src/screen.C

   1 /* This file is part of
   2 * ======================================================
   3 *
   4 *           LyX, The Document Processor
   5 *
   6 *           Copyright 1995 Matthias Ettrich
   7 *           Copyright 1995-1998 The LyX Team
   8 *
   9 * ====================================================== */
  10
  11 #include <config.h>
  12
  13 #ifdef __GNUG__
  14 #pragma implementation "lyxscreen.h"
  15 #endif
  16
  17 #include <algorithm>
  18
  19 #include "lyxscreen.h"
  20 #include "lyxtext.h"
  21 #include "lyxrow.h"
  22 #include "Painter.h"
  23 #include "WorkArea.h"
  24 #include "buffer.h"
  25 #include "font.h"
  26
  27 using std::max;
  28 using std::min;
  29
  30 static
  31 GC createGC()
  32 {
  33         XGCValues val;
  34         val.foreground = BlackPixel(fl_display,
  35                                     DefaultScreen(fl_display));
  36
  37         val.function=GXcopy;
  38         val.graphics_exposures = false;
  39         val.line_style = LineSolid;
  40         val.line_width = 0;
  41         return XCreateGC(fl_display, RootWindow(fl_display, 0),
  42                          GCForeground | GCFunction | GCGraphicsExposures
  43                          | GCLineWidth | GCLineStyle , &val);
  44 }
  45
  46
  47 // Constructor
  48 LyXScreen::LyXScreen(WorkArea & o, LyXText * text_ptr)
  49         : owner(o), text(text_ptr)
  50 {
  51         first = 0;
  52
  53         // the cursor isnt yet visible
  54         cursor_visible = false;
  55         cursor_pixmap = 0;
  56         cursor_pixmap_x = 0;
  57         cursor_pixmap_y = 0;
  58         cursor_pixmap_w = 0;
  59         cursor_pixmap_h = 0;
  60
  61         // We need this GC
  62         gc_copy = createGC();
  63 }
  64
  65
  66 void LyXScreen::Redraw()
  67 {
  68         DrawFromTo(0, owner.height());
  69         expose(0, 0, owner.workWidth(), owner.height());
  70         if (cursor_visible) {
  71                 cursor_visible = false;
  72                 ShowCursor();
  73         }
  74 }
  75
  76
  77 void LyXScreen::expose(int x, int y, int exp_width, int exp_height)
  78 {
  79         XCopyArea(fl_display,
  80                   owner.getPixmap(),
  81                   owner.getWin(),
  82                   gc_copy,
  83                   x, y,
  84                   exp_width, exp_height,
  85                   x + owner.xpos(),
  86                   y + owner.ypos());
  87 }
  88
  89
  90 void LyXScreen::DrawFromTo(int y1, int y2)
  91 {
  92         long y_text = first + y1;
  93
  94         // get the first needed row
  95         Row * row = text->GetRowNearY(y_text);
  96         // y_text is now the real beginning of the row
  97
  98         long y = y_text - first;
  99         // y1 is now the real beginning of row on the screen
 100
 101         while (row != 0 && y < y2) {
 102                 text->GetVisibleRow(y, row, y + first);
 103                 y += row->height;
 104                 row = row->next;
 105         }
 106
 107         // maybe we have to clear the screen at the bottom
 108         if (y < y2) {
 109                 owner.getPainter().fillRectangle(0, y,
 110                                                  owner.workWidth(),
 111                                                  y2 - y,
 112                                                LColor::bottomarea);
 113         }
 114 }
 115
 116
 117 void LyXScreen::DrawOneRow(Row * row, long y_text)
 118 {
 119         long y = y_text - first;
 120
 121         if (y + row->height > 0 && y - row->height <= long(owner.height())) {
 122                 // ok there is something visible
 123                 text->GetVisibleRow(y, row, y + first);
 124         }
 125 }
 126
 127
 128 /* draws the screen, starting with textposition y. uses as much already
 129 * printed pixels as possible */
 130 void LyXScreen::Draw(unsigned long y)
 131 {
 132         if (cursor_visible) HideCursor();
 133
 134         unsigned long old_first = first;
 135         first = y;
 136
 137         // is any optimiziation possible?
 138         if ((y - old_first) < owner.height()
 139             && (old_first - y) < owner.height()) {
 140                 if (first < old_first) {
 141                         DrawFromTo(0, old_first - first);
 142                         XCopyArea (fl_display,
 143                                    owner.getWin(),
 144                                    owner.getWin(),
 145                                    gc_copy,
 146                                    owner.xpos(),
 147                                    owner.ypos(),
 148                                    owner.workWidth(),
 149                                    owner.height() - old_first + first,
 150                                    owner.xpos(),
 151                                    owner.ypos() + old_first - first
 152                                 );
 153                         // expose the area drawn
 154                         expose(0, 0,
 155                                owner.workWidth(),
 156                                old_first - first);
 157                 } else  {
 158                         DrawFromTo(
 159                                 owner.height() + old_first - first,
 160                                    owner.height());
 161                         XCopyArea (fl_display,
 162                                    owner.getWin(),
 163                                    owner.getWin(),
 164                                    gc_copy,
 165                                    owner.xpos(),
 166                                    owner.ypos() + first - old_first,
 167                                    owner.workWidth(),
 168                                    owner.height() + old_first - first,
 169                                    owner.xpos(),
 170                                    owner.ypos());
 171                         // expose the area drawn
 172                         expose(0, owner.height() + old_first - first,
 173                                owner.workWidth(), first - old_first);
 174                 }
 175         } else {
 176                 // make a dumb new-draw
 177                 DrawFromTo(0, owner.height());
 178                 expose(0, 0, owner.workWidth(), owner.height());
 179         }
 180 }
 181
 182
 183 void LyXScreen::ShowCursor()
 184 {
 185         if (!cursor_visible) {
 186                 Cursor_Shape shape = BAR_SHAPE;
 187                 if (text->real_current_font.language() !=
 188                     text->buffer->params.language_info
 189                     || text->real_current_font.isVisibleRightToLeft()
 190                     != text->buffer->params.language_info->RightToLeft)
 191                         shape = (text->real_current_font.isVisibleRightToLeft())
 192                                 ? REVERSED_L_SHAPE : L_SHAPE;
 193                 ShowManualCursor(text->cursor.x, text->cursor.y,
 194                                  lyxfont::maxAscent(text->real_current_font),
 195                                  lyxfont::maxDescent(text->real_current_font),
 196                                  shape);
 197         }
 198 }
 199
 200
 201 /* returns true if first has changed, otherwise false */
 202 bool LyXScreen::FitManualCursor(long /*x*/, long y, int asc, int desc)
 203 {
 204         long newtop = first;
 205
 206         if (y + desc - first >= owner.height())
 207                 newtop = y - 3 * owner.height() / 4;  // the scroll region must be so big!!
 208         else if (y - asc < long(first)
 209                 && first > 0) {
 210                 newtop = y - owner.height() / 4;
 211         }
 212
 213         newtop = max(newtop, 0L); // can newtop ever be < 0? (Lgb)
 214
 215         if (newtop != long(first)) {
 216                 Draw(newtop);
 217                 first = newtop;
 218                 return true;
 219         }
 220         return false;
 221 }
 222
 223
 224 void LyXScreen::ShowManualCursor(long x, long y, int asc, int desc,
 225                                   Cursor_Shape shape)
 226 {
 227         unsigned long y1 = max(y - first - asc, 0UL);
 228         typedef unsigned long ulong;
 229
 230         unsigned long y2 = min(y - first + desc, ulong(owner.height()));
 231
 232         // Secure against very strange situations
 233         y2 = max(y2, y1);
 234
 235         if (cursor_pixmap){
 236                 XFreePixmap(fl_display, cursor_pixmap);
 237                 cursor_pixmap = 0;
 238         }
 239
 240         if (y2 > 0 && y1 < owner.height()) {
 241                 cursor_pixmap_h = y2 - y1 + 1;
 242                 cursor_pixmap_y = y1;
 243
 244                 switch(shape) {
 245                 case BAR_SHAPE:
 246                         cursor_pixmap_w = 1;
 247                         cursor_pixmap_x = x;
 248                         break;
 249                 case L_SHAPE:
 250                         cursor_pixmap_w = cursor_pixmap_h/3;
 251                         cursor_pixmap_x = x;
 252                         break;
 253                 case REVERSED_L_SHAPE:
 254                         cursor_pixmap_w = cursor_pixmap_h/3;
 255                         cursor_pixmap_x = x - cursor_pixmap_w + 1;
 256                         break;
 257                 }
 258
 259                 cursor_pixmap =
 260                         XCreatePixmap (fl_display,
 261                                        fl_root,
 262                                        cursor_pixmap_w,
 263                                        cursor_pixmap_h,
 264                                        fl_get_visual_depth());
 265                 XCopyArea (fl_display,
 266                            owner.getWin(),
 267                            cursor_pixmap,
 268                            gc_copy,
 269                            owner.xpos() + cursor_pixmap_x,
 270                            owner.ypos() + cursor_pixmap_y,
 271                            cursor_pixmap_w,
 272                            cursor_pixmap_h,
 273                            0, 0);
 274                 XDrawLine(fl_display,
 275                           owner.getWin(),
 276                           gc_copy,
 277                           x + owner.xpos(),
 278                           y1 + owner.ypos(),
 279                           x + owner.xpos(),
 280                           y2 + owner.ypos());
 281                 switch(shape) {
 282                 case BAR_SHAPE:
 283                         break;
 284                 case L_SHAPE:
 285                 case REVERSED_L_SHAPE:
 286                         int rectangle_h = (cursor_pixmap_h+10)/20;
 287                         XFillRectangle(fl_display,
 288                                        owner.getWin(),
 289                                        gc_copy,
 290                                        cursor_pixmap_x + owner.xpos(),
 291                                        y2 - rectangle_h + 1 + owner.ypos(),
 292                                        cursor_pixmap_w - 1, rectangle_h);
 293                         break;
 294                 }
 295
 296         }
 297         cursor_visible = true;
 298 }
 299
 300
 301 void LyXScreen::HideCursor()
 302 {
 303         if (!cursor_visible) return;
 304
 305         if (cursor_pixmap){
 306                 XCopyArea (fl_display,
 307                            cursor_pixmap,
 308                            owner.getWin(),
 309                            gc_copy,
 310                            0, 0,
 311                            cursor_pixmap_w, cursor_pixmap_h,
 312                            cursor_pixmap_x + owner.xpos(),
 313                            cursor_pixmap_y + owner.ypos());
 314         }
 315         cursor_visible = false;
 316 }
 317
 318
 319 void LyXScreen::CursorToggle()
 320 {
 321         if (cursor_visible)
 322                 HideCursor();
 323         else
 324                 ShowCursor();
 325 }
 326
 327
 328 /* returns a new top so that the cursor is visible */
 329 unsigned long LyXScreen::TopCursorVisible()
 330 {
 331         long newtop = first;
 332
 333         if (text->cursor.y
 334             - text->cursor.row->baseline
 335             + text->cursor.row->height
 336             - first >= owner.height()) {
 337                 if (text->cursor.row->height < owner.height()
 338                     && text->cursor.row->height > owner.height() / 4)
 339                         newtop = text->cursor.y
 340                                 + text->cursor.row->height
 341                                 - text->cursor.row->baseline - owner.height();
 342                 else
 343                         newtop = text->cursor.y
 344                                 - 3 * owner.height() / 4;   /* the scroll region must be so big!! */
 345         } else if (text->cursor.y - text->cursor.row->baseline < first
 346                    && first > 0) {
 347                 if (text->cursor.row->height < owner.height()
 348                     && text->cursor.row->height > owner.height() / 4)
 349                         newtop = text->cursor.y - text->cursor.row->baseline;
 350                 else {
 351                         newtop = text->cursor.y - owner.height() / 4;
 352                         newtop = min(newtop, long(first));
 353                 }
 354         }
 355
 356         newtop = max(newtop, 0L);
 357
 358         return newtop;
 359 }
 360
 361
 362 /* scrolls the screen so that the cursor is visible, if necessary.
 363 * returns true if a change was made, otherwise false */
 364 bool LyXScreen::FitCursor()
 365 {
 366         // Is a change necessary?
 367         unsigned long newtop = TopCursorVisible();
 368         bool result = (newtop != first);
 369         if (result)
 370                 Draw(newtop);
 371         return result;
 372 }
 373
 374
 375 void LyXScreen::Update()
 376 {
 377         switch(text->status) {
 378         case LyXText::NEED_MORE_REFRESH:
 379         {
 380                 long y = max(text->refresh_y - long(first), 0L);
 381
 382                 DrawFromTo(y, owner.height());
 383                 text->refresh_y = 0;
 384                 text->status = LyXText::UNCHANGED;
 385                 expose(0, y,
 386                        owner.workWidth(), owner.height() - y);
 387         }
 388         break;
 389         case LyXText::NEED_VERY_LITTLE_REFRESH:
 390         {
 391                 // ok I will update the current cursor row
 392                 DrawOneRow(text->refresh_row, text->refresh_y);
 393                 text->status = LyXText::UNCHANGED;
 394                 expose(0, text->refresh_y - first,
 395                        owner.workWidth(), text->refresh_row->height);
 396         }
 397         break;
 398         case LyXText::UNCHANGED:
 399                 // Nothing needs done
 400                 break;
 401         }
 402 }
 403
 404
 405 void LyXScreen::ToggleSelection(bool kill_selection)
 406 {
 407         // only if there is a selection
 408         if (!text->selection) return;
 409
 410         long bottom = min(max(text->sel_end_cursor.y
 411                               - text->sel_end_cursor.row->baseline
 412                               + text->sel_end_cursor.row->height, first),
 413                           first + owner.height());
 414         long top = min(max(text->sel_start_cursor.y
 415                            - text->sel_start_cursor.row->baseline, first),
 416                        first + owner.height());
 417
 418         if (kill_selection)
 419                 text->selection = 0;
 420         DrawFromTo(top - first, bottom - first);
 421         expose(0, top - first,
 422                owner.workWidth(),
 423                bottom - first - (top - first));
 424 }
 425
 426
 427 void LyXScreen::ToggleToggle()
 428 {
 429         if (text->toggle_cursor.par == text->toggle_end_cursor.par
 430             && text->toggle_cursor.pos == text->toggle_end_cursor.pos)
 431                 return;
 432
 433         long top = text->toggle_cursor.y
 434                 - text->toggle_cursor.row->baseline;
 435         long bottom = text->toggle_end_cursor.y
 436                 - text->toggle_end_cursor.row->baseline
 437                 + text->toggle_end_cursor.row->height;
 438
 439         typedef unsigned long ulong;
 440
 441         bottom = min(max(ulong(bottom), first), first + owner.height());
 442         top = min(max(ulong(top), first), first + owner.height());
 443
 444         DrawFromTo(top - first, bottom - first);
 445         expose(0, top - first, owner.workWidth(),
 446                bottom - first - (top - first));
 447 }