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 <assert.h>
  24 #include <stdint.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <string.h>
  28 #include <fcntl.h>
  29 #include <unistd.h>
  30 #include <math.h>
  31 #include <sys/time.h>
  32 #include <cairo.h>
  33 #include <sys/epoll.h>
  34
  35 #include <wayland-client.h>
  36 #include <wayland-cursor.h>
  37
  38 #include "window.h"
  39 #include "../shared/cairo-util.h"
  40
  41 struct dnd_drag;
  42
  43 struct dnd {
  44         struct window *window;
  45         struct widget *widget;
  46         struct display *display;
  47         uint32_t key;
  48         struct item *items[16];
  49         int self_only;
  50         struct dnd_drag *current_drag;
  51 };
  52
  53 struct dnd_drag {
  54         cairo_surface_t *translucent;
  55         cairo_surface_t *opaque;
  56         int hotspot_x, hotspot_y;
  57         struct dnd *dnd;
  58         struct input *input;
  59         uint32_t time;
  60         struct item *item;
  61         int x_offset, y_offset;
  62         int width, height;
  63         const char *mime_type;
  64
  65         struct wl_surface *drag_surface;
  66         struct wl_data_source *data_source;
  67 };
  68
  69 struct item {
  70         cairo_surface_t *surface;
  71         int seed;
  72         int x, y;
  73 };
  74
  75 struct dnd_flower_message {
  76         int seed, x_offset, y_offset;
  77 };
  78
  79
  80 static const int item_width = 64;
  81 static const int item_height = 64;
  82 static const int item_padding = 16;
  83
  84 static const char flower_mime_type[] = "application/x-wayland-dnd-flower";
  85 static const char text_mime_type[] = "text/plain;charset=utf-8";
  86
  87 static struct item *
  88 item_create(struct display *display, int x, int y, int seed)
  89 {
  90         struct item *item;
  91         struct timeval tv;
  92
  93         item = malloc(sizeof *item);
  94         if (item == NULL)
  95                 return NULL;
  96
  97
  98         gettimeofday(&tv, NULL);
  99         item->seed = seed ? seed : tv.tv_usec;
 100         srandom(item->seed);
 101
 102         const int petal_count = 3 + random() % 5;
 103         const double r1 = 20 + random() % 10;
 104         const double r2 = 5 + random() % 12;
 105         const double u = (10 + random() % 90) / 100.0;
 106         const double v = (random() % 90) / 100.0;
 107
 108         cairo_t *cr;
 109         int i;
 110         double t, dt = 2 * M_PI / (petal_count * 2);
 111         double x1, y1, x2, y2, x3, y3;
 112         struct rectangle rect;
 113
 114
 115         rect.width = item_width;
 116         rect.height = item_height;
 117         item->surface =
 118                 display_create_surface(display, NULL, &rect, SURFACE_SHM);
 119
 120         item->x = x;
 121         item->y = y;
 122
 123         cr = cairo_create(item->surface);
 124         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 125         cairo_set_source_rgba(cr, 0, 0, 0, 0);
 126         cairo_paint(cr);
 127
 128         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 129         cairo_translate(cr, item_width / 2, item_height / 2);
 130         t = random();
 131         cairo_move_to(cr, cos(t) * r1, sin(t) * r1);
 132         for (i = 0; i < petal_count; i++, t += dt * 2) {
 133                 x1 = cos(t) * r1;
 134                 y1 = sin(t) * r1;
 135                 x2 = cos(t + dt) * r2;
 136                 y2 = sin(t + dt) * r2;
 137                 x3 = cos(t + 2 * dt) * r1;
 138                 y3 = sin(t + 2 * dt) * r1;
 139
 140                 cairo_curve_to(cr,
 141                                x1 - y1 * u, y1 + x1 * u,
 142                                x2 + y2 * v, y2 - x2 * v,
 143                                x2, y2);
 144
 145                 cairo_curve_to(cr,
 146                                x2 - y2 * v, y2 + x2 * v,
 147                                x3 + y3 * u, y3 - x3 * u,
 148                                x3, y3);
 149         }
 150
 151         cairo_close_path(cr);
 152
 153         cairo_set_source_rgba(cr,
 154                               0.5 + (random() % 50) / 49.0,
 155                               0.5 + (random() % 50) / 49.0,
 156                               0.5 + (random() % 50) / 49.0,
 157                               0.5 + (random() % 100) / 99.0);
 158
 159         cairo_fill_preserve(cr);
 160
 161         cairo_set_line_width(cr, 1);
 162         cairo_set_source_rgba(cr,
 163                               0.5 + (random() % 50) / 49.0,
 164                               0.5 + (random() % 50) / 49.0,
 165                               0.5 + (random() % 50) / 49.0,
 166                               0.5 + (random() % 100) / 99.0);
 167         cairo_stroke(cr);
 168
 169         cairo_destroy(cr);
 170
 171         return item;
 172 }
 173
 174 static void
 175 dnd_redraw_handler(struct widget *widget, void *data)
 176 {
 177         struct dnd *dnd = data;
 178         struct rectangle allocation;
 179         cairo_t *cr;
 180         cairo_surface_t *surface;
 181         unsigned int i;
 182
 183         surface = window_get_surface(dnd->window);
 184         cr = cairo_create(surface);
 185         widget_get_allocation(dnd->widget, &allocation);
 186         cairo_rectangle(cr, allocation.x, allocation.y,
 187                         allocation.width, allocation.height);
 188
 189         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 190         cairo_set_source_rgba(cr, 0, 0, 0, 0.8);
 191         cairo_fill(cr);
 192
 193         cairo_rectangle(cr, allocation.x, allocation.y,
 194                         allocation.width, allocation.height);
 195         cairo_clip(cr);
 196         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 197         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 198                 if (!dnd->items[i])
 199                         continue;
 200                 cairo_set_source_surface(cr, dnd->items[i]->surface,
 201                                          dnd->items[i]->x + allocation.x,
 202                                          dnd->items[i]->y + allocation.y);
 203                 cairo_paint(cr);
 204         }
 205
 206         cairo_destroy(cr);
 207         cairo_surface_destroy(surface);
 208 }
 209
 210 static void
 211 keyboard_focus_handler(struct window *window,
 212                        struct input *device, void *data)
 213 {
 214         struct dnd *dnd = data;
 215
 216         window_schedule_redraw(dnd->window);
 217 }
 218
 219 static int
 220 dnd_add_item(struct dnd *dnd, struct item *item)
 221 {
 222         unsigned int i;
 223
 224         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 225                 if (dnd->items[i] == 0) {
 226                         dnd->items[i] = item;
 227                         return i;
 228                 }
 229         }
 230         return -1;
 231 }
 232
 233 static struct item *
 234 dnd_get_item(struct dnd *dnd, int32_t x, int32_t y)
 235 {
 236         struct item *item;
 237         struct rectangle allocation;
 238         unsigned int i;
 239
 240         widget_get_allocation(dnd->widget, &allocation);
 241
 242         x -= allocation.x;
 243         y -= allocation.y;
 244
 245         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 246                 item = dnd->items[i];
 247                 if (item &&
 248                     item->x <= x && x < item->x + item_width &&
 249                     item->y <= y && y < item->y + item_height)
 250                         return item;
 251         }
 252
 253         return NULL;
 254 }
 255
 256 static void
 257 data_source_target(void *data,
 258                    struct wl_data_source *source, const char *mime_type)
 259 {
 260         struct dnd_drag *dnd_drag = data;
 261         struct dnd *dnd = dnd_drag->dnd;
 262         cairo_surface_t *surface;
 263         struct wl_buffer *buffer;
 264
 265         dnd_drag->mime_type = mime_type;
 266         if (mime_type)
 267                 surface = dnd_drag->opaque;
 268         else
 269                 surface = dnd_drag->translucent;
 270
 271         buffer = display_get_buffer_for_surface(dnd->display, surface);
 272         wl_surface_attach(dnd_drag->drag_surface, buffer, 0, 0);
 273         wl_surface_damage(dnd_drag->drag_surface, 0, 0,
 274                           dnd_drag->width, dnd_drag->height);
 275         wl_surface_commit(dnd_drag->drag_surface);
 276 }
 277
 278 static void
 279 data_source_send(void *data, struct wl_data_source *source,
 280                  const char *mime_type, int32_t fd)
 281 {
 282         struct dnd_flower_message dnd_flower_message;
 283         struct dnd_drag *dnd_drag = data;
 284         char buffer[128];
 285         int n;
 286
 287         if (strcmp(mime_type, flower_mime_type) == 0) {
 288                 dnd_flower_message.seed = dnd_drag->item->seed;
 289                 dnd_flower_message.x_offset = dnd_drag->x_offset;
 290                 dnd_flower_message.y_offset = dnd_drag->y_offset;
 291
 292                 if (write(fd, &dnd_flower_message,
 293                           sizeof dnd_flower_message) < 0)
 294                         abort();
 295         } else if (strcmp(mime_type, text_mime_type) == 0) {
 296                 n = snprintf(buffer, sizeof buffer, "seed=%d x=%d y=%d\n",
 297                              dnd_drag->item->seed,
 298                              dnd_drag->x_offset,
 299                              dnd_drag->y_offset);
 300
 301                 if (write(fd, buffer, n) < 0)
 302                         abort();
 303         }
 304
 305         close(fd);
 306 }
 307
 308 static void
 309 data_source_cancelled(void *data, struct wl_data_source *source)
 310 {
 311         struct dnd_drag *dnd_drag = data;
 312
 313         /* The 'cancelled' event means that the source is no longer in
 314          * use by the drag (or current selection).  We need to clean
 315          * up the drag object created and the local state. */
 316
 317         wl_data_source_destroy(dnd_drag->data_source);
 318
 319         /* Destroy the item that has been dragged out */
 320         cairo_surface_destroy(dnd_drag->item->surface);
 321         free(dnd_drag->item);
 322
 323         wl_surface_destroy(dnd_drag->drag_surface);
 324
 325         cairo_surface_destroy(dnd_drag->translucent);
 326         cairo_surface_destroy(dnd_drag->opaque);
 327         free(dnd_drag);
 328 }
 329
 330 static const struct wl_data_source_listener data_source_listener = {
 331         data_source_target,
 332         data_source_send,
 333         data_source_cancelled
 334 };
 335
 336 static cairo_surface_t *
 337 create_drag_icon(struct dnd_drag *dnd_drag,
 338                  struct item *item, int32_t x, int32_t y, double opacity)
 339 {
 340         struct dnd *dnd = dnd_drag->dnd;
 341         cairo_surface_t *surface;
 342         struct rectangle rectangle;
 343         cairo_pattern_t *pattern;
 344         cairo_t *cr;
 345
 346         rectangle.width = item_width;
 347         rectangle.height = item_height;
 348         surface = display_create_surface(dnd->display, NULL, &rectangle,
 349                                          SURFACE_SHM);
 350
 351         cr = cairo_create(surface);
 352         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 353         cairo_set_source_surface(cr, item->surface, 0, 0);
 354         pattern = cairo_pattern_create_rgba(0, 0, 0, opacity);
 355         cairo_mask(cr, pattern);
 356         cairo_pattern_destroy(pattern);
 357
 358         cairo_destroy(cr);
 359
 360         dnd_drag->hotspot_x = x - item->x;
 361         dnd_drag->hotspot_y = y - item->y;
 362         dnd_drag->width = rectangle.width;
 363         dnd_drag->height = rectangle.height;
 364
 365         return surface;
 366 }
 367
 368 static int
 369 create_drag_source(struct dnd *dnd,
 370                 struct input *input, uint32_t time,
 371                 int32_t x, int32_t y)
 372 {
 373         struct item *item;
 374         struct rectangle allocation;
 375         struct dnd_drag *dnd_drag;
 376         struct display *display;
 377         struct wl_compositor *compositor;
 378         struct wl_buffer *buffer;
 379         unsigned int i;
 380         uint32_t serial;
 381         cairo_surface_t *icon;
 382
 383         widget_get_allocation(dnd->widget, &allocation);
 384         item = dnd_get_item(dnd, x, y);
 385         x -= allocation.x;
 386         y -= allocation.y;
 387
 388         if (item) {
 389                 dnd_drag = xmalloc(sizeof *dnd_drag);
 390                 dnd_drag->dnd = dnd;
 391                 dnd_drag->input = input;
 392                 dnd_drag->time = time;
 393                 dnd_drag->item = item;
 394                 dnd_drag->x_offset = x - item->x;
 395                 dnd_drag->y_offset = y - item->y;
 396
 397                 for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 398                         if (item == dnd->items[i]){
 399                                 dnd->items[i] = 0;
 400                                 break;
 401                         }
 402                 }
 403
 404                 display = window_get_display(dnd->window);
 405                 compositor = display_get_compositor(display);
 406                 serial = display_get_serial(display);
 407                 dnd_drag->drag_surface =
 408                         wl_compositor_create_surface(compositor);
 409
 410                 if (dnd->self_only) {
 411                         dnd_drag->data_source = NULL;
 412                 } else {
 413                         dnd_drag->data_source =
 414                                 display_create_data_source(dnd->display);
 415                         wl_data_source_add_listener(dnd_drag->data_source,
 416                                                     &data_source_listener,
 417                                                     dnd_drag);
 418                         wl_data_source_offer(dnd_drag->data_source,
 419                                              flower_mime_type);
 420                         wl_data_source_offer(dnd_drag->data_source,
 421                                              text_mime_type);
 422                 }
 423
 424                 wl_data_device_start_drag(input_get_data_device(input),
 425                                           dnd_drag->data_source,
 426                                           window_get_wl_surface(dnd->window),
 427                                           dnd_drag->drag_surface,
 428                                           serial);
 429
 430                 dnd_drag->opaque =
 431                         create_drag_icon(dnd_drag, item, x, y, 1);
 432                 dnd_drag->translucent =
 433                         create_drag_icon(dnd_drag, item, x, y, 0.2);
 434
 435                 if (dnd->self_only)
 436                         icon = dnd_drag->opaque;
 437                 else
 438                         icon = dnd_drag->translucent;
 439
 440                 buffer = display_get_buffer_for_surface(dnd->display, icon);
 441                 wl_surface_attach(dnd_drag->drag_surface, buffer,
 442                                   -dnd_drag->hotspot_x, -dnd_drag->hotspot_y);
 443                 wl_surface_damage(dnd_drag->drag_surface, 0, 0,
 444                                   dnd_drag->width, dnd_drag->height);
 445                 wl_surface_commit(dnd_drag->drag_surface);
 446
 447                 dnd->current_drag = dnd_drag;
 448                 window_schedule_redraw(dnd->window);
 449
 450                 return 0;
 451         } else
 452                 return -1;
 453 }
 454
 455 static void
 456 dnd_button_handler(struct widget *widget,
 457                    struct input *input, uint32_t time,
 458                    uint32_t button, enum wl_pointer_button_state state,
 459                    void *data)
 460 {
 461         struct dnd *dnd = data;
 462         int32_t x, y;
 463
 464         input_get_position(input, &x, &y);
 465         if (state == WL_POINTER_BUTTON_STATE_PRESSED) {
 466                 input_ungrab(input);
 467                 if (create_drag_source(dnd, input, time, x, y) == 0)
 468                         input_set_pointer_image(input, CURSOR_DRAGGING);
 469         }
 470 }
 471
 472 static void
 473 dnd_touch_down_handler(struct widget *widget,
 474                 struct input *input, uint32_t serial,
 475                 uint32_t time, int32_t id,
 476                 float x, float y, void *data)
 477 {
 478         struct dnd *dnd = data;
 479         int32_t int_x, int_y;
 480
 481         if (id > 0)
 482                 return;
 483
 484         int_x = (int32_t)x;
 485         int_y = (int32_t)y;
 486         if (create_drag_source(dnd, input, time, int_x, int_y) == 0)
 487                 touch_grab(input, 0);
 488 }
 489
 490 static int
 491 lookup_cursor(struct dnd *dnd, int x, int y)
 492 {
 493         struct item *item;
 494
 495         item = dnd_get_item(dnd, x, y);
 496         if (item)
 497                 return CURSOR_HAND1;
 498         else
 499                 return CURSOR_LEFT_PTR;
 500 }
 501
 502 static int
 503 dnd_enter_handler(struct widget *widget,
 504                   struct input *input, float x, float y, void *data)
 505 {
 506         struct dnd *dnd = data;
 507
 508         dnd->current_drag = NULL;
 509
 510         return lookup_cursor(dnd, x, y);
 511 }
 512
 513 static int
 514 dnd_motion_handler(struct widget *widget,
 515                    struct input *input, uint32_t time,
 516                    float x, float y, void *data)
 517 {
 518         return lookup_cursor(data, x, y);
 519 }
 520
 521 static void
 522 dnd_data_handler(struct window *window,
 523                  struct input *input,
 524                  float x, float y, const char **types, void *data)
 525 {
 526         struct dnd *dnd = data;
 527         int i, has_flower = 0;
 528
 529         if (!types)
 530                 return;
 531         for (i = 0; types[i]; i++)
 532                 if (strcmp(types[i], flower_mime_type) == 0)
 533                         has_flower = 1;
 534
 535         if (dnd_get_item(dnd, x, y) || dnd->self_only || !has_flower) {
 536                 input_accept(input, NULL);
 537         } else {
 538                 input_accept(input, flower_mime_type);
 539         }
 540 }
 541
 542 static void
 543 dnd_receive_func(void *data, size_t len, int32_t x, int32_t y, void *user_data)
 544 {
 545         struct dnd *dnd = user_data;
 546         struct dnd_flower_message *message = data;
 547         struct item *item;
 548         struct rectangle allocation;
 549
 550         if (len == 0) {
 551                 return;
 552         } else if (len != sizeof *message) {
 553                 fprintf(stderr, "odd message length %zu, expected %zu\n",
 554                         len, sizeof *message);
 555                 return;
 556         }
 557
 558         widget_get_allocation(dnd->widget, &allocation);
 559         item = item_create(dnd->display,
 560                            x - message->x_offset - allocation.x,
 561                            y - message->y_offset - allocation.y,
 562                            message->seed);
 563
 564         dnd_add_item(dnd, item);
 565         window_schedule_redraw(dnd->window);
 566 }
 567
 568 static void
 569 dnd_drop_handler(struct window *window, struct input *input,
 570                  int32_t x, int32_t y, void *data)
 571 {
 572         struct dnd *dnd = data;
 573         struct dnd_flower_message message;
 574
 575         if (dnd_get_item(dnd, x, y)) {
 576                 fprintf(stderr, "got 'drop', but no target\n");
 577                 return;
 578         }
 579
 580         if (!dnd->self_only) {
 581                 input_receive_drag_data(input,
 582                                         flower_mime_type,
 583                                         dnd_receive_func, dnd);
 584         } else if (dnd->current_drag) {
 585                 message.seed = dnd->current_drag->item->seed;
 586                 message.x_offset = dnd->current_drag->x_offset;
 587                 message.y_offset = dnd->current_drag->y_offset;
 588                 dnd_receive_func(&message, sizeof message, x, y, dnd);
 589                 dnd->current_drag = NULL;
 590         } else {
 591                 fprintf(stderr, "ignoring drop from another client\n");
 592         }
 593 }
 594
 595 static struct dnd *
 596 dnd_create(struct display *display)
 597 {
 598         struct dnd *dnd;
 599         int x, y;
 600         int32_t width, height;
 601         unsigned int i;
 602
 603         dnd = xzalloc(sizeof *dnd);
 604         dnd->window = window_create(display);
 605         dnd->widget = window_frame_create(dnd->window, dnd);
 606         window_set_title(dnd->window, "Wayland Drag and Drop Demo");
 607
 608         dnd->display = display;
 609         dnd->key = 100;
 610
 611         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 612                 x = (i % 4) * (item_width + item_padding) + item_padding;
 613                 y = (i / 4) * (item_height + item_padding) + item_padding;
 614                 if ((i ^ (i >> 2)) & 1)
 615                         dnd->items[i] = item_create(display, x, y, 0);
 616                 else
 617                         dnd->items[i] = NULL;
 618         }
 619
 620         window_set_user_data(dnd->window, dnd);
 621         window_set_keyboard_focus_handler(dnd->window,
 622                                           keyboard_focus_handler);
 623         window_set_data_handler(dnd->window, dnd_data_handler);
 624         window_set_drop_handler(dnd->window, dnd_drop_handler);
 625
 626         widget_set_redraw_handler(dnd->widget, dnd_redraw_handler);
 627         widget_set_enter_handler(dnd->widget, dnd_enter_handler);
 628         widget_set_motion_handler(dnd->widget, dnd_motion_handler);
 629         widget_set_button_handler(dnd->widget, dnd_button_handler);
 630         widget_set_touch_down_handler(dnd->widget, dnd_touch_down_handler);
 631
 632         width = 4 * (item_width + item_padding) + item_padding;
 633         height = 4 * (item_height + item_padding) + item_padding;
 634
 635         window_frame_set_child_size(dnd->widget, width, height);
 636
 637         return dnd;
 638 }
 639
 640 int
 641 main(int argc, char *argv[])
 642 {
 643         struct display *d;
 644         struct dnd *dnd;
 645         int i;
 646
 647         d = display_create(&argc, argv);
 648         if (d == NULL) {
 649                 fprintf(stderr, "failed to create display: %m\n");
 650                 return -1;
 651         }
 652
 653         dnd = dnd_create(d);
 654
 655         for (i = 1; i < argc; i++)
 656                 if (strcmp("--self-only", argv[i]) == 0)
 657                         dnd->self_only = 1;
 658
 659         display_run(d);
 660
 661         return 0;
 662 }