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 "config.h"
  24
  25 #include <assert.h>
  26 #include <stdint.h>
  27 #include <stdio.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <fcntl.h>
  31 #include <unistd.h>
  32 #include <math.h>
  33 #include <sys/time.h>
  34 #include <cairo.h>
  35 #include <sys/epoll.h>
  36
  37 #include <wayland-client.h>
  38 #include <wayland-cursor.h>
  39
  40 #include "window.h"
  41 #include "../shared/cairo-util.h"
  42
  43 struct dnd_drag;
  44
  45 struct dnd {
  46         struct window *window;
  47         struct widget *widget;
  48         struct display *display;
  49         uint32_t key;
  50         struct item *items[16];
  51         int self_only;
  52         struct dnd_drag *current_drag;
  53 };
  54
  55 struct dnd_drag {
  56         cairo_surface_t *translucent;
  57         cairo_surface_t *opaque;
  58         int hotspot_x, hotspot_y;
  59         struct dnd *dnd;
  60         struct input *input;
  61         uint32_t time;
  62         struct item *item;
  63         int x_offset, y_offset;
  64         int width, height;
  65         const char *mime_type;
  66
  67         struct wl_surface *drag_surface;
  68         struct wl_data_source *data_source;
  69 };
  70
  71 struct item {
  72         cairo_surface_t *surface;
  73         int seed;
  74         int x, y;
  75 };
  76
  77 struct dnd_flower_message {
  78         int seed, x_offset, y_offset;
  79 };
  80
  81
  82 static const int item_width = 64;
  83 static const int item_height = 64;
  84 static const int item_padding = 16;
  85
  86 static const char flower_mime_type[] = "application/x-wayland-dnd-flower";
  87 static const char text_mime_type[] = "text/plain;charset=utf-8";
  88
  89 static struct item *
  90 item_create(struct display *display, int x, int y, int seed)
  91 {
  92         struct item *item;
  93         struct timeval tv;
  94
  95         item = malloc(sizeof *item);
  96         if (item == NULL)
  97                 return NULL;
  98
  99
 100         gettimeofday(&tv, NULL);
 101         item->seed = seed ? seed : tv.tv_usec;
 102         srandom(item->seed);
 103
 104         const int petal_count = 3 + random() % 5;
 105         const double r1 = 20 + random() % 10;
 106         const double r2 = 5 + random() % 12;
 107         const double u = (10 + random() % 90) / 100.0;
 108         const double v = (random() % 90) / 100.0;
 109
 110         cairo_t *cr;
 111         int i;
 112         double t, dt = 2 * M_PI / (petal_count * 2);
 113         double x1, y1, x2, y2, x3, y3;
 114         struct rectangle rect;
 115
 116
 117         rect.width = item_width;
 118         rect.height = item_height;
 119         item->surface =
 120                 display_create_surface(display, NULL, &rect, SURFACE_SHM);
 121
 122         item->x = x;
 123         item->y = y;
 124
 125         cr = cairo_create(item->surface);
 126         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 127         cairo_set_source_rgba(cr, 0, 0, 0, 0);
 128         cairo_paint(cr);
 129
 130         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 131         cairo_translate(cr, item_width / 2, item_height / 2);
 132         t = random();
 133         cairo_move_to(cr, cos(t) * r1, sin(t) * r1);
 134         for (i = 0; i < petal_count; i++, t += dt * 2) {
 135                 x1 = cos(t) * r1;
 136                 y1 = sin(t) * r1;
 137                 x2 = cos(t + dt) * r2;
 138                 y2 = sin(t + dt) * r2;
 139                 x3 = cos(t + 2 * dt) * r1;
 140                 y3 = sin(t + 2 * dt) * r1;
 141
 142                 cairo_curve_to(cr,
 143                                x1 - y1 * u, y1 + x1 * u,
 144                                x2 + y2 * v, y2 - x2 * v,
 145                                x2, y2);
 146
 147                 cairo_curve_to(cr,
 148                                x2 - y2 * v, y2 + x2 * v,
 149                                x3 + y3 * u, y3 - x3 * u,
 150                                x3, y3);
 151         }
 152
 153         cairo_close_path(cr);
 154
 155         cairo_set_source_rgba(cr,
 156                               0.5 + (random() % 50) / 49.0,
 157                               0.5 + (random() % 50) / 49.0,
 158                               0.5 + (random() % 50) / 49.0,
 159                               0.5 + (random() % 100) / 99.0);
 160
 161         cairo_fill_preserve(cr);
 162
 163         cairo_set_line_width(cr, 1);
 164         cairo_set_source_rgba(cr,
 165                               0.5 + (random() % 50) / 49.0,
 166                               0.5 + (random() % 50) / 49.0,
 167                               0.5 + (random() % 50) / 49.0,
 168                               0.5 + (random() % 100) / 99.0);
 169         cairo_stroke(cr);
 170
 171         cairo_destroy(cr);
 172
 173         return item;
 174 }
 175
 176 static void
 177 dnd_redraw_handler(struct widget *widget, void *data)
 178 {
 179         struct dnd *dnd = data;
 180         struct rectangle allocation;
 181         cairo_t *cr;
 182         cairo_surface_t *surface;
 183         unsigned int i;
 184
 185         surface = window_get_surface(dnd->window);
 186         cr = cairo_create(surface);
 187         widget_get_allocation(dnd->widget, &allocation);
 188         cairo_rectangle(cr, allocation.x, allocation.y,
 189                         allocation.width, allocation.height);
 190
 191         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 192         cairo_set_source_rgba(cr, 0, 0, 0, 0.8);
 193         cairo_fill(cr);
 194
 195         cairo_rectangle(cr, allocation.x, allocation.y,
 196                         allocation.width, allocation.height);
 197         cairo_clip(cr);
 198         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 199         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 200                 if (!dnd->items[i])
 201                         continue;
 202                 cairo_set_source_surface(cr, dnd->items[i]->surface,
 203                                          dnd->items[i]->x + allocation.x,
 204                                          dnd->items[i]->y + allocation.y);
 205                 cairo_paint(cr);
 206         }
 207
 208         cairo_destroy(cr);
 209         cairo_surface_destroy(surface);
 210 }
 211
 212 static void
 213 keyboard_focus_handler(struct window *window,
 214                        struct input *device, void *data)
 215 {
 216         struct dnd *dnd = data;
 217
 218         window_schedule_redraw(dnd->window);
 219 }
 220
 221 static int
 222 dnd_add_item(struct dnd *dnd, struct item *item)
 223 {
 224         unsigned int i;
 225
 226         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 227                 if (dnd->items[i] == 0) {
 228                         dnd->items[i] = item;
 229                         return i;
 230                 }
 231         }
 232         return -1;
 233 }
 234
 235 static struct item *
 236 dnd_get_item(struct dnd *dnd, int32_t x, int32_t y)
 237 {
 238         struct item *item;
 239         struct rectangle allocation;
 240         unsigned int i;
 241
 242         widget_get_allocation(dnd->widget, &allocation);
 243
 244         x -= allocation.x;
 245         y -= allocation.y;
 246
 247         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 248                 item = dnd->items[i];
 249                 if (item &&
 250                     item->x <= x && x < item->x + item_width &&
 251                     item->y <= y && y < item->y + item_height)
 252                         return item;
 253         }
 254
 255         return NULL;
 256 }
 257
 258 static void
 259 data_source_target(void *data,
 260                    struct wl_data_source *source, const char *mime_type)
 261 {
 262         struct dnd_drag *dnd_drag = data;
 263         struct dnd *dnd = dnd_drag->dnd;
 264         cairo_surface_t *surface;
 265         struct wl_buffer *buffer;
 266
 267         dnd_drag->mime_type = mime_type;
 268         if (mime_type)
 269                 surface = dnd_drag->opaque;
 270         else
 271                 surface = dnd_drag->translucent;
 272
 273         buffer = display_get_buffer_for_surface(dnd->display, surface);
 274         wl_surface_attach(dnd_drag->drag_surface, buffer, 0, 0);
 275         wl_surface_damage(dnd_drag->drag_surface, 0, 0,
 276                           dnd_drag->width, dnd_drag->height);
 277         wl_surface_commit(dnd_drag->drag_surface);
 278 }
 279
 280 static void
 281 data_source_send(void *data, struct wl_data_source *source,
 282                  const char *mime_type, int32_t fd)
 283 {
 284         struct dnd_flower_message dnd_flower_message;
 285         struct dnd_drag *dnd_drag = data;
 286         char buffer[128];
 287         int n;
 288
 289         if (strcmp(mime_type, flower_mime_type) == 0) {
 290                 dnd_flower_message.seed = dnd_drag->item->seed;
 291                 dnd_flower_message.x_offset = dnd_drag->x_offset;
 292                 dnd_flower_message.y_offset = dnd_drag->y_offset;
 293
 294                 if (write(fd, &dnd_flower_message,
 295                           sizeof dnd_flower_message) < 0)
 296                         abort();
 297         } else if (strcmp(mime_type, text_mime_type) == 0) {
 298                 n = snprintf(buffer, sizeof buffer, "seed=%d x=%d y=%d\n",
 299                              dnd_drag->item->seed,
 300                              dnd_drag->x_offset,
 301                              dnd_drag->y_offset);
 302
 303                 if (write(fd, buffer, n) < 0)
 304                         abort();
 305         }
 306
 307         close(fd);
 308 }
 309
 310 static void
 311 data_source_cancelled(void *data, struct wl_data_source *source)
 312 {
 313         struct dnd_drag *dnd_drag = data;
 314
 315         /* The 'cancelled' event means that the source is no longer in
 316          * use by the drag (or current selection).  We need to clean
 317          * up the drag object created and the local state. */
 318
 319         wl_data_source_destroy(dnd_drag->data_source);
 320
 321         /* Destroy the item that has been dragged out */
 322         cairo_surface_destroy(dnd_drag->item->surface);
 323         free(dnd_drag->item);
 324
 325         wl_surface_destroy(dnd_drag->drag_surface);
 326
 327         cairo_surface_destroy(dnd_drag->translucent);
 328         cairo_surface_destroy(dnd_drag->opaque);
 329         free(dnd_drag);
 330 }
 331
 332 static const struct wl_data_source_listener data_source_listener = {
 333         data_source_target,
 334         data_source_send,
 335         data_source_cancelled
 336 };
 337
 338 static cairo_surface_t *
 339 create_drag_icon(struct dnd_drag *dnd_drag,
 340                  struct item *item, int32_t x, int32_t y, double opacity)
 341 {
 342         struct dnd *dnd = dnd_drag->dnd;
 343         cairo_surface_t *surface;
 344         struct rectangle rectangle;
 345         cairo_pattern_t *pattern;
 346         cairo_t *cr;
 347
 348         rectangle.width = item_width;
 349         rectangle.height = item_height;
 350         surface = display_create_surface(dnd->display, NULL, &rectangle,
 351                                          SURFACE_SHM);
 352
 353         cr = cairo_create(surface);
 354         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 355         cairo_set_source_surface(cr, item->surface, 0, 0);
 356         pattern = cairo_pattern_create_rgba(0, 0, 0, opacity);
 357         cairo_mask(cr, pattern);
 358         cairo_pattern_destroy(pattern);
 359
 360         cairo_destroy(cr);
 361
 362         dnd_drag->hotspot_x = x - item->x;
 363         dnd_drag->hotspot_y = y - item->y;
 364         dnd_drag->width = rectangle.width;
 365         dnd_drag->height = rectangle.height;
 366
 367         return surface;
 368 }
 369
 370 static int
 371 create_drag_source(struct dnd *dnd,
 372                 struct input *input, uint32_t time,
 373                 int32_t x, int32_t y)
 374 {
 375         struct item *item;
 376         struct rectangle allocation;
 377         struct dnd_drag *dnd_drag;
 378         struct display *display;
 379         struct wl_compositor *compositor;
 380         struct wl_buffer *buffer;
 381         unsigned int i;
 382         uint32_t serial;
 383         cairo_surface_t *icon;
 384
 385         widget_get_allocation(dnd->widget, &allocation);
 386         item = dnd_get_item(dnd, x, y);
 387         x -= allocation.x;
 388         y -= allocation.y;
 389
 390         if (item) {
 391                 dnd_drag = xmalloc(sizeof *dnd_drag);
 392                 dnd_drag->dnd = dnd;
 393                 dnd_drag->input = input;
 394                 dnd_drag->time = time;
 395                 dnd_drag->item = item;
 396                 dnd_drag->x_offset = x - item->x;
 397                 dnd_drag->y_offset = y - item->y;
 398
 399                 for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 400                         if (item == dnd->items[i]){
 401                                 dnd->items[i] = 0;
 402                                 break;
 403                         }
 404                 }
 405
 406                 display = window_get_display(dnd->window);
 407                 compositor = display_get_compositor(display);
 408                 serial = display_get_serial(display);
 409                 dnd_drag->drag_surface =
 410                         wl_compositor_create_surface(compositor);
 411
 412                 if (dnd->self_only) {
 413                         dnd_drag->data_source = NULL;
 414                 } else {
 415                         dnd_drag->data_source =
 416                                 display_create_data_source(dnd->display);
 417                         wl_data_source_add_listener(dnd_drag->data_source,
 418                                                     &data_source_listener,
 419                                                     dnd_drag);
 420                         wl_data_source_offer(dnd_drag->data_source,
 421                                              flower_mime_type);
 422                         wl_data_source_offer(dnd_drag->data_source,
 423                                              text_mime_type);
 424                 }
 425
 426                 wl_data_device_start_drag(input_get_data_device(input),
 427                                           dnd_drag->data_source,
 428                                           window_get_wl_surface(dnd->window),
 429                                           dnd_drag->drag_surface,
 430                                           serial);
 431
 432                 dnd_drag->opaque =
 433                         create_drag_icon(dnd_drag, item, x, y, 1);
 434                 dnd_drag->translucent =
 435                         create_drag_icon(dnd_drag, item, x, y, 0.2);
 436
 437                 if (dnd->self_only)
 438                         icon = dnd_drag->opaque;
 439                 else
 440                         icon = dnd_drag->translucent;
 441
 442                 buffer = display_get_buffer_for_surface(dnd->display, icon);
 443                 wl_surface_attach(dnd_drag->drag_surface, buffer,
 444                                   -dnd_drag->hotspot_x, -dnd_drag->hotspot_y);
 445                 wl_surface_damage(dnd_drag->drag_surface, 0, 0,
 446                                   dnd_drag->width, dnd_drag->height);
 447                 wl_surface_commit(dnd_drag->drag_surface);
 448
 449                 dnd->current_drag = dnd_drag;
 450                 window_schedule_redraw(dnd->window);
 451
 452                 return 0;
 453         } else
 454                 return -1;
 455 }
 456
 457 static void
 458 dnd_button_handler(struct widget *widget,
 459                    struct input *input, uint32_t time,
 460                    uint32_t button, enum wl_pointer_button_state state,
 461                    void *data)
 462 {
 463         struct dnd *dnd = data;
 464         int32_t x, y;
 465
 466         input_get_position(input, &x, &y);
 467         if (state == WL_POINTER_BUTTON_STATE_PRESSED) {
 468                 input_ungrab(input);
 469                 if (create_drag_source(dnd, input, time, x, y) == 0)
 470                         input_set_pointer_image(input, CURSOR_DRAGGING);
 471         }
 472 }
 473
 474 static void
 475 dnd_touch_down_handler(struct widget *widget,
 476                 struct input *input, uint32_t serial,
 477                 uint32_t time, int32_t id,
 478                 float x, float y, void *data)
 479 {
 480         struct dnd *dnd = data;
 481         int32_t int_x, int_y;
 482
 483         if (id > 0)
 484                 return;
 485
 486         int_x = (int32_t)x;
 487         int_y = (int32_t)y;
 488         if (create_drag_source(dnd, input, time, int_x, int_y) == 0)
 489                 touch_grab(input, 0);
 490 }
 491
 492 static int
 493 lookup_cursor(struct dnd *dnd, int x, int y)
 494 {
 495         struct item *item;
 496
 497         item = dnd_get_item(dnd, x, y);
 498         if (item)
 499                 return CURSOR_HAND1;
 500         else
 501                 return CURSOR_LEFT_PTR;
 502 }
 503
 504 static int
 505 dnd_enter_handler(struct widget *widget,
 506                   struct input *input, float x, float y, void *data)
 507 {
 508         struct dnd *dnd = data;
 509
 510         dnd->current_drag = NULL;
 511
 512         return lookup_cursor(dnd, x, y);
 513 }
 514
 515 static int
 516 dnd_motion_handler(struct widget *widget,
 517                    struct input *input, uint32_t time,
 518                    float x, float y, void *data)
 519 {
 520         return lookup_cursor(data, x, y);
 521 }
 522
 523 static void
 524 dnd_data_handler(struct window *window,
 525                  struct input *input,
 526                  float x, float y, const char **types, void *data)
 527 {
 528         struct dnd *dnd = data;
 529         int i, has_flower = 0;
 530
 531         if (!types)
 532                 return;
 533         for (i = 0; types[i]; i++)
 534                 if (strcmp(types[i], flower_mime_type) == 0)
 535                         has_flower = 1;
 536
 537         if (dnd_get_item(dnd, x, y) || dnd->self_only || !has_flower) {
 538                 input_accept(input, NULL);
 539         } else {
 540                 input_accept(input, flower_mime_type);
 541         }
 542 }
 543
 544 static void
 545 dnd_receive_func(void *data, size_t len, int32_t x, int32_t y, void *user_data)
 546 {
 547         struct dnd *dnd = user_data;
 548         struct dnd_flower_message *message = data;
 549         struct item *item;
 550         struct rectangle allocation;
 551
 552         if (len == 0) {
 553                 return;
 554         } else if (len != sizeof *message) {
 555                 fprintf(stderr, "odd message length %zu, expected %zu\n",
 556                         len, sizeof *message);
 557                 return;
 558         }
 559
 560         widget_get_allocation(dnd->widget, &allocation);
 561         item = item_create(dnd->display,
 562                            x - message->x_offset - allocation.x,
 563                            y - message->y_offset - allocation.y,
 564                            message->seed);
 565
 566         dnd_add_item(dnd, item);
 567         window_schedule_redraw(dnd->window);
 568 }
 569
 570 static void
 571 dnd_drop_handler(struct window *window, struct input *input,
 572                  int32_t x, int32_t y, void *data)
 573 {
 574         struct dnd *dnd = data;
 575         struct dnd_flower_message message;
 576
 577         if (dnd_get_item(dnd, x, y)) {
 578                 fprintf(stderr, "got 'drop', but no target\n");
 579                 return;
 580         }
 581
 582         if (!dnd->self_only) {
 583                 input_receive_drag_data(input,
 584                                         flower_mime_type,
 585                                         dnd_receive_func, dnd);
 586         } else if (dnd->current_drag) {
 587                 message.seed = dnd->current_drag->item->seed;
 588                 message.x_offset = dnd->current_drag->x_offset;
 589                 message.y_offset = dnd->current_drag->y_offset;
 590                 dnd_receive_func(&message, sizeof message, x, y, dnd);
 591                 dnd->current_drag = NULL;
 592         } else {
 593                 fprintf(stderr, "ignoring drop from another client\n");
 594         }
 595 }
 596
 597 static struct dnd *
 598 dnd_create(struct display *display)
 599 {
 600         struct dnd *dnd;
 601         int x, y;
 602         int32_t width, height;
 603         unsigned int i;
 604
 605         dnd = xzalloc(sizeof *dnd);
 606         dnd->window = window_create(display);
 607         dnd->widget = window_frame_create(dnd->window, dnd);
 608         window_set_title(dnd->window, "Wayland Drag and Drop Demo");
 609
 610         dnd->display = display;
 611         dnd->key = 100;
 612
 613         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 614                 x = (i % 4) * (item_width + item_padding) + item_padding;
 615                 y = (i / 4) * (item_height + item_padding) + item_padding;
 616                 if ((i ^ (i >> 2)) & 1)
 617                         dnd->items[i] = item_create(display, x, y, 0);
 618                 else
 619                         dnd->items[i] = NULL;
 620         }
 621
 622         window_set_user_data(dnd->window, dnd);
 623         window_set_keyboard_focus_handler(dnd->window,
 624                                           keyboard_focus_handler);
 625         window_set_data_handler(dnd->window, dnd_data_handler);
 626         window_set_drop_handler(dnd->window, dnd_drop_handler);
 627
 628         widget_set_redraw_handler(dnd->widget, dnd_redraw_handler);
 629         widget_set_enter_handler(dnd->widget, dnd_enter_handler);
 630         widget_set_motion_handler(dnd->widget, dnd_motion_handler);
 631         widget_set_button_handler(dnd->widget, dnd_button_handler);
 632         widget_set_touch_down_handler(dnd->widget, dnd_touch_down_handler);
 633
 634         width = 4 * (item_width + item_padding) + item_padding;
 635         height = 4 * (item_height + item_padding) + item_padding;
 636
 637         window_frame_set_child_size(dnd->widget, width, height);
 638
 639         return dnd;
 640 }
 641
 642 static void
 643 dnd_destroy(struct dnd *dnd)
 644 {
 645         widget_destroy(dnd->widget);
 646         window_destroy(dnd->window);
 647         free(dnd);
 648 }
 649
 650 int
 651 main(int argc, char *argv[])
 652 {
 653         struct display *d;
 654         struct dnd *dnd;
 655         int self_only = 0;
 656
 657         if (argc == 2 && !strcmp(argv[1], "--self-only"))
 658                 self_only = 1;
 659         else if (argc > 1) {
 660                 printf("Usage: %s [OPTIONS]\n  --self-only\n", argv[0]);
 661                 return 1;
 662         }
 663
 664         d = display_create(&argc, argv);
 665         if (d == NULL) {
 666                 fprintf(stderr, "failed to create display: %m\n");
 667                 return -1;
 668         }
 669
 670         dnd = dnd_create(d);
 671         if (self_only)
 672                 dnd->self_only = 1;
 673
 674         display_run(d);
 675
 676         dnd_destroy(dnd);
 677         display_destroy(d);
 678
 679         return 0;
 680 }