CubicBasis : Add constant basis

Author: danieldresser

include/IECore/CubicBasis.h

@@ -50,7 +50,8 @@ enum class StandardCubicBasis
 		Linear,
 		Bezier,
 		BSpline,
-		CatmullRom
+		CatmullRom,
+		Constant
 };
 
 /// Provides a basis matrix class for use in constructing cubic curves.
@@ -142,6 +143,7 @@ class IECORE_EXPORT CubicBasis
 		static const CubicBasis &bezier();
 		static const CubicBasis &bSpline();
 		static const CubicBasis &catmullRom();
+		static const CubicBasis &constant();
 
 		StandardCubicBasis standardBasis() const;
 };

include/IECore/CubicBasis.inl

@@ -64,6 +64,9 @@ CubicBasis<T>::CubicBasis( StandardCubicBasis standardBasis )
 	case StandardCubicBasis::CatmullRom:
 		*this = CubicBasis<T>::catmullRom();
 		break;
+	case StandardCubicBasis::Constant:
+		*this = CubicBasis<T>::constant();
+		break;
 	case StandardCubicBasis::Unknown:
 		throw IECore::Exception( "CubicBasis::CubicBasis - Invalid basis");
 	}
@@ -352,6 +355,21 @@ const CubicBasis<T> &CubicBasis<T>::catmullRom()
 	return m;
 }
 
+template<typename T>
+const CubicBasis<T> &CubicBasis<T>::constant()
+{
+	static CubicBasis<T> m(
+		MatrixType(
+			 0,  0,  0,  0,
+			 0,  0,  0,  0,
+			 0,  0,  0,  0,
+			 1,  0,  0,  0
+		),
+		1
+	);
+	return m;
+}
+
 template<typename T>
 StandardCubicBasis CubicBasis<T>::standardBasis() const
 {
@@ -371,6 +389,10 @@ StandardCubicBasis CubicBasis<T>::standardBasis() const
 	{
 		return StandardCubicBasis::CatmullRom;
 	}
+	else if( *this == CubicBasis<T>::constant() )
+	{
+		return StandardCubicBasis::Constant;
+	}
 
 	return StandardCubicBasis::Unknown;
 }

src/IECorePython/CubicBasisBinding.cpp

@@ -121,6 +121,7 @@ void bindCubicBasis( const char *name )
 		.def( "bezier", &T::bezier, return_value_policy<copy_const_reference>() ).staticmethod( "bezier" )
 		.def( "bSpline", &T::bSpline, return_value_policy<copy_const_reference>() ).staticmethod( "bSpline" )
 		.def( "catmullRom", &T::catmullRom, return_value_policy<copy_const_reference>() ).staticmethod( "catmullRom" )
+		.def( "constant", &T::constant, return_value_policy<copy_const_reference>() ).staticmethod( "constant" )
 		.def( "standardBasis", &T::standardBasis )
 		.def( "__repr__", &repr<T> )
 	;
@@ -135,6 +136,7 @@ void bindCubicBasis()
 		.value("Bezier", IECore::StandardCubicBasis::Bezier )
 		.value("BSpline", IECore::StandardCubicBasis::BSpline )
 		.value("CatmullRom", IECore::StandardCubicBasis::CatmullRom )
+		.value("Constant", IECore::StandardCubicBasis::Constant )
 		.export_values()
 		;
 

src/IECoreScene/CurvesAlgoUpdateEndpointMultiplicity.cpp

@@ -107,6 +107,10 @@ int requiredMultiplicity( const IECore::CubicBasisf &cubicBasis )
 	{
 		return 1;
 	}
+	else if( cubicBasis == IECore::CubicBasisf::constant() )
+	{
+		return 1;
+	}
 	else
 	{
 		throw IECore::Exception( "updateEndPointMultiplicity : Unsupported curve basis" );