ciao,
sono certo di aver visto anni fa uno script/comando che permetteva di ricavare a ritroso la curva di un piping dalla polisuperfice, intendo la curva che passa per il centro dei pipe, NON quella del binario che l’ha generato.
non riesco a trovarlo più….
ciao… non voglio ostinarmi, ma credo facesse (o faccia) parte di un plug-in.
Anch’io sono certo di averlo utilizzato almeno un paio di volte.
Non so dare ulteriori informazioni 
prova a vedere qui
esatto! proprio lui grazie
Ciao Marco, non so se sono la stessa cosa … io uso questo script:
import Rhino
import scriptcontext as sc
import rhinoscriptsyntax as rs
def ExtractCenterline():
go = Rhino.Input.Custom.GetObject()
go.EnablePreSelect(True, False)
go.GeometryFilter = Rhino.DocObjects.ObjectType.Surface
go.SetCommandPrompt("Select objects for centerline extraction.")
go.GetMultiple(1,0)
if go.CommandResult()!= Rhino.Commands.Result.Success:
return
objRefs = [go.Objects()[n] for n in range (go.ObjectCount)]
if not objRefs: return
curves = []
for objRef in objRefs:
pass
Face = objRef.Face()
idx = Face.FaceIndex
Id = objRef.ObjectId
test = sc.doc.Objects.Find(Id)
v = test.Geometry.Faces[idx].DuplicateFace(False)
#v.Faces.ShrinkFaces()
#sc.doc.Objects.AddBrep(v)
srf = v.Faces[0].ToNurbsSurface()
faceDomU = srf.Domain(0)
faceDomV = srf.Domain(1)
limitPt1 = srf.PointAt(faceDomU.Min,faceDomV.Min)
limitPt2 = srf.PointAt(faceDomU.Max,faceDomV.Max)
pass
# sc.doc.Objects.AddPoint(limitPt1)
# sc.doc.Objects.AddPoint(limitPt2)
parU = srf.Domain(0).Mid
parV = srf.Domain(1).Mid
UIso = srf.IsoCurve( 0, parV )
VIso = srf.IsoCurve( 1, parU )
pt = Rhino.Geometry.Surface.PointAt( srf, parU, parV )
vecNorm = Rhino.Geometry.Surface.NormalAt( srf, parU, parV )
#rs.AddLine(pt, pt + vecNorm)
UCrv = VIso.CurvatureAt(parU)
VCrv = UIso.CurvatureAt(parV)
if UCrv.Length > VCrv.Length:
section = VIso
source = UIso
UDir = True
else:
section = UIso
source = VIso
UDir = False
#sc.doc.Objects.AddCurve(section)
#sc.doc.Objects.AddCurve(source)
tol = sc.doc.ModelAbsoluteTolerance
type_rc, x = Rhino.Geometry.NurbsSurface.TryGetCone(srf,tol)
if type_rc:
print "The object appears to be a cone."
line = Rhino.Geometry.Line(x.BasePoint, x.ApexPoint)
curve = sc.doc.Objects.AddLine(line)
if curve:
sc.doc.Objects.UnselectAll()
sc.doc.Objects.Select(curve)
sc.doc.Views.Redraw()
return
else:
type_rc, x = Rhino.Geometry.NurbsSurface.TryGetCylinder(srf,tol)
if type_rc:
print "The object appears to be a cylinder."
brep = Face.DuplicateFace(False)
brep.Faces.ShrinkFaces()
tempSrf = brep.Faces[0].UnderlyingSurface()
domU = tempSrf.Domain(0)
domV = tempSrf.Domain(1)
plane = Rhino.Geometry.Plane.WorldXY
line = Rhino.Geometry.Line(x.Center, x.Center + (x.Axis))
#line = Rhino.Geometry.Line(x.Center, x.Center + (x.Axis*x.TotalHeight))
bb = tempSrf.GetBoundingBox(plane)
line.ExtendThroughBox(bb)
p1 = line.ClosestPoint(limitPt1, tol)
p2 = line.ClosestPoint(limitPt2, tol)
curve = sc.doc.Objects.AddLine(Rhino.Geometry.Line(p1,p2))
if curve:
sc.doc.Objects.UnselectAll()
sc.doc.Objects.Select(curve)
sc.doc.Views.Redraw()
return
else:
type_rc, x = Rhino.Geometry.NurbsSurface.TryGetTorus(srf,tol)
if type_rc:
print "The object appears to be a torus."
circle = Rhino.Geometry.Circle(x.Plane, x.MajorRadius)
plane = circle.Plane
brep = Face.DuplicateFace(False)
brep.Faces.ShrinkFaces()
tempSrf = brep.Faces[0].UnderlyingSurface()
domU = tempSrf.Domain(0)
domV = tempSrf.Domain(1)
p1 = plane.ClosestPoint(tempSrf.PointAt(domU[0],domV[0]))
p2 = plane.ClosestPoint(tempSrf.PointAt(domU[1],domV[1]))
p3 = circle.Center
vec1 = p3-p1
vec2 = p3-p2
arc = None
ang = Rhino.Geometry.Vector3d.VectorAngle(vec1, vec2)
if ang > .001:
arc = Rhino.Geometry.Arc(circle, ang)
if arc:
curve = sc.doc.Objects.AddArc(arc)
else:
curve = sc.doc.Objects.AddCircle(circle)
if curve:
sc.doc.Objects.UnselectAll()
sc.doc.Objects.Select(curve)
sc.doc.Views.Redraw()
return
else:
type_rc, x = Rhino.Geometry.NurbsSurface.TryGetSphere(srf,tol)
if type_rc:
print "The object appears to be a sphere."
Center_pt = sc.doc.Objects.AddPoint(x.Center)
if Center_pt:
sc.doc.Objects.UnselectAll()
sc.doc.Objects.Select(Center_pt)
sc.doc.Views.Redraw()
return
rc, circle = Rhino.Geometry.Curve.TryGetArc( section, .001 )
if rc:
nCirc = circle.ToNurbsCurve()
vecTest = Rhino.Geometry.Vector3d( circle.Center - pt )
p2 = nCirc.PointAt( nCirc.Domain.Min)
parIso = srf.ClosestPoint(p2)
if UDir:
iso2 = srf.IsoCurve( 0, parIso[2] )
else:
iso2 = srf.IsoCurve( 1, parIso[1] )
lType = Rhino.Geometry.LoftType.Straight
uPt = Rhino.Geometry.Point3d.Unset
loft = Rhino.Geometry.Brep.CreateFromLoft([source,iso2], uPt, uPt, lType, False)
lSrf = loft[0].Faces[0].UnderlyingSurface()
Curve = lSrf.IsoCurve( 1, lSrf.Domain(0).Mid )
if Curve:
curves.append(sc.doc.Objects.AddCurve(Curve))
rs.UnselectAllObjects()
rs.SelectObjects(curves)
sc.doc.Views.Redraw()
#if( __name__ == "__main__" )
ExtractCenterline()
ciao Gambler, si esatto! è priprio lo script che avevo usato e che ho anche ritrovato ieri sera
l’avevo anche inserito in un tasto editato che poi non usando se non raramente non trovavo più….
grazie