libs/gtkmm2ext/cairocell.cc

   1 /*
   2   Copyright (C) 2011 Paul Davis
   3
   4   This program is free software; you can redistribute it and/or modify
   5   it under the terms of the GNU General Public License as published by
   6   the Free Software Foundation; either version 2 of the License, or
   7   (at your option) any later version.
   8
   9   This program is distributed in the hope that it will be useful,
  10   but WITHOUT ANY WARRANTY; without even the implied warranty of
  11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12   GNU General Public License for more details.
  13
  14   You should have received a copy of the GNU General Public License
  15   along with this program; if not, write to the Free Software
  16   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17
  18 */
  19
  20 #include <algorithm>
  21 #include <cmath>
  22 #include <iostream>
  23
  24 #include "gtkmm2ext/cairocell.h"
  25 #include "gtkmm2ext/utils.h"
  26
  27 using std::string;
  28 using std::map;
  29 using std::max;
  30 using std::cerr;
  31 using std::endl;
  32 using namespace Gtkmm2ext;
  33
  34 static const double cairo_font_fudge = 1.5;
  35
  36 CairoFontDescription::CairoFontDescription (Pango::FontDescription& fd)
  37 {
  38         _size = cairo_font_fudge * (fd.get_size() / PANGO_SCALE);
  39
  40         switch (fd.get_style()) {
  41         case Pango::STYLE_NORMAL:
  42                 _slant = Cairo::FONT_SLANT_NORMAL;
  43                 break;
  44         case Pango::STYLE_OBLIQUE:
  45                 _slant = Cairo::FONT_SLANT_OBLIQUE;
  46                 break;
  47         case Pango::STYLE_ITALIC:
  48                 _slant = Cairo::FONT_SLANT_ITALIC;
  49                 break;
  50         }
  51
  52         switch (fd.get_weight()) {
  53         case Pango::WEIGHT_ULTRALIGHT:
  54                 _weight = Cairo::FONT_WEIGHT_NORMAL;
  55                 break;
  56
  57         case Pango::WEIGHT_LIGHT:
  58                 _weight = Cairo::FONT_WEIGHT_NORMAL;
  59                 break;
  60
  61         case Pango::WEIGHT_NORMAL:
  62                 _weight = Cairo::FONT_WEIGHT_NORMAL;
  63                 break;
  64
  65         case Pango::WEIGHT_SEMIBOLD:
  66                 _weight = Cairo::FONT_WEIGHT_BOLD;
  67                 break;
  68
  69         case Pango::WEIGHT_BOLD:
  70                 _weight = Cairo::FONT_WEIGHT_BOLD;
  71                 break;
  72
  73         case Pango::WEIGHT_ULTRABOLD:
  74                 _weight = Cairo::FONT_WEIGHT_BOLD;
  75                 break;
  76
  77         case Pango::WEIGHT_HEAVY:
  78                 _weight = Cairo::FONT_WEIGHT_BOLD;
  79                 break;
  80
  81         }
  82
  83         face = fd.get_family();
  84 }
  85
  86 CairoCell::CairoCell (int32_t id)
  87         : _id (id)
  88         , _visible (true)
  89         , _xpad (0)
  90 {
  91         bbox.x = 0;
  92         bbox.y = 0;
  93         bbox.width = 0;
  94         bbox.height = 0;
  95 }
  96
  97 CairoTextCell::CairoTextCell (int32_t id, double wc, boost::shared_ptr<CairoFontDescription> font)
  98         : CairoCell (id)
  99         , _width_chars (wc)
 100         , _font (font)
 101         , y_offset (0)
 102         , x_offset (0)
 103 {
 104 }
 105
 106 void
 107 CairoTextCell::set_text (const std::string& txt)
 108 {
 109         _text = txt;
 110 }
 111
 112 void
 113 CairoTextCell::render (Cairo::RefPtr<Cairo::Context>& context)
 114 {
 115         if (!_visible || _width_chars == 0) {
 116                 return;
 117         }
 118
 119         context->save ();
 120
 121         context->rectangle (bbox.x, bbox.y, bbox.width, bbox.height);
 122         context->clip ();
 123
 124         _font->apply (context);
 125         context->move_to (bbox.x, bbox.y + bbox.height + y_offset);
 126         context->show_text (_text);
 127
 128         context->restore ();
 129 }
 130
 131 void
 132 CairoTextCell::set_size (Cairo::RefPtr<Cairo::Context>& context)
 133 {
 134         const uint32_t lim = (uint32_t) ceil (_width_chars);
 135         char buf[lim+1];
 136         uint32_t n;
 137         double max_width = 0.0;
 138         double max_height = 0.0;
 139         Cairo::TextExtents ext;
 140         double bsum = 0;
 141
 142         buf[lim] = '\0';
 143
 144         _font->apply (context);
 145
 146         for (int digit = 0; digit < 10; digit++) {
 147
 148                 for (n = 0; n < lim; ++n) {
 149                         buf[n] = '0' + digit;
 150                 }
 151
 152                 context->get_text_extents (buf, ext);
 153
 154                 max_width = max (ext.width + ext.x_bearing, max_width);
 155                 max_height = max (ext.height, max_height);
 156                 bsum += ext.x_bearing;
 157         }
 158
 159         /* add the average x-bearing for all digits as right hand side padding */
 160
 161         bbox.width = max_width + (bsum/10.0);
 162
 163         /* some fonts and some digits get their extents computed "too small", so fudge this
 164            by adding 2
 165         */
 166         bbox.height = max_height;
 167 }
 168
 169 CairoCharCell::CairoCharCell (int32_t id, char c)
 170         : CairoTextCell (id, 1)
 171 {
 172         _text = c;
 173 }
 174
 175 void
 176 CairoCharCell::set_size (Cairo::RefPtr<Cairo::Context>& context)
 177 {
 178         Cairo::TextExtents ext;
 179
 180         _font->apply (context);
 181
 182         {
 183                 const char* buf = "8";
 184                 context->get_text_extents (buf, ext);
 185                 /* same height as an "8" */
 186                 bbox.height = ext.height;
 187         }
 188
 189         {
 190                 const char* buf = ":";
 191                 context->get_text_extents (buf, ext);
 192                 bbox.width = ext.width + (2.0 * ext.x_bearing);
 193                 /* center vertically */
 194                 y_offset = (ext.height - bbox.height) / 2.0;
 195         }
 196 }
 197
 198 CairoEditableText::CairoEditableText (boost::shared_ptr<CairoFontDescription> font)
 199         : editing_cell (0)
 200         , _draw_bg (true)
 201         , max_cell_width (0)
 202         , max_cell_height (0)
 203         , _corner_radius (9)
 204         , _xpad (0)
 205         , _ypad (0)
 206 {
 207         set_font (font);
 208
 209         add_events (Gdk::POINTER_MOTION_HINT_MASK | Gdk::SCROLL_MASK | Gdk::KEY_PRESS_MASK | Gdk::KEY_RELEASE_MASK |
 210                     Gdk::BUTTON_PRESS_MASK | Gdk::BUTTON_RELEASE_MASK | Gdk::SCROLL_MASK);
 211         set_flags (Gtk::CAN_FOCUS);
 212
 213         set_can_default (true);
 214         set_receives_default (true);
 215 }
 216
 217 CairoEditableText::~CairoEditableText ()
 218 {
 219         /* we don't own cells */
 220 }
 221
 222 bool
 223 CairoEditableText::on_scroll_event (GdkEventScroll* ev)
 224 {
 225         CairoCell* cell = find_cell (ev->x, ev->y);
 226
 227         if (cell) {
 228                 return scroll (ev, cell);
 229         }
 230
 231         return false;
 232 }
 233
 234 bool
 235 CairoEditableText::on_focus_in_event (GdkEventFocus* ev)
 236 {
 237         return false;
 238 }
 239
 240 bool
 241 CairoEditableText::on_focus_out_event (GdkEventFocus* ev)
 242 {
 243         if (editing_cell) {
 244                 queue_draw_cell (editing_cell);
 245                 editing_cell = 0;
 246         }
 247         return false;
 248 }
 249
 250 void
 251 CairoEditableText::add_cell (CairoCell* cell)
 252 {
 253         cells.push_back (cell);
 254
 255         CairoTextCell* tc = dynamic_cast<CairoTextCell*>(cell);
 256
 257         if (tc) {
 258                 tc->set_font (_font);
 259         }
 260
 261         queue_resize ();
 262 }
 263
 264 void
 265 CairoEditableText::clear_cells ()
 266 {
 267         cells.clear ();
 268         queue_resize ();
 269 }
 270
 271 void
 272 CairoEditableText::set_width_chars (CairoTextCell* cell, uint32_t wc)
 273 {
 274         if (cell) {
 275                 cell->set_width_chars (wc);
 276                 queue_resize ();
 277         }
 278 }
 279
 280 void
 281 CairoEditableText::set_text (CairoTextCell* cell, const string& text)
 282 {
 283         cell->set_text (text);
 284         queue_draw_cell (cell);
 285 }
 286
 287 bool
 288 CairoEditableText::on_expose_event (GdkEventExpose* ev)
 289 {
 290         Glib::RefPtr<Gdk::Window> win = get_window ();
 291
 292         if (!win) {
 293                 std::cerr << "CET: no window to draw on\n";
 294                 return false;
 295         }
 296
 297         Cairo::RefPtr<Cairo::Context> context = win->create_cairo_context();
 298
 299         if (cells.empty()) {
 300                 return true;
 301         }
 302
 303         context->rectangle (ev->area.x, ev->area.y, ev->area.width, ev->area.height);
 304         context->clip ();
 305
 306         Gtk::Allocation alloc = get_allocation ();
 307         double width = alloc.get_width();
 308         double height = alloc.get_height ();
 309
 310         if (_draw_bg) {
 311                 context->set_source_rgba (bg_r, bg_g, bg_b, bg_a);
 312                 if (_corner_radius) {
 313                         rounded_rectangle (context, 0, 0, width, height, _corner_radius);
 314                 } else {
 315                         context->rectangle (0, 0, width, height);
 316                 }
 317                 context->fill ();
 318         }
 319
 320         for (CellMap::iterator i = cells.begin(); i != cells.end(); ++i) {
 321
 322                 CairoCell* cell = (*i);
 323
 324                 /* is cell inside the expose area?
 325                  */
 326
 327                 if (cell->intersects (ev->area)) {
 328                         if (cell == editing_cell) {
 329                                 context->set_source_rgba (edit_r, edit_b, edit_g, edit_a);
 330                         } else {
 331                                 context->set_source_rgba (r, g, b, a);
 332                         }
 333
 334                         cell->render (context);
 335                 }
 336         }
 337
 338         return true;
 339 }
 340
 341 void
 342 CairoEditableText::queue_draw_cell (CairoCell* cell)
 343 {
 344         Glib::RefPtr<Gdk::Window> win = get_window();
 345
 346         if (!win) {
 347                 return;
 348         }
 349
 350         Gdk::Rectangle r;
 351
 352         r.set_x (cell->x());
 353         r.set_y (cell->y());
 354         r.set_width (cell->width());
 355         r.set_height (cell->height());
 356
 357         Gdk::Region rg (r);
 358         win->invalidate_region (rg, true);
 359 }
 360
 361 CairoCell*
 362 CairoEditableText::find_cell (uint32_t x, uint32_t y)
 363 {
 364         for (CellMap::iterator i = cells.begin(); i != cells.end(); ++i) {
 365                 if ((*i)->covers (x, y)) {
 366                         return (*i);
 367                 }
 368         }
 369
 370         return 0;
 371 }
 372
 373 bool
 374 CairoEditableText::on_button_press_event (GdkEventButton* ev)
 375 {
 376         CairoCell* cell = find_cell (ev->x, ev->y);
 377         return button_press (ev, cell);
 378 }
 379
 380 bool
 381 CairoEditableText::on_button_release_event (GdkEventButton* ev)
 382 {
 383         CairoCell* cell = find_cell (ev->x, ev->y);
 384         return button_release (ev, cell);
 385 }
 386
 387 void
 388 CairoEditableText::start_editing (CairoCell* cell)
 389 {
 390         stop_editing ();
 391
 392         if (cell) {
 393                 editing_cell = cell;
 394                 queue_draw_cell (cell);
 395                 grab_focus ();
 396         }
 397 }
 398
 399 void
 400 CairoEditableText::stop_editing ()
 401 {
 402         if (editing_cell) {
 403                 queue_draw_cell (editing_cell);
 404                 editing_cell = 0;
 405         }
 406 }
 407
 408 void
 409 CairoEditableText::set_cell_sizes ()
 410 {
 411         Glib::RefPtr<Gdk::Window> win = get_window();
 412
 413         if (!win) {
 414                 return;
 415         }
 416
 417         Cairo::RefPtr<Cairo::Context> context = win->create_cairo_context();
 418
 419         if (!context) {
 420                 return;
 421         }
 422
 423         for (CellMap::iterator i = cells.begin(); i != cells.end(); ++i) {
 424                 (*i)->set_size (context);
 425         }
 426 }
 427
 428 void
 429 CairoEditableText::on_size_request (GtkRequisition* req)
 430 {
 431         set_cell_sizes ();
 432
 433         max_cell_width = 0;
 434         max_cell_height = 0;
 435
 436         for (CellMap::iterator i = cells.begin(); i != cells.end(); ++i) {
 437                 max_cell_width += (*i)->width();
 438                 max_cell_height = std::max ((double) (*i)->height(), max_cell_height);
 439         }
 440
 441         req->width = max_cell_width;
 442         req->height = max_cell_height;
 443 }
 444
 445 void
 446 CairoEditableText::on_size_allocate (Gtk::Allocation& alloc)
 447 {
 448         Misc::on_size_allocate (alloc);
 449
 450         /* position each cell so that its centered in the allocated space
 451          */
 452
 453         double x = (alloc.get_width() - max_cell_width)/2.0;
 454         double y = (alloc.get_height() - max_cell_height)/2.0;
 455
 456         CellMap::iterator i = cells.begin();
 457
 458         while (i != cells.end()) {
 459                 CairoCell* cell = (*i);
 460
 461                 cell->set_position (x, y);
 462                 x += cell->width ();
 463
 464                 if (++i != cells.end()) {
 465                         /* only add cell padding intra-cellularly */
 466                         x += cell->xpad();
 467                 } else {
 468                         break;
 469                 }
 470         }
 471 }
 472
 473 void
 474 CairoEditableText::set_font (Pango::FontDescription& fd)
 475 {
 476         boost::shared_ptr<CairoFontDescription> cd (new CairoFontDescription (fd));
 477         set_font (cd);
 478 }
 479
 480 void
 481 CairoEditableText::set_font (boost::shared_ptr<CairoFontDescription> fd)
 482 {
 483         for (CellMap::iterator i = cells.begin(); i != cells.end(); ++i) {
 484                 CairoTextCell* tc = dynamic_cast<CairoTextCell*>(*i);
 485                 if (tc && (!tc->font() || tc->font() == _font)) {
 486                         tc->set_font (fd);
 487                 }
 488         }
 489
 490         _font = fd;
 491
 492         queue_resize ();
 493         queue_draw ();
 494 }
 495