modules/video_output/xcb/x11.c

   1 /**
   2  * @file x11.c
   3  * @brief X C Bindings video output module for VLC media player
   4  */
   5 /*****************************************************************************
   6  * Copyright © 2009 Rémi Denis-Courmont
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either version 2.1 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22
  23 #ifdef HAVE_CONFIG_H
  24 # include <config.h>
  25 #endif
  26
  27 #include <stdlib.h>
  28 #include <assert.h>
  29
  30 #include <xcb/xcb.h>
  31 #include <xcb/shm.h>
  32
  33 #include <vlc_common.h>
  34 #include <vlc_plugin.h>
  35 #include <vlc_vout_display.h>
  36 #include <vlc_picture_pool.h>
  37
  38 #include "pictures.h"
  39 #include "events.h"
  40
  41 static int  Open (vlc_object_t *);
  42 static void Close (vlc_object_t *);
  43
  44 /*
  45  * Module descriptor
  46  */
  47 vlc_module_begin ()
  48     set_shortname (N_("X11"))
  49     set_description (N_("X11 video output (XCB)"))
  50     set_category (CAT_VIDEO)
  51     set_subcategory (SUBCAT_VIDEO_VOUT)
  52     set_capability ("vout display", 100)
  53     set_callbacks (Open, Close)
  54     add_shortcut ("xcb-x11", "x11", "xid")
  55
  56     add_obsolete_bool ("x11-shm") /* obsoleted since 2.0.0 */
  57 vlc_module_end ()
  58
  59 /* This must be large enough to absorb the server display jitter.
  60  * But excessively large value is useless as direct rendering cannot be used
  61  * with XCB X11. */
  62 #define MAX_PICTURES (3)
  63
  64 struct vout_display_sys_t
  65 {
  66     xcb_connection_t *conn;
  67     vout_window_t *embed; /* VLC window */
  68
  69     xcb_cursor_t cursor; /* blank cursor */
  70     xcb_window_t window; /* drawable X window */
  71     xcb_gcontext_t gc; /* context to put images */
  72     xcb_shm_seg_t seg_base; /**< shared memory segment XID base */
  73     bool visible; /* whether to draw */
  74     uint8_t depth; /* useful bits per pixel */
  75
  76     picture_pool_t *pool; /* picture pool */
  77 };
  78
  79 static picture_pool_t *Pool (vout_display_t *, unsigned);
  80 static void Display (vout_display_t *, picture_t *, subpicture_t *subpicture);
  81 static int Control (vout_display_t *, int, va_list);
  82 static void Manage (vout_display_t *);
  83
  84 static void ResetPictures (vout_display_t *);
  85
  86 static const xcb_depth_t *FindDepth (const xcb_screen_t *scr,
  87                                      uint_fast8_t depth)
  88 {
  89     xcb_depth_t *d = NULL;
  90     for (xcb_depth_iterator_t it = xcb_screen_allowed_depths_iterator (scr);
  91          it.rem > 0 && d == NULL;
  92          xcb_depth_next (&it))
  93     {
  94         if (it.data->depth == depth)
  95             d = it.data;
  96     }
  97
  98     return d;
  99 }
 100
 101
 102 /**
 103  * Probe the X server.
 104  */
 105 static int Open (vlc_object_t *obj)
 106 {
 107     vout_display_t *vd = (vout_display_t *)obj;
 108     vout_display_sys_t *sys = malloc (sizeof (*sys));
 109     if (unlikely(sys == NULL))
 110         return VLC_ENOMEM;
 111
 112     vd->sys = sys;
 113     sys->pool = NULL;
 114
 115     /* Get window, connect to X server */
 116     xcb_connection_t *conn;
 117     const xcb_screen_t *scr;
 118     uint16_t width, height;
 119     sys->embed = XCB_parent_Create (vd, &conn, &scr, &width, &height);
 120     if (sys->embed == NULL)
 121     {
 122         free (sys);
 123         return VLC_EGENERIC;
 124     }
 125     sys->conn = conn;
 126
 127     const xcb_setup_t *setup = xcb_get_setup (conn);
 128
 129     /* Determine our pixel format */
 130     video_format_t fmt_pic;
 131     xcb_visualid_t vid = 0;
 132     sys->depth = 0;
 133
 134     for (const xcb_format_t *fmt = xcb_setup_pixmap_formats (setup),
 135              *end = fmt + xcb_setup_pixmap_formats_length (setup);
 136          fmt < end;
 137          fmt++)
 138     {
 139         if (fmt->depth <= sys->depth)
 140             continue; /* no better than earlier format */
 141
 142         video_format_ApplyRotation(&fmt_pic, &vd->fmt);
 143
 144         /* Check that the pixmap format is supported by VLC. */
 145         switch (fmt->depth)
 146         {
 147           case 32:
 148             if (fmt->bits_per_pixel != 32)
 149                 continue;
 150             fmt_pic.i_chroma = VLC_CODEC_ARGB;
 151             break;
 152           case 24:
 153             if (fmt->bits_per_pixel == 32)
 154                 fmt_pic.i_chroma = VLC_CODEC_RGB32;
 155             else if (fmt->bits_per_pixel == 24)
 156                 fmt_pic.i_chroma = VLC_CODEC_RGB24;
 157             else
 158                 continue;
 159             break;
 160           case 16:
 161             if (fmt->bits_per_pixel != 16)
 162                 continue;
 163             fmt_pic.i_chroma = VLC_CODEC_RGB16;
 164             break;
 165           case 15:
 166             if (fmt->bits_per_pixel != 16)
 167                 continue;
 168             fmt_pic.i_chroma = VLC_CODEC_RGB15;
 169             break;
 170           case 8:
 171             if (fmt->bits_per_pixel != 8)
 172                 continue;
 173             fmt_pic.i_chroma = VLC_CODEC_RGB8;
 174             break;
 175           default:
 176             continue;
 177         }
 178
 179         /* Byte sex is a non-issue for 8-bits. It can be worked around with
 180          * RGB masks for 24-bits. Too bad for 15-bits and 16-bits. */
 181         if (fmt->bits_per_pixel == 16 && setup->image_byte_order != ORDER)
 182             continue;
 183
 184         /* Make sure the X server is sane */
 185         assert (fmt->bits_per_pixel > 0);
 186         if (unlikely(fmt->scanline_pad % fmt->bits_per_pixel))
 187             continue;
 188
 189         /* Check that the selected screen supports this depth */
 190         const xcb_depth_t *d = FindDepth (scr, fmt->depth);
 191         if (d == NULL)
 192             continue;
 193
 194         /* Find a visual type for the selected depth */
 195         const xcb_visualtype_t *vt = xcb_depth_visuals (d);
 196
 197         /* First try True Color class */
 198         for (int i = xcb_depth_visuals_length (d); i > 0; i--)
 199         {
 200             if (vt->_class == XCB_VISUAL_CLASS_TRUE_COLOR)
 201             {
 202                 fmt_pic.i_rmask = vt->red_mask;
 203                 fmt_pic.i_gmask = vt->green_mask;
 204                 fmt_pic.i_bmask = vt->blue_mask;
 205             found_visual:
 206                 vid = vt->visual_id;
 207                 msg_Dbg (vd, "using X11 visual ID 0x%"PRIx32, vid);
 208                 sys->depth = fmt->depth;
 209                 msg_Dbg (vd, " %"PRIu8" bits depth", sys->depth);
 210                 msg_Dbg (vd, " %"PRIu8" bits per pixel", fmt->bits_per_pixel);
 211                 msg_Dbg (vd, " %"PRIu8" bits line pad", fmt->scanline_pad);
 212                 goto found_format;
 213             }
 214             vt++;
 215         }
 216
 217         /* Then try Static Gray class */
 218         if (fmt->depth != 8)
 219             continue;
 220         vt = xcb_depth_visuals (d);
 221         for (int i = xcb_depth_visuals_length (d); i > 0 && !vid; i--)
 222         {
 223             if (vt->_class == XCB_VISUAL_CLASS_STATIC_GRAY)
 224             {
 225                 fmt_pic.i_chroma = VLC_CODEC_GREY;
 226                 goto found_visual;
 227             }
 228             vt++;
 229         }
 230     }
 231
 232     msg_Err (obj, "no supported pixel format & visual");
 233     goto error;
 234
 235 found_format:;
 236     /* Create colormap (needed to select non-default visual) */
 237     xcb_colormap_t cmap;
 238     if (vid != scr->root_visual)
 239     {
 240         cmap = xcb_generate_id (conn);
 241         xcb_create_colormap (conn, XCB_COLORMAP_ALLOC_NONE,
 242                              cmap, scr->root, vid);
 243     }
 244     else
 245         cmap = scr->default_colormap;
 246
 247     /* Create window */
 248     sys->window = xcb_generate_id (conn);
 249     sys->gc = xcb_generate_id (conn);
 250     xcb_pixmap_t pixmap = xcb_generate_id (conn);
 251     {
 252         const uint32_t mask =
 253             XCB_CW_BACK_PIXMAP |
 254             XCB_CW_BACK_PIXEL |
 255             XCB_CW_BORDER_PIXMAP |
 256             XCB_CW_BORDER_PIXEL |
 257             XCB_CW_EVENT_MASK |
 258             XCB_CW_COLORMAP;
 259         const uint32_t values[] = {
 260             /* XCB_CW_BACK_PIXMAP */
 261             pixmap,
 262             /* XCB_CW_BACK_PIXEL */
 263             scr->black_pixel,
 264             /* XCB_CW_BORDER_PIXMAP */
 265             pixmap,
 266             /* XCB_CW_BORDER_PIXEL */
 267             scr->black_pixel,
 268             /* XCB_CW_EVENT_MASK */
 269             XCB_EVENT_MASK_VISIBILITY_CHANGE,
 270             /* XCB_CW_COLORMAP */
 271             cmap,
 272         };
 273         xcb_void_cookie_t c;
 274
 275         xcb_create_pixmap (conn, sys->depth, pixmap, scr->root, 1, 1);
 276         c = xcb_create_window_checked (conn, sys->depth, sys->window,
 277                                        sys->embed->handle.xid, 0, 0,
 278                                        width, height, 0,
 279                                        XCB_WINDOW_CLASS_INPUT_OUTPUT,
 280                                        vid, mask, values);
 281         xcb_map_window (conn, sys->window);
 282         /* Create graphic context (I wonder why the heck do we need this) */
 283         xcb_create_gc (conn, sys->gc, sys->window, 0, NULL);
 284
 285         if (XCB_error_Check (vd, conn, "cannot create X11 window", c))
 286             goto error;
 287     }
 288     msg_Dbg (vd, "using X11 window %08"PRIx32, sys->window);
 289     msg_Dbg (vd, "using X11 graphic context %08"PRIx32, sys->gc);
 290
 291     sys->cursor = XCB_cursor_Create (conn, scr);
 292     sys->visible = false;
 293     if (XCB_shm_Check (obj, conn))
 294     {
 295         sys->seg_base = xcb_generate_id (conn);
 296         for (unsigned i = 1; i < MAX_PICTURES; i++)
 297              xcb_generate_id (conn);
 298     }
 299     else
 300         sys->seg_base = 0;
 301
 302     /* Setup vout_display_t once everything is fine */
 303     vd->info.has_pictures_invalid = true;
 304     vd->info.has_event_thread = true;
 305
 306     vd->fmt = fmt_pic;
 307     vd->pool = Pool;
 308     vd->prepare = NULL;
 309     vd->display = Display;
 310     vd->control = Control;
 311     vd->manage = Manage;
 312
 313     /* */
 314     bool is_fullscreen = vd->cfg->is_fullscreen;
 315     if (is_fullscreen && vout_window_SetFullScreen (sys->embed, true))
 316         is_fullscreen = false;
 317     vout_display_SendEventFullscreen (vd, is_fullscreen);
 318     vout_display_SendEventDisplaySize (vd, width, height, is_fullscreen);
 319
 320     return VLC_SUCCESS;
 321
 322 error:
 323     Close (obj);
 324     return VLC_EGENERIC;
 325 }
 326
 327
 328 /**
 329  * Disconnect from the X server.
 330  */
 331 static void Close (vlc_object_t *obj)
 332 {
 333     vout_display_t *vd = (vout_display_t *)obj;
 334     vout_display_sys_t *sys = vd->sys;
 335
 336     ResetPictures (vd);
 337
 338     /* show the default cursor */
 339     xcb_change_window_attributes (sys->conn, sys->embed->handle.xid, XCB_CW_CURSOR,
 340                                   &(uint32_t) { XCB_CURSOR_NONE });
 341     xcb_flush (sys->conn);
 342
 343     /* colormap, window and context are garbage-collected by X */
 344     xcb_disconnect (sys->conn);
 345     vout_display_DeleteWindow (vd, sys->embed);
 346     free (sys);
 347 }
 348
 349 /**
 350  * Return a direct buffer
 351  */
 352 static picture_pool_t *Pool (vout_display_t *vd, unsigned requested_count)
 353 {
 354     vout_display_sys_t *sys = vd->sys;
 355     (void)requested_count;
 356
 357     if (sys->pool)
 358         return sys->pool;
 359
 360     vout_display_place_t place;
 361
 362     vout_display_PlacePicture (&place, &vd->source, vd->cfg, false);
 363
 364     /* */
 365     const uint32_t values[] = { place.x, place.y, place.width, place.height };
 366     xcb_configure_window (sys->conn, sys->window,
 367                           XCB_CONFIG_WINDOW_X | XCB_CONFIG_WINDOW_Y |
 368                           XCB_CONFIG_WINDOW_WIDTH | XCB_CONFIG_WINDOW_HEIGHT,
 369                           values);
 370
 371     picture_t *pic = picture_NewFromFormat (&vd->fmt);
 372     if (!pic)
 373         return NULL;
 374
 375     assert (pic->i_planes == 1);
 376
 377     picture_resource_t res = {
 378        .p = {
 379            [0] = {
 380                .i_lines = pic->p->i_lines,
 381                .i_pitch = pic->p->i_pitch,
 382            },
 383        },
 384     };
 385     picture_Release (pic);
 386
 387     unsigned count;
 388     picture_t *pic_array[MAX_PICTURES];
 389     const size_t size = res.p->i_pitch * res.p->i_lines;
 390     for (count = 0; count < MAX_PICTURES; count++)
 391     {
 392         xcb_shm_seg_t seg = (sys->seg_base != 0) ? (sys->seg_base + count) : 0;
 393
 394         if (XCB_picture_Alloc (vd, &res, size, sys->conn, seg))
 395             break;
 396         pic_array[count] = XCB_picture_NewFromResource (&vd->fmt, &res);
 397         if (unlikely(pic_array[count] == NULL))
 398         {
 399             if (seg != 0)
 400                 xcb_shm_detach (sys->conn, seg);
 401             break;
 402         }
 403     }
 404     xcb_flush (sys->conn);
 405
 406     if (count == 0)
 407         return NULL;
 408
 409     sys->pool = picture_pool_New (count, pic_array);
 410     if (unlikely(sys->pool == NULL))
 411         while (count > 0)
 412             picture_Release(pic_array[--count]);
 413     return sys->pool;
 414 }
 415
 416 /**
 417  * Sends an image to the X server.
 418  */
 419 static void Display (vout_display_t *vd, picture_t *pic, subpicture_t *subpicture)
 420 {
 421     vout_display_sys_t *sys = vd->sys;
 422     xcb_shm_seg_t segment = XCB_picture_GetSegment(pic);
 423     xcb_void_cookie_t ck;
 424
 425     if (!sys->visible)
 426         goto out;
 427     if (segment != 0)
 428         ck = xcb_shm_put_image_checked (sys->conn, sys->window, sys->gc,
 429           /* real width */ pic->p->i_pitch / pic->p->i_pixel_pitch,
 430          /* real height */ pic->p->i_lines,
 431                    /* x */ vd->fmt.i_x_offset,
 432                    /* y */ vd->fmt.i_y_offset,
 433                /* width */ vd->fmt.i_visible_width,
 434               /* height */ vd->fmt.i_visible_height,
 435                            0, 0, sys->depth, XCB_IMAGE_FORMAT_Z_PIXMAP,
 436                            0, segment, 0);
 437     else
 438     {
 439         const size_t offset = vd->fmt.i_y_offset * pic->p->i_pitch;
 440         const unsigned lines = pic->p->i_lines - vd->fmt.i_y_offset;
 441
 442         ck = xcb_put_image_checked (sys->conn, XCB_IMAGE_FORMAT_Z_PIXMAP,
 443                        sys->window, sys->gc,
 444                        pic->p->i_pitch / pic->p->i_pixel_pitch,
 445                        lines, -vd->fmt.i_x_offset, 0, 0, sys->depth,
 446                        pic->p->i_pitch * lines, pic->p->p_pixels + offset);
 447     }
 448
 449     /* Wait for reply. This makes sure that the X server gets CPU time to
 450      * display the picture. xcb_flush() is *not* sufficient: especially with
 451      * shared memory the PUT requests are so short that many of them can fit in
 452      * X11 socket output buffer before the kernel preempts VLC. */
 453     xcb_generic_error_t *e = xcb_request_check (sys->conn, ck);
 454     if (e != NULL)
 455     {
 456         msg_Dbg (vd, "%s: X11 error %d", "cannot put image", e->error_code);
 457         free (e);
 458     }
 459
 460     /* FIXME might be WAY better to wait in some case (be carefull with
 461      * VOUT_DISPLAY_RESET_PICTURES if done) + does not work with
 462      * vout_display wrapper. */
 463 out:
 464     picture_Release (pic);
 465     (void)subpicture;
 466 }
 467
 468 static int Control (vout_display_t *vd, int query, va_list ap)
 469 {
 470     vout_display_sys_t *sys = vd->sys;
 471
 472     switch (query)
 473     {
 474     case VOUT_DISPLAY_CHANGE_FULLSCREEN:
 475     {
 476         const vout_display_cfg_t *c = va_arg (ap, const vout_display_cfg_t *);
 477         return vout_window_SetFullScreen (sys->embed, c->is_fullscreen);
 478     }
 479
 480     case VOUT_DISPLAY_CHANGE_DISPLAY_SIZE:
 481     {
 482         const vout_display_cfg_t *p_cfg =
 483             (const vout_display_cfg_t*)va_arg (ap, const vout_display_cfg_t *);
 484         const bool is_forced = (bool)va_arg (ap, int);
 485
 486         if (is_forced)
 487         {   /* Changing the dimensions of the parent window takes place
 488              * asynchronously (in the X server). Also it might fail or result
 489              * in different dimensions than requested. Request the size change
 490              * and return a failure since the size is not (yet) changed.
 491              * If the change eventually succeeds, HandleParentStructure()
 492              * will trigger a non-forced display size change later. */
 493             vout_window_SetSize (sys->embed, p_cfg->display.width,
 494                                  p_cfg->display.height);
 495             return VLC_EGENERIC;
 496         }
 497
 498         vout_display_place_t place;
 499         vout_display_PlacePicture (&place, &vd->source, p_cfg, false);
 500
 501         if (place.width  != vd->fmt.i_visible_width ||
 502             place.height != vd->fmt.i_visible_height)
 503         {
 504             vout_display_SendEventPicturesInvalid (vd);
 505             return VLC_SUCCESS;
 506         }
 507
 508         /* Move the picture within the window */
 509         const uint32_t values[] = { place.x, place.y };
 510         xcb_configure_window (sys->conn, sys->window,
 511                               XCB_CONFIG_WINDOW_X | XCB_CONFIG_WINDOW_Y,
 512                               values);
 513         return VLC_SUCCESS;
 514     }
 515     case VOUT_DISPLAY_CHANGE_WINDOW_STATE:
 516     {
 517         unsigned state = va_arg (ap, unsigned);
 518         return vout_window_SetState (sys->embed, state);
 519     }
 520
 521     case VOUT_DISPLAY_CHANGE_ZOOM:
 522     case VOUT_DISPLAY_CHANGE_DISPLAY_FILLED:
 523     case VOUT_DISPLAY_CHANGE_SOURCE_ASPECT:
 524     case VOUT_DISPLAY_CHANGE_SOURCE_CROP:
 525         /* I am not sure it is always necessary, but it is way simpler ... */
 526         vout_display_SendEventPicturesInvalid (vd);
 527         return VLC_SUCCESS;
 528
 529     case VOUT_DISPLAY_RESET_PICTURES:
 530     {
 531         ResetPictures (vd);
 532
 533         vout_display_place_t place;
 534         vout_display_PlacePicture (&place, &vd->source, vd->cfg, false);
 535
 536         video_format_t src;
 537         video_format_ApplyRotation(&src, &vd->source);
 538
 539         vd->fmt.i_width  = src.i_width  * place.width / src.i_visible_width;
 540         vd->fmt.i_height = src.i_height * place.height / src.i_visible_height;
 541
 542         vd->fmt.i_visible_width  = place.width;
 543         vd->fmt.i_visible_height = place.height;
 544         vd->fmt.i_x_offset = src.i_x_offset * place.width / src.i_visible_width;
 545         vd->fmt.i_y_offset = src.i_y_offset * place.height / src.i_visible_height;
 546         return VLC_SUCCESS;
 547     }
 548
 549     /* Hide the mouse. It will be send when
 550      * vout_display_t::info.b_hide_mouse is false */
 551     case VOUT_DISPLAY_HIDE_MOUSE:
 552         xcb_change_window_attributes (sys->conn, sys->embed->handle.xid,
 553                                   XCB_CW_CURSOR, &(uint32_t){ sys->cursor });
 554         xcb_flush (sys->conn);
 555         return VLC_SUCCESS;
 556
 557     default:
 558         msg_Err (vd, "Unknown request in XCB vout display");
 559         return VLC_EGENERIC;
 560     }
 561 }
 562
 563 static void Manage (vout_display_t *vd)
 564 {
 565     vout_display_sys_t *sys = vd->sys;
 566
 567     XCB_Manage (vd, sys->conn, &sys->visible);
 568 }
 569
 570 static void ResetPictures (vout_display_t *vd)
 571 {
 572     vout_display_sys_t *sys = vd->sys;
 573
 574     if (!sys->pool)
 575         return;
 576
 577     if (sys->seg_base != 0)
 578         for (unsigned i = 0; i < MAX_PICTURES; i++)
 579             xcb_shm_detach (sys->conn, sys->seg_base + i);
 580
 581     picture_pool_Delete (sys->pool);
 582     sys->pool = NULL;
 583 }