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         struct widget *widget;
  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         window_draw(dnd->window);
 171
 172         surface = window_get_surface(dnd->window);
 173         cr = cairo_create(surface);
 174         window_get_child_allocation(dnd->window, &allocation);
 175         cairo_rectangle(cr, allocation.x, allocation.y,
 176                         allocation.width, allocation.height);
 177
 178         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 179         cairo_set_source_rgba(cr, 0, 0, 0, 0.8);
 180         cairo_fill(cr);
 181
 182         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 183         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 184                 if (!dnd->items[i])
 185                         continue;
 186                 cairo_set_source_surface(cr, dnd->items[i]->surface,
 187                                          dnd->items[i]->x + allocation.x,
 188                                          dnd->items[i]->y + allocation.y);
 189                 cairo_paint(cr);
 190         }
 191
 192         cairo_destroy(cr);
 193         cairo_surface_destroy(surface);
 194         window_flush(dnd->window);
 195 }
 196
 197 static void
 198 redraw_handler(struct window *window, void *data)
 199 {
 200         struct dnd *dnd = data;
 201
 202         dnd_draw(dnd);
 203 }
 204
 205 static void
 206 keyboard_focus_handler(struct window *window,
 207                        struct input *device, void *data)
 208 {
 209         struct dnd *dnd = data;
 210
 211         window_schedule_redraw(dnd->window);
 212 }
 213
 214 static int
 215 dnd_add_item(struct dnd *dnd, struct item *item)
 216 {
 217         int i;
 218
 219         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 220                 if (dnd->items[i] == 0) {
 221                         dnd->items[i] = item;
 222                         return i;
 223                 }
 224         }
 225         return -1;
 226 }
 227
 228 static struct item *
 229 dnd_get_item(struct dnd *dnd, int32_t x, int32_t y)
 230 {
 231         struct item *item;
 232         struct rectangle allocation;
 233         int i;
 234
 235         window_get_child_allocation(dnd->window, &allocation);
 236
 237         x -= allocation.x;
 238         y -= allocation.y;
 239
 240         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 241                 item = dnd->items[i];
 242                 if (item &&
 243                     item->x <= x && x < item->x + item_width &&
 244                     item->y <= y && y < item->y + item_height)
 245                         return item;
 246         }
 247
 248         return NULL;
 249 }
 250
 251 static void
 252 data_source_target(void *data,
 253                    struct wl_data_source *source, const char *mime_type)
 254 {
 255         struct dnd_drag *dnd_drag = data;
 256         struct dnd *dnd = dnd_drag->dnd;
 257         cairo_surface_t *surface;
 258         struct wl_buffer *buffer;
 259         struct wl_data_device *device;
 260
 261         device = input_get_data_device(dnd_drag->input);
 262         dnd_drag->mime_type = mime_type;
 263         if (mime_type)
 264                 surface = dnd_drag->opaque;
 265         else
 266                 surface = dnd_drag->translucent;
 267
 268         buffer = display_get_buffer_for_surface(dnd->display, surface);
 269         wl_data_device_attach(device, dnd_drag->time, buffer,
 270                                   dnd_drag->hotspot_x, dnd_drag->hotspot_y);
 271 }
 272
 273 static void
 274 data_source_send(void *data, struct wl_data_source *source,
 275                  const char *mime_type, int32_t fd)
 276 {
 277         struct dnd_flower_message dnd_flower_message;
 278         struct dnd_drag *dnd_drag = data;
 279
 280         dnd_flower_message.seed = dnd_drag->item->seed;
 281         dnd_flower_message.x_offset = dnd_drag->x_offset;
 282         dnd_flower_message.y_offset = dnd_drag->y_offset;
 283
 284         write(fd, &dnd_flower_message, sizeof dnd_flower_message);
 285         close(fd);
 286 }
 287
 288 static void
 289 data_source_cancelled(void *data, struct wl_data_source *source)
 290 {
 291         struct dnd_drag *dnd_drag = data;
 292
 293         /* The 'cancelled' event means that the source is no longer in
 294          * use by the drag (or current selection).  We need to clean
 295          * up the drag object created and the local state. */
 296
 297         wl_data_source_destroy(dnd_drag->data_source);
 298
 299         /* Destroy the item that has been dragged out */
 300         cairo_surface_destroy(dnd_drag->item->surface);
 301         free(dnd_drag->item);
 302
 303         cairo_surface_destroy(dnd_drag->translucent);
 304         cairo_surface_destroy(dnd_drag->opaque);
 305         free(dnd_drag);
 306 }
 307
 308 static const struct wl_data_source_listener data_source_listener = {
 309         data_source_target,
 310         data_source_send,
 311         data_source_cancelled
 312 };
 313
 314 static cairo_surface_t *
 315 create_drag_cursor(struct dnd_drag *dnd_drag,
 316                    struct item *item, int32_t x, int32_t y, double opacity)
 317 {
 318         struct dnd *dnd = dnd_drag->dnd;
 319         cairo_surface_t *surface, *pointer;
 320         int32_t pointer_width, pointer_height, hotspot_x, hotspot_y;
 321         struct rectangle rectangle;
 322         cairo_pattern_t *pattern;
 323         cairo_t *cr;
 324
 325         pointer = display_get_pointer_surface(dnd->display,
 326                                               POINTER_DRAGGING,
 327                                               &pointer_width,
 328                                               &pointer_height,
 329                                               &hotspot_x,
 330                                               &hotspot_y);
 331
 332         rectangle.width = item_width + 2 * pointer_width;
 333         rectangle.height = item_height + 2 * pointer_height;
 334         surface = display_create_surface(dnd->display, NULL, &rectangle, 0);
 335
 336         cr = cairo_create(surface);
 337         cairo_translate(cr, pointer_width, pointer_height);
 338
 339         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 340         cairo_set_source_rgba(cr, 0, 0, 0, 0);
 341         cairo_paint(cr);
 342
 343         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 344         cairo_set_source_surface(cr, item->surface, 0, 0);
 345         pattern = cairo_pattern_create_rgba(0, 0, 0, opacity);
 346         cairo_mask(cr, pattern);
 347         cairo_pattern_destroy(pattern);
 348
 349         cairo_set_source_surface(cr, pointer,
 350                                  x - item->x - hotspot_x,
 351                                  y - item->y - hotspot_y);
 352         cairo_surface_destroy(pointer);
 353         cairo_paint(cr);
 354         /* FIXME: more cairo-gl brokeness */
 355         surface_flush_device(surface);
 356         cairo_destroy(cr);
 357
 358         dnd_drag->hotspot_x = pointer_width + x - item->x;
 359         dnd_drag->hotspot_y = pointer_height + y - item->y;
 360
 361         return surface;
 362 }
 363
 364 static void
 365 dnd_button_handler(struct window *window,
 366                    struct input *input, uint32_t time,
 367                    int button, int state, void *data)
 368 {
 369         struct dnd *dnd = data;
 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 window *window,
 444                    struct input *input, uint32_t time,
 445                    int32_t x, int32_t y,
 446                    int32_t sx, int32_t sy, void *data)
 447 {
 448         return lookup_cursor(data, sx, sy);
 449 }
 450
 451 static void
 452 dnd_data_handler(struct window *window,
 453                  struct input *input, uint32_t time,
 454                  int32_t x, int32_t y, const char **types, void *data)
 455 {
 456         struct dnd *dnd = data;
 457
 458         if (!dnd_get_item(dnd, x, y)) {
 459                 input_accept(input, time, types[0]);
 460         } else {
 461                 input_accept(input, time, NULL);
 462         }
 463 }
 464
 465 static void
 466 dnd_receive_func(void *data, size_t len, int32_t x, int32_t y, void *user_data)
 467 {
 468         struct dnd *dnd = user_data;
 469         struct dnd_flower_message *message = data;
 470         struct item *item;
 471         struct rectangle allocation;
 472
 473         if (len == 0) {
 474                 return;
 475         } else if (len != sizeof *message) {
 476                 fprintf(stderr, "odd message length %ld, expected %ld\n",
 477                         len, sizeof *message);
 478                 return;
 479         }
 480
 481         window_get_child_allocation(dnd->window, &allocation);
 482         item = item_create(dnd->display,
 483                            x - message->x_offset - allocation.x,
 484                            y - message->y_offset - allocation.y,
 485                            message->seed);
 486
 487         dnd_add_item(dnd, item);
 488         window_schedule_redraw(dnd->window);
 489 }
 490
 491 static void
 492 dnd_drop_handler(struct window *window, struct input *input,
 493                  int32_t x, int32_t y, void *data)
 494 {
 495         struct dnd *dnd = data;
 496
 497         if (dnd_get_item(dnd, x, y)) {
 498                 fprintf(stderr, "got 'drop', but no target\n");
 499                 return;
 500         }
 501
 502         input_receive_drag_data(input,
 503                                 "application/x-wayland-dnd-flower",
 504                                 dnd_receive_func, dnd);
 505 }
 506
 507 static struct dnd *
 508 dnd_create(struct display *display)
 509 {
 510         struct dnd *dnd;
 511         int i, x, y;
 512         int32_t width, height;
 513
 514         dnd = malloc(sizeof *dnd);
 515         if (dnd == NULL)
 516                 return dnd;
 517         memset(dnd, 0, sizeof *dnd);
 518
 519         dnd->window = window_create(display, 400, 400);
 520         window_set_title(dnd->window, "Wayland Drag and Drop Demo");
 521
 522         dnd->display = display;
 523         dnd->key = 100;
 524
 525         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 526                 x = (i % 4) * (item_width + item_padding) + item_padding;
 527                 y = (i / 4) * (item_height + item_padding) + item_padding;
 528                 if ((i ^ (i >> 2)) & 1)
 529                         dnd->items[i] = item_create(display, x, y, 0);
 530                 else
 531                         dnd->items[i] = NULL;
 532         }
 533
 534         window_set_user_data(dnd->window, dnd);
 535         window_set_redraw_handler(dnd->window, redraw_handler);
 536         window_set_keyboard_focus_handler(dnd->window,
 537                                           keyboard_focus_handler);
 538         window_set_button_handler(dnd->window, dnd_button_handler);
 539         window_set_motion_handler(dnd->window, dnd_motion_handler);
 540         window_set_data_handler(dnd->window, dnd_data_handler);
 541         window_set_drop_handler(dnd->window, dnd_drop_handler);
 542
 543         dnd->widget = window_add_widget(dnd->window, dnd);
 544         widget_set_enter_handler(dnd->widget, dnd_enter_handler);
 545
 546         width = 4 * (item_width + item_padding) + item_padding;
 547         height = 4 * (item_height + item_padding) + item_padding;
 548         window_set_child_size(dnd->window, width, height);
 549
 550         dnd_draw(dnd);
 551
 552         return dnd;
 553 }
 554
 555 int
 556 main(int argc, char *argv[])
 557 {
 558         struct display *d;
 559
 560         d = display_create(&argc, &argv, NULL);
 561         if (d == NULL) {
 562                 fprintf(stderr, "failed to create display: %m\n");
 563                 return -1;
 564         }
 565
 566         dnd_create(d);
 567
 568         display_run(d);
 569
 570         return 0;
 571 }