public static bool TryGetCentroidVolume(this Solid s, out CentroidVolume cv)
{
cv = null;
try
{
if (null != s &&
0 < s.Faces.Size &&
SolidUtils.IsValidForTessellation(s) &&
(null != (cv = new CentroidVolume()
{
Centroid = s.ComputeCentroid(),
Volume = s.Volume
}
)))
{
return(true);
}
}
catch (Exception e)
{
}
return(false);
}
/// <summary>
/// Calculate centroid for all non-empty solids
/// found for the given element. Family instances
/// may have their own non-empty solids, in which
/// case those are used, otherwise the symbol geometry.
/// The symbol geometry could keep track of the
/// instance transform to map it to the actual
/// project location. Instead, we ask for
/// transformed geometry to be returned, so the
/// resulting solids are already in place.
/// </summary>
public static bool TryGetCentroid(
this Element e,
Options opt,
out CentroidVolume cvol)
{
cvol = null;
GeometryElement geo = e.get_Geometry(opt);
CentroidVolume combined = new CentroidVolume();
if (null == geo)
{
return(false);
}
// List of pairs of centroid, volume for each solid
List <CentroidVolume> a
= new List <CentroidVolume>();
if (e is FamilyInstance)
{
geo = geo.GetTransformed(
Transform.Identity);
}
GeometryInstance inst = null;
foreach (GeometryObject obj in geo)
{
if (!TryGetCentroidVolume(obj as Solid, out var cv))
{
continue;
}
a.Add(cv);
inst = obj as GeometryInstance;
}
if (0 == a.Count && null != inst)
{
geo = inst.GetSymbolGeometry();
foreach (GeometryObject obj in geo)
{
if (!TryGetCentroidVolume(obj as Solid, out var cv))
{
continue;
}
a.Add(cv);
}
}
// Get the total centroid from the partial
// contributions. Each contribution is weighted
// with its associated volume, which needs to
// be factored out again at the end.
try
{
if (0 < a.Count)
{
combined = new CentroidVolume();
bool unweighted = false;
// Revit may give us volumes of 0.
// In which case we will not do a
// weighted calculation, which will
// throw a divide by zero exception.
foreach (CentroidVolume cv2 in a)
{
if (cv2.Volume == 0)
{
unweighted = true;
break;
}
}
if (unweighted)
{
foreach (var cv2 in a)
{
combined.Centroid += cv2.Centroid;
}
combined.Centroid /= a.Count;
}
else
{
foreach (var cv2 in a)
{
combined.Centroid += cv2.Volume * cv2.Centroid;
combined.Volume += cv2.Volume;
}
combined.Centroid /= (a.Count == 0 ? 1 : a.Count) * (combined.Volume == 0 ? 1 : combined.Volume);
}
}
} catch (Exception ex)
{
combined = null;
}
cvol = combined;
return(combined != null && combined != default(CentroidVolume));
}
