//HSV
/**
* Set Hue [0..1], Saturation [0..1] and Value [0..1]
*/
public void SetHSV(float hue, float saturation, float brightness, float alpha = 1.0f)
{
hue = CgMath.Saturate(hue);
saturation = CgMath.Saturate(saturation);
brightness = CgMath.Saturate(brightness);
float hseg = 6 * hue;
float c = saturation * brightness;
float x = c * (1 - Math.Abs(hseg % 2 - 1));
int i = (int)Math.Floor(hseg);
switch (i)
{
case 0: R = c; G = x; B = 0; break;
case 1: R = x; G = c; B = 0; break;
case 2: R = 0; G = c; B = x; break;
case 3: R = 0; G = x; B = c; break;
case 4: R = x; G = 0; B = c; break;
default: R = c; G = 0; B = x; break;
}
float m = brightness - c;
R += m;
G += m;
B += m;
A = alpha;
}
/**
* Returns the point on this line segment that is closest to the vector.
*/
public Vector2D SnapDelta(Vector2D v)
{
Vector2D toEnd = End - Start;
float sr = toEnd.Dot(v - Start) / toEnd.LengthSquared;
return(Start + toEnd * CgMath.Saturate(sr) - v);
}
public float DistanceSquared(LineSegment2D other)
{
//see IsIntersecting...
Vector2D v = StartToEnd;
Vector2D ov = other.StartToEnd;
Vector2D s = Start - other.Start;
float denom = v.Cross(ov);
if (denom == 0) //lines are parallel
{
float d = Direction.OrthogonalizedClockwise().Dot(s);
return(d * d);
}
float a = CgMath.Saturate(ov.Cross(s) / denom);
float b = CgMath.Saturate(v.Cross(s) / denom);
return(Math.Min(other.DistanceSquared(Sample(a)), this.DistanceSquared(other.Sample(b))));
}
