OpenImageIOAlgo : Add missing array handlers to data()

And consolidate the existing array handling to use the same templated function as everything else. This new version is preferable because it doesn't initialise the data twice (previously the `resize()` was doing a redundant initialisation prior to the `copy()`).

This fixes the loading of ICCProfile metadata, which is the underlying problem reported in https://groups.google.com/g/gaffer-dev/c/qUSJ-r0XuYI/m/y4OMtrBUAAAJ.

Author: johnhaddon

Changes

@@ -1,7 +1,10 @@
 10.5.x.x (relative to 10.5.9.0)
 ========
 
+Fixes
+-----
 
+- OpenImageIOAlgo : Fixed `data()` handling of arrays of type `TypeDesc::CHAR`, `TypeDesc::UCHAR`, `TypeDesc::USHORT`, `TypeDesc::SHORT`, `TypeDesc::UINT` and `TypeDesc::HALF`. Among other things, this fixes the round-tripping of ICC profiles in ImageReader/ImageWriter.
 
 10.5.9.x (relative to 10.5.8.0)
 ========

src/IECoreImage/OpenImageIOAlgo.cpp

@@ -83,6 +83,24 @@ OIIO::TypeDesc extractStringCharPointers( const std::vector<T> &strings, std::ve
 	return type;
 }
 
+template<typename T>
+DataPtr extractScalarData( const OIIO::ParamValue &value )
+{
+	const T *data = static_cast<const T *>( value.data() );
+	if( value.type().arraylen == 0 )
+	{
+		return new TypedData<T>( *data );
+	}
+	else if( value.type().arraylen > 0 )
+	{
+		using DataType = TypedData<std::vector<T>>;
+		typename DataType::Ptr result = new DataType;
+		result->writable().insert( result->writable().end(), data, data + value.type().arraylen );
+		return result;
+	}
+	return nullptr;
+}
+
 }  // namespace
 
 namespace IECoreImage
@@ -566,15 +584,15 @@ IECore::DataPtr data( const OIIO::ParamValue &value )
 		{
 			if ( type.aggregate == TypeDesc::SCALAR )
 			{
-				return new CharData( *static_cast<const char *>( value.data() ) );
+				return extractScalarData<char>( value );
 			}
 			return nullptr;
 		}
 		case TypeDesc::UCHAR :
 		{
 			if ( type.aggregate == TypeDesc::SCALAR )
 			{
-				return new UCharData( *static_cast<const unsigned char *>( value.data() ) );
+				return extractScalarData<unsigned char>( value );
 			}
 			return nullptr;
 		}
@@ -606,30 +624,30 @@ IECore::DataPtr data( const OIIO::ParamValue &value )
 		{
 			if ( type.aggregate == TypeDesc::SCALAR )
 			{
-				return new UShortData( *static_cast<const unsigned short *>( value.data() ) );
+				return extractScalarData<unsigned short>( value );
 			}
 			return nullptr;
 		}
 		case TypeDesc::SHORT :
 		{
 			if ( type.aggregate == TypeDesc::SCALAR )
 			{
-				return new ShortData( *static_cast<const short *>( value.data() ) );
+				return extractScalarData<short>( value );
 			}
 			return nullptr;
 		}
 		case TypeDesc::UINT :
 		{
 			if ( type.aggregate == TypeDesc::SCALAR )
 			{
-				const unsigned *typedData = static_cast<const unsigned *>( value.data() );
 				if ( type.vecsemantics == TypeDesc::TIMECODE )
 				{
+					const unsigned *typedData = static_cast<const unsigned *>( value.data() );
 					return new TimeCodeData( Imf::TimeCode( typedData[0], typedData[1] ) );
 				}
 				else
 				{
-					return new UIntData( *typedData );
+					return extractScalarData<unsigned int>( value );
 				}
 			}
 			return nullptr;
@@ -641,17 +659,7 @@ IECore::DataPtr data( const OIIO::ParamValue &value )
 			{
 				case TypeDesc::SCALAR :
 				{
-					if( !type.arraylen )
-					{
-						return new IntData( *typedData );
-					}
-					else
-					{
-						IntVectorDataPtr vectorData = new IntVectorData();
-						vectorData->writable().resize( type.arraylen );
-						std::copy( &typedData[0], &typedData[type.arraylen], vectorData->writable().begin() );
-						return vectorData;
-					}
+					return extractScalarData<int>( value );
 				}
 				case TypeDesc::VEC2 :
 				{
@@ -696,7 +704,7 @@ IECore::DataPtr data( const OIIO::ParamValue &value )
 		{
 			if ( type.aggregate == TypeDesc::SCALAR )
 			{
-				return new HalfData( *static_cast<const half *>( value.data() ) );
+				return extractScalarData<half>( value );
 			}
 			return nullptr;
 		}
@@ -707,17 +715,7 @@ IECore::DataPtr data( const OIIO::ParamValue &value )
 			{
 				case TypeDesc::SCALAR :
 				{
-					if( !type.arraylen )
-					{
-						return new FloatData( *typedData );
-					}
-					else
-					{
-						FloatVectorDataPtr vectorData = new FloatVectorData();
-						vectorData->writable().resize( type.arraylen );
-						std::copy( &typedData[0], &typedData[type.arraylen], vectorData->writable().begin() );
-						return vectorData;
-					}
+					return extractScalarData<float>( value );
 				}
 				case TypeDesc::VEC2 :
 				{
@@ -764,17 +762,7 @@ IECore::DataPtr data( const OIIO::ParamValue &value )
 			{
 				case TypeDesc::SCALAR :
 				{
-					if( !type.arraylen )
-					{
-						return new DoubleData( *typedData );
-					}
-					else
-					{
-						DoubleVectorDataPtr vectorData = new DoubleVectorData();
-						vectorData->writable().resize( type.arraylen );
-						std::copy( &typedData[0], &typedData[type.arraylen], vectorData->writable().begin() );
-						return vectorData;
-					}
+					return extractScalarData<double>( value );
 				}
 				case TypeDesc::VEC2 :
 				{