public Result Execute(
ExternalCommandData commandData,
ref string message,
ElementSet elements)
{
UIApplication uiapp = commandData.Application;
UIDocument uidoc = uiapp.ActiveUIDocument;
Application app = uiapp.Application;
Document doc = uidoc.Document;
// Select all model curves in the entire model.
List<CurveElement> curves = new List<CurveElement>(
new FilteredElementCollector( doc )
.OfClass( typeof( CurveElement ) )
.ToElements()
.Cast<CurveElement>() );
int n = curves.Count;
// If there are less than two,
// there is nothing we can do.
if( 2 > n )
{
message = _prompt;
return Result.Failed;
}
// If there are exactly two, pick those.
if( 2 < n )
{
// Else, check for a pre-selection.
curves.Clear();
Selection sel = uidoc.Selection;
ICollection<ElementId> ids = sel.GetElementIds();
n = ids.Count;
Debug.Print( "{0} pre-selected elements.",
n );
// If two or more model curves were pre-
// selected, use the first two encountered.
if( 1 < n )
{
foreach( ElementId id in ids )
{
CurveElement c = doc.GetElement( id )
as CurveElement;
if( null != c )
{
curves.Add( c );
if( 2 == curves.Count )
{
Debug.Print( "Found two model curves, "
+ "ignoring everything else." );
break;
}
}
}
}
// Else, prompt for an
// interactive post-selection.
if( 2 != curves.Count )
{
curves.Clear();
ISelectionFilter f
= new JtElementsOfClassSelectionFilter<CurveElement>();
try
{
Reference r = sel.PickObject(
ObjectType.Element, f,
"Please pick first model curve." );
curves.Add( doc.GetElement( r.ElementId )
as CurveElement );
}
catch( Autodesk.Revit.Exceptions
.OperationCanceledException )
{
return Result.Cancelled;
}
try
{
Reference r = sel.PickObject(
ObjectType.Element, f,
"Please pick second model curve." );
curves.Add( doc.GetElement( r.ElementId )
as CurveElement );
}
catch( Autodesk.Revit.Exceptions
.OperationCanceledException )
{
return Result.Cancelled;
}
}
}
// Extract data from the two selected curves.
Curve c0 = curves[0].GeometryCurve;
Curve c1 = curves[1].GeometryCurve;
double sp0 = c0.GetEndParameter( 0 );
double ep0 = c0.GetEndParameter( 1 );
double step0 = ( ep0 - sp0 ) / _nSegments;
double sp1 = c1.GetEndParameter( 0 );
double ep1 = c1.GetEndParameter( 1 );
double step1 = ( ep1 - sp1 ) / _nSegments;
Debug.Print( "Two curves' step size [start, end]:"
+ " {0} [{1},{2}] -- {3} [{4},{5}]",
Util.RealString( step0 ),
Util.RealString( sp0 ),
Util.RealString( ep0 ),
Util.RealString( step1 ),
Util.RealString( sp1 ),
Util.RealString( ep1 ) );
// Modify document within a transaction.
using( Transaction tx = new Transaction( doc ) )
{
Creator creator = new Creator( doc );
tx.Start( "MidCurve" );
// Current segment start points.
double t0 = sp0;
double t1 = sp1;
XYZ p0 = c0.GetEndPoint( 0 );
XYZ p1 = c1.GetEndPoint( 0 );
XYZ p = Util.Midpoint( p0, p1 );
Debug.Assert(
p0.IsAlmostEqualTo( c0.Evaluate( t0, false ) ),
"expected equal start points" );
Debug.Assert(
p1.IsAlmostEqualTo( c1.Evaluate( t1, false ) ),
"expected equal start points" );
// Current segment end points.
t0 += step0;
t1 += step1;
XYZ q0, q1, q;
Line line;
for( int i = 0; i < _nSegments; ++i, t0 += step0, t1 += step1 )
{
q0 = c0.Evaluate( t0, false );
q1 = c1.Evaluate( t1, false );
q = Util.Midpoint( q0, q1 );
Debug.Print(
"{0} {1} {2} {3}-{4} {5}-{6} {7}-{8}",
i,
Util.RealString( t0 ),
Util.RealString( t1 ),
Util.PointString( p0 ),
Util.PointString( q0 ),
Util.PointString( p1 ),
Util.PointString( q1 ),
Util.PointString( p ),
Util.PointString( q ) );
// Create approximating curve segment.
line = Line.CreateBound( p, q );
creator.CreateModelCurve( line );
p0 = q0;
p1 = q1;
p = q;
}
tx.Commit();
}
return Result.Succeeded;
}
