/*************************************************************************
 *
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * Copyright 2000, 2010 Oracle and/or its affiliates.
 *
 * OpenOffice.org - a multi-platform office productivity suite
 *
 * This file is part of OpenOffice.org.
 *
 * OpenOffice.org is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License version 3
 * only, as published by the Free Software Foundation.
 *
 * OpenOffice.org is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License version 3 for more details
 * (a copy is included in the LICENSE file that accompanied this code).
 *
 * You should have received a copy of the GNU Lesser General Public License
 * version 3 along with OpenOffice.org.  If not, see
 * <http://www.openoffice.org/license.html>
 * for a copy of the LGPLv3 License.
 *
 ************************************************************************/

#ifndef INCLUDED_SLIDESHOW_LERP_HXX
#define INCLUDED_SLIDESHOW_LERP_HXX

#include <sal/types.h>

namespace slideshow
{
    namespace internal
    {

        /** Generic linear interpolator

            @tpl ValueType
            Must have operator+ and operator* defined, and should
            have value semantics.

            @param t
            As usual, t must be in the [0,1] range
        */
        template< typename ValueType > ValueType lerp( const ValueType&     rFrom,
                                                       const ValueType&     rTo,
                                                       double               t )
        {
            // This is only to suppress a double->int warning. All other
            // types should be okay here.
            return static_cast<ValueType>( (1.0-t)*rFrom + t*rTo );
        }

    }
}

#endif /* INCLUDED_SLIDESHOW_LERP_HXX */