/// <summary>
/// Returns the best path distance of the given [minDeg..maxDeg] angle set.
/// If you are not sure what the inputs mean don't tinker with it.
/// It uses a Golden Search algorithm.
/// </summary>
/// <param name="deltaDeg">What the tolerance from the perfect angle is</param>
/// <exception cref="ArgumentNullException">If either <paramref name="points"/> or <paramref name="template"/> is null</exception>
private static float PathDistanceAtBestAngle(List <Vector2> points, TemplateGroup.Template template, float minDeg = -45,
float maxDeg = 45, float deltaDeg = 2)
{
if (points == null)
{
throw new ArgumentNullException("Points list cannot be null!");
}
if (template == null)
{
throw new ArgumentNullException("Template cannot be null");
}
// swap them if minDeg is larger than maxDeg
if (maxDeg < minDeg)
{
float temp = minDeg;
minDeg = maxDeg;
maxDeg = temp;
}
deltaDeg = Mathf.Abs(deltaDeg);
// The strategy is Golden Section Search(GSS), an efficient
// algorithm that finds the minimum value in a range using the
// Golden Ratio
float _x1 = goldenRatio * minDeg + (1 - goldenRatio) * maxDeg;
float _f1 = PathDistanceAtAngle(points, template, Mathf.Deg2Rad * _x1);
float _x2 = goldenRatio * maxDeg + (1 - goldenRatio) * minDeg;
float _f2 = PathDistanceAtAngle(points, template, Mathf.Deg2Rad * _x2);
while (Mathf.Abs(maxDeg - minDeg) > deltaDeg)
{
if (_f1 < _f2)
{
maxDeg = _x2;
_x2 = _x1;
_f2 = _f1;
_x1 = goldenRatio * minDeg + (1 - goldenRatio) * maxDeg;
_f1 = PathDistanceAtAngle(points, template, Mathf.Deg2Rad * _x1);
}
else
{
minDeg = _x1;
_x1 = _x2;
_f1 = _f2;
_x2 = goldenRatio * maxDeg + (1 - goldenRatio) * minDeg;
_f2 = PathDistanceAtAngle(points, template, Mathf.Deg2Rad * _x2);
}
}
return(Mathf.Min(_f1, _f2));
}
/// <summary>
/// Tha path distance of a shape and a template with the shape being at a given relative rotation
/// Points is compared to a template to find the average distance between corresponding points
/// </summary>
/// <param name="rad">Radian!!</param>
/// <exception cref="ArgumentNullException">Thrown if either shape or template is null</exception>
private static float PathDistanceAtAngle(List <Vector2> shape, TemplateGroup.Template template, float rad)
{
if (shape == null)
{
throw new ArgumentNullException("Shape cannot be null!");
}
if (template == null)
{
throw new ArgumentNullException("Tempalte cannot be null!");
}
return(PathDistance(RotateListToAngle(shape, rad), template));
}
/// <summary>
/// Tha path distance of a shape and a template.
/// Points is compared to a template to find the average distance between corresponding points
/// </summary>
/// <exception cref="ArgumentNullException">Thrown if either shape or template is null</exception>
private static float PathDistance(List <Vector2> shape, TemplateGroup.Template template)
{
if (shape == null)
{
throw new ArgumentNullException("Shape cannot be null!");
}
if (template == null)
{
throw new ArgumentNullException("Template cannot ben null!");
}
int _pointCount = Mathf.Min(template.Points.Count, shape.Count);
float _currScore = 0;
for (int p = 0; p < _pointCount; p++)
{
_currScore += Vector2.Distance(shape[p], template.Points[p]);
}
return(_currScore / _pointCount);
}
