3 * @brief X C Bindings video output module for VLC media player
5 /*****************************************************************************
6 * Copyright © 2009 Rémi Denis-Courmont
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version 2.0
11 * of the License, or (at your option) any later version.
13 * This library 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 General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
21 ****************************************************************************/
30 #include <sys/types.h>
36 #include <xcb/xcb_image.h>
38 #include <vlc_common.h>
39 #include <vlc_plugin.h>
41 #include <vlc_window.h>
45 #define DISPLAY_TEXT N_("X11 display")
46 #define DISPLAY_LONGTEXT N_( \
47 "X11 hardware display to use. By default VLC will " \
48 "use the value of the DISPLAY environment variable.")
50 #define SHM_TEXT N_("Use shared memory")
51 #define SHM_LONGTEXT N_( \
52 "Use shared memory to communicate between VLC and the X server.")
54 static int Open (vlc_object_t *);
55 static void Close (vlc_object_t *);
61 set_shortname (N_("XCB"))
62 set_description (N_("(Experimental) XCB video output"))
63 set_category (CAT_VIDEO)
64 set_subcategory (SUBCAT_VIDEO_VOUT)
65 set_capability ("video output", 0)
66 set_callbacks (Open, Close)
68 add_string ("x11-display", NULL, NULL,
69 DISPLAY_TEXT, DISPLAY_LONGTEXT, true)
70 add_bool ("x11-shm", true, NULL, SHM_TEXT, SHM_LONGTEXT, true)
75 xcb_connection_t *conn;
76 vout_window_t *embed; /* VLC window (when windowed) */
78 xcb_window_t window; /* drawable X window */
79 xcb_gcontext_t gc; /* context to put images */
80 bool shm; /* whether to use MIT-SHM */
81 uint8_t bpp; /* bits per pixel */
82 uint8_t pad; /* scanline pad */
83 uint8_t depth; /* useful bits per pixel */
84 uint8_t byte_order; /* server byte order */
87 static int Init (vout_thread_t *);
88 static void Deinit (vout_thread_t *);
89 static void Display (vout_thread_t *, picture_t *);
90 static int Manage (vout_thread_t *);
92 int CheckError (vout_thread_t *vout, const char *str, xcb_void_cookie_t ck)
94 xcb_generic_error_t *err;
96 err = xcb_request_check (vout->p_sys->conn, ck);
99 msg_Err (vout, "%s: X11 error %d", str, err->error_code);
108 * Probe the X server.
110 static int Open (vlc_object_t *obj)
112 vout_thread_t *vout = (vout_thread_t *)obj;
113 vout_sys_t *p_sys = malloc (sizeof (*p_sys));
122 char *display = var_CreateGetNonEmptyString (vout, "x11-display");
123 p_sys->conn = xcb_connect (display, NULL);
124 if (xcb_connection_has_error (p_sys->conn) /*== NULL*/)
126 msg_Err (vout, "cannot connect to X server %s",
127 display ? display : "");
134 p_sys->embed = vout_RequestXWindow (vout, &(int){ 0 }, &(int){ 0 },
135 &(unsigned){ 0 }, &(unsigned){ 0 });
136 if (p_sys->embed == NULL)
138 msg_Err (vout, "parent window not available");
143 xcb_get_geometry_reply_t *geo;
144 xcb_get_geometry_cookie_t ck;
146 ck = xcb_get_geometry (p_sys->conn, p_sys->embed->handle.xid);
147 geo = xcb_get_geometry_reply (p_sys->conn, ck, NULL);
150 msg_Err (vout, "parent window not valid");
156 /* Subscribe to parent window resize events */
157 const uint32_t value = XCB_EVENT_MASK_STRUCTURE_NOTIFY;
158 xcb_change_window_attributes (p_sys->conn, p_sys->embed->handle.xid,
159 XCB_CW_EVENT_MASK, &value);
162 /* Find the selected screen */
163 const xcb_setup_t *setup = xcb_get_setup (p_sys->conn);
164 p_sys->byte_order = setup->image_byte_order;
166 xcb_screen_t *scr = NULL;
167 for (xcb_screen_iterator_t i = xcb_setup_roots_iterator (setup);
168 i.rem > 0 && scr == NULL; xcb_screen_next (&i))
170 if (i.data->root == root)
176 msg_Err (vout, "parent window screen not found");
179 msg_Dbg (vout, "using screen 0x%"PRIx32, scr->root);
181 /* Determine our video format. Normally, this is done in pf_init(), but
182 * this plugin always uses the same format for a given X11 screen. */
183 xcb_visualid_t vid = 0;
186 for (const xcb_format_t *fmt = xcb_setup_pixmap_formats (setup),
187 *end = fmt + xcb_setup_pixmap_formats_length (setup);
190 vlc_fourcc_t chroma = 0;
192 if (fmt->depth < depth)
193 continue; /* We already found a better format! */
195 /* Check that the pixmap format is supported by VLC. */
199 if (fmt->bits_per_pixel == 32)
200 chroma = VLC_FOURCC ('R', 'V', '3', '2');
201 else if (fmt->bits_per_pixel == 24)
202 chroma = VLC_FOURCC ('R', 'V', '2', '4');
207 if (fmt->bits_per_pixel != 16)
209 chroma = VLC_FOURCC ('R', 'V', '1', '6');
212 if (fmt->bits_per_pixel != 16)
214 chroma = VLC_FOURCC ('R', 'V', '1', '5');
217 if (fmt->bits_per_pixel != 8)
219 chroma = VLC_FOURCC ('R', 'G', 'B', '2');
224 if ((fmt->bits_per_pixel << 4) % fmt->scanline_pad)
225 continue; /* VLC pads lines to 16 pixels internally */
227 /* Byte sex is a non-issue for 8-bits. It can be worked around with
228 * RGB masks for 24-bits. Too bad for 15-bits and 16-bits. */
229 #ifdef WORDS_BIGENDIAN
230 # define ORDER XCB_IMAGE_ORDER_MSB_FIRST
232 # define ORDER XCB_IMAGE_ORDER_LSB_FIRST
234 if (fmt->bits_per_pixel == 16 && setup->image_byte_order != ORDER)
237 /* Check that the selected screen supports this depth */
238 xcb_depth_iterator_t it = xcb_screen_allowed_depths_iterator (scr);
239 while (it.rem > 0 && it.data->depth != fmt->depth)
240 xcb_depth_next (&it);
242 continue; /* Depth not supported on this screen */
244 /* Find a visual type for the selected depth */
245 const xcb_visualtype_t *vt = xcb_depth_visuals (it.data);
246 for (int i = xcb_depth_visuals_length (it.data); i > 0; i--)
248 if (vt->_class == XCB_VISUAL_CLASS_TRUE_COLOR)
254 if (fmt->depth == 8 && vt->_class == XCB_VISUAL_CLASS_STATIC_GRAY)
257 continue; /* Prefer color over gray scale */
259 chroma = VLC_FOURCC ('G', 'R', 'E', 'Y');
264 continue; /* The screen does not *really* support this depth */
266 vout->fmt_out.i_chroma = vout->output.i_chroma = chroma;
269 vout->output.i_rmask = vt->red_mask;
270 vout->output.i_gmask = vt->green_mask;
271 vout->output.i_bmask = vt->blue_mask;
273 p_sys->bpp = fmt->bits_per_pixel;
274 p_sys->pad = fmt->scanline_pad;
275 p_sys->depth = depth = fmt->depth;
280 msg_Err (vout, "no supported pixmap formats or visual types");
284 msg_Dbg (vout, "using X11 visual ID 0x%"PRIx32, vid);
285 msg_Dbg (vout, " %"PRIu8" bits per pixels, %"PRIu8" bits line pad",
286 p_sys->bpp, p_sys->pad);
288 /* Create colormap (needed to select non-default visual) */
290 if (vid != scr->root_visual)
292 cmap = xcb_generate_id (p_sys->conn);
293 xcb_create_colormap (p_sys->conn, XCB_COLORMAP_ALLOC_NONE,
294 cmap, scr->root, vid);
297 cmap = scr->default_colormap;
301 const uint32_t mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK
303 const uint32_t values[] = {
304 /* XCB_CW_BACK_PIXEL */
306 /* XCB_CW_EVENT_MASK */
307 XCB_EVENT_MASK_BUTTON_PRESS | XCB_EVENT_MASK_BUTTON_RELEASE |
308 XCB_EVENT_MASK_POINTER_MOTION,
309 /* XCB_CW_COLORMAP */
313 xcb_window_t window = xcb_generate_id (p_sys->conn);
315 c = xcb_create_window_checked (p_sys->conn, depth, window,
316 p_sys->embed->handle.xid, 0, 0, 1, 1, 0,
317 XCB_WINDOW_CLASS_INPUT_OUTPUT,
319 if (CheckError (vout, "cannot create X11 window", c))
321 p_sys->window = window;
322 msg_Dbg (vout, "using X11 window %08"PRIx32, p_sys->window);
323 xcb_map_window (p_sys->conn, window);
326 /* Create graphic context (I wonder why the heck do we need this) */
327 p_sys->gc = xcb_generate_id (p_sys->conn);
328 xcb_create_gc (p_sys->conn, p_sys->gc, p_sys->window, 0, NULL);
329 msg_Dbg (vout, "using X11 graphic context %08"PRIx32, p_sys->gc);
331 /* Check shared memory support */
332 p_sys->shm = var_CreateGetBool (vout, "x11-shm") > 0;
335 xcb_shm_query_version_cookie_t ck;
336 xcb_shm_query_version_reply_t *r;
338 ck = xcb_shm_query_version (p_sys->conn);
339 r = xcb_shm_query_version_reply (p_sys->conn, ck, NULL);
342 msg_Err (vout, "shared memory (MIT-SHM) not available");
343 msg_Warn (vout, "display will be slow");
349 vout->pf_init = Init;
350 vout->pf_end = Deinit;
351 vout->pf_display = Display;
352 vout->pf_manage = Manage;
362 * Disconnect from the X server.
364 static void Close (vlc_object_t *obj)
366 vout_thread_t *vout = (vout_thread_t *)obj;
367 vout_sys_t *p_sys = vout->p_sys;
370 vout_ReleaseWindow (p_sys->embed);
371 /* colormap and window are garbage-collected by X */
373 xcb_disconnect (p_sys->conn);
379 xcb_connection_t *conn; /* Shared connection to X server */
380 xcb_image_t *image; /* Picture buffer */
381 xcb_shm_seg_t segment; /* Shared memory segment X ID */
384 #define SHM_ERR ((void *)(intptr_t)(-1))
386 static int PictureInit (vout_thread_t *vout, picture_t *pic)
388 vout_sys_t *p_sys = vout->p_sys;
389 picture_sys_t *priv = malloc (sizeof (*p_sys));
394 assert (pic->i_status == FREE_PICTURE);
395 vout_InitPicture (vout, pic, vout->output.i_chroma,
396 vout->output.i_width, vout->output.i_height,
397 vout->output.i_aspect);
400 const size_t size = pic->p->i_pitch * pic->p->i_lines;
403 { /* Allocate shared memory segment */
404 int id = shmget (IPC_PRIVATE, size, IPC_CREAT | 0700);
408 msg_Err (vout, "shared memory allocation error: %m");
412 /* Attach the segment to VLC */
413 shm = shmat (id, NULL, 0 /* read/write */);
416 msg_Err (vout, "shared memory attachment error: %m");
417 shmctl (id, IPC_RMID, 0);
421 /* Attach the segment to X */
422 xcb_void_cookie_t ck;
424 priv->segment = xcb_generate_id (p_sys->conn);
425 ck = xcb_shm_attach_checked (p_sys->conn, priv->segment, id, 1);
426 shmctl (id, IPC_RMID, 0);
428 if (CheckError (vout, "shared memory server-side error", ck))
430 msg_Info (vout, "using buggy X (remote) server? SSH?");
438 const unsigned real_width = pic->p->i_pitch / (p_sys->bpp >> 3);
439 /* FIXME: anyway to getthing more intuitive than that?? */
442 img = xcb_image_create (real_width, pic->p->i_lines,
443 XCB_IMAGE_FORMAT_Z_PIXMAP, p_sys->pad,
444 p_sys->depth, p_sys->bpp, p_sys->bpp,
445 p_sys->byte_order, XCB_IMAGE_ORDER_MSB_FIRST,
447 (shm != SHM_ERR) ? size : 0,
448 (shm != SHM_ERR) ? shm : NULL);
453 xcb_shm_detach (p_sys->conn, priv->segment);
457 priv->conn = p_sys->conn;
460 pic->p->p_pixels = img->data;
461 pic->i_status = DESTROYED_PICTURE;
462 pic->i_type = DIRECT_PICTURE;
474 * Release picture private data
476 static void PictureDeinit (picture_t *pic)
478 struct picture_sys_t *p_sys = pic->p_sys;
480 if (p_sys->segment != 0)
482 xcb_shm_detach (p_sys->conn, p_sys->segment);
483 shmdt (p_sys->image->data);
485 xcb_image_destroy (p_sys->image);
489 static void get_window_size (xcb_connection_t *conn, xcb_window_t win,
490 unsigned *width, unsigned *height)
492 xcb_get_geometry_cookie_t ck = xcb_get_geometry (conn, win);
493 xcb_get_geometry_reply_t *geo = xcb_get_geometry_reply (conn, ck, NULL);
498 *height = geo->height;
502 *width = *height = 0;
506 * Allocate drawable window and picture buffers.
508 static int Init (vout_thread_t *vout)
510 vout_sys_t *p_sys = vout->p_sys;
511 unsigned x, y, width, height;
513 get_window_size (p_sys->conn, p_sys->embed->handle.xid, &width, &height);
514 vout_PlacePicture (vout, width, height, &x, &y, &width, &height);
516 const uint32_t values[] = { x, y, width, height, };
517 xcb_configure_window (p_sys->conn, p_sys->window,
518 XCB_CONFIG_WINDOW_X | XCB_CONFIG_WINDOW_Y |
519 XCB_CONFIG_WINDOW_WIDTH | XCB_CONFIG_WINDOW_HEIGHT,
522 /* FIXME: I don't get the subtlety between output and fmt_out here */
523 vout->fmt_out.i_visible_width = width;
524 vout->fmt_out.i_visible_height = height;
525 vout->fmt_out.i_sar_num = vout->fmt_out.i_sar_den = 1;
527 vout->output.i_width = vout->fmt_out.i_width =
528 width * vout->fmt_in.i_width / vout->fmt_in.i_visible_width;
529 vout->output.i_height = vout->fmt_out.i_height =
530 height * vout->fmt_in.i_height / vout->fmt_in.i_visible_height;
531 vout->fmt_out.i_x_offset =
532 width * vout->fmt_in.i_x_offset / vout->fmt_in.i_visible_width;
533 p_vout->fmt_out.i_y_offset =
534 height * vout->fmt_in.i_y_offset / vout->fmt_in.i_visible_height;
537 vout->output.i_aspect = vout->fmt_out.i_aspect =
538 width * VOUT_ASPECT_FACTOR / height;
540 /* Allocate picture buffers */
541 I_OUTPUTPICTURES = 0;
542 for (size_t index = 0; I_OUTPUTPICTURES < 2; index++)
544 picture_t *pic = vout->p_picture + index;
546 if (index > sizeof (vout->p_picture) / sizeof (pic))
548 if (pic->i_status != FREE_PICTURE)
550 if (PictureInit (vout, pic))
552 PP_OUTPUTPICTURE[I_OUTPUTPICTURES++] = pic;
554 xcb_flush (p_sys->conn);
559 * Free picture buffers.
561 static void Deinit (vout_thread_t *vout)
563 for (int i = 0; i < I_OUTPUTPICTURES; i++)
564 PictureDeinit (PP_OUTPUTPICTURE[i]);
568 * Sends an image to the X server.
570 static void Display (vout_thread_t *vout, picture_t *pic)
572 vout_sys_t *p_sys = vout->p_sys;
573 picture_sys_t *priv = pic->p_sys;
574 xcb_image_t *img = priv->image;
576 if (img->base == NULL)
578 xcb_shm_segment_info_t info = {
579 .shmseg = priv->segment,
580 .shmid = -1, /* lost track of it, unimportant */
581 .shmaddr = img->data,
584 xcb_image_shm_put (p_sys->conn, p_sys->window, p_sys->gc, img, info,
585 0, 0, 0, 0, img->width, img->height, 0);
588 xcb_image_put (p_sys->conn, p_sys->window, p_sys->gc, img, 0, 0, 0);
589 xcb_flush (p_sys->conn);
593 * Process incoming X events.
595 static int Manage (vout_thread_t *vout)
597 vout_sys_t *p_sys = vout->p_sys;
598 xcb_generic_event_t *ev;
600 while ((ev = xcb_poll_for_event (p_sys->conn)) != NULL)
601 ProcessEvent (vout, p_sys->conn, p_sys->window, ev);
603 if (xcb_connection_has_error (p_sys->conn))
605 msg_Err (vout, "X server failure");