src/jexer/tterminal/DisplayLine.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * License: LGPLv3 or later
   5  *
   6  * This module is licensed under the GNU Lesser General Public License
   7  * Version 3.  Please see the file "COPYING" in this directory for more
   8  * information about the GNU Lesser General Public License Version 3.
   9  *
  10  *     Copyright (C) 2015  Kevin Lamonte
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU Lesser General Public License
  14  * as published by the Free Software Foundation; either version 3 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  * General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public
  23  * License along with this program; if not, see
  24  * http://www.gnu.org/licenses/, or write to the Free Software
  25  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  26  * 02110-1301 USA
  27  *
  28  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  29  * @version 1
  30  */
  31 package jexer.tterminal;
  32
  33 import jexer.bits.Cell;
  34 import jexer.bits.CellAttributes;
  35
  36 /**
  37  * This represents a single line of the display buffer.
  38  */
  39 public final class DisplayLine {
  40     /**
  41      * Maximum line length.
  42      */
  43     private static final int MAX_LINE_LENGTH = 256;
  44
  45     /**
  46      * The characters/attributes of the line.
  47      */
  48     private Cell [] chars;
  49
  50     /**
  51      * Get the Cell at a specific column.
  52      *
  53      * @param idx the character index
  54      * @return the Cell
  55      */
  56     public Cell charAt(final int idx) {
  57         return chars[idx];
  58     }
  59
  60     /**
  61      * Get the length of this line.
  62      *
  63      * @return line length
  64      */
  65     public int length() {
  66         return chars.length;
  67     }
  68
  69     /**
  70      * Double-width line flag.
  71      */
  72     private boolean doubleWidth = false;
  73
  74     /**
  75      * Get double width flag.
  76      *
  77      * @return double width
  78      */
  79     public boolean isDoubleWidth() {
  80         return doubleWidth;
  81     }
  82
  83     /**
  84      * Set double width flag.
  85      *
  86      * @param doubleWidth new value for double width flag
  87      */
  88     public void setDoubleWidth(final boolean doubleWidth) {
  89         this.doubleWidth = doubleWidth;
  90     }
  91
  92     /**
  93      * Double height line flag.  Valid values are:
  94      *
  95      * <p><pre>
  96      *   0 = single height
  97      *   1 = top half double height
  98      *   2 = bottom half double height
  99      * </pre>
 100      */
 101     private int doubleHeight = 0;
 102
 103     /**
 104      * Get double height flag.
 105      *
 106      * @return double height
 107      */
 108     public int getDoubleHeight() {
 109         return doubleHeight;
 110     }
 111
 112     /**
 113      * Set double height flag.
 114      *
 115      * @param doubleHeight new value for double height flag
 116      */
 117     public void setDoubleHeight(final int doubleHeight) {
 118         this.doubleHeight = doubleHeight;
 119     }
 120
 121     /**
 122      * DECSCNM - reverse video.  We copy the flag to the line so that
 123      * reverse-mode scrollback lines still show inverted colors correctly.
 124      */
 125     private boolean reverseColor = false;
 126
 127     /**
 128      * Get reverse video flag.
 129      *
 130      * @return reverse video
 131      */
 132     public boolean isReverseColor() {
 133         return reverseColor;
 134     }
 135
 136     /**
 137      * Set double-height flag.
 138      *
 139      * @param reverseColor new value for reverse video flag
 140      */
 141     public void setReverseColor(final boolean reverseColor) {
 142         this.reverseColor = reverseColor;
 143     }
 144
 145     /**
 146      * Public constructor sets everything to drawing attributes.
 147      *
 148      * @param attr current drawing attributes
 149      */
 150     public DisplayLine(final CellAttributes attr) {
 151         chars = new Cell[MAX_LINE_LENGTH];
 152         for (int i = 0; i < chars.length; i++) {
 153             chars[i] = new Cell();
 154             chars[i].setTo(attr);
 155         }
 156     }
 157
 158     /**
 159      * Insert a character at the specified position.
 160      *
 161      * @param idx the character index
 162      * @param newCell the new Cell
 163      */
 164     public void insert(final int idx, final Cell newCell) {
 165         System.arraycopy(chars, idx, chars, idx + 1, chars.length - idx - 1);
 166         chars[idx] = newCell;
 167     }
 168
 169     /**
 170      * Replace character at the specified position.
 171      *
 172      * @param idx the character index
 173      * @param newCell the new Cell
 174      */
 175     public void replace(final int idx, final Cell newCell) {
 176         chars[idx].setTo(newCell);
 177     }
 178
 179     /**
 180      * Set the Cell at the specified position to the blank (reset).
 181      *
 182      * @param idx the character index
 183      */
 184     public void setBlank(final int idx) {
 185         chars[idx].reset();
 186     }
 187
 188     /**
 189      * Set the character (just the char, not the attributes) at the specified
 190      * position to ch.
 191      *
 192      * @param idx the character index
 193      * @param ch the new char
 194      */
 195     public void setChar(final int idx, final char ch) {
 196         chars[idx].setChar(ch);
 197     }
 198
 199     /**
 200      * Set the attributes (just the attributes, not the char) at the
 201      * specified position to attr.
 202      *
 203      * @param idx the character index
 204      * @param attr the new attributes
 205      */
 206     public void setAttr(final int idx, final CellAttributes attr) {
 207         chars[idx].setAttr(attr);
 208     }
 209
 210     /**
 211      * Delete character at the specified position, filling in the new
 212      * character on the right with newCell.
 213      *
 214      * @param idx the character index
 215      * @param newCell the new Cell
 216      */
 217     public void delete(final int idx, final Cell newCell) {
 218         System.arraycopy(chars, idx + 1, chars, idx, chars.length - idx - 1);
 219         chars[chars.length - 1] = newCell;
 220     }
 221
 222 }