mcs/class/System.Drawing/System.Drawing.Text/TextLineIterator.jvm.cs

   1 //
   2 // System.Drawing.Test.TextLineIterator.jvm.cs
   3 //
   4 // Author:
   5 // Konstantin Triger <kostat@mainsoft.com>
   6 //
   7 // Copyright (C) 2005 Mainsoft Corporation, (http://www.mainsoft.com)
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28
  29 using System;
  30 using System.Drawing.Drawing2D;
  31
  32 using font = java.awt.font;\r
  33 using text = java.text;
  34 using awt = java.awt;\r
  35 using geom = java.awt.geom;
  36
  37 namespace System.Drawing.Text {
  38         internal sealed class TextLineIterator {
  39
  40                 #region Fields
  41
  42                 readonly float _width;\r
  43                 readonly float _height;\r
  44                 readonly StringFormat _format;\r
  45                 readonly font.FontRenderContext _frc;
  46                 readonly string _s;
  47                 readonly Font _font;
  48                 readonly float _margin;
  49
  50                 static readonly string NewLine;\r
  51 \r
  52                 static readonly geom.AffineTransform Rotate90Transform = \r
  53                         geom.AffineTransform.getRotateInstance(Math.PI/2);\r
  54 \r
  55                 font.TextMeasurer _measurer;\r
  56                 int _charsConsumed = 0;\r
  57                 int _currentPos = 0;\r
  58                 int _currentRun = 0;\r
  59                 float _accumulatedHeight = 0;\r
  60 \r
  61                 #endregion\r
  62 \r
  63                 #region ctors\r
  64 \r
  65                 static TextLineIterator() {\r
  66                         string newLine = Environment.NewLine;\r
  67                         if (newLine == null || newLine.Length == 0 || newLine[newLine.Length - 1] == '\n')\r
  68                                 newLine = "\n";\r
  69 \r
  70                         NewLine = newLine;\r
  71                 }
  72
  73                 internal TextLineIterator(string s, Font font, font.FontRenderContext frc, StringFormat format, float width, float height) {\r
  74                         _format = (format != null) ? format : new StringFormat();\r
  75                         _font = font;\r
  76                         _s = (s != null) ? s : String.Empty;\r
  77                         _frc = frc;\r
  78                         FontFamily ff = font.FontFamily;\r
  79                         _margin = font.Size*ff.GetDrawMargin(font.Style)/ff.GetEmHeight(font.Style);\r
  80 \r
  81                         _width = width;\r
  82                         _height = height;\r
  83                 }
  84
  85                 #endregion
  86
  87                 #region Properties
  88
  89                 float WrapWidth {
  90                         get { return (_format.IsVertical ? Height : Width) - (Margin * 2); }
  91                 }
  92
  93                 internal float WrapHeight {
  94                         get { return (_format.IsVertical ? Width : Height); }
  95                 }
  96
  97                 internal float Width {
  98                         get { return _width; }
  99                 }
 100
 101                 internal float Height {
 102                         get { return _height; }
 103                 }
 104
 105                 internal StringFormat Format {
 106                         get { return _format; }
 107                 }
 108
 109                 internal float Margin {
 110                         get { return _margin; }
 111                 }
 112
 113                 internal int CharsConsumed {
 114                         get { return _charsConsumed; }
 115                 }
 116
 117                 internal int CurrentRun {
 118                         get { return _currentRun; }
 119                 }
 120
 121                 internal int CurrentPosition {
 122                         get { return _currentPos; }
 123                 }
 124
 125                 internal float AccumulatedHeight {
 126                         get { return _accumulatedHeight; }
 127                 }
 128
 129                 internal float GetAdvanceBetween(int start, int limit) {
 130                         return _measurer.getAdvanceBetween(start, limit);
 131                 }
 132
 133                 internal geom.AffineTransform Transform {
 134                         get { return Format.IsVertical ? Rotate90Transform : Matrix.IdentityTransform.NativeObject; }
 135                 }
 136
 137                 #endregion
 138
 139                 #region Methods
 140
 141                 LineLayout NextTextLayoutFromMeasurer() {
 142                         if (_accumulatedHeight >= WrapHeight) {
 143                                 _charsConsumed += _currentPos;
 144                                 return null;
 145                         }
 146
 147                         int limit = _measurer.getLineBreakIndex(_currentPos, WrapWidth);
 148
 149                         int wordBreak = limit;
 150                         if (wordBreak < _currentRun) {
 151                                 while (wordBreak >= _currentPos && char.IsLetterOrDigit(_s, _charsConsumed + wordBreak))
 152                                         wordBreak--;
 153
 154                                 if (wordBreak > _currentPos)
 155                                         limit = wordBreak + 1;
 156                         }
 157                         font.TextLayout layout = _measurer.getLayout(_currentPos, limit);
 158
 159                         LineLayout lineLayout = new LineLayout(
 160                                 layout,
 161                                 this,
 162                                 _accumulatedHeight);
 163
 164                         float lineHeight = lineLayout.Ascent + lineLayout.Descent;
 165
 166                         if (Format.LineLimit && (_accumulatedHeight + lineHeight > WrapHeight)) {
 167                                 _charsConsumed += _currentPos;
 168                                 return null;
 169                         }
 170
 171                         _accumulatedHeight += lineHeight + lineLayout.Leading;
 172
 173                         _currentPos = limit;
 174
 175                         while (_currentPos < _currentRun) {
 176                                 if (char.IsWhiteSpace(_s, _charsConsumed + _currentPos))
 177                                         _currentPos++;
 178                                 else
 179                                         break;
 180                         }
 181                         return lineLayout;
 182                 }
 183
 184                 internal LineLayout NextLine() {
 185                         if (_currentPos < _currentRun && !Format.NoWrap)
 186                                 return NextTextLayoutFromMeasurer();
 187
 188                         _charsConsumed += _currentRun;
 189                         if (_charsConsumed >= _s.Length)\r
 190                                 return null;\r
 191 \r
 192                         string s;\r
 193                         int lineBreakIndex = _s.IndexOf(NewLine, _charsConsumed);\r
 194                         if (lineBreakIndex >= 0) {\r
 195                                 s = _s.Substring(_charsConsumed, lineBreakIndex - _charsConsumed + NewLine.Length);\r
 196                         }\r
 197                         else\r
 198                                 s = _s.Substring(_charsConsumed);\r
 199 \r
 200                         _currentRun = s.Length;\r
 201                         _currentPos = 0;\r
 202 \r
 203                         text.AttributedString aS = new text.AttributedString(s);\r
 204                                 \r
 205                         // TODO: add more attribs according to StringFormat\r
 206                         aS.addAttribute(font.TextAttribute.FONT, _font.NativeObject);\r
 207                         if((_font.Style & FontStyle.Underline) != FontStyle.Regular)
 208                                 aS.addAttribute(font.TextAttribute.UNDERLINE, font.TextAttribute.UNDERLINE_ON);
 209                         if((_font.Style & FontStyle.Strikeout) != FontStyle.Regular)
 210                                 aS.addAttribute(font.TextAttribute.STRIKETHROUGH, font.TextAttribute.STRIKETHROUGH_ON);\r
 211 \r
 212                         text.AttributedCharacterIterator charIter = aS.getIterator();\r
 213
 214                         _measurer = new font.TextMeasurer(charIter, _frc);
 215                         return NextTextLayoutFromMeasurer();
 216                 }
 217
 218                 internal geom.AffineTransform CalcLineAlignmentTransform() {
 219                         if (Format.LineAlignment == StringAlignment.Near)\r
 220                                 return null;\r
 221                         float height = WrapHeight;\r
 222                         if (float.IsPositiveInfinity(height))\r
 223                                 height = 0;\r
 224 \r
 225                         float shift = height - AccumulatedHeight;\r
 226                         if (height > 0 && shift <= 0)\r
 227                                 return null;\r
 228 \r
 229                         if (Format.LineAlignment == StringAlignment.Center)\r
 230                                 shift /= 2;\r
 231                         else\r
 232                                 if (Format.IsVertical && Format.IsRightToLeft)\r
 233                                 return null;\r
 234 \r
 235                         return Format.IsVertical ?\r
 236                                 geom.AffineTransform.getTranslateInstance(shift, 0) :\r
 237                                 geom.AffineTransform.getTranslateInstance(0, shift);
 238                 }
 239
 240                 #endregion
 241         }
 242 }