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