math.Sin(color.S)));
if (hSpin > -Math.PI / 3.0)
{
return(color.H + hSpin);
}
return(color.H - hSpin);
}
/// <summary>
/// Make an interpolation from m1 to m2
/// </summary>
/// <param name="m1">The left color (interp == 0.0). Set to RGB = (59, 76, 192) for cold color</param>
/// <param name="m2">The right color (interp == 1.0). Set to RGB = (180, 4, 38) for warm color</param>
/// <param name="interp">The interpolation value between 0.0 and 1.0</param>
public void FromColorInterpolation(MSHColor m1, MSHColor m2, float interp)
{
float radDiff = Math.Abs(m1.H - m2.H);
if (m1.S > 0.05 &&
m2.S > 0.05 &&
radDiff > Math.PI / 3.0f)
{
float midM = m1.M;
if (midM < m2.M)
{
midM = m2.M;
}
if (midM < 98)
{
midM = 98;
}
if (interp < 0.5f)
{
m2.M = midM;
m2.S = 0;
m2.H = 0;
interp *= 2.0f;
}
else
{
m1.M = midM;
m1.S = 0;
m1.H = 0;
interp = 2.0f * interp - 1.0f;
}
}
if (m1.S < 0.05 && m2.S > 0.05)
{
m1.H = AdjustHue(m2, m1.M);
}
else if (m1.S > 0.05 && m2.S < 0.05)
{
m2.H = AdjustHue(m1, m2.M);
}
MSHColor mid = m1 * (1.0f - interp) + m2 * (interp);
M = mid.M;
S = mid.S;
H = mid.H;
}
/// <summary>
/// Make an interpolation from c1 to c2
/// </summary>
/// <param name="c1">The left color (interp == 0.0). Set to (59, 76, 192) for cold color</param>
/// <param name="c2">The right color (interp == 1.0). Set to (180, 4, 38) for warm color</param>
/// <param name="interp">The interpolation value between 0.0 and 1.0</param>
public void FromColorInterpolation(Color c1, Color c2, float interp)
{
MSHColor m1 = new MSHColor(c1);
MSHColor m2 = new MSHColor(c2);
float radDiff = Math.Abs(m1.H - m2.H);
if (m1.S > 0.05 &&
m2.S > 0.05 &&
radDiff > Math.PI / 3.0f)
{
float midM = (float)(Math.Max(Math.Max(m1.M, m2.M), 98));
if (interp < 0.5f)
{
m2.M = midM;
m2.S = 0;
m2.H = 0;
interp *= 2.0f;
}
else
{
m1.M = midM;
m1.S = 0;
m1.H = 0;
interp = 2.0f * interp - 1.0f;
}
}
if (m1.S < 0.05 && m2.S > 0.05)
{
m1.H = AdjustHue(m2, m1.M);
}
else if (m1.S > 0.05 && m2.S < 0.05)
{
m2.H = AdjustHue(m1, m2.M);
}
MSHColor mid = m1 * (1.0f - interp) + m2 * (interp);
M = mid.M;
S = mid.S;
H = mid.H;
}
/// <summary>
/// Make a linear interpolation between two LAB Color
/// </summary>
/// <param name="c1">the first color (t=0)</param>
/// <param name="c2">the second color (t=1)</param>
/// <param name="t">the progression factor (between 0 and 1)</param>
/// <returns>The interpolated color</returns>
public static MSHColor Lerp(MSHColor c1, MSHColor c2, float t)
{
return(new MSHColor(c1 * (1.0f - t) + c2 * t));
}
