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_redraw_handler(struct widget *widget, void *data)
 164 {
 165         struct dnd *dnd = data;
 166         struct rectangle allocation;
 167         cairo_t *cr;
 168         cairo_surface_t *surface;
 169         int i;
 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 }
 194
 195 static void
 196 keyboard_focus_handler(struct window *window,
 197                        struct input *device, void *data)
 198 {
 199         struct dnd *dnd = data;
 200
 201         window_schedule_redraw(dnd->window);
 202 }
 203
 204 static int
 205 dnd_add_item(struct dnd *dnd, struct item *item)
 206 {
 207         int i;
 208
 209         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 210                 if (dnd->items[i] == 0) {
 211                         dnd->items[i] = item;
 212                         return i;
 213                 }
 214         }
 215         return -1;
 216 }
 217
 218 static struct item *
 219 dnd_get_item(struct dnd *dnd, int32_t x, int32_t y)
 220 {
 221         struct item *item;
 222         struct rectangle allocation;
 223         int i;
 224
 225         window_get_child_allocation(dnd->window, &allocation);
 226
 227         x -= allocation.x;
 228         y -= allocation.y;
 229
 230         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 231                 item = dnd->items[i];
 232                 if (item &&
 233                     item->x <= x && x < item->x + item_width &&
 234                     item->y <= y && y < item->y + item_height)
 235                         return item;
 236         }
 237
 238         return NULL;
 239 }
 240
 241 static void
 242 data_source_target(void *data,
 243                    struct wl_data_source *source, const char *mime_type)
 244 {
 245         struct dnd_drag *dnd_drag = data;
 246         struct dnd *dnd = dnd_drag->dnd;
 247         cairo_surface_t *surface;
 248         struct wl_buffer *buffer;
 249         struct wl_data_device *device;
 250
 251         device = input_get_data_device(dnd_drag->input);
 252         dnd_drag->mime_type = mime_type;
 253         if (mime_type)
 254                 surface = dnd_drag->opaque;
 255         else
 256                 surface = dnd_drag->translucent;
 257
 258         buffer = display_get_buffer_for_surface(dnd->display, surface);
 259         wl_data_device_attach(device, dnd_drag->time, buffer,
 260                                   dnd_drag->hotspot_x, dnd_drag->hotspot_y);
 261 }
 262
 263 static void
 264 data_source_send(void *data, struct wl_data_source *source,
 265                  const char *mime_type, int32_t fd)
 266 {
 267         struct dnd_flower_message dnd_flower_message;
 268         struct dnd_drag *dnd_drag = data;
 269
 270         dnd_flower_message.seed = dnd_drag->item->seed;
 271         dnd_flower_message.x_offset = dnd_drag->x_offset;
 272         dnd_flower_message.y_offset = dnd_drag->y_offset;
 273
 274         write(fd, &dnd_flower_message, sizeof dnd_flower_message);
 275         close(fd);
 276 }
 277
 278 static void
 279 data_source_cancelled(void *data, struct wl_data_source *source)
 280 {
 281         struct dnd_drag *dnd_drag = data;
 282
 283         /* The 'cancelled' event means that the source is no longer in
 284          * use by the drag (or current selection).  We need to clean
 285          * up the drag object created and the local state. */
 286
 287         wl_data_source_destroy(dnd_drag->data_source);
 288
 289         /* Destroy the item that has been dragged out */
 290         cairo_surface_destroy(dnd_drag->item->surface);
 291         free(dnd_drag->item);
 292
 293         cairo_surface_destroy(dnd_drag->translucent);
 294         cairo_surface_destroy(dnd_drag->opaque);
 295         free(dnd_drag);
 296 }
 297
 298 static const struct wl_data_source_listener data_source_listener = {
 299         data_source_target,
 300         data_source_send,
 301         data_source_cancelled
 302 };
 303
 304 static cairo_surface_t *
 305 create_drag_cursor(struct dnd_drag *dnd_drag,
 306                    struct item *item, int32_t x, int32_t y, double opacity)
 307 {
 308         struct dnd *dnd = dnd_drag->dnd;
 309         cairo_surface_t *surface, *pointer;
 310         int32_t pointer_width, pointer_height, hotspot_x, hotspot_y;
 311         struct rectangle rectangle;
 312         cairo_pattern_t *pattern;
 313         cairo_t *cr;
 314
 315         pointer = display_get_pointer_surface(dnd->display,
 316                                               POINTER_DRAGGING,
 317                                               &pointer_width,
 318                                               &pointer_height,
 319                                               &hotspot_x,
 320                                               &hotspot_y);
 321
 322         rectangle.width = item_width + 2 * pointer_width;
 323         rectangle.height = item_height + 2 * pointer_height;
 324         surface = display_create_surface(dnd->display, NULL, &rectangle, 0);
 325
 326         cr = cairo_create(surface);
 327         cairo_translate(cr, pointer_width, pointer_height);
 328
 329         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 330         cairo_set_source_rgba(cr, 0, 0, 0, 0);
 331         cairo_paint(cr);
 332
 333         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 334         cairo_set_source_surface(cr, item->surface, 0, 0);
 335         pattern = cairo_pattern_create_rgba(0, 0, 0, opacity);
 336         cairo_mask(cr, pattern);
 337         cairo_pattern_destroy(pattern);
 338
 339         cairo_set_source_surface(cr, pointer,
 340                                  x - item->x - hotspot_x,
 341                                  y - item->y - hotspot_y);
 342         cairo_surface_destroy(pointer);
 343         cairo_paint(cr);
 344         /* FIXME: more cairo-gl brokeness */
 345         surface_flush_device(surface);
 346         cairo_destroy(cr);
 347
 348         dnd_drag->hotspot_x = pointer_width + x - item->x;
 349         dnd_drag->hotspot_y = pointer_height + y - item->y;
 350
 351         return surface;
 352 }
 353
 354 static void
 355 dnd_button_handler(struct widget *widget,
 356                    struct input *input, uint32_t time,
 357                    int button, int state, void *data)
 358 {
 359         struct dnd *dnd = data;
 360         int32_t x, y;
 361         struct item *item;
 362         struct rectangle allocation;
 363         struct dnd_drag *dnd_drag;
 364         int i;
 365
 366         window_get_child_allocation(dnd->window, &allocation);
 367         input_get_position(input, &x, &y);
 368         item = dnd_get_item(dnd, x, y);
 369         x -= allocation.x;
 370         y -= allocation.y;
 371
 372         if (item && state == 1) {
 373                 dnd_drag = malloc(sizeof *dnd_drag);
 374                 dnd_drag->dnd = dnd;
 375                 dnd_drag->input = input;
 376                 dnd_drag->time = time;
 377                 dnd_drag->item = item;
 378                 dnd_drag->x_offset = x - item->x;
 379                 dnd_drag->y_offset = y - item->y;
 380
 381                 for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 382                         if (item == dnd->items[i]){
 383                                 dnd->items[i] = 0;
 384                                 break;
 385                         }
 386                 }
 387
 388                 dnd_drag->data_source =
 389                         display_create_data_source(dnd->display);
 390                 wl_data_source_add_listener(dnd_drag->data_source,
 391                                             &data_source_listener,
 392                                             dnd_drag);
 393                 wl_data_source_offer(dnd_drag->data_source,
 394                                      "application/x-wayland-dnd-flower");
 395                 wl_data_source_offer(dnd_drag->data_source,
 396                                      "text/plain; charset=utf-8");
 397                 wl_data_device_start_drag(input_get_data_device(input),
 398                                           dnd_drag->data_source,
 399                                           window_get_wl_surface(dnd->window),
 400                                           time);
 401
 402                 input_set_pointer_image(input, time, POINTER_DRAGGING);
 403
 404                 dnd_drag->opaque =
 405                         create_drag_cursor(dnd_drag, item, x, y, 1);
 406                 dnd_drag->translucent =
 407                         create_drag_cursor(dnd_drag, item, x, y, 0.2);
 408
 409                 window_schedule_redraw(dnd->window);
 410         }
 411 }
 412
 413 static int
 414 lookup_cursor(struct dnd *dnd, int x, int y)
 415 {
 416         struct item *item;
 417
 418         item = dnd_get_item(dnd, x, y);
 419         if (item)
 420                 return POINTER_HAND1;
 421         else
 422                 return POINTER_LEFT_PTR;
 423 }
 424
 425 static int
 426 dnd_enter_handler(struct widget *widget,
 427                   struct input *input, uint32_t time,
 428                   int32_t x, int32_t y, void *data)
 429 {
 430         return lookup_cursor(data, x, y);
 431 }
 432
 433 static int
 434 dnd_motion_handler(struct widget *widget,
 435                    struct input *input, uint32_t time,
 436                    int32_t x, int32_t y, void *data)
 437 {
 438         return lookup_cursor(data, x, y);
 439 }
 440
 441 static void
 442 dnd_data_handler(struct window *window,
 443                  struct input *input, uint32_t time,
 444                  int32_t x, int32_t y, const char **types, void *data)
 445 {
 446         struct dnd *dnd = data;
 447
 448         if (!dnd_get_item(dnd, x, y)) {
 449                 input_accept(input, time, types[0]);
 450         } else {
 451                 input_accept(input, time, NULL);
 452         }
 453 }
 454
 455 static void
 456 dnd_receive_func(void *data, size_t len, int32_t x, int32_t y, void *user_data)
 457 {
 458         struct dnd *dnd = user_data;
 459         struct dnd_flower_message *message = data;
 460         struct item *item;
 461         struct rectangle allocation;
 462
 463         if (len == 0) {
 464                 return;
 465         } else if (len != sizeof *message) {
 466                 fprintf(stderr, "odd message length %ld, expected %ld\n",
 467                         len, sizeof *message);
 468                 return;
 469         }
 470
 471         window_get_child_allocation(dnd->window, &allocation);
 472         item = item_create(dnd->display,
 473                            x - message->x_offset - allocation.x,
 474                            y - message->y_offset - allocation.y,
 475                            message->seed);
 476
 477         dnd_add_item(dnd, item);
 478         window_schedule_redraw(dnd->window);
 479 }
 480
 481 static void
 482 dnd_drop_handler(struct window *window, struct input *input,
 483                  int32_t x, int32_t y, void *data)
 484 {
 485         struct dnd *dnd = data;
 486
 487         if (dnd_get_item(dnd, x, y)) {
 488                 fprintf(stderr, "got 'drop', but no target\n");
 489                 return;
 490         }
 491
 492         input_receive_drag_data(input,
 493                                 "application/x-wayland-dnd-flower",
 494                                 dnd_receive_func, dnd);
 495 }
 496
 497 static struct dnd *
 498 dnd_create(struct display *display)
 499 {
 500         struct dnd *dnd;
 501         int i, x, y;
 502         int32_t width, height;
 503
 504         dnd = malloc(sizeof *dnd);
 505         if (dnd == NULL)
 506                 return dnd;
 507         memset(dnd, 0, sizeof *dnd);
 508
 509         dnd->window = window_create(display, 400, 400);
 510         dnd->widget = window_add_widget(dnd->window, dnd);
 511         window_set_title(dnd->window, "Wayland Drag and Drop Demo");
 512
 513         dnd->display = display;
 514         dnd->key = 100;
 515
 516         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 517                 x = (i % 4) * (item_width + item_padding) + item_padding;
 518                 y = (i / 4) * (item_height + item_padding) + item_padding;
 519                 if ((i ^ (i >> 2)) & 1)
 520                         dnd->items[i] = item_create(display, x, y, 0);
 521                 else
 522                         dnd->items[i] = NULL;
 523         }
 524
 525         window_set_user_data(dnd->window, dnd);
 526         window_set_keyboard_focus_handler(dnd->window,
 527                                           keyboard_focus_handler);
 528         window_set_data_handler(dnd->window, dnd_data_handler);
 529         window_set_drop_handler(dnd->window, dnd_drop_handler);
 530
 531         widget_set_redraw_handler(dnd->widget, dnd_redraw_handler);
 532         widget_set_enter_handler(dnd->widget, dnd_enter_handler);
 533         widget_set_motion_handler(dnd->widget, dnd_motion_handler);
 534         widget_set_button_handler(dnd->widget, dnd_button_handler);
 535
 536         width = 4 * (item_width + item_padding) + item_padding;
 537         height = 4 * (item_height + item_padding) + item_padding;
 538         window_set_child_size(dnd->window, width, height);
 539
 540         window_schedule_redraw(dnd->window);
 541
 542         return dnd;
 543 }
 544
 545 int
 546 main(int argc, char *argv[])
 547 {
 548         struct display *d;
 549
 550         d = display_create(&argc, &argv, NULL);
 551         if (d == NULL) {
 552                 fprintf(stderr, "failed to create display: %m\n");
 553                 return -1;
 554         }
 555
 556         dnd_create(d);
 557
 558         display_run(d);
 559
 560         return 0;
 561 }