clients/dnd.c

   1 /*
   2  * Copyright © 2010 Kristian Høgsberg
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and its
   5  * documentation for any purpose is hereby granted without fee, provided that
   6  * the above copyright notice appear in all copies and that both that copyright
   7  * notice and this permission notice appear in supporting documentation, and
   8  * that the name of the copyright holders not be used in advertising or
   9  * publicity pertaining to distribution of the software without specific,
  10  * written prior permission.  The copyright holders make no representations
  11  * about the suitability of this software for any purpose.  It is provided "as
  12  * is" without express or implied warranty.
  13  *
  14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
  15  * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
  16  * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
  17  * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
  18  * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  19  * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
  20  * OF THIS SOFTWARE.
  21  */
  22
  23 #include <stdint.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <fcntl.h>
  28 #include <unistd.h>
  29 #include <math.h>
  30 #include <sys/time.h>
  31 #include <cairo.h>
  32 #include <sys/epoll.h>
  33
  34 #include <wayland-client.h>
  35
  36 #include "window.h"
  37 #include "cairo-util.h"
  38
  39 struct dnd {
  40         struct window *window;
  41         struct display *display;
  42         uint32_t key;
  43         struct item *items[16];
  44 };
  45
  46 struct dnd_drag {
  47         cairo_surface_t *translucent;
  48         cairo_surface_t *opaque;
  49         int hotspot_x, hotspot_y;
  50         struct dnd *dnd;
  51         struct input *input;
  52         uint32_t time;
  53         struct item *item;
  54         int x_offset, y_offset;
  55         const char *mime_type;
  56
  57         struct wl_data_source *data_source;
  58 };
  59
  60 struct item {
  61         cairo_surface_t *surface;
  62         int seed;
  63         int x, y;
  64 };
  65
  66 struct dnd_flower_message {
  67         int seed, x_offset, y_offset;
  68 };
  69
  70
  71 static const int item_width = 64;
  72 static const int item_height = 64;
  73 static const int item_padding = 16;
  74
  75 static struct item *
  76 item_create(struct display *display, int x, int y, int seed)
  77 {
  78         struct item *item;
  79         struct timeval tv;
  80
  81         item = malloc(sizeof *item);
  82         if (item == NULL)
  83                 return NULL;
  84
  85
  86         gettimeofday(&tv, NULL);
  87         item->seed = seed ? seed : tv.tv_usec;
  88         srandom(item->seed);
  89
  90         const int petal_count = 3 + random() % 5;
  91         const double r1 = 20 + random() % 10;
  92         const double r2 = 5 + random() % 12;
  93         const double u = (10 + random() % 90) / 100.0;
  94         const double v = (random() % 90) / 100.0;
  95
  96         cairo_t *cr;
  97         int i;
  98         double t, dt = 2 * M_PI / (petal_count * 2);
  99         double x1, y1, x2, y2, x3, y3;
 100         struct rectangle rect;
 101
 102
 103         rect.width = item_width;
 104         rect.height = item_height;
 105         item->surface = display_create_surface(display, NULL, &rect, 0);
 106
 107         item->x = x;
 108         item->y = y;
 109
 110         cr = cairo_create(item->surface);
 111         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 112         cairo_set_source_rgba(cr, 0, 0, 0, 0);
 113         cairo_paint(cr);
 114
 115         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 116         cairo_translate(cr, item_width / 2, item_height / 2);
 117         t = random();
 118         cairo_move_to(cr, cos(t) * r1, sin(t) * r1);
 119         for (i = 0; i < petal_count; i++, t += dt * 2) {
 120                 x1 = cos(t) * r1;
 121                 y1 = sin(t) * r1;
 122                 x2 = cos(t + dt) * r2;
 123                 y2 = sin(t + dt) * r2;
 124                 x3 = cos(t + 2 * dt) * r1;
 125                 y3 = sin(t + 2 * dt) * r1;
 126
 127                 cairo_curve_to(cr,
 128                                x1 - y1 * u, y1 + x1 * u,
 129                                x2 + y2 * v, y2 - x2 * v,
 130                                x2, y2);
 131
 132                 cairo_curve_to(cr,
 133                                x2 - y2 * v, y2 + x2 * v,
 134                                x3 + y3 * u, y3 - x3 * u,
 135                                x3, y3);
 136         }
 137
 138         cairo_close_path(cr);
 139
 140         cairo_set_source_rgba(cr,
 141                               0.5 + (random() % 50) / 49.0,
 142                               0.5 + (random() % 50) / 49.0,
 143                               0.5 + (random() % 50) / 49.0,
 144                               0.5 + (random() % 100) / 99.0);
 145
 146         cairo_fill_preserve(cr);
 147
 148         cairo_set_line_width(cr, 1);
 149         cairo_set_source_rgba(cr,
 150                               0.5 + (random() % 50) / 49.0,
 151                               0.5 + (random() % 50) / 49.0,
 152                               0.5 + (random() % 50) / 49.0,
 153                               0.5 + (random() % 100) / 99.0);
 154         cairo_stroke(cr);
 155
 156         cairo_destroy(cr);
 157
 158         return item;
 159 }
 160
 161 static void
 162 dnd_draw(struct dnd *dnd)
 163 {
 164         struct rectangle allocation;
 165         cairo_t *cr;
 166         cairo_surface_t *surface;
 167         int i;
 168
 169         window_draw(dnd->window);
 170
 171         surface = window_get_surface(dnd->window);
 172         cr = cairo_create(surface);
 173         window_get_child_allocation(dnd->window, &allocation);
 174         cairo_rectangle(cr, allocation.x, allocation.y,
 175                         allocation.width, allocation.height);
 176
 177         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 178         cairo_set_source_rgba(cr, 0, 0, 0, 0.8);
 179         cairo_fill(cr);
 180
 181         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 182         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 183                 if (!dnd->items[i])
 184                         continue;
 185                 cairo_set_source_surface(cr, dnd->items[i]->surface,
 186                                          dnd->items[i]->x + allocation.x,
 187                                          dnd->items[i]->y + allocation.y);
 188                 cairo_paint(cr);
 189         }
 190
 191         cairo_destroy(cr);
 192         cairo_surface_destroy(surface);
 193         window_flush(dnd->window);
 194 }
 195
 196 static void
 197 redraw_handler(struct window *window, void *data)
 198 {
 199         struct dnd *dnd = data;
 200
 201         dnd_draw(dnd);
 202 }
 203
 204 static void
 205 keyboard_focus_handler(struct window *window,
 206                        struct input *device, void *data)
 207 {
 208         struct dnd *dnd = data;
 209
 210         window_schedule_redraw(dnd->window);
 211 }
 212
 213 static int
 214 dnd_add_item(struct dnd *dnd, struct item *item)
 215 {
 216         int i;
 217
 218         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 219                 if (dnd->items[i] == 0) {
 220                         dnd->items[i] = item;
 221                         return i;
 222                 }
 223         }
 224         return -1;
 225 }
 226
 227 static struct item *
 228 dnd_get_item(struct dnd *dnd, int32_t x, int32_t y)
 229 {
 230         struct item *item;
 231         struct rectangle allocation;
 232         int i;
 233
 234         window_get_child_allocation(dnd->window, &allocation);
 235
 236         x -= allocation.x;
 237         y -= allocation.y;
 238
 239         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 240                 item = dnd->items[i];
 241                 if (item &&
 242                     item->x <= x && x < item->x + item_width &&
 243                     item->y <= y && y < item->y + item_height)
 244                         return item;
 245         }
 246
 247         return NULL;
 248 }
 249
 250 static void
 251 data_source_target(void *data,
 252                    struct wl_data_source *source, const char *mime_type)
 253 {
 254         struct dnd_drag *dnd_drag = data;
 255         struct dnd *dnd = dnd_drag->dnd;
 256         cairo_surface_t *surface;
 257         struct wl_buffer *buffer;
 258         struct wl_data_device *device;
 259
 260         device = input_get_data_device(dnd_drag->input);
 261         dnd_drag->mime_type = mime_type;
 262         if (mime_type)
 263                 surface = dnd_drag->opaque;
 264         else
 265                 surface = dnd_drag->translucent;
 266
 267         buffer = display_get_buffer_for_surface(dnd->display, surface);
 268         wl_data_device_attach(device, dnd_drag->time, buffer,
 269                                   dnd_drag->hotspot_x, dnd_drag->hotspot_y);
 270 }
 271
 272 static void
 273 data_source_send(void *data, struct wl_data_source *source,
 274                  const char *mime_type, int32_t fd)
 275 {
 276         struct dnd_flower_message dnd_flower_message;
 277         struct dnd_drag *dnd_drag = data;
 278
 279         dnd_flower_message.seed = dnd_drag->item->seed;
 280         dnd_flower_message.x_offset = dnd_drag->x_offset;
 281         dnd_flower_message.y_offset = dnd_drag->y_offset;
 282
 283         write(fd, &dnd_flower_message, sizeof dnd_flower_message);
 284         close(fd);
 285 }
 286
 287 static void
 288 data_source_cancelled(void *data, struct wl_data_source *source)
 289 {
 290         struct dnd_drag *dnd_drag = data;
 291
 292         /* The 'cancelled' event means that the source is no longer in
 293          * use by the drag (or current selection).  We need to clean
 294          * up the drag object created and the local state. */
 295
 296         wl_data_source_destroy(dnd_drag->data_source);
 297
 298         /* Destroy the item that has been dragged out */
 299         cairo_surface_destroy(dnd_drag->item->surface);
 300         free(dnd_drag->item);
 301
 302         cairo_surface_destroy(dnd_drag->translucent);
 303         cairo_surface_destroy(dnd_drag->opaque);
 304         free(dnd_drag);
 305 }
 306
 307 static const struct wl_data_source_listener data_source_listener = {
 308         data_source_target,
 309         data_source_send,
 310         data_source_cancelled
 311 };
 312
 313 static cairo_surface_t *
 314 create_drag_cursor(struct dnd_drag *dnd_drag,
 315                    struct item *item, int32_t x, int32_t y, double opacity)
 316 {
 317         struct dnd *dnd = dnd_drag->dnd;
 318         cairo_surface_t *surface, *pointer;
 319         int32_t pointer_width, pointer_height, hotspot_x, hotspot_y;
 320         struct rectangle rectangle;
 321         cairo_pattern_t *pattern;
 322         cairo_t *cr;
 323
 324         pointer = display_get_pointer_surface(dnd->display,
 325                                               POINTER_DRAGGING,
 326                                               &pointer_width,
 327                                               &pointer_height,
 328                                               &hotspot_x,
 329                                               &hotspot_y);
 330
 331         rectangle.width = item_width + 2 * pointer_width;
 332         rectangle.height = item_height + 2 * pointer_height;
 333         surface = display_create_surface(dnd->display, NULL, &rectangle, 0);
 334
 335         cr = cairo_create(surface);
 336         cairo_translate(cr, pointer_width, pointer_height);
 337
 338         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 339         cairo_set_source_rgba(cr, 0, 0, 0, 0);
 340         cairo_paint(cr);
 341
 342         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 343         cairo_set_source_surface(cr, item->surface, 0, 0);
 344         pattern = cairo_pattern_create_rgba(0, 0, 0, opacity);
 345         cairo_mask(cr, pattern);
 346         cairo_pattern_destroy(pattern);
 347
 348         cairo_set_source_surface(cr, pointer,
 349                                  x - item->x - hotspot_x,
 350                                  y - item->y - hotspot_y);
 351         cairo_surface_destroy(pointer);
 352         cairo_paint(cr);
 353         /* FIXME: more cairo-gl brokeness */
 354         surface_flush_device(surface);
 355         cairo_destroy(cr);
 356
 357         dnd_drag->hotspot_x = pointer_width + x - item->x;
 358         dnd_drag->hotspot_y = pointer_height + y - item->y;
 359
 360         return surface;
 361 }
 362
 363 static void
 364 dnd_button_handler(struct widget *widget,
 365                    struct input *input, uint32_t time,
 366                    int button, int state, void *data)
 367 {
 368         struct window *window = data;
 369         struct dnd *dnd = window_get_user_data(window);
 370         int32_t x, y;
 371         struct item *item;
 372         struct rectangle allocation;
 373         struct dnd_drag *dnd_drag;
 374         int i;
 375
 376         window_get_child_allocation(dnd->window, &allocation);
 377         input_get_position(input, &x, &y);
 378         item = dnd_get_item(dnd, x, y);
 379         x -= allocation.x;
 380         y -= allocation.y;
 381
 382         if (item && state == 1) {
 383                 dnd_drag = malloc(sizeof *dnd_drag);
 384                 dnd_drag->dnd = dnd;
 385                 dnd_drag->input = input;
 386                 dnd_drag->time = time;
 387                 dnd_drag->item = item;
 388                 dnd_drag->x_offset = x - item->x;
 389                 dnd_drag->y_offset = y - item->y;
 390
 391                 for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 392                         if (item == dnd->items[i]){
 393                                 dnd->items[i] = 0;
 394                                 break;
 395                         }
 396                 }
 397
 398                 dnd_drag->data_source =
 399                         display_create_data_source(dnd->display);
 400                 wl_data_source_add_listener(dnd_drag->data_source,
 401                                             &data_source_listener,
 402                                             dnd_drag);
 403                 wl_data_source_offer(dnd_drag->data_source,
 404                                      "application/x-wayland-dnd-flower");
 405                 wl_data_source_offer(dnd_drag->data_source,
 406                                      "text/plain; charset=utf-8");
 407                 wl_data_device_start_drag(input_get_data_device(input),
 408                                           dnd_drag->data_source,
 409                                           window_get_wl_surface(window),
 410                                           time);
 411
 412                 input_set_pointer_image(input, time, POINTER_DRAGGING);
 413
 414                 dnd_drag->opaque =
 415                         create_drag_cursor(dnd_drag, item, x, y, 1);
 416                 dnd_drag->translucent =
 417                         create_drag_cursor(dnd_drag, item, x, y, 0.2);
 418
 419                 window_schedule_redraw(dnd->window);
 420         }
 421 }
 422
 423 static int
 424 lookup_cursor(struct dnd *dnd, int x, int y)
 425 {
 426         struct item *item;
 427
 428         item = dnd_get_item(dnd, x, y);
 429         if (item)
 430                 return POINTER_HAND1;
 431         else
 432                 return POINTER_LEFT_PTR;
 433 }
 434
 435 static void
 436 dnd_enter_handler(struct widget *widget,
 437                   struct input *input, uint32_t time,
 438                   int32_t x, int32_t y, void *data)
 439 {
 440 }
 441
 442 static int
 443 dnd_motion_handler(struct widget *widget,
 444                    struct input *input, uint32_t time,
 445                    int32_t x, int32_t y, void *data)
 446 {
 447         struct window *window = data;
 448         struct dnd *dnd = window_get_user_data(window);
 449
 450         return lookup_cursor(dnd, x, y);
 451 }
 452
 453 static void
 454 dnd_data_handler(struct window *window,
 455                  struct input *input, uint32_t time,
 456                  int32_t x, int32_t y, const char **types, void *data)
 457 {
 458         struct dnd *dnd = data;
 459
 460         if (!dnd_get_item(dnd, x, y)) {
 461                 input_accept(input, time, types[0]);
 462         } else {
 463                 input_accept(input, time, NULL);
 464         }
 465 }
 466
 467 static void
 468 dnd_receive_func(void *data, size_t len, int32_t x, int32_t y, void *user_data)
 469 {
 470         struct dnd *dnd = user_data;
 471         struct dnd_flower_message *message = data;
 472         struct item *item;
 473         struct rectangle allocation;
 474
 475         if (len == 0) {
 476                 return;
 477         } else if (len != sizeof *message) {
 478                 fprintf(stderr, "odd message length %ld, expected %ld\n",
 479                         len, sizeof *message);
 480                 return;
 481         }
 482
 483         window_get_child_allocation(dnd->window, &allocation);
 484         item = item_create(dnd->display,
 485                            x - message->x_offset - allocation.x,
 486                            y - message->y_offset - allocation.y,
 487                            message->seed);
 488
 489         dnd_add_item(dnd, item);
 490         window_schedule_redraw(dnd->window);
 491 }
 492
 493 static void
 494 dnd_drop_handler(struct window *window, struct input *input,
 495                  int32_t x, int32_t y, void *data)
 496 {
 497         struct dnd *dnd = data;
 498
 499         if (dnd_get_item(dnd, x, y)) {
 500                 fprintf(stderr, "got 'drop', but no target\n");
 501                 return;
 502         }
 503
 504         input_receive_drag_data(input,
 505                                 "application/x-wayland-dnd-flower",
 506                                 dnd_receive_func, dnd);
 507 }
 508
 509 static struct dnd *
 510 dnd_create(struct display *display)
 511 {
 512         struct dnd *dnd;
 513         int i, x, y;
 514         int32_t width, height;
 515         struct widget *widget;
 516
 517         dnd = malloc(sizeof *dnd);
 518         if (dnd == NULL)
 519                 return dnd;
 520         memset(dnd, 0, sizeof *dnd);
 521
 522         dnd->window = window_create(display, 400, 400);
 523         window_set_title(dnd->window, "Wayland Drag and Drop Demo");
 524
 525         dnd->display = display;
 526         dnd->key = 100;
 527
 528         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 529                 x = (i % 4) * (item_width + item_padding) + item_padding;
 530                 y = (i / 4) * (item_height + item_padding) + item_padding;
 531                 if ((i ^ (i >> 2)) & 1)
 532                         dnd->items[i] = item_create(display, x, y, 0);
 533                 else
 534                         dnd->items[i] = NULL;
 535         }
 536
 537         window_set_user_data(dnd->window, dnd);
 538         window_set_redraw_handler(dnd->window, redraw_handler);
 539         window_set_keyboard_focus_handler(dnd->window,
 540                                           keyboard_focus_handler);
 541         window_set_data_handler(dnd->window, dnd_data_handler);
 542         window_set_drop_handler(dnd->window, dnd_drop_handler);
 543
 544         widget = window_get_widget(dnd->window);
 545         widget_set_enter_handler(widget, dnd_enter_handler);
 546         widget_set_motion_handler(widget, dnd_motion_handler);
 547         widget_set_button_handler(widget, dnd_button_handler);
 548
 549         width = 4 * (item_width + item_padding) + item_padding;
 550         height = 4 * (item_height + item_padding) + item_padding;
 551         window_set_child_size(dnd->window, width, height);
 552
 553         dnd_draw(dnd);
 554
 555         return dnd;
 556 }
 557
 558 int
 559 main(int argc, char *argv[])
 560 {
 561         struct display *d;
 562
 563         d = display_create(&argc, &argv, NULL);
 564         if (d == NULL) {
 565                 fprintf(stderr, "failed to create display: %m\n");
 566                 return -1;
 567         }
 568
 569         dnd_create(d);
 570
 571         display_run(d);
 572
 573         return 0;
 574 }