/// <summary>Returns the average of the closest points between 'lhs' and 'rhs'.</summary>
public static v2 ClosestPoint(BRect lhs, BRect rhs)
{
v2 pt0, pt1;
ClosestPoint(lhs, rhs, out pt0, out pt1);
return((pt0 + pt1) * 0.5f);
}
/// <summary>Return the closest point on 'rect' to 'pt'</summary>
public static v2 ClosestPoint(BRect rect, v2 pt)
{
v2 lower = rect.Lower;
v2 upper = rect.Upper;
v2 closest;
if (rect.IsWithin(pt))
{
// if pt.x/pt.y > rect.sizeX/rect.sizeY then the point
// is closer to the Y edge of the rectangle
if (Math_.Abs(pt.x * rect.SizeY) > Math_.Abs(pt.y * rect.SizeX))
{
closest = new v2(pt.x, Math_.Sign(pt.y) * rect.SizeY);
}
else
{
closest = new v2(Math_.Sign(pt.x) * rect.SizeX, pt.y);
}
}
else
{
closest = new v2(
Math_.Clamp(pt.x, lower.x, upper.x),
Math_.Clamp(pt.y, lower.y, upper.y));
}
return(closest);
}
/// <summary>
/// Returns the closest points between 'lhs' and 'rhs'.
/// If 'lhs' and 'rhs' overlap, returns the points of deepest penetration.</summary>
public static void ClosestPoint(BRect lhs, BRect rhs, out v2 pt0, out v2 pt1)
{
pt0 = lhs.Centre;
pt1 = rhs.Centre;
if (rhs.Centre.x > lhs.Centre.x)
{
pt0.x += lhs.Radius.x; pt1.x += rhs.Radius.x;
}
if (rhs.Centre.x < lhs.Centre.x)
{
pt0.x -= lhs.Radius.x; pt1.x -= rhs.Radius.x;
}
if (rhs.Centre.y > lhs.Centre.y)
{
pt0.y += lhs.Radius.y; pt1.y += rhs.Radius.y;
}
if (rhs.Centre.y < lhs.Centre.y)
{
pt0.y -= lhs.Radius.y; pt1.y -= rhs.Radius.y;
}
}
/// <summary>Returns the squared distance from 'point' to 'brect'</summary>
public static float DistanceSq(v2 point, BRect brect)
{
float dist_sq = 0.0f;
v2 lower = brect.Lower;
v2 upper = brect.Upper;
if (point.x < lower.x)
{
dist_sq += Math_.Sqr(lower.x - point.x);
}
else if (point.x > upper.x)
{
dist_sq += Math_.Sqr(point.x - upper.x);
}
if (point.y < lower.y)
{
dist_sq += Math_.Sqr(lower.y - point.y);
}
else if (point.y > upper.y)
{
dist_sq += Math_.Sqr(point.y - upper.y);
}
return(dist_sq);
}
/// <summary>Returns true if 'rhs' intersects with this bounding rectangle</summary>
public static bool IsIntersection(BRect lhs, BRect rhs)
{
return
(Math.Abs(lhs.m_centre.x - rhs.m_centre.x) <= (lhs.m_radius.x + rhs.m_radius.x) &&
Math.Abs(lhs.m_centre.y - rhs.m_centre.y) <= (lhs.m_radius.y + rhs.m_radius.y));
}
/// <summary>Returns true if 'brect' is within this bounding rectangle (within 'tol'erance)</summary>
public bool IsWithin(BRect bbox, float tol = 0f)
{
return
(Math.Abs(bbox.m_centre.x - m_centre.x) <= (m_radius.x - bbox.m_radius.x + tol) &&
Math.Abs(bbox.m_centre.y - m_centre.y) <= (m_radius.y - bbox.m_radius.y + tol));
}