public static XMVector RgbToHsv(XMVector rgb)
{
XMVector r = XMVector.SplatX(rgb);
XMVector g = XMVector.SplatY(rgb);
XMVector b = XMVector.SplatZ(rgb);
XMVector min = XMVector.Min(r, XMVector.Min(g, b));
XMVector v = XMVector.Max(r, XMVector.Max(g, b));
XMVector d = XMVector.Subtract(v, min);
XMVector s = XMVector3.NearEqual(v, XMGlobalConstants.Zero, XMGlobalConstants.Epsilon) ?
XMGlobalConstants.Zero :
XMVector.Divide(d, v);
if (XMVector3.Less(d, XMGlobalConstants.Epsilon))
{
// Achromatic, assume H of 0
XMVector hv = XMVector.Select(v, XMGlobalConstants.Zero, XMGlobalConstants.Select1000);
XMVector hva = XMVector.Select(rgb, hv, XMGlobalConstants.Select1110);
return(XMVector.Select(s, hva, XMGlobalConstants.Select1011));
}
else
{
XMVector h;
if (XMVector3.Equal(r, v))
{
// Red is max
h = XMVector.Divide(XMVector.Subtract(g, b), d);
if (XMVector3.Less(g, b))
{
h = XMVector.Add(h, XMGlobalConstants.Six);
}
}
else if (XMVector3.Equal(g, v))
{
// Green is max
h = XMVector.Divide(XMVector.Subtract(b, r), d);
h = XMVector.Add(h, XMGlobalConstants.Two);
}
else
{
// Blue is max
h = XMVector.Divide(XMVector.Subtract(r, g), d);
h = XMVector.Add(h, XMGlobalConstants.Four);
}
h = XMVector.Divide(h, XMGlobalConstants.Six);
XMVector hv = XMVector.Select(v, h, XMGlobalConstants.Select1000);
XMVector hva = XMVector.Select(rgb, hv, XMGlobalConstants.Select1110);
return(XMVector.Select(s, hva, XMGlobalConstants.Select1011));
}
}
private static XMVector HueToClr(XMVector p, XMVector q, XMVector h)
{
XMVector oneSixth = XMVector.FromFloat(1.0f / 6.0f, 1.0f / 6.0f, 1.0f / 6.0f, 1.0f / 6.0f);
XMVector twoThirds = XMVector.FromFloat(2.0f / 3.0f, 2.0f / 3.0f, 2.0f / 3.0f, 2.0f / 3.0f);
XMVector t = h;
if (XMVector3.Less(t, XMGlobalConstants.Zero))
{
t = XMVector.Add(t, XMGlobalConstants.One);
}
if (XMVector3.Greater(t, XMGlobalConstants.One))
{
t = XMVector.Subtract(t, XMGlobalConstants.One);
}
if (XMVector3.Less(t, oneSixth))
{
// p + (q - p) * 6 * t
XMVector t1 = XMVector.Subtract(q, p);
XMVector t2 = XMVector.Multiply(XMGlobalConstants.Six, t);
return(XMVector.MultiplyAdd(t1, t2, p));
}
if (XMVector3.Less(t, XMGlobalConstants.OneHalf))
{
return(q);
}
if (XMVector3.Less(t, twoThirds))
{
// p + (q - p) * 6 * (2/3 - t)
XMVector t1 = XMVector.Subtract(q, p);
XMVector t2 = XMVector.Multiply(XMGlobalConstants.Six, XMVector.Subtract(twoThirds, t));
return(XMVector.MultiplyAdd(t1, t2, p));
}
return(p);
}
public static XMVector HslToRgb(XMVector hsl)
{
XMVector oneThird = XMVector.FromFloat(1.0f / 3.0f, 1.0f / 3.0f, 1.0f / 3.0f, 1.0f / 3.0f);
XMVector s = XMVector.SplatY(hsl);
XMVector l = XMVector.SplatZ(hsl);
if (XMVector3.NearEqual(s, XMGlobalConstants.Zero, XMGlobalConstants.Epsilon))
{
// Achromatic
return(XMVector.Select(hsl, l, XMGlobalConstants.Select1110));
}
else
{
XMVector h = XMVector.SplatX(hsl);
XMVector q;
if (XMVector3.Less(l, XMGlobalConstants.OneHalf))
{
q = XMVector.Multiply(l, XMVector.Add(XMGlobalConstants.One, s));
}
else
{
q = XMVector.Subtract(XMVector.Add(l, s), XMVector.Multiply(l, s));
}
XMVector p = XMVector.Subtract(XMVector.Multiply(XMGlobalConstants.Two, l), q);
XMVector r = XMColor.HueToClr(p, q, XMVector.Add(h, oneThird));
XMVector g = XMColor.HueToClr(p, q, h);
XMVector b = XMColor.HueToClr(p, q, XMVector.Subtract(h, oneThird));
XMVector rg = XMVector.Select(g, r, XMGlobalConstants.Select1000);
XMVector ba = XMVector.Select(hsl, b, XMGlobalConstants.Select1110);
return(XMVector.Select(ba, rg, XMGlobalConstants.Select1100));
}
}
public static XMVector RgbToHsl(XMVector rgb)
{
XMVector r = XMVector.SplatX(rgb);
XMVector g = XMVector.SplatY(rgb);
XMVector b = XMVector.SplatZ(rgb);
XMVector min = XMVector.Min(r, XMVector.Min(g, b));
XMVector max = XMVector.Max(r, XMVector.Max(g, b));
XMVector l = XMVector.Multiply(XMVector.Add(min, max), XMGlobalConstants.OneHalf);
XMVector d = XMVector.Subtract(max, min);
XMVector la = XMVector.Select(rgb, l, XMGlobalConstants.Select1110);
if (XMVector3.Less(d, XMGlobalConstants.Epsilon))
{
// Achromatic, assume H and S of 0
return(XMVector.Select(la, XMGlobalConstants.Zero, XMGlobalConstants.Select1100));
}
else
{
XMVector s;
XMVector h;
XMVector d2 = XMVector.Add(min, max);
if (XMVector3.Greater(l, XMGlobalConstants.OneHalf))
{
// d / (2-max-min)
s = XMVector.Divide(d, XMVector.Subtract(XMGlobalConstants.Two, d2));
}
else
{
// d / (max+min)
s = XMVector.Divide(d, d2);
}
if (XMVector3.Equal(r, max))
{
// Red is max
h = XMVector.Divide(XMVector.Subtract(g, b), d);
}
else if (XMVector3.Equal(g, max))
{
// Green is max
h = XMVector.Divide(XMVector.Subtract(b, r), d);
h = XMVector.Add(h, XMGlobalConstants.Two);
}
else
{
// Blue is max
h = XMVector.Divide(XMVector.Subtract(r, g), d);
h = XMVector.Add(h, XMGlobalConstants.Four);
}
h = XMVector.Divide(h, XMGlobalConstants.Six);
if (XMVector3.Less(h, XMGlobalConstants.Zero))
{
h = XMVector.Add(h, XMGlobalConstants.One);
}
XMVector lha = XMVector.Select(la, h, XMGlobalConstants.Select1100);
return(XMVector.Select(s, lha, XMGlobalConstants.Select1011));
}
}
