/************************************************************************* * * $RCSfile: interpolation.hxx,v $ * * $Revision: 1.2 $ * * last change: $Author: kz $ $Date: 2005-01-21 16:59:59 $ * * The Contents of this file are made available subject to the terms of * either of the following licenses * * - GNU Lesser General Public License Version 2.1 * - Sun Industry Standards Source License Version 1.1 * * Sun Microsystems Inc., October, 2000 * * GNU Lesser General Public License Version 2.1 * ============================================= * Copyright 2000 by Sun Microsystems, Inc. * 901 San Antonio Road, Palo Alto, CA 94303, USA * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License version 2.1, as published by the Free Software Foundation. * * This library 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 for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, * MA 02111-1307 USA * * * Sun Industry Standards Source License Version 1.1 * ================================================= * The contents of this file are subject to the Sun Industry Standards * Source License Version 1.1 (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.openoffice.org/license.html. * * Software provided under this License is provided on an "AS IS" basis, * WITHOUT WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, * WITHOUT LIMITATION, WARRANTIES THAT THE SOFTWARE IS FREE OF DEFECTS, * MERCHANTABLE, FIT FOR A PARTICULAR PURPOSE, OR NON-INFRINGING. * See the License for the specific provisions governing your rights and * obligations concerning the Software. * * The Initial Developer of the Original Code is: Sun Microsystems, Inc. * * Copyright: 2000 by Sun Microsystems, Inc. * * All Rights Reserved. * * Contributor(s): _______________________________________ * * ************************************************************************/ #ifndef _SLIDESHOW_INTERPOLATION_HXX #define _SLIDESHOW_INTERPOLATION_HXX #include namespace presentation { namespace internal { // Interpolator specializations // ============================ // NOTE: generic lerp is included from lerp.hxx. Following // are some specializations for various // not-straight-forward-interpolatable types /// Specialization for RGBColor, to employ color-specific interpolator template<> RGBColor lerp< RGBColor >( const RGBColor& rFrom, const RGBColor& rTo, double t ) { return interpolate( rFrom, rTo, t ); } /// Specialization also for sal_Int16, although this code should not be called template<> sal_Int16 lerp< sal_Int16 >( const sal_Int16&, const sal_Int16& rTo, double ) { OSL_ENSURE( false, "lerp called" ); return rTo; } /// Specialization also for string, although this code should not be called template<> ::rtl::OUString lerp< ::rtl::OUString >( const ::rtl::OUString&, const ::rtl::OUString& rTo, double ) { OSL_ENSURE( false, "lerp<::rtl::OUString> called" ); return rTo; } /// Specialization also for bool, although this code should not be called template<> bool lerp< bool >( const bool&, const bool& rTo, double ) { OSL_ENSURE( false, "lerp called" ); return rTo; } template< typename ValueType > struct Interpolator { ValueType operator()( const ValueType& rFrom, const ValueType& rTo, double t ) const { return lerp( rFrom, rTo, t ); } }; /// Specialization for HSLColor, to employ color-specific interpolator template<> struct Interpolator< HSLColor > { Interpolator( bool bCCW ) : mbCCW( bCCW ) { } HSLColor operator()( const HSLColor& rFrom, const HSLColor& rTo, double t ) const { return interpolate( rFrom, rTo, t, mbCCW ); } private: /// When true: interpolate counter-clockwise const bool mbCCW; }; /** Generic linear interpolator @tpl ValueType Must have operator+ and operator* defined, and should have value semantics. @param rInterpolator Interpolator to use for lerp @param nFrame Must be in the [0,nTotalFrames) range @param nTotalFrames Total number of frames. Should be greater than zero. */ template< typename ValueType > ValueType lerp( const Interpolator< ValueType >& rInterpolator, const ValueType& rFrom, const ValueType& rTo, sal_uInt32 nFrame, ::std::size_t nTotalFrames ) { // TODO(P1): There's a nice HAKMEM trick for that // nTotalFrames > 1 condition below // for 1 and 0 frame animations, always take end value const double nFraction( nTotalFrames > 1 ? (double)nFrame/(nTotalFrames-1) : 1.0 ); return rInterpolator( rFrom, rTo, nFraction ); } /// Specialization for non-interpolatable constants/enums template<> sal_Int16 lerp< sal_Int16 >( const Interpolator< sal_Int16 >& rInterpolator, const sal_Int16& rFrom, const sal_Int16& rTo, sal_uInt32 nFrame, ::std::size_t nTotalFrames ) { // until one half of the total frames are over, take from value. // after that, take to value. // For nFrames not divisable by 2, we prefer to over from, which // also neatly yields to for 1 frame activities return nFrame < nTotalFrames/2 ? rFrom : rTo; } /// Specialization for non-interpolatable strings template<> ::rtl::OUString lerp< ::rtl::OUString >( const Interpolator< ::rtl::OUString >& rInterpolator, const ::rtl::OUString& rFrom, const ::rtl::OUString& rTo, sal_uInt32 nFrame, ::std::size_t nTotalFrames ) { // until one half of the total frames are over, take from value. // after that, take to value. // For nFrames not divisable by 2, we prefer to over from, which // also neatly yields to for 1 frame activities return nFrame < nTotalFrames/2 ? rFrom : rTo; } /// Specialization for non-interpolatable bools template<> bool lerp< bool >( const Interpolator< bool >& rInterpolator, const bool& bFrom, const bool& bTo, sal_uInt32 nFrame, ::std::size_t nTotalFrames ) { // until one half of the total frames are over, take from value. // after that, take to value. // For nFrames not divisable by 2, we prefer to over from, which // also neatly yields to for 1 frame activities return nFrame < nTotalFrames/2 ? bFrom : bTo; } } } #endif /* _SLIDESHOW_INTERPOLATION_HXX */