kolourpaint/compat/kpBug.h

   1
   2 /*
   3    Copyright (c) 2003-2007 Clarence Dang <dang@kde.org>
   4    All rights reserved.
   5
   6    Redistribution and use in source and binary forms, with or without
   7    modification, are permitted provided that the following conditions
   8    are met:
   9
  10    1. Redistributions of source code must retain the above copyright
  11       notice, this list of conditions and the following disclaimer.
  12    2. Redistributions in binary form must reproduce the above copyright
  13       notice, this list of conditions and the following disclaimer in the
  14       documentation and/or other materials provided with the distribution.
  15
  16    THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18    OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19    IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21    NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22    DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23    THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24    (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25    THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26 */
  27
  28
  29 #ifndef KP_BUG_H
  30 #define KP_BUG_H
  31
  32
  33 class QAbstractButton;
  34 class QButtonGroup;
  35 class QRect;
  36
  37
  38 /**
  39  * @short Hacks around Qt and KDE library bugs (until they're fixed).
  40  *
  41  * SYNC: Remove hacks when fixed.
  42  *
  43  * @author Clarence Dang <dang@kde.org>
  44  */
  45 class kpBug
  46 {
  47 public:
  48     // http://www.trolltech.com/developer/tasktracker.html?method=entry&id=108906:
  49     //
  50     // Qt 4.1.1 QButtonGroup::checkedButton() does not return 0 after a
  51     // button is unchecked.
  52     //
  53     //
  54     // QButtonGroup_CheckedButton() will return 0 correctly.
  55     static QAbstractButton *QButtonGroup_CheckedButton (const QButtonGroup *buttonGroup);
  56
  57     // From: Clarence Dang <dang@kde.org>
  58     // To: qt-bugs@trolltech.com
  59     // Subject: Re: [Issue N108897] Dangerous, subtle change to QRect::normalize()
  60     // Date: Fri, 31 Mar 2006 20:51:36 +1000
  61     // Cc: kde-core-devel@kde.org
  62     //
  63     // Thread extracts:
  64     //
  65     // Qt 4.1.1 qt-copy/src/corelib/tools/qrect.cpp:
  66     //
  67     //     QRect QRect::normalized() const
  68     //     {
  69     //         if (isNull() || width() == 0 || height() == 0)
  70     //             return *this;
  71     //
  72     // This check was not in Qt3.  It is also wrong.
  73     //
  74     // e.g. QRect rect = QRect (thisPoint, lastPoint).normalize ()
  75     //
  76     // This innocent looking line will work for all values of "thisPoint" and
  77     // "lastPoint", _except_ for 5 special cases by my count:
  78     //
  79     //     +++
  80     //     +*
  81     //     +
  82     //
  83     // Where "*" is the topLeft point and "+" are the troublesome bottomRight
  84     // points.
  85     //
  86     //
  87     // QRect_Normalized() will use the Qt3 behaviour and therefore, work for
  88     // all input.
  89     static QRect QRect_Normalized (const QRect &rect);
  90 };
  91
  92
  93 #endif  // KP_BUG_H