Line data    Source code

       1             : /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
       2             : /*
       3             :  * This file is part of the LibreOffice project.
       4             :  *
       5             :  * This Source Code Form is subject to the terms of the Mozilla Public
       6             :  * License, v. 2.0. If a copy of the MPL was not distributed with this
       7             :  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
       8             :  *
       9             :  * This file incorporates work covered by the following license notice:
      10             :  *
      11             :  *   Licensed to the Apache Software Foundation (ASF) under one or more
      12             :  *   contributor license agreements. See the NOTICE file distributed
      13             :  *   with this work for additional information regarding copyright
      14             :  *   ownership. The ASF licenses this file to you under the Apache
      15             :  *   License, Version 2.0 (the "License"); you may not use this file
      16             :  *   except in compliance with the License. You may obtain a copy of
      17             :  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
      18             :  */
      19             : 
      20             : #ifndef INCLUDED_BASEBMP_STRIDEDARRAYITERATOR_HXX
      21             : #define INCLUDED_BASEBMP_STRIDEDARRAYITERATOR_HXX
      22             : 
      23             : #include <basebmp/metafunctions.hxx>
      24             : 
      25             : namespace basebmp
      26             : {
      27             : 
      28             : /** Like vigra::StridedArrayIterator
      29             : 
      30             :     Changed semantics re. DirectionSelector<StridedArrayTag>: stride
      31             :     now counts in <em>raw</em> bytes
      32             : 
      33             :     Adapts given ptr, in a way that iterator increments move forward
      34             :     in strided steps. Stride can, by the way, also be negative
      35             :  */
      36             : template< typename T > class StridedArrayIterator
      37             : {
      38             : public:
      39             :     typedef typename clone_const<T, unsigned char>::type  internal_type;
      40             : 
      41             :     /** Create iterator
      42             : 
      43             :         @param stride
      44             : 
      45             :         Stride in bytes. Given value should better match memory layout
      46             :         of T, as memory gets reinterpret-casted.
      47             :      */
      48           0 :     explicit StridedArrayIterator(int stride, T* ptr = 0) :
      49             :         stride_(stride),
      50           0 :         current_(reinterpret_cast<internal_type*>(ptr))
      51           0 :     {}
      52             : 
      53             :     /** Copy from other StridedArrayIterator, plus given offset
      54             : 
      55             :         @param offset
      56             :         Offset in bytes
      57             :      */
      58           0 :     StridedArrayIterator( StridedArrayIterator const& rSrc,
      59             :                           int                         offset ) :
      60             :         stride_(rSrc.stride_),
      61             :         current_(reinterpret_cast<internal_type*>(
      62           0 :                      reinterpret_cast<T*>(rSrc.current_)+offset))
      63           0 :     {}
      64             : 
      65           0 :     void operator++()       {current_ += stride_; }
      66             :     void operator++(int)    {current_ += stride_; }
      67             :     void operator--()       {current_ -= stride_; }
      68             :     void operator--(int)    {current_ -= stride_; }
      69           0 :     void operator+=(int dy) {current_ += dy*stride_; }
      70             :     void operator-=(int dy) {current_ -= dy*stride_; }
      71             : 
      72           0 :     int operator-(StridedArrayIterator const & rhs) const
      73           0 :     { return (current_ - rhs.current_) / stride_; }
      74             : 
      75           0 :     bool operator==(StridedArrayIterator const & rhs) const
      76           0 :     { return current_ == rhs.current_; }
      77             : 
      78             :     bool operator!=(StridedArrayIterator const & rhs) const
      79             :     { return current_ != rhs.current_; }
      80             : 
      81           0 :     bool operator<(StridedArrayIterator const & rhs) const
      82           0 :     { return *this - rhs < 0; }
      83             : 
      84             :     bool operator<=(StridedArrayIterator const & rhs) const
      85             :     { return *this - rhs <= 0; }
      86             : 
      87             :     bool operator>(StridedArrayIterator const & rhs) const
      88             :     { return *this - rhs > 0; }
      89             : 
      90             :     bool operator>=(StridedArrayIterator const & rhs) const
      91             :     { return *this - rhs >= 0; }
      92             : 
      93           0 :     T* operator()() const
      94           0 :     { return reinterpret_cast<T*>(current_); }
      95             : 
      96             :     T* operator()(int d) const
      97             :     { return reinterpret_cast<T*>(current_ + d*stride_); }
      98             : 
      99             : private:
     100             :     int            stride_;
     101             :     internal_type* current_;
     102             : };
     103             : 
     104             : } // namespace basebmp
     105             : 
     106             : #endif /* INCLUDED_BASEBMP_STRIDEDARRAYITERATOR_HXX */
     107             : 
     108             : /* vim:set shiftwidth=4 softtabstop=4 expandtab: */