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(owner.owner(), y, 0, 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
 122             && y - row->height() <= long(owner.height())) {
 123                 // ok there is something visible
 124                 text->GetVisibleRow(owner.owner(), y, 0, row, y + first);
 125         }
 126 }
 127
 128
 129 /* draws the screen, starting with textposition y. uses as much already
 130 * printed pixels as possible */
 131 void LyXScreen::Draw(unsigned long y)
 132 {
 133         if (cursor_visible) HideCursor();
 134
 135         unsigned long old_first = first;
 136         first = y;
 137
 138         // is any optimiziation possible?
 139         if ((y - old_first) < owner.height()
 140             && (old_first - y) < owner.height()) {
 141                 if (first < old_first) {
 142                         DrawFromTo(0, old_first - first);
 143                         XCopyArea (fl_display,
 144                                    owner.getWin(),
 145                                    owner.getWin(),
 146                                    gc_copy,
 147                                    owner.xpos(),
 148                                    owner.ypos(),
 149                                    owner.workWidth(),
 150                                    owner.height() - old_first + first,
 151                                    owner.xpos(),
 152                                    owner.ypos() + old_first - first
 153                                 );
 154                         // expose the area drawn
 155                         expose(0, 0,
 156                                owner.workWidth(),
 157                                old_first - first);
 158                 } else  {
 159                         DrawFromTo(
 160                                 owner.height() + old_first - first,
 161                                    owner.height());
 162                         XCopyArea (fl_display,
 163                                    owner.getWin(),
 164                                    owner.getWin(),
 165                                    gc_copy,
 166                                    owner.xpos(),
 167                                    owner.ypos() + first - old_first,
 168                                    owner.workWidth(),
 169                                    owner.height() + old_first - first,
 170                                    owner.xpos(),
 171                                    owner.ypos());
 172                         // expose the area drawn
 173                         expose(0, owner.height() + old_first - first,
 174                                owner.workWidth(), first - old_first);
 175                 }
 176         } else {
 177                 // make a dumb new-draw
 178                 DrawFromTo(0, owner.height());
 179                 expose(0, 0, owner.workWidth(), owner.height());
 180         }
 181 }
 182
 183
 184 void LyXScreen::ShowCursor()
 185 {
 186         if (!cursor_visible) {
 187                 Cursor_Shape shape = BAR_SHAPE;
 188                 if (text->real_current_font.language() !=
 189                     owner.owner()->buffer()->params.language_info
 190                     || text->real_current_font.isVisibleRightToLeft()
 191                     != owner.owner()->buffer()->params.language_info->RightToLeft())
 192                         shape = (text->real_current_font.isVisibleRightToLeft())
 193                                 ? REVERSED_L_SHAPE : L_SHAPE;
 194                 ShowManualCursor(text->cursor.x(), text->cursor.y(),
 195                                  lyxfont::maxAscent(text->real_current_font),
 196                                  lyxfont::maxDescent(text->real_current_font),
 197                                  shape);
 198         }
 199 }
 200
 201
 202 /* returns true if first has changed, otherwise false */
 203 bool LyXScreen::FitManualCursor(long /*x*/, long y, int asc, int desc)
 204 {
 205         long newtop = first;
 206
 207         if (y + desc - first >= owner.height())
 208                 newtop = y - 3 * owner.height() / 4;  // the scroll region must be so big!!
 209         else if (y - asc < long(first)
 210                 && first > 0) {
 211                 newtop = y - owner.height() / 4;
 212         }
 213
 214         newtop = max(newtop, 0L); // can newtop ever be < 0? (Lgb)
 215
 216         if (newtop != long(first)) {
 217                 Draw(newtop);
 218                 first = newtop;
 219                 return true;
 220         }
 221         return false;
 222 }
 223
 224
 225 void LyXScreen::ShowManualCursor(long x, long y, int asc, int desc,
 226                                   Cursor_Shape shape)
 227 {
 228         unsigned long y1 = max(y - first - asc, 0UL);
 229         typedef unsigned long ulong;
 230
 231         unsigned long y2 = min(y - first + desc, ulong(owner.height()));
 232
 233         // Secure against very strange situations
 234         y2 = max(y2, y1);
 235
 236         if (cursor_pixmap){
 237                 XFreePixmap(fl_display, cursor_pixmap);
 238                 cursor_pixmap = 0;
 239         }
 240
 241         if (y2 > 0 && y1 < owner.height()) {
 242                 cursor_pixmap_h = y2 - y1 + 1;
 243                 cursor_pixmap_y = y1;
 244
 245                 switch(shape) {
 246                 case BAR_SHAPE:
 247                         cursor_pixmap_w = 1;
 248                         cursor_pixmap_x = x;
 249                         break;
 250                 case L_SHAPE:
 251                         cursor_pixmap_w = cursor_pixmap_h/3;
 252                         cursor_pixmap_x = x;
 253                         break;
 254                 case REVERSED_L_SHAPE:
 255                         cursor_pixmap_w = cursor_pixmap_h/3;
 256                         cursor_pixmap_x = x - cursor_pixmap_w + 1;
 257                         break;
 258                 }
 259
 260                 cursor_pixmap =
 261                         XCreatePixmap (fl_display,
 262                                        fl_root,
 263                                        cursor_pixmap_w,
 264                                        cursor_pixmap_h,
 265                                        fl_get_visual_depth());
 266                 XCopyArea (fl_display,
 267                            owner.getWin(),
 268                            cursor_pixmap,
 269                            gc_copy,
 270                            owner.xpos() + cursor_pixmap_x,
 271                            owner.ypos() + cursor_pixmap_y,
 272                            cursor_pixmap_w,
 273                            cursor_pixmap_h,
 274                            0, 0);
 275                 XDrawLine(fl_display,
 276                           owner.getWin(),
 277                           gc_copy,
 278                           x + owner.xpos(),
 279                           y1 + owner.ypos(),
 280                           x + owner.xpos(),
 281                           y2 + owner.ypos());
 282                 switch(shape) {
 283                 case BAR_SHAPE:
 284                         break;
 285                 case L_SHAPE:
 286                 case REVERSED_L_SHAPE:
 287                         int rectangle_h = (cursor_pixmap_h+10)/20;
 288                         XFillRectangle(fl_display,
 289                                        owner.getWin(),
 290                                        gc_copy,
 291                                        cursor_pixmap_x + owner.xpos(),
 292                                        y2 - rectangle_h + 1 + owner.ypos(),
 293                                        cursor_pixmap_w - 1, rectangle_h);
 294                         break;
 295                 }
 296
 297         }
 298         cursor_visible = true;
 299 }
 300
 301
 302 void LyXScreen::HideCursor()
 303 {
 304         if (!cursor_visible) return;
 305
 306         if (cursor_pixmap){
 307                 XCopyArea (fl_display,
 308                            cursor_pixmap,
 309                            owner.getWin(),
 310                            gc_copy,
 311                            0, 0,
 312                            cursor_pixmap_w, cursor_pixmap_h,
 313                            cursor_pixmap_x + owner.xpos(),
 314                            cursor_pixmap_y + owner.ypos());
 315         }
 316         cursor_visible = false;
 317 }
 318
 319
 320 void LyXScreen::CursorToggle()
 321 {
 322         if (cursor_visible)
 323                 HideCursor();
 324         else
 325                 ShowCursor();
 326 }
 327
 328
 329 /* returns a new top so that the cursor is visible */
 330 unsigned long LyXScreen::TopCursorVisible()
 331 {
 332         long newtop = first;
 333
 334         if (text->cursor.y()
 335             - text->cursor.row()->baseline()
 336             + text->cursor.row()->height()
 337             - first >= owner.height()) {
 338                 if (text->cursor.row()->height() < owner.height()
 339                     && text->cursor.row()->height() > owner.height() / 4)
 340                         newtop = text->cursor.y()
 341                                 + text->cursor.row()->height()
 342                                 - text->cursor.row()->baseline() - owner.height();
 343                 else
 344                         newtop = text->cursor.y()
 345                                 - 3 * owner.height() / 4;   /* the scroll region must be so big!! */
 346         } else if (text->cursor.y() - text->cursor.row()->baseline() < first
 347                    && first > 0) {
 348                 if (text->cursor.row()->height() < owner.height()
 349                     && text->cursor.row()->height() > owner.height() / 4)
 350                         newtop = text->cursor.y() - text->cursor.row()->baseline();
 351                 else {
 352                         newtop = text->cursor.y() - owner.height() / 4;
 353                         newtop = min(newtop, long(first));
 354                 }
 355         }
 356
 357         newtop = max(newtop, 0L);
 358
 359         return newtop;
 360 }
 361
 362
 363 /* scrolls the screen so that the cursor is visible, if necessary.
 364 * returns true if a change was made, otherwise false */
 365 bool LyXScreen::FitCursor()
 366 {
 367         // Is a change necessary?
 368         unsigned long newtop = TopCursorVisible();
 369         bool result = (newtop != first);
 370         if (result)
 371                 Draw(newtop);
 372         return result;
 373 }
 374
 375
 376 void LyXScreen::Update()
 377 {
 378         switch(text->status) {
 379         case LyXText::NEED_MORE_REFRESH:
 380         {
 381                 long y = max(text->refresh_y - long(first), 0L);
 382
 383                 DrawFromTo(y, owner.height());
 384                 text->refresh_y = 0;
 385                 text->status = LyXText::UNCHANGED;
 386                 expose(0, y,
 387                        owner.workWidth(), owner.height() - y);
 388         }
 389         break;
 390         case LyXText::NEED_VERY_LITTLE_REFRESH:
 391         {
 392                 // ok I will update the current cursor row
 393                 DrawOneRow(text->refresh_row, text->refresh_y);
 394                 text->status = LyXText::UNCHANGED;
 395                 expose(0, text->refresh_y - first,
 396                        owner.workWidth(), text->refresh_row->height());
 397         }
 398         break;
 399         case LyXText::UNCHANGED:
 400                 // Nothing needs done
 401                 break;
 402         }
 403 }
 404
 405
 406 void LyXScreen::ToggleSelection(bool kill_selection)
 407 {
 408         // only if there is a selection
 409         if (!text->selection) return;
 410
 411         long bottom = min(max(text->sel_end_cursor.y()
 412                               - text->sel_end_cursor.row()->baseline()
 413                               + text->sel_end_cursor.row()->height(), first),
 414                           first + owner.height());
 415         long top = min(max(text->sel_start_cursor.y()
 416                            - text->sel_start_cursor.row()->baseline(), first),
 417                        first + owner.height());
 418
 419         if (kill_selection)
 420                 text->selection = 0;
 421         DrawFromTo(top - first, bottom - first);
 422         expose(0, top - first,
 423                owner.workWidth(),
 424                bottom - first - (top - first));
 425 }
 426
 427
 428 void LyXScreen::ToggleToggle()
 429 {
 430         if (text->toggle_cursor.par() == text->toggle_end_cursor.par()
 431             && text->toggle_cursor.pos() == text->toggle_end_cursor.pos())
 432                 return;
 433
 434         long top = text->toggle_cursor.y()
 435                 - text->toggle_cursor.row()->baseline();
 436         long bottom = text->toggle_end_cursor.y()
 437                 - text->toggle_end_cursor.row()->baseline()
 438                 + text->toggle_end_cursor.row()->height();
 439
 440         typedef unsigned long ulong;
 441
 442         bottom = min(max(ulong(bottom), first), first + owner.height());
 443         top = min(max(ulong(top), first), first + owner.height());
 444
 445         DrawFromTo(top - first, bottom - first);
 446         expose(0, top - first, owner.workWidth(),
 447                bottom - first - (top - first));
 448 }