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 *
 * Licensed to the Apache Software Foundation (ASF) under one
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 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
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 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
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#ifndef INCLUDED_BASEBMP_INTCONVERSION_HXX
#define INCLUDED_BASEBMP_INTCONVERSION_HXX

#include <vigra/rgbvalue.hxx>
#include <functional>

namespace basebmp
{
	// metafunctions to retrieve correct POD from/to basebmp::Color
	//------------------------------------------------------------------------

	// type-safe conversion from RgbValue to packed int32
	template< class RgbVal > struct UInt32FromRgbValue
	{
		sal_uInt32 operator()( RgbVal const& c ) const
		{
			return (c[0] << 16) | (c[1] << 8) | c[2];
		}
	};

	// type-safe conversion from packed int32 to RgbValue
	template< class RgbVal > struct RgbValueFromUInt32
	{
		RgbVal operator()( sal_uInt32 c ) const
		{
			return RgbVal((c >> 16) & 0xFF,
						  (c >> 8) & 0xFF,
						  c & 0xFF);
		}
	};

	// Get converter from given data type to sal_uInt32
	template< typename DataType > struct uInt32Converter
	{
		typedef std::identity<DataType> to;
		typedef std::identity<DataType> from;
	};
	template< unsigned int RedIndex,
			  unsigned int GreenIndex,
			  unsigned int BlueIndex > struct uInt32Converter<
				  vigra::RGBValue< sal_uInt8,
								   RedIndex,
								   GreenIndex,
								   BlueIndex > >
	{
		typedef UInt32FromRgbValue<
			vigra::RGBValue< sal_uInt8,
							 RedIndex,
							 GreenIndex,
							 BlueIndex > >
			to;
		typedef RgbValueFromUInt32<
			vigra::RGBValue< sal_uInt8,
							 RedIndex,
							 GreenIndex,
							 BlueIndex > >
			from;
	};
}

#endif /* INCLUDED_BASEBMP_INTCONVERSION_HXX */

/* vim: set noet sw=4 ts=4: */