Pileus Git - ~andy/gtk/blob - gtk/gtktextdisplay.c

   1 /* gtktextdisplay.c - display layed-out text
   2  *
   3  * Copyright (c) 1992-1994 The Regents of the University of California.
   4  * Copyright (c) 1994-1997 Sun Microsystems, Inc.
   5  * Copyright (c) 2000 Red Hat, Inc.
   6  * Tk->Gtk port by Havoc Pennington
   7  *
   8  *
   9  * This software is copyrighted by the Regents of the University of
  10  * California, Sun Microsystems, Inc., and other parties.  The
  11  * following terms apply to all files associated with the software
  12  * unless explicitly disclaimed in individual files.
  13  *
  14  * The authors hereby grant permission to use, copy, modify,
  15  * distribute, and license this software and its documentation for any
  16  * purpose, provided that existing copyright notices are retained in
  17  * all copies and that this notice is included verbatim in any
  18  * distributions. No written agreement, license, or royalty fee is
  19  * required for any of the authorized uses.  Modifications to this
  20  * software may be copyrighted by their authors and need not follow
  21  * the licensing terms described here, provided that the new terms are
  22  * clearly indicated on the first page of each file where they apply.
  23  *
  24  * IN NO EVENT SHALL THE AUTHORS OR DISTRIBUTORS BE LIABLE TO ANY
  25  * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL
  26  * DAMAGES ARISING OUT OF THE USE OF THIS SOFTWARE, ITS DOCUMENTATION,
  27  * OR ANY DERIVATIVES THEREOF, EVEN IF THE AUTHORS HAVE BEEN ADVISED
  28  * OF THE POSSIBILITY OF SUCH DAMAGE.
  29  *
  30  * THE AUTHORS AND DISTRIBUTORS SPECIFICALLY DISCLAIM ANY WARRANTIES,
  31  * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  32  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, AND
  33  * NON-INFRINGEMENT.  THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS,
  34  * AND THE AUTHORS AND DISTRIBUTORS HAVE NO OBLIGATION TO PROVIDE
  35  * MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  36  *
  37  * GOVERNMENT USE: If you are acquiring this software on behalf of the
  38  * U.S. government, the Government shall have only "Restricted Rights"
  39  * in the software and related documentation as defined in the Federal
  40  * Acquisition Regulations (FARs) in Clause 52.227.19 (c) (2).  If you
  41  * are acquiring the software on behalf of the Department of Defense,
  42  * the software shall be classified as "Commercial Computer Software"
  43  * and the Government shall have only "Restricted Rights" as defined
  44  * in Clause 252.227-7013 (c) (1) of DFARs.  Notwithstanding the
  45  * foregoing, the authors grant the U.S. Government and others acting
  46  * in its behalf permission to use and distribute the software in
  47  * accordance with the terms specified in this license.
  48  *
  49  */
  50
  51 #include "gtktextdisplay.h"
  52 #include "gtktextiterprivate.h"
  53 #include <pango/pangox.h>
  54 #include "x11/gdkx.h"
  55
  56 typedef struct _GtkTextRenderState GtkTextRenderState;
  57
  58 struct _GtkTextRenderState
  59 {
  60   GtkWidget *widget;
  61
  62   GtkTextAppearance *last_appearance;
  63   GdkGC *fg_gc;
  64   GdkGC *bg_gc;
  65   GdkRectangle clip_rect;
  66 };
  67
  68 static void       get_item_properties (PangoItem           *item,
  69                                        GtkTextAppearance  **appearance);
  70 static GdkRegion *get_selected_clip   (GtkTextRenderState  *render_state,
  71                                        PangoLayout         *layout,
  72                                        PangoLayoutLine     *line,
  73                                        int                  x,
  74                                        int                  y,
  75                                        int                  height,
  76                                        int                  start_index,
  77                                        int                  end_index);
  78
  79 static GtkTextRenderState *
  80 gtk_text_render_state_new (GtkWidget    *widget,
  81                            GdkDrawable  *drawable,
  82                            GdkRectangle *clip_rect)
  83 {
  84   GtkTextRenderState *state = g_new0 (GtkTextRenderState, 1);
  85
  86   state->widget = widget;
  87   state->fg_gc = gdk_gc_new (drawable);
  88   state->bg_gc = gdk_gc_new (drawable);
  89   state->clip_rect = *clip_rect;
  90
  91   return state;
  92 }
  93
  94 static void
  95 gtk_text_render_state_destroy (GtkTextRenderState *state)
  96 {
  97   gdk_gc_unref (state->fg_gc);
  98   gdk_gc_unref (state->bg_gc);
  99
 100   g_free (state);
 101 }
 102
 103 static void
 104 gtk_text_render_state_set_color (GtkTextRenderState *state,
 105                                  GdkGC              *gc,
 106                                  GdkColor           *color)
 107 {
 108   gdk_colormap_alloc_color (gtk_widget_get_colormap (state->widget), color, FALSE, TRUE);
 109   gdk_gc_set_foreground (gc, color);
 110 }
 111
 112 static void
 113 gtk_text_render_state_update (GtkTextRenderState *state,
 114                               GtkTextAppearance  *new_appearance)
 115 {
 116   if (!state->last_appearance ||
 117       !gdk_color_equal (&new_appearance->fg_color, &state->last_appearance->fg_color))
 118     gtk_text_render_state_set_color (state, state->fg_gc, &new_appearance->fg_color);
 119
 120   if (!state->last_appearance ||
 121       new_appearance->fg_stipple != state->last_appearance->fg_stipple)
 122     {
 123       if (new_appearance->fg_stipple)
 124         {
 125           gdk_gc_set_fill(state->fg_gc, GDK_STIPPLED);
 126           gdk_gc_set_stipple(state->fg_gc, new_appearance->fg_stipple);
 127         }
 128       else
 129         {
 130           gdk_gc_set_fill(state->fg_gc, GDK_SOLID);
 131         }
 132     }
 133
 134   if (new_appearance->draw_bg)
 135     {
 136       if (!state->last_appearance ||
 137           !gdk_color_equal (&new_appearance->bg_color, &state->last_appearance->bg_color))
 138         gtk_text_render_state_set_color (state, state->bg_gc, &new_appearance->bg_color);
 139
 140       if (!state->last_appearance ||
 141           new_appearance->bg_stipple != state->last_appearance->bg_stipple)
 142         {
 143           if (new_appearance->bg_stipple)
 144             {
 145               gdk_gc_set_fill(state->bg_gc, GDK_STIPPLED);
 146               gdk_gc_set_stipple(state->bg_gc, new_appearance->bg_stipple);
 147             }
 148           else
 149             {
 150               gdk_gc_set_fill(state->bg_gc, GDK_SOLID);
 151             }
 152         }
 153     }
 154
 155   state->last_appearance = new_appearance;
 156 }
 157
 158 static void
 159 render_layout_line (GdkDrawable        *drawable,
 160                     GtkTextRenderState *render_state,
 161                     PangoLayoutLine    *line,
 162                     int                 x,
 163                     int                 y,
 164                     gboolean            selected)
 165 {
 166   GSList *tmp_list = line->runs;
 167   PangoRectangle overall_rect;
 168   PangoRectangle logical_rect;
 169   PangoRectangle ink_rect;
 170
 171   gint x_off = 0;
 172
 173   pango_layout_line_get_extents (line, NULL, &overall_rect);
 174
 175   while (tmp_list)
 176     {
 177       PangoLayoutRun *run = tmp_list->data;
 178       GtkTextAppearance *appearance;
 179
 180       tmp_list = tmp_list->next;
 181
 182       get_item_properties (run->item, &appearance);
 183
 184       if (appearance)           /* A text segment */
 185         {
 186           GdkGC *fg_gc;
 187
 188           if (selected)
 189             {
 190               fg_gc = render_state->widget->style->fg_gc[GTK_STATE_SELECTED];
 191             }
 192           else
 193             {
 194               gtk_text_render_state_update (render_state, appearance);
 195
 196               fg_gc = render_state->fg_gc;
 197             }
 198
 199           if (appearance->underline == PANGO_UNDERLINE_NONE && !appearance->overstrike)
 200             pango_glyph_string_extents (run->glyphs, run->item->analysis.font,
 201                                         NULL, &logical_rect);
 202           else
 203             pango_glyph_string_extents (run->glyphs, run->item->analysis.font,
 204                                         &ink_rect, &logical_rect);
 205
 206           if (appearance->draw_bg && !selected)
 207             gdk_draw_rectangle (drawable, render_state->bg_gc, TRUE,
 208                                 x + (x_off + logical_rect.x) / PANGO_SCALE,
 209                                 y + logical_rect.y / PANGO_SCALE,
 210                                 logical_rect.width / PANGO_SCALE,
 211                                 logical_rect.height / PANGO_SCALE);
 212
 213           gdk_draw_glyphs (drawable, fg_gc,
 214                            run->item->analysis.font,
 215                            x + x_off / PANGO_SCALE, y, run->glyphs);
 216
 217           switch (appearance->underline)
 218             {
 219             case PANGO_UNDERLINE_NONE:
 220               break;
 221             case PANGO_UNDERLINE_DOUBLE:
 222               gdk_draw_line (drawable, fg_gc,
 223                          x + (x_off + ink_rect.x) / PANGO_SCALE - 1, y + 4,
 224                          x + (x_off + ink_rect.x + ink_rect.width) / PANGO_SCALE, y + 4);
 225               /* Fall through */
 226             case PANGO_UNDERLINE_SINGLE:
 227               gdk_draw_line (drawable, fg_gc,
 228                          x + (x_off + ink_rect.x) / PANGO_SCALE - 1, y + 2,
 229                          x + (x_off + ink_rect.x + ink_rect.width) / PANGO_SCALE, y + 2);
 230               break;
 231             case PANGO_UNDERLINE_LOW:
 232               gdk_draw_line (drawable, fg_gc,
 233                          x + (x_off + ink_rect.x) / PANGO_SCALE - 1, y + (ink_rect.y + ink_rect.height) / PANGO_SCALE + 2,
 234                          x + (x_off + ink_rect.x + ink_rect.width) / PANGO_SCALE, y + (ink_rect.y + ink_rect.height) / PANGO_SCALE + 2);
 235               break;
 236             }
 237
 238           if (appearance->overstrike)
 239             {
 240               gint overstrike_y = y + (0.3 * logical_rect.y) / PANGO_SCALE;
 241               gdk_draw_line (drawable, fg_gc,
 242                              x + (x_off + ink_rect.x) / PANGO_SCALE - 1, overstrike_y,
 243                              x + (x_off + ink_rect.x + ink_rect.width) / PANGO_SCALE, overstrike_y);
 244             }
 245
 246           x_off += logical_rect.width;
 247         }
 248     }
 249 }
 250
 251 static void
 252 render_para (GdkDrawable        *drawable,
 253              GtkTextRenderState *render_state,
 254              GtkTextLineDisplay *line_display,
 255              int                 x,
 256              int                 y,
 257              int                 selection_start_index,
 258              int                 selection_end_index)
 259 {
 260   PangoRectangle logical_rect;
 261   GSList *tmp_list;
 262   PangoAlignment align;
 263   PangoLayout *layout = line_display->layout;
 264   int indent;
 265   int total_width;
 266   int y_offset = 0;
 267   int byte_offset = 0;
 268
 269   gboolean first = TRUE;
 270
 271   indent = pango_layout_get_indent (layout);
 272   total_width = pango_layout_get_width (layout);
 273   align = pango_layout_get_alignment (layout);
 274
 275   if (total_width < 0)
 276     total_width = line_display->total_width * PANGO_SCALE;
 277
 278   tmp_list = pango_layout_get_lines (layout);
 279   while (tmp_list)
 280     {
 281       PangoLayoutLine *line = tmp_list->data;
 282       int x_offset;
 283       int selection_y, selection_height;
 284
 285       pango_layout_line_get_extents (line, NULL, &logical_rect);
 286
 287       x_offset = line_display->left_margin * PANGO_SCALE;
 288
 289       switch (align)
 290         {
 291         case PANGO_ALIGN_RIGHT:
 292           x_offset += total_width - logical_rect.width;
 293           break;
 294         case PANGO_ALIGN_CENTER:
 295           x_offset += (total_width - logical_rect.width) / 2;
 296           break;
 297         default:
 298           break;
 299         }
 300
 301       if (first)
 302         {
 303           if (indent > 0)
 304             {
 305               if (align == PANGO_ALIGN_LEFT)
 306                 x_offset += indent;
 307               else
 308                 x_offset -= indent;
 309             }
 310         }
 311       else
 312         {
 313           if (indent < 0)
 314             {
 315               if (align == PANGO_ALIGN_LEFT)
 316                 x_offset -= indent;
 317               else
 318                 x_offset += indent;
 319             }
 320         }
 321
 322       selection_y = y + y_offset / PANGO_SCALE;
 323       selection_height = logical_rect.height / PANGO_SCALE;
 324
 325       if (first)
 326         {
 327           selection_y -= line_display->top_margin;
 328           selection_height += line_display->top_margin;
 329         }
 330       if (!tmp_list->next)
 331         selection_height += line_display->bottom_margin;
 332
 333       first = FALSE;
 334
 335       if (selection_start_index < byte_offset &&
 336           selection_end_index > line->length + byte_offset) /* All selected */
 337         {
 338           gdk_draw_rectangle (drawable,
 339                               render_state->widget->style->bg_gc[GTK_STATE_SELECTED],
 340                               TRUE,
 341                               x + line_display->left_margin, selection_y,
 342                               total_width / PANGO_SCALE, selection_height);
 343           render_layout_line (drawable, render_state,
 344                               line, x + x_offset / PANGO_SCALE, y + (y_offset - logical_rect.y) / PANGO_SCALE,
 345                               TRUE);
 346         }
 347       else
 348         {
 349           render_layout_line (drawable, render_state,
 350                               line, x + x_offset / PANGO_SCALE, y + (y_offset - logical_rect.y) / PANGO_SCALE,
 351                               FALSE);
 352
 353           if (selection_start_index < byte_offset + line->length &&
 354               selection_end_index > byte_offset) /* Some selected */
 355             {
 356               GdkRegion *clip_region = get_selected_clip (render_state, layout, line,
 357                                                           x + line_display->x_offset,
 358                                                           selection_y, selection_height,
 359                                                           selection_start_index, selection_end_index);
 360
 361               gdk_gc_set_clip_region (render_state->widget->style->fg_gc [GTK_STATE_SELECTED], clip_region);
 362               gdk_gc_set_clip_region (render_state->widget->style->bg_gc [GTK_STATE_SELECTED], clip_region);
 363
 364               gdk_draw_rectangle (drawable,
 365                                   render_state->widget->style->bg_gc[GTK_STATE_SELECTED],
 366                                   TRUE,
 367                                   x + x_offset / PANGO_SCALE, selection_y,
 368                                   logical_rect.width / PANGO_SCALE,
 369                                   selection_height);
 370
 371               render_layout_line (drawable, render_state,
 372                                   line, x + x_offset / PANGO_SCALE, y + (y_offset - logical_rect.y) / PANGO_SCALE,
 373                                   TRUE);
 374
 375               gdk_gc_set_clip_region (render_state->widget->style->fg_gc [GTK_STATE_SELECTED], NULL);
 376               gdk_gc_set_clip_region (render_state->widget->style->bg_gc [GTK_STATE_SELECTED], NULL);
 377
 378               gdk_region_destroy (clip_region);
 379
 380               /* Paint in the ends of the line */
 381               if (x_offset > line_display->left_margin * PANGO_SCALE &&
 382                   ((line_display->direction == GTK_TEXT_DIR_LTR && selection_start_index < byte_offset) ||
 383                    (line_display->direction == GTK_TEXT_DIR_RTL && selection_end_index > byte_offset + line->length)))
 384                 {
 385                   gdk_draw_rectangle (drawable,
 386                                       render_state->widget->style->bg_gc[GTK_STATE_SELECTED],
 387                                       TRUE,
 388                                       x + line_display->left_margin, selection_y,
 389                                       x + x_offset / PANGO_SCALE - line_display->left_margin,
 390                                       selection_height);
 391                 }
 392
 393               if (x_offset + logical_rect.width < line_display->left_margin * PANGO_SCALE + total_width &&
 394                   ((line_display->direction == GTK_TEXT_DIR_LTR && selection_end_index > byte_offset + line->length) ||
 395                    (line_display->direction == GTK_TEXT_DIR_RTL && selection_start_index < byte_offset)))
 396                 {
 397
 398
 399                   gdk_draw_rectangle (drawable,
 400                                       render_state->widget->style->bg_gc[GTK_STATE_SELECTED],
 401                                       TRUE,
 402                                       x + (x_offset + logical_rect.width) / PANGO_SCALE,
 403                                       selection_y,
 404                                       x + (line_display->left_margin * PANGO_SCALE + total_width - x_offset - logical_rect.width) / PANGO_SCALE,
 405                                       selection_height);
 406                 }
 407             }
 408         }
 409
 410       byte_offset += line->length;
 411       y_offset += logical_rect.height;
 412       tmp_list = tmp_list->next;
 413     }
 414 }
 415
 416 static GdkRegion *
 417 get_selected_clip (GtkTextRenderState *render_state,
 418                    PangoLayout        *layout,
 419                    PangoLayoutLine    *line,
 420                    int                 x,
 421                    int                 y,
 422                    int                 height,
 423                    int                 start_index,
 424                    int                 end_index)
 425 {
 426   gint *ranges;
 427   gint n_ranges, i;
 428   GdkRegion *clip_region = gdk_region_new ();
 429   GdkRegion *tmp_region;
 430   PangoRectangle logical_rect;
 431
 432   pango_layout_line_get_extents (line, NULL, &logical_rect);
 433   pango_layout_line_get_x_ranges (line, start_index, end_index, &ranges, &n_ranges);
 434
 435   for (i=0; i < n_ranges; i++)
 436     {
 437       GdkRectangle rect;
 438
 439       rect.x = x + ranges[2*i] / PANGO_SCALE;
 440       rect.y = y;
 441       rect.width = (ranges[2*i + 1] - ranges[2*i]) / PANGO_SCALE;
 442       rect.height = height;
 443
 444       gdk_region_union_with_rect (clip_region, &rect);
 445     }
 446
 447   tmp_region = gdk_region_rectangle (&render_state->clip_rect);
 448   gdk_region_intersect (clip_region, tmp_region);
 449   gdk_region_destroy (tmp_region);
 450
 451   g_free (ranges);
 452   return clip_region;
 453 }
 454
 455 static void
 456 get_item_properties (PangoItem          *item,
 457                      GtkTextAppearance **appearance)
 458 {
 459   GSList *tmp_list = item->extra_attrs;
 460
 461   *appearance = NULL;
 462
 463   while (tmp_list)
 464     {
 465       PangoAttribute *attr = tmp_list->data;
 466
 467       if (attr->klass->type == gtk_text_attr_appearance_type)
 468         {
 469           *appearance = &((GtkTextAttrAppearance *)attr)->appearance;
 470           return;
 471         }
 472     }
 473 }
 474
 475 void
 476 gtk_text_layout_draw (GtkTextLayout *layout,
 477                       GtkWidget *widget,
 478                       GdkDrawable *drawable,
 479                       /* Location of the layout
 480                          in buffer coordinates */
 481                       gint x_offset,
 482                       gint y_offset,
 483                       /* Region of the layout to
 484                          render */
 485                       gint x,
 486                       gint y,
 487                       gint width,
 488                       gint height)
 489 {
 490   GdkRectangle clip;
 491   gint current_y;
 492   GSList *line_list;
 493   GSList *tmp_list;
 494   GSList *cursor_list;
 495   GtkTextRenderState *render_state;
 496   GtkTextIter selection_start, selection_end;
 497   gboolean have_selection = FALSE;
 498
 499   g_return_if_fail (GTK_IS_TEXT_LAYOUT (layout));
 500   g_return_if_fail (layout->default_style != NULL);
 501   g_return_if_fail (layout->buffer != NULL);
 502   g_return_if_fail (drawable != NULL);
 503   g_return_if_fail (x_offset >= 0);
 504   g_return_if_fail (y_offset >= 0);
 505   g_return_if_fail (width >= 0);
 506   g_return_if_fail (height >= 0);
 507
 508   if (width == 0 || height == 0)
 509     return;
 510
 511   line_list =  gtk_text_layout_get_lines (layout, y + y_offset, y + y_offset + height, &current_y);
 512   current_y -= y_offset;
 513
 514   if (line_list == NULL)
 515     return; /* nothing on the screen */
 516
 517   clip.x = x;
 518   clip.y = y;
 519   clip.width = width;
 520   clip.height = height;
 521
 522   render_state = gtk_text_render_state_new (widget, drawable, &clip);
 523
 524   gdk_gc_set_clip_rectangle (render_state->fg_gc, &clip);
 525   gdk_gc_set_clip_rectangle (render_state->bg_gc, &clip);
 526
 527   gtk_text_layout_wrap_loop_start (layout);
 528
 529   if (gtk_text_buffer_get_selection_bounds (layout->buffer,
 530                                             &selection_start,
 531                                             &selection_end))
 532     have_selection = TRUE;
 533
 534   tmp_list = line_list;
 535   while (tmp_list != NULL)
 536     {
 537       GtkTextLineDisplay *line_display;
 538       gint selection_start_index = -1;
 539       gint selection_end_index = -1;
 540
 541       GtkTextLine *line = tmp_list->data;
 542
 543       line_display = gtk_text_layout_get_line_display (layout, line, FALSE);
 544
 545       if (have_selection)
 546         {
 547           GtkTextIter line_start, line_end;
 548           gint byte_count = gtk_text_line_byte_count (line);
 549
 550           gtk_text_btree_get_iter_at_line (layout->buffer->tree, &line_start,
 551                                            line, 0);
 552           gtk_text_btree_get_iter_at_line (layout->buffer->tree, &line_end,
 553                                            line, byte_count - 1);
 554
 555           if (gtk_text_iter_compare (&selection_start, &line_end) < 0 &&
 556               gtk_text_iter_compare (&selection_end, &line_start) > 0)
 557             {
 558               if (gtk_text_iter_compare (&selection_start, &line_start) >= 0)
 559                 selection_start_index = gtk_text_iter_get_line_byte (&selection_start);
 560               else
 561                 selection_start_index = -1;
 562
 563               if (gtk_text_iter_compare (&selection_end, &line_end) <= 0)
 564                 selection_end_index = gtk_text_iter_get_line_byte (&selection_end);
 565               else
 566                 selection_end_index = byte_count;
 567             }
 568         }
 569
 570       render_para (drawable, render_state, line_display,
 571                    - x_offset,
 572                    current_y + line_display->top_margin,
 573                    selection_start_index, selection_end_index);
 574
 575
 576       /* We paint the cursors last, because they overlap another chunk
 577          and need to appear on top. */
 578
 579       cursor_list = line_display->cursors;
 580       while (cursor_list)
 581         {
 582           GtkTextCursorDisplay *cursor = cursor_list->data;
 583           GdkGC *gc;
 584
 585           if (cursor->is_strong)
 586             gc = widget->style->bg_gc[GTK_STATE_SELECTED];
 587           else
 588             gc = widget->style->fg_gc[GTK_STATE_NORMAL];
 589
 590           gdk_draw_line (drawable, gc,
 591                          line_display->x_offset + cursor->x,
 592                          current_y + line_display->top_margin + cursor->y,
 593                          line_display->x_offset + cursor->x,
 594                          current_y + line_display->top_margin + cursor->y + cursor->height);
 595
 596           cursor_list = cursor_list->next;
 597         }
 598
 599       current_y += line_display->height;
 600       gtk_text_layout_free_line_display (layout, line_display);
 601
 602       tmp_list = g_slist_next (tmp_list);
 603     }
 604
 605   gtk_text_layout_wrap_loop_end (layout);
 606   gtk_text_render_state_destroy (render_state);
 607
 608   g_slist_free (line_list);
 609 }