gtktextutil.c 15.5 KB
Newer Older
Cody Russell's avatar
Cody Russell committed
1
/* GTK - The GIMP Toolkit
2 3 4 5 6 7 8 9 10 11 12 13 14
 * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
Javier Jardón's avatar
Javier Jardón committed
15
 * License along with this library. If not, see <http://www.gnu.org/licenses/>.
16 17 18 19 20 21 22 23 24
 */

/*
 * Modified by the GTK+ Team and others 1997-2001.  See the AUTHORS
 * file for a list of people on the GTK+ Team.  See the ChangeLog
 * files for a list of changes.  These files are distributed with
 * GTK+ at ftp://ftp.gtk.org/pub/gtk/. 
 */

25
#include "config.h"
26

27
#include "gtktextview.h"
28
#include "gtktextutil.h"
29 30 31 32 33

#define GTK_TEXT_USE_INTERNAL_UNSUPPORTED_API

#include "gtktextdisplay.h"
#include "gtktextbuffer.h"
34
#include "gtkmenuitem.h"
35
#include "gtkintl.h"
36

37
#define DRAG_ICON_MAX_WIDTH 250
38
#define DRAG_ICON_MAX_HEIGHT 250
39 40 41
#define DRAG_ICON_MAX_LINES 7
#define ELLIPSIS_CHARACTER "\xe2\x80\xa6"

42 43 44 45 46 47 48 49 50 51 52 53 54 55
typedef struct _GtkUnicodeMenuEntry GtkUnicodeMenuEntry;
typedef struct _GtkTextUtilCallbackInfo GtkTextUtilCallbackInfo;

struct _GtkUnicodeMenuEntry {
  const char *label;
  gunichar ch;
};

struct _GtkTextUtilCallbackInfo
{
  GtkTextUtilCharChosenFunc func;
  gpointer data;
};

56
static const GtkUnicodeMenuEntry bidi_menu_entries[] = {
57 58 59 60 61 62 63 64
  { N_("LRM _Left-to-right mark"), 0x200E },
  { N_("RLM _Right-to-left mark"), 0x200F },
  { N_("LRE Left-to-right _embedding"), 0x202A },
  { N_("RLE Right-to-left e_mbedding"), 0x202B },
  { N_("LRO Left-to-right _override"), 0x202D },
  { N_("RLO Right-to-left o_verride"), 0x202E },
  { N_("PDF _Pop directional formatting"), 0x202C },
  { N_("ZWS _Zero width space"), 0x200B },
65
  { N_("ZWJ Zero width _joiner"), 0x200D },
66 67 68
  { N_("ZWNJ Zero width _non-joiner"), 0x200C }
};

69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88
static GtkTextUtilCallbackInfo *
callback_info_new (GtkTextUtilCharChosenFunc  func,
                   gpointer                   data)
{
  GtkTextUtilCallbackInfo *info;

  info = g_slice_new (GtkTextUtilCallbackInfo);

  info->func = func;
  info->data = data;

  return info;
}

static void
callback_info_free (GtkTextUtilCallbackInfo *info)
{
  g_slice_free (GtkTextUtilCallbackInfo, info);
}

89 90 91 92 93 94 95 96 97 98 99 100 101 102 103
static void
activate_cb (GtkWidget *menu_item,
             gpointer   data)
{
  GtkUnicodeMenuEntry *entry;
  GtkTextUtilCallbackInfo *info = data;
  char buf[7];
  
  entry = g_object_get_data (G_OBJECT (menu_item), "gtk-unicode-menu-entry");

  buf[g_unichar_to_utf8 (entry->ch, buf)] = '\0';
  
  (* info->func) (buf, info->data);
}

104
/*
105 106 107 108 109 110 111 112 113 114 115 116 117
 * _gtk_text_util_append_special_char_menuitems
 * @menushell: a #GtkMenuShell
 * @callback:  call this when an item is chosen
 * @data: data for callback
 * 
 * Add menuitems for various bidi control characters  to a menu;
 * the menuitems, when selected, will call the given function
 * with the chosen character.
 *
 * This function is private/internal in GTK 2.0, the functionality may
 * become public sometime, but it probably needs more thought first.
 * e.g. maybe there should be a way to just get the list of items,
 * instead of requiring the menu items to be created.
118
 */
119 120 121 122 123 124
void
_gtk_text_util_append_special_char_menuitems (GtkMenuShell              *menushell,
                                              GtkTextUtilCharChosenFunc  func,
                                              gpointer                   data)
{
  int i;
125

126 127 128 129 130
  for (i = 0; i < G_N_ELEMENTS (bidi_menu_entries); i++)
    {
      GtkWidget *menuitem;
      GtkTextUtilCallbackInfo *info;

131 132
      info = callback_info_new (func, data);

133
      menuitem = gtk_menu_item_new_with_mnemonic (_(bidi_menu_entries[i].label));
134
      g_object_set_data (G_OBJECT (menuitem), I_("gtk-unicode-menu-entry"),
135
                         (gpointer)&bidi_menu_entries[i]);
136

Manish Singh's avatar
Manish Singh committed
137
      g_signal_connect_data (menuitem, "activate",
138
                             G_CALLBACK (activate_cb),
139 140
                             info, (GClosureNotify) callback_info_free, 0);

141 142 143 144 145
      gtk_widget_show (menuitem);
      gtk_menu_shell_append (menushell, menuitem);
    }
}

146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173
static void
append_n_lines (GString *str, const gchar *text, GSList *lines, gint n_lines)
{
  PangoLayoutLine *line;
  gint i;

  for (i = 0; i < n_lines; i++)
    {
      line = lines->data;
      g_string_append_len (str, &text[line->start_index], line->length);
      lines = lines->next;
    }
}

static void
limit_layout_lines (PangoLayout *layout)
{
  const gchar *text;
  GString     *str;
  GSList      *lines, *elem;
  gint         n_lines;

  n_lines = pango_layout_get_line_count (layout);
  
  if (n_lines >= DRAG_ICON_MAX_LINES)
    {
      text  = pango_layout_get_text (layout);
      str   = g_string_new (NULL);
174
      lines = pango_layout_get_lines_readonly (layout);
175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192

      /* get first lines */
      elem = lines;
      append_n_lines (str, text, elem,
                      DRAG_ICON_MAX_LINES / 2);

      g_string_append (str, "\n" ELLIPSIS_CHARACTER "\n");

      /* get last lines */
      elem = g_slist_nth (lines, n_lines - DRAG_ICON_MAX_LINES / 2);
      append_n_lines (str, text, elem,
                      DRAG_ICON_MAX_LINES / 2);

      pango_layout_set_text (layout, str->str, -1);
      g_string_free (str, TRUE);
    }
}

193 194
/**
 * _gtk_text_util_create_drag_icon:
195 196 197 198 199
 * @widget: #GtkWidget to extract the pango context
 * @text: a #gchar to render the icon
 * @len: length of @text, or -1 for NUL-terminated text
 *
 * Creates a drag and drop icon from @text.
200
 *
201
 * Returns: a #cairo_surface_t to use as DND icon
202
 */
203
cairo_surface_t *
204
_gtk_text_util_create_drag_icon (GtkWidget *widget,
205 206 207
                                 gchar     *text,
                                 gsize      len)
{
208
  GtkStyleContext *style_context;
209
  cairo_surface_t *surface;
210 211
  PangoContext *context;
  PangoLayout  *layout;
212
  cairo_t      *cr;
213 214
  gint          pixmap_height, pixmap_width;
  gint          layout_width, layout_height;
215
  GdkRGBA       color;
216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234

  g_return_val_if_fail (widget != NULL, NULL);
  g_return_val_if_fail (text != NULL, NULL);

  context = gtk_widget_get_pango_context (widget);
  layout  = pango_layout_new (context);

  pango_layout_set_text (layout, text, len);
  pango_layout_set_wrap (layout, PANGO_WRAP_WORD_CHAR);
  pango_layout_get_size (layout, &layout_width, &layout_height);

  layout_width = MIN (layout_width, DRAG_ICON_MAX_WIDTH * PANGO_SCALE);
  pango_layout_set_width (layout, layout_width);

  limit_layout_lines (layout);

  /* get again layout extents, they may have changed */
  pango_layout_get_size (layout, &layout_width, &layout_height);

235 236
  pixmap_width  = layout_width  / PANGO_SCALE;
  pixmap_height = layout_height / PANGO_SCALE;
237

238
  surface = gdk_window_create_similar_surface (gtk_widget_get_window (widget),
239 240
                                               CAIRO_CONTENT_COLOR_ALPHA,
                                               pixmap_width, pixmap_height);
241
  cr = cairo_create (surface);
242

243 244 245 246
  style_context = gtk_widget_get_style_context (widget);
  gtk_style_context_get_color (style_context,
                               gtk_style_context_get_state (style_context),
                               &color);
247
  gdk_cairo_set_source_rgba (cr, &color);
248
  pango_cairo_show_layout (cr, layout);
249

250
  cairo_destroy (cr);
251 252
  g_object_unref (layout);

253
  return surface;
254
}
255 256 257

static void
gtk_text_view_set_attributes_from_style (GtkTextView        *text_view,
258
                                         GtkTextAttributes  *values)
259
{
260 261 262 263 264
  GtkStyleContext *context;
  GdkRGBA bg_color, fg_color;
  GtkStateFlags state;

  context = gtk_widget_get_style_context (GTK_WIDGET (text_view));
265
  state = gtk_style_context_get_state (context);
266

267
G_GNUC_BEGIN_IGNORE_DEPRECATIONS
268
  gtk_style_context_get_background_color (context, state, &bg_color);
269
G_GNUC_END_IGNORE_DEPRECATIONS
270 271 272 273 274 275 276 277 278
  gtk_style_context_get_color (context, state, &fg_color);

  values->appearance.bg_color.red = CLAMP (bg_color.red * 65535. + 0.5, 0, 65535);
  values->appearance.bg_color.green = CLAMP (bg_color.green * 65535. + 0.5, 0, 65535);
  values->appearance.bg_color.blue = CLAMP (bg_color.blue * 65535. + 0.5, 0, 65535);

  values->appearance.fg_color.red = CLAMP (fg_color.red * 65535. + 0.5, 0, 65535);
  values->appearance.fg_color.green = CLAMP (fg_color.green * 65535. + 0.5, 0, 65535);
  values->appearance.fg_color.blue = CLAMP (fg_color.blue * 65535. + 0.5, 0, 65535);
279 280 281 282

  if (values->font)
    pango_font_description_free (values->font);

283
  gtk_style_context_get (context, state, "font", &values->font, NULL);
284 285
}

286
cairo_surface_t *
287 288 289 290 291
_gtk_text_util_create_rich_drag_icon (GtkWidget     *widget,
                                      GtkTextBuffer *buffer,
                                      GtkTextIter   *start,
                                      GtkTextIter   *end)
{
292
  GtkAllocation      allocation;
293
  cairo_surface_t   *surface;
294 295 296 297 298 299
  gint               layout_width, layout_height;
  GtkTextBuffer     *new_buffer;
  GtkTextLayout     *layout;
  GtkTextAttributes *style;
  PangoContext      *ltr_context, *rtl_context;
  GtkTextIter        iter;
300
  cairo_t           *cr;
301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327

   g_return_val_if_fail (GTK_IS_WIDGET (widget), NULL);
   g_return_val_if_fail (GTK_IS_TEXT_BUFFER (buffer), NULL);
   g_return_val_if_fail (start != NULL, NULL);
   g_return_val_if_fail (end != NULL, NULL);

   new_buffer = gtk_text_buffer_new (gtk_text_buffer_get_tag_table (buffer));
   gtk_text_buffer_get_start_iter (new_buffer, &iter);

   gtk_text_buffer_insert_range (new_buffer, &iter, start, end);

   gtk_text_buffer_get_start_iter (new_buffer, &iter);

   layout = gtk_text_layout_new ();

   ltr_context = gtk_widget_create_pango_context (widget);
   pango_context_set_base_dir (ltr_context, PANGO_DIRECTION_LTR);
   rtl_context = gtk_widget_create_pango_context (widget);
   pango_context_set_base_dir (rtl_context, PANGO_DIRECTION_RTL);

   gtk_text_layout_set_contexts (layout, ltr_context, rtl_context);

   g_object_unref (ltr_context);
   g_object_unref (rtl_context);

   style = gtk_text_attributes_new ();

328 329
   gtk_widget_get_allocation (widget, &allocation);
   layout_width = allocation.width;
330 331 332

   if (GTK_IS_TEXT_VIEW (widget))
     {
333
       gtk_text_view_set_attributes_from_style (GTK_TEXT_VIEW (widget), style);
334 335 336 337 338 339 340

       layout_width = layout_width
         - gtk_text_view_get_border_window_size (GTK_TEXT_VIEW (widget), GTK_TEXT_WINDOW_LEFT)
         - gtk_text_view_get_border_window_size (GTK_TEXT_VIEW (widget), GTK_TEXT_WINDOW_RIGHT);
     }

   style->direction = gtk_widget_get_direction (widget);
Yosef Or Boczko's avatar
Yosef Or Boczko committed
341
   style->wrap_mode = GTK_WRAP_WORD_CHAR;
342 343 344 345 346 347 348 349 350 351 352 353 354 355

   gtk_text_layout_set_default_style (layout, style);
   gtk_text_attributes_unref (style);

   gtk_text_layout_set_buffer (layout, new_buffer);
   gtk_text_layout_set_cursor_visible (layout, FALSE);
   gtk_text_layout_set_screen_width (layout, layout_width);

   gtk_text_layout_validate (layout, DRAG_ICON_MAX_HEIGHT);
   gtk_text_layout_get_size (layout, &layout_width, &layout_height);

   layout_width = MIN (layout_width, DRAG_ICON_MAX_WIDTH);
   layout_height = MIN (layout_height, DRAG_ICON_MAX_HEIGHT);

356
   surface = gdk_window_create_similar_surface (gtk_widget_get_window (widget),
357 358
                                                CAIRO_CONTENT_COLOR_ALPHA,
                                                layout_width, layout_height);
359

360
   cr = cairo_create (surface);
361

362
   gtk_text_layout_draw (layout, widget, cr, NULL);
363

364
   cairo_destroy (cr);
365 366 367
   g_object_unref (layout);
   g_object_unref (new_buffer);

368
   return surface;
369
}
370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390


static gint
layout_get_char_width (PangoLayout *layout)
{
  gint width;
  PangoFontMetrics *metrics;
  const PangoFontDescription *font_desc;
  PangoContext *context = pango_layout_get_context (layout);

  font_desc = pango_layout_get_font_description (layout);
  if (!font_desc)
    font_desc = pango_context_get_font_description (context);

  metrics = pango_context_get_metrics (context, font_desc, NULL);
  width = pango_font_metrics_get_approximate_char_width (metrics);
  pango_font_metrics_unref (metrics);

  return width;
}

391
/*
392 393 394
 * _gtk_text_util_get_block_cursor_location
 * @layout: a #PangoLayout
 * @index: index at which cursor is located
395
 * @pos: cursor location
396
 * @at_line_end: whether cursor is drawn at line end, not over some
397
 * character
398 399
 *
 * Returns: whether cursor should actually be drawn as a rectangle.
400 401
 *     It may not be the case if character at index is invisible.
 */
402 403 404 405 406 407 408 409 410 411
gboolean
_gtk_text_util_get_block_cursor_location (PangoLayout    *layout,
					  gint            index,
					  PangoRectangle *pos,
					  gboolean       *at_line_end)
{
  PangoRectangle strong_pos, weak_pos;
  PangoLayoutLine *layout_line;
  gboolean rtl;
  gint line_no;
412
  const gchar *text;
413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436

  g_return_val_if_fail (layout != NULL, FALSE);
  g_return_val_if_fail (index >= 0, FALSE);
  g_return_val_if_fail (pos != NULL, FALSE);

  pango_layout_index_to_pos (layout, index, pos);

  if (pos->width != 0)
    {
      /* cursor is at some visible character, good */
      if (at_line_end)
	*at_line_end = FALSE;
      if (pos->width < 0)
	{
	  pos->x += pos->width;
	  pos->width = -pos->width;
	}
      return TRUE;
    }

  pango_layout_index_to_line_x (layout, index, FALSE, &line_no, NULL);
  layout_line = pango_layout_get_line_readonly (layout, line_no);
  g_return_val_if_fail (layout_line != NULL, FALSE);

437 438
  text = pango_layout_get_text (layout);

439 440
  if (index < layout_line->start_index + layout_line->length)
    {
441 442 443 444 445 446 447 448 449 450
      /* this may be a zero-width character in the middle of the line,
       * or it could be a character where line is wrapped, we do want
       * block cursor in latter case */
      if (g_utf8_next_char (text + index) - text !=
	  layout_line->start_index + layout_line->length)
	{
	  /* zero-width character in the middle of the line, do not
	   * bother with block cursor */
	  return FALSE;
	}
451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469
    }

  /* Cursor is at the line end. It may be an empty line, or it could
   * be on the left or on the right depending on text direction, or it
   * even could be in the middle of visual layout in bidi text. */

  pango_layout_get_cursor_pos (layout, index, &strong_pos, &weak_pos);

  if (strong_pos.x != weak_pos.x)
    {
      /* do not show block cursor in this case, since the character typed
       * in may or may not appear at the cursor position */
      return FALSE;
    }

  /* In case when index points to the end of line, pos->x is always most right
   * pixel of the layout line, so we need to correct it for RTL text. */
  if (layout_line->length)
    {
470
      if (layout_line->resolved_dir == PANGO_DIRECTION_RTL)
471 472 473 474
	{
	  PangoLayoutIter *iter;
	  PangoRectangle line_rect;
	  gint i;
475 476 477 478 479 480 481 482
	  gint left, right;
	  const gchar *p;

	  p = g_utf8_prev_char (text + index);

	  pango_layout_line_index_to_x (layout_line, p - text, FALSE, &left);
	  pango_layout_line_index_to_x (layout_line, p - text, TRUE, &right);
	  pos->x = MIN (left, right);
483 484 485 486 487 488 489 490

	  iter = pango_layout_get_iter (layout);
	  for (i = 0; i < line_no; i++)
	    pango_layout_iter_next_line (iter);
	  pango_layout_iter_get_line_extents (iter, NULL, &line_rect);
	  pango_layout_iter_free (iter);

          rtl = TRUE;
491
	  pos->x += line_rect.x;
492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511
	}
      else
	rtl = FALSE;
    }
  else
    {
      PangoContext *context = pango_layout_get_context (layout);
      rtl = pango_context_get_base_dir (context) == PANGO_DIRECTION_RTL;
    }

  pos->width = layout_get_char_width (layout);

  if (rtl)
    pos->x -= pos->width - 1;

  if (at_line_end)
    *at_line_end = TRUE;

  return pos->width != 0;
}