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_surface *drag_surface;
  59         struct wl_data_source *data_source;
  60 };
  61
  62 struct item {
  63         cairo_surface_t *surface;
  64         int seed;
  65         int x, y;
  66 };
  67
  68 struct dnd_flower_message {
  69         int seed, x_offset, y_offset;
  70 };
  71
  72
  73 static const int item_width = 64;
  74 static const int item_height = 64;
  75 static const int item_padding = 16;
  76
  77 static struct item *
  78 item_create(struct display *display, int x, int y, int seed)
  79 {
  80         struct item *item;
  81         struct timeval tv;
  82
  83         item = malloc(sizeof *item);
  84         if (item == NULL)
  85                 return NULL;
  86
  87
  88         gettimeofday(&tv, NULL);
  89         item->seed = seed ? seed : tv.tv_usec;
  90         srandom(item->seed);
  91
  92         const int petal_count = 3 + random() % 5;
  93         const double r1 = 20 + random() % 10;
  94         const double r2 = 5 + random() % 12;
  95         const double u = (10 + random() % 90) / 100.0;
  96         const double v = (random() % 90) / 100.0;
  97
  98         cairo_t *cr;
  99         int i;
 100         double t, dt = 2 * M_PI / (petal_count * 2);
 101         double x1, y1, x2, y2, x3, y3;
 102         struct rectangle rect;
 103
 104
 105         rect.width = item_width;
 106         rect.height = item_height;
 107         item->surface = display_create_surface(display, NULL, &rect, 0);
 108
 109         item->x = x;
 110         item->y = y;
 111
 112         cr = cairo_create(item->surface);
 113         cairo_set_operator(cr, CAIRO_OPERATOR_SOURCE);
 114         cairo_set_source_rgba(cr, 0, 0, 0, 0);
 115         cairo_paint(cr);
 116
 117         cairo_set_operator(cr, CAIRO_OPERATOR_OVER);
 118         cairo_translate(cr, item_width / 2, item_height / 2);
 119         t = random();
 120         cairo_move_to(cr, cos(t) * r1, sin(t) * r1);
 121         for (i = 0; i < petal_count; i++, t += dt * 2) {
 122                 x1 = cos(t) * r1;
 123                 y1 = sin(t) * r1;
 124                 x2 = cos(t + dt) * r2;
 125                 y2 = sin(t + dt) * r2;
 126                 x3 = cos(t + 2 * dt) * r1;
 127                 y3 = sin(t + 2 * dt) * r1;
 128
 129                 cairo_curve_to(cr,
 130                                x1 - y1 * u, y1 + x1 * u,
 131                                x2 + y2 * v, y2 - x2 * v,
 132                                x2, y2);
 133
 134                 cairo_curve_to(cr,
 135                                x2 - y2 * v, y2 + x2 * v,
 136                                x3 + y3 * u, y3 - x3 * u,
 137                                x3, y3);
 138         }
 139
 140         cairo_close_path(cr);
 141
 142         cairo_set_source_rgba(cr,
 143                               0.5 + (random() % 50) / 49.0,
 144                               0.5 + (random() % 50) / 49.0,
 145                               0.5 + (random() % 50) / 49.0,
 146                               0.5 + (random() % 100) / 99.0);
 147
 148         cairo_fill_preserve(cr);
 149
 150         cairo_set_line_width(cr, 1);
 151         cairo_set_source_rgba(cr,
 152                               0.5 + (random() % 50) / 49.0,
 153                               0.5 + (random() % 50) / 49.0,
 154                               0.5 + (random() % 50) / 49.0,
 155                               0.5 + (random() % 100) / 99.0);
 156         cairo_stroke(cr);
 157
 158         cairo_destroy(cr);
 159
 160         return item;
 161 }
 162
 163 static void
 164 dnd_redraw_handler(struct widget *widget, void *data)
 165 {
 166         struct dnd *dnd = data;
 167         struct rectangle allocation;
 168         cairo_t *cr;
 169         cairo_surface_t *surface;
 170         int i;
 171
 172         surface = window_get_surface(dnd->window);
 173         cr = cairo_create(surface);
 174         widget_get_allocation(dnd->widget, &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 }
 195
 196 static void
 197 keyboard_focus_handler(struct window *window,
 198                        struct input *device, void *data)
 199 {
 200         struct dnd *dnd = data;
 201
 202         window_schedule_redraw(dnd->window);
 203 }
 204
 205 static int
 206 dnd_add_item(struct dnd *dnd, struct item *item)
 207 {
 208         int i;
 209
 210         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 211                 if (dnd->items[i] == 0) {
 212                         dnd->items[i] = item;
 213                         return i;
 214                 }
 215         }
 216         return -1;
 217 }
 218
 219 static struct item *
 220 dnd_get_item(struct dnd *dnd, int32_t x, int32_t y)
 221 {
 222         struct item *item;
 223         struct rectangle allocation;
 224         int i;
 225
 226         widget_get_allocation(dnd->widget, &allocation);
 227
 228         x -= allocation.x;
 229         y -= allocation.y;
 230
 231         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 232                 item = dnd->items[i];
 233                 if (item &&
 234                     item->x <= x && x < item->x + item_width &&
 235                     item->y <= y && y < item->y + item_height)
 236                         return item;
 237         }
 238
 239         return NULL;
 240 }
 241
 242 static void
 243 data_source_target(void *data,
 244                    struct wl_data_source *source, const char *mime_type)
 245 {
 246         struct dnd_drag *dnd_drag = data;
 247         struct dnd *dnd = dnd_drag->dnd;
 248         cairo_surface_t *surface;
 249         struct wl_buffer *buffer;
 250
 251         dnd_drag->mime_type = mime_type;
 252         if (mime_type)
 253                 surface = dnd_drag->opaque;
 254         else
 255                 surface = dnd_drag->translucent;
 256
 257         buffer = display_get_buffer_for_surface(dnd->display, surface);
 258         wl_surface_attach(dnd_drag->drag_surface, buffer, 0, 0);
 259 }
 260
 261 static void
 262 data_source_send(void *data, struct wl_data_source *source,
 263                  const char *mime_type, int32_t fd)
 264 {
 265         struct dnd_flower_message dnd_flower_message;
 266         struct dnd_drag *dnd_drag = data;
 267
 268         dnd_flower_message.seed = dnd_drag->item->seed;
 269         dnd_flower_message.x_offset = dnd_drag->x_offset;
 270         dnd_flower_message.y_offset = dnd_drag->y_offset;
 271
 272         write(fd, &dnd_flower_message, sizeof dnd_flower_message);
 273         close(fd);
 274 }
 275
 276 static void
 277 data_source_cancelled(void *data, struct wl_data_source *source)
 278 {
 279         struct dnd_drag *dnd_drag = data;
 280
 281         /* The 'cancelled' event means that the source is no longer in
 282          * use by the drag (or current selection).  We need to clean
 283          * up the drag object created and the local state. */
 284
 285         wl_data_source_destroy(dnd_drag->data_source);
 286
 287         /* Destroy the item that has been dragged out */
 288         cairo_surface_destroy(dnd_drag->item->surface);
 289         free(dnd_drag->item);
 290
 291         wl_surface_destroy(dnd_drag->drag_surface);
 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         struct display *display;
 365         struct wl_compositor *compositor;
 366         struct wl_buffer *buffer;
 367         int i;
 368
 369         widget_get_allocation(dnd->widget, &allocation);
 370         input_get_position(input, &x, &y);
 371         item = dnd_get_item(dnd, x, y);
 372         x -= allocation.x;
 373         y -= allocation.y;
 374
 375         if (item && state == 1) {
 376                 dnd_drag = malloc(sizeof *dnd_drag);
 377                 dnd_drag->dnd = dnd;
 378                 dnd_drag->input = input;
 379                 dnd_drag->time = time;
 380                 dnd_drag->item = item;
 381                 dnd_drag->x_offset = x - item->x;
 382                 dnd_drag->y_offset = y - item->y;
 383
 384                 for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 385                         if (item == dnd->items[i]){
 386                                 dnd->items[i] = 0;
 387                                 break;
 388                         }
 389                 }
 390
 391                 display = window_get_display(dnd->window);
 392                 compositor = display_get_compositor(display);
 393                 dnd_drag->drag_surface =
 394                         wl_compositor_create_surface(compositor);
 395
 396                 dnd_drag->data_source =
 397                         display_create_data_source(dnd->display);
 398                 wl_data_source_add_listener(dnd_drag->data_source,
 399                                             &data_source_listener,
 400                                             dnd_drag);
 401                 wl_data_source_offer(dnd_drag->data_source,
 402                                      "application/x-wayland-dnd-flower");
 403                 wl_data_source_offer(dnd_drag->data_source,
 404                                      "text/plain; charset=utf-8");
 405                 wl_data_device_start_drag(input_get_data_device(input),
 406                                           dnd_drag->data_source,
 407                                           window_get_wl_surface(dnd->window),
 408                                           dnd_drag->drag_surface,
 409                                           time);
 410
 411                 input_set_pointer_image(input, time, POINTER_DRAGGING);
 412
 413                 dnd_drag->opaque =
 414                         create_drag_cursor(dnd_drag, item, x, y, 1);
 415                 dnd_drag->translucent =
 416                         create_drag_cursor(dnd_drag, item, x, y, 0.2);
 417
 418                 buffer = display_get_buffer_for_surface(dnd->display, dnd_drag->translucent);
 419                 wl_surface_attach(dnd_drag->drag_surface, buffer,
 420                                   -dnd_drag->hotspot_x, -dnd_drag->hotspot_y);
 421
 422                 window_schedule_redraw(dnd->window);
 423         }
 424 }
 425
 426 static int
 427 lookup_cursor(struct dnd *dnd, int x, int y)
 428 {
 429         struct item *item;
 430
 431         item = dnd_get_item(dnd, x, y);
 432         if (item)
 433                 return POINTER_HAND1;
 434         else
 435                 return POINTER_LEFT_PTR;
 436 }
 437
 438 static int
 439 dnd_enter_handler(struct widget *widget,
 440                   struct input *input, uint32_t time,
 441                   int32_t x, int32_t y, void *data)
 442 {
 443         return lookup_cursor(data, x, y);
 444 }
 445
 446 static int
 447 dnd_motion_handler(struct widget *widget,
 448                    struct input *input, uint32_t time,
 449                    int32_t x, int32_t y, void *data)
 450 {
 451         return lookup_cursor(data, x, y);
 452 }
 453
 454 static void
 455 dnd_data_handler(struct window *window,
 456                  struct input *input, uint32_t time,
 457                  int32_t x, int32_t y, const char **types, void *data)
 458 {
 459         struct dnd *dnd = data;
 460
 461         if (!dnd_get_item(dnd, x, y)) {
 462                 input_accept(input, time, types[0]);
 463         } else {
 464                 input_accept(input, time, NULL);
 465         }
 466 }
 467
 468 static void
 469 dnd_receive_func(void *data, size_t len, int32_t x, int32_t y, void *user_data)
 470 {
 471         struct dnd *dnd = user_data;
 472         struct dnd_flower_message *message = data;
 473         struct item *item;
 474         struct rectangle allocation;
 475
 476         if (len == 0) {
 477                 return;
 478         } else if (len != sizeof *message) {
 479                 fprintf(stderr, "odd message length %ld, expected %ld\n",
 480                         len, sizeof *message);
 481                 return;
 482         }
 483
 484         widget_get_allocation(dnd->widget, &allocation);
 485         item = item_create(dnd->display,
 486                            x - message->x_offset - allocation.x,
 487                            y - message->y_offset - allocation.y,
 488                            message->seed);
 489
 490         dnd_add_item(dnd, item);
 491         window_schedule_redraw(dnd->window);
 492 }
 493
 494 static void
 495 dnd_drop_handler(struct window *window, struct input *input,
 496                  int32_t x, int32_t y, void *data)
 497 {
 498         struct dnd *dnd = data;
 499
 500         if (dnd_get_item(dnd, x, y)) {
 501                 fprintf(stderr, "got 'drop', but no target\n");
 502                 return;
 503         }
 504
 505         input_receive_drag_data(input,
 506                                 "application/x-wayland-dnd-flower",
 507                                 dnd_receive_func, dnd);
 508 }
 509
 510 static struct dnd *
 511 dnd_create(struct display *display)
 512 {
 513         struct dnd *dnd;
 514         int i, x, y;
 515         int32_t width, height;
 516
 517         dnd = malloc(sizeof *dnd);
 518         if (dnd == NULL)
 519                 return dnd;
 520         memset(dnd, 0, sizeof *dnd);
 521
 522         dnd->window = window_create(display);
 523         dnd->widget = frame_create(dnd->window, dnd);
 524         window_set_title(dnd->window, "Wayland Drag and Drop Demo");
 525
 526         dnd->display = display;
 527         dnd->key = 100;
 528
 529         for (i = 0; i < ARRAY_LENGTH(dnd->items); i++) {
 530                 x = (i % 4) * (item_width + item_padding) + item_padding;
 531                 y = (i / 4) * (item_height + item_padding) + item_padding;
 532                 if ((i ^ (i >> 2)) & 1)
 533                         dnd->items[i] = item_create(display, x, y, 0);
 534                 else
 535                         dnd->items[i] = NULL;
 536         }
 537
 538         window_set_user_data(dnd->window, dnd);
 539         window_set_keyboard_focus_handler(dnd->window,
 540                                           keyboard_focus_handler);
 541         window_set_data_handler(dnd->window, dnd_data_handler);
 542         window_set_drop_handler(dnd->window, dnd_drop_handler);
 543
 544         widget_set_redraw_handler(dnd->widget, dnd_redraw_handler);
 545         widget_set_enter_handler(dnd->widget, dnd_enter_handler);
 546         widget_set_motion_handler(dnd->widget, dnd_motion_handler);
 547         widget_set_button_handler(dnd->widget, dnd_button_handler);
 548
 549         width = 4 * (item_width + item_padding) + item_padding;
 550         height = 4 * (item_height + item_padding) + item_padding;
 551
 552         widget_schedule_resize(dnd->widget, width, height);
 553
 554         return dnd;
 555 }
 556
 557 int
 558 main(int argc, char *argv[])
 559 {
 560         struct display *d;
 561
 562         d = display_create(argc, argv);
 563         if (d == NULL) {
 564                 fprintf(stderr, "failed to create display: %m\n");
 565                 return -1;
 566         }
 567
 568         dnd_create(d);
 569
 570         display_run(d);
 571
 572         return 0;
 573 }