private static FloatRgb Mix(FloatRgb a, FloatRgb b, double weight)
{
var output = new FloatRgb
{
R = Arithmetic.Mix(a.R, b.R, weight),
G = Arithmetic.Mix(a.G, b.G, weight),
B = Arithmetic.Mix(a.B, b.B, weight)
};
return(output);
}
private static bool PixelClash(FloatRgb a, FloatRgb b, double threshold)
{
// Only consider pair where both are on the inside or both are on the outside
var aIn = (a.R > .5f ? 1 : 0) + (a.G > .5f ? 1 : 0) + (a.B > .5f ? 1 : 0) >= 2;
var bIn = (b.R > .5f ? 1 : 0) + (b.G > .5f ? 1 : 0) + (b.B > .5f ? 1 : 0) >= 2;
if (aIn != bIn)
{
return(false);
}
// If the change is 0 <. 1 or 2 <. 3 channels and not 1 <. 1 or 2 <. 2, it is not a clash
if (a.R > .5f && a.G > .5f && a.B > .5f || a.R < .5f && a.G < .5f && a.B < .5f ||
b.R > .5f && b.G > .5f && b.B > .5f ||
b.R < .5f && b.G < .5f && b.B < .5f)
{
return(false);
}
// Find which color is which: _a, _b = the changing channels, _c = the remaining one
float aa, ab, ba, bb, ac, bc;
if (a.R > .5f != b.R > .5f && a.R < .5f != b.R < .5f)
{
aa = a.R;
ba = b.R;
if (a.G > .5f != b.G > .5f && a.G < .5f != b.G < .5f)
{
ab = a.G;
bb = b.G;
ac = a.B;
bc = b.B;
}
else if (a.B > .5f != b.B > .5f && a.B < .5f != b.B < .5f)
{
ab = a.B;
bb = b.B;
ac = a.G;
bc = b.G;
}
else
{
return(false); // this should never happen
}
}
else if (a.G > .5f != b.G > .5f && a.G < .5f != b.G < .5f &&
a.B > .5f != b.B > .5f && a.B < .5f != b.B < .5f)
{
aa = a.G;
ba = b.G;
ab = a.B;
bb = b.B;
ac = a.R;
bc = b.R;
}
else
{
return(false);
}
// Find if the channels are in fact discontinuous
return(Math.Abs(aa - ba) >= threshold &&
Math.Abs(ab - bb) >= threshold &&
Math.Abs(ac - .5f) >=
Math.Abs(bc - .5f)); // Out of the pair, only flag the pixel farther from a shape edge
}