kolourpaint/layers/selections/text/kpTextSelection_Cursor.cpp

   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 #define DEBUG_KP_SELECTION 0
  30
  31
  32 #include <kpTextSelection.h>
  33 #include <kpTextSelectionPrivate.h>
  34
  35 #include <QFontMetrics>
  36 #include <QList>
  37
  38 #include <KDebug>
  39
  40 #include <kpDefs.h>
  41 #include <kpTextStyle.h>
  42
  43
  44 // public
  45 int kpTextSelection::closestTextRowForPoint (const QPoint &point) const
  46 {
  47     if (!pointIsInTextArea (point))
  48         return -1;
  49
  50     const QFontMetrics fontMetrics (d->textStyle.fontMetrics ());
  51
  52     int row = (point.y () - textAreaRect ().y ()) /
  53                fontMetrics.lineSpacing ();
  54     if (row >= (int) d->textLines.size ())
  55         row = d->textLines.size () - 1;
  56
  57     return row;
  58 }
  59
  60 // public
  61 int kpTextSelection::closestTextColForPoint (const QPoint &point) const
  62 {
  63     int row = closestTextRowForPoint (point);
  64     if (row < 0 || row >= (int) d->textLines.size ())
  65         return -1;
  66
  67     const int localX = point.x () - textAreaRect ().x ();
  68
  69     const QFontMetrics fontMetrics (d->textStyle.fontMetrics ());
  70
  71     // (should be 0 but call just in case)
  72     int charLocalLeft = fontMetrics.width (d->textLines [row], 0);
  73
  74     // OPT: binary search or guess location then move
  75     for (int col = 0; col < (int) d->textLines [row].length (); col++)
  76     {
  77         // OPT: fontMetrics::charWidth() might be faster
  78         const int nextCharLocalLeft = fontMetrics.width (d->textLines [row], col + 1);
  79         if (localX <= (charLocalLeft + nextCharLocalLeft) / 2)
  80             return col;
  81
  82         charLocalLeft = nextCharLocalLeft;
  83     }
  84
  85     return d->textLines [row].length ()/*past end of line*/;
  86 }
  87
  88
  89 // public
  90 QPoint kpTextSelection::pointForTextRowCol (int row, int col) const
  91 {
  92     if (row < 0 || row >= (int) d->textLines.size () ||
  93         col < 0 || col > (int) d->textLines [row].length ())
  94     {
  95     #if DEBUG_KP_SELECTION && 1
  96         kDebug () << "kpTextSelection::pointForTextRowCol("
  97                    << row << ","
  98                    << col << ") out of range"
  99                    << " textLines='"
 100                    << text ()
 101                    << "'"
 102                    << endl;
 103     #endif
 104         return KP_INVALID_POINT;
 105     }
 106
 107     const QFontMetrics fontMetrics (d->textStyle.fontMetrics ());
 108
 109     const int x = fontMetrics.width (d->textLines [row], col);
 110     const int y = row * fontMetrics.height () +
 111                   (row >= 1 ? row * fontMetrics.leading () : 0);
 112
 113     return textAreaRect ().topLeft () + QPoint (x, y);
 114 }