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_aux.h>
37 #include <xcb/xcb_image.h>
39 #include <vlc_common.h>
40 #include <vlc_plugin.h>
42 #include <vlc_window.h>
46 #define DISPLAY_TEXT N_("X11 display")
47 #define DISPLAY_LONGTEXT N_( \
48 "X11 hardware display to use. By default VLC will " \
49 "use the value of the DISPLAY environment variable.")
51 #define SHM_TEXT N_("Use shared memory")
52 #define SHM_LONGTEXT N_( \
53 "Use shared memory to communicate between VLC and the X server.")
55 static int Open (vlc_object_t *);
56 static void Close (vlc_object_t *);
62 set_shortname (N_("XCB"))
63 set_description (N_("(Experimental) XCB video output"))
64 set_category (CAT_VIDEO)
65 set_subcategory (SUBCAT_VIDEO_VOUT)
66 set_capability ("video output", 0)
67 set_callbacks (Open, Close)
69 add_string ("x11-display", NULL, NULL,
70 DISPLAY_TEXT, DISPLAY_LONGTEXT, true)
71 add_bool ("x11-shm", true, NULL, SHM_TEXT, SHM_LONGTEXT, true)
76 xcb_connection_t *conn;
78 vout_window_t *embed; /* VLC window (when windowed) */
80 xcb_visualid_t vid; /* selected visual */
81 xcb_window_t parent; /* parent X window */
82 xcb_colormap_t cmap; /* colormap for selected visual */
83 xcb_window_t window; /* drawable X window */
84 xcb_gcontext_t gc; /* context to put images */
85 bool shm; /* whether to use MIT-SHM */
86 uint8_t bpp; /* bits per pixel */
87 uint8_t pad; /* scanline pad */
90 static int Init (vout_thread_t *);
91 static void Deinit (vout_thread_t *);
92 static void Render (vout_thread_t *, picture_t *);
93 static void Display (vout_thread_t *, picture_t *);
94 static int Manage (vout_thread_t *);
96 int CheckError (vout_thread_t *vout, const char *str, xcb_void_cookie_t ck)
98 xcb_generic_error_t *err;
100 err = xcb_request_check (vout->p_sys->conn, ck);
103 msg_Err (vout, "%s: X11 error %d", str, err->error_code);
112 * Probe the X server.
114 static int Open (vlc_object_t *obj)
116 vout_thread_t *vout = (vout_thread_t *)obj;
117 vout_sys_t *p_sys = malloc (sizeof (*p_sys));
126 char *display = var_CreateGetNonEmptyString (vout, "x11-display");
128 p_sys->conn = xcb_connect (display, &snum);
129 if (xcb_connection_has_error (p_sys->conn) /*== NULL*/)
131 msg_Err (vout, "cannot connect to X server %s",
132 display ? display : "");
138 const xcb_setup_t *setup = xcb_get_setup (p_sys->conn);
140 /* Get the preferred screen */
141 xcb_screen_t *scr = xcb_aux_get_screen (p_sys->conn, snum);
143 assert (p_sys->screen);
144 msg_Dbg (vout, "using screen %d", snum);
146 /* Determine our video format. Normally, this is done in pf_init(), but
147 * this plugin always uses the same format for a given X11 screen. */
150 for (const xcb_format_t *fmt = xcb_setup_pixmap_formats (setup),
151 *end = fmt + xcb_setup_pixmap_formats_length (setup);
154 vlc_fourcc_t chroma = 0;
156 if (fmt->depth < depth)
157 continue; /* We already found a better format! */
159 /* Check that the pixmap format is supported by VLC. */
163 if (fmt->bits_per_pixel == 32)
164 chroma = VLC_FOURCC ('R', 'V', '3', '2');
165 else if (fmt->bits_per_pixel == 24)
166 chroma = VLC_FOURCC ('R', 'V', '2', '4');
171 if (fmt->bits_per_pixel != 16)
173 chroma = VLC_FOURCC ('R', 'V', '1', '6');
176 if (fmt->bits_per_pixel != 16)
178 chroma = VLC_FOURCC ('R', 'V', '1', '5');
181 if (fmt->bits_per_pixel != 8)
183 chroma = VLC_FOURCC ('R', 'G', 'B', '2');
188 if ((fmt->bits_per_pixel << 4) % fmt->scanline_pad)
189 continue; /* VLC pads lines to 16 pixels internally */
191 /* Byte sex is a non-issue for 8-bits. It can be worked around with
192 * RGB masks for 24-bits. Too bad for 15-bits and 16-bits. */
193 #ifdef WORDS_BIGENDIAN
194 # define ORDER XCB_IMAGE_ORDER_MSB_FIRST
196 # define ORDER XCB_IMAGE_ORDER_LSB_FIRST
198 if (fmt->bits_per_pixel == 16 && setup->image_byte_order != ORDER)
201 /* Check that the selected screen supports this depth */
202 xcb_depth_iterator_t it = xcb_screen_allowed_depths_iterator (scr);
203 while (it.rem > 0 && it.data->depth != fmt->depth)
204 xcb_depth_next (&it);
206 continue; /* Depth not supported on this screen */
208 /* Find a visual type for the selected depth */
209 const xcb_visualtype_t *vt = xcb_depth_visuals (it.data);
210 xcb_visualid_t vid = 0;
211 for (int i = xcb_depth_visuals_length (it.data); (i > 0) && !vid; i--)
213 if (vt->_class == XCB_VISUAL_CLASS_TRUE_COLOR)
216 "using TrueColor %"PRIu8"-bits visual ID 0x%0"PRIx32,
217 fmt->depth, vt->visual_id);
222 if (fmt->depth == 8 && vt->_class == XCB_VISUAL_CLASS_STATIC_GRAY)
225 continue; /* Prefer color over gray scale */
227 chroma = VLC_FOURCC ('G', 'R', 'E', 'Y');
229 "using static gray 8-bits visual ID 0x%x"PRIx32,
236 continue; /* The screen does not *really* support this depth */
238 vout->fmt_out.i_chroma = vout->output.i_chroma = chroma;
241 vout->output.i_rmask = vt->red_mask;
242 vout->output.i_gmask = vt->green_mask;
243 vout->output.i_bmask = vt->blue_mask;
246 p_sys->bpp = fmt->bits_per_pixel;
247 p_sys->pad = fmt->scanline_pad;
254 msg_Err (vout, "no supported pixmap formats");
258 msg_Dbg (vout, "using %"PRIu8" bits per pixels (line pad: %"PRIu8")",
259 p_sys->bpp, p_sys->pad);
261 /* Create colormap (needed to select non-default visual) */
262 p_sys->cmap = xcb_generate_id (p_sys->conn);
263 xcb_create_colormap (p_sys->conn, XCB_COLORMAP_ALLOC_NONE,
264 p_sys->cmap, scr->root, p_sys->vid);
266 /* Check shared memory support */
267 p_sys->shm = var_CreateGetBool (vout, "x11-shm") > 0;
270 xcb_shm_query_version_cookie_t ck;
271 xcb_shm_query_version_reply_t *r;
272 xcb_generic_error_t *err;
274 ck = xcb_shm_query_version (p_sys->conn);
275 r = xcb_shm_query_version_reply (p_sys->conn, ck, &err);
278 msg_Err (vout, "shared memory (MIT-SHM) not available");
279 msg_Warn (vout, "display will be slow");
285 /* FIXME: WTH to put as initial width/height values??? */
286 p_sys->embed = vout_RequestXWindow (vout, &(int){ 0 }, &(int){ 0 },
287 &(unsigned){ 0 }, &(unsigned){ 0 });
288 if (p_sys->embed == NULL)
290 msg_Err (vout, "parent window not available");
294 vout->pf_init = Init;
295 vout->pf_end = Deinit;
296 vout->pf_render = Render;
297 vout->pf_display = Display;
298 vout->pf_manage = Manage;
308 * Disconnect from the X server.
310 static void Close (vlc_object_t *obj)
312 vout_thread_t *vout = (vout_thread_t *)obj;
313 vout_sys_t *p_sys = vout->p_sys;
316 vout_ReleaseWindow (p_sys->embed);
317 /* colormap is garbage-ollected by X (?) */
319 xcb_disconnect (p_sys->conn);
325 xcb_connection_t *conn; /* Shared connection to X server */
326 xcb_image_t *image; /* Picture buffer */
327 xcb_image_t *native; /* Rendered picture buffer (in X server format) */
328 xcb_shm_seg_t segment; /* Shared memory segment X ID */
331 #define SHM_ERR ((void *)(intptr_t)(-1))
333 static int PictureInit (vout_thread_t *vout, picture_t *pic)
335 vout_sys_t *p_sys = vout->p_sys;
336 picture_sys_t *priv = malloc (sizeof (*p_sys));
341 assert (pic->i_status == FREE_PICTURE);
342 vout_InitPicture (vout, pic, vout->output.i_chroma,
343 vout->output.i_width, vout->output.i_height,
344 vout->output.i_aspect);
347 const size_t size = pic->p->i_pitch * pic->p->i_lines;
350 { /* Allocate shared memory segment */
351 int id = shmget (IPC_PRIVATE, size, IPC_CREAT | 0700);
355 msg_Err (vout, "shared memory allocation error: %m");
359 /* Attach the segment to VLC */
360 shm = shmat (id, NULL, 0 /* read/write */);
363 msg_Err (vout, "shared memory attachment error: %m");
364 shmctl (id, IPC_RMID, 0);
368 /* Attach the segment to X */
369 xcb_void_cookie_t ck;
371 priv->segment = xcb_generate_id (p_sys->conn);
372 ck = xcb_shm_attach_checked (p_sys->conn, priv->segment, id, 1);
373 shmctl (id, IPC_RMID, 0);
375 if (CheckError (vout, "shared memory server-side error", ck))
377 msg_Info (vout, "using buggy X (remote) server? SSH?");
385 const unsigned real_width = pic->p->i_pitch / (p_sys->bpp >> 3);
386 /* FIXME: anyway to getthing more intuitive than that?? */
389 img = xcb_image_create (real_width, pic->p->i_lines,
390 XCB_IMAGE_FORMAT_Z_PIXMAP, p_sys->pad,
391 p_sys->screen->root_depth, p_sys->bpp, p_sys->bpp,
392 #ifdef WORDS_BIGENDIAN
393 XCB_IMAGE_ORDER_MSB_FIRST,
395 XCB_IMAGE_ORDER_LSB_FIRST,
397 XCB_IMAGE_ORDER_MSB_FIRST,
399 (shm != SHM_ERR) ? size : 0,
400 (shm != SHM_ERR) ? shm : NULL);
405 xcb_shm_detach (p_sys->conn, priv->segment);
408 if (shm != SHM_ERR && xcb_image_native (p_sys->conn, img, 0) == NULL)
409 msg_Warn (vout, "incompatible X server image format");
411 priv->conn = p_sys->conn;
415 pic->p->p_pixels = img->data;
416 pic->i_status = DESTROYED_PICTURE;
417 pic->i_type = DIRECT_PICTURE;
429 * Release picture private data
431 static void PictureDeinit (picture_t *pic)
433 struct picture_sys_t *p_sys = pic->p_sys;
435 if (p_sys->segment != 0)
437 xcb_shm_detach (p_sys->conn, p_sys->segment);
438 shmdt (p_sys->image->data);
440 if ((p_sys->native != NULL) && (p_sys->native != p_sys->image))
441 xcb_image_destroy (p_sys->native);
442 xcb_image_destroy (p_sys->image);
447 * Allocate drawable window and picture buffers.
449 static int Init (vout_thread_t *vout)
451 vout_sys_t *p_sys = vout->p_sys;
452 const xcb_screen_t *screen = p_sys->screen;
453 unsigned x, y, width, height;
455 I_OUTPUTPICTURES = 0;
457 /* Determine parent window and size */
458 if (vout->b_fullscreen)
460 p_sys->parent = screen->root;
461 width = screen->width_in_pixels;
462 height = screen->height_in_pixels;
466 p_sys->parent = p_sys->embed->handle.xid;
468 /* Subscribe to parent window resize events */
469 const uint32_t value = XCB_EVENT_MASK_STRUCTURE_NOTIFY;
470 xcb_change_window_attributes (p_sys->conn, p_sys->parent,
471 XCB_CW_EVENT_MASK, &value);
473 xcb_get_geometry_cookie_t ck;
474 ck = xcb_get_geometry (p_sys->conn, p_sys->parent);
476 xcb_get_geometry_reply_t *geo;
477 xcb_generic_error_t *err;
478 geo = xcb_get_geometry_reply (p_sys->conn, ck, &err);
480 height = geo->height;
484 vout_PlacePicture (vout, width, height, &x, &y, &width, &height);
486 /* FIXME: I don't get the subtlety between output and fmt_out here */
487 vout->fmt_out.i_visible_width = width;
488 vout->fmt_out.i_visible_height = height;
489 vout->fmt_out.i_sar_num = vout->fmt_out.i_sar_den = 1;
491 vout->output.i_width = vout->fmt_out.i_width =
492 width * vout->fmt_in.i_width / vout->fmt_in.i_visible_width;
493 vout->output.i_height = vout->fmt_out.i_height =
494 height * vout->fmt_in.i_height / vout->fmt_in.i_visible_height;
495 vout->fmt_out.i_x_offset =
496 width * vout->fmt_in.i_x_offset / vout->fmt_in.i_visible_width;
497 p_vout->fmt_out.i_y_offset =
498 height * vout->fmt_in.i_y_offset / vout->fmt_in.i_visible_height;
501 vout->output.i_aspect = vout->fmt_out.i_aspect =
502 width * VOUT_ASPECT_FACTOR / height;
505 const uint32_t mask = XCB_CW_BACK_PIXEL | XCB_CW_EVENT_MASK
507 const uint32_t values[] = {
508 /* XCB_CW_BACK_PIXEL */
510 /* XCB_CW_EVENT_MASK */
511 XCB_EVENT_MASK_BUTTON_PRESS | XCB_EVENT_MASK_BUTTON_RELEASE |
512 XCB_EVENT_MASK_POINTER_MOTION,
513 /* XCB_CW_COLORMAP */
517 xcb_window_t window = xcb_generate_id (p_sys->conn);
519 c = xcb_create_window_checked (p_sys->conn, screen->root_depth, window,
520 p_sys->parent, x, y, width, height, 0,
521 XCB_WINDOW_CLASS_INPUT_OUTPUT,
522 p_sys->vid, mask, values);
523 if (CheckError (vout, "cannot create X11 window", c))
525 p_sys->window = window;
526 msg_Dbg (vout, "using X11 window %08"PRIx32, p_sys->window);
527 xcb_map_window (p_sys->conn, window);
529 /* Create graphic context (I wonder why the heck do we need this) */
530 p_sys->gc = xcb_generate_id (p_sys->conn);
531 xcb_create_gc (p_sys->conn, p_sys->gc, p_sys->window, 0, NULL);
532 msg_Dbg (vout, "using X11 graphic context %08"PRIx32, p_sys->gc);
533 xcb_flush (p_sys->conn);
535 /* Allocate picture buffers */
536 I_OUTPUTPICTURES = 0;
537 for (size_t index = 0; I_OUTPUTPICTURES < 2; index++)
539 picture_t *pic = vout->p_picture + index;
541 if (index > sizeof (vout->p_picture) / sizeof (pic))
543 if (pic->i_status != FREE_PICTURE)
545 if (PictureInit (vout, pic))
547 PP_OUTPUTPICTURE[I_OUTPUTPICTURES++] = pic;
558 * Free picture buffers.
560 static void Deinit (vout_thread_t *vout)
562 vout_sys_t *p_sys = vout->p_sys;
564 for (int i = 0; i < I_OUTPUTPICTURES; i++)
565 PictureDeinit (PP_OUTPUTPICTURE[i]);
567 xcb_unmap_window (p_sys->conn, p_sys->window);
568 xcb_destroy_window (p_sys->conn, p_sys->window);
572 * Prepares an image ahead of display.
574 static void Render (vout_thread_t *vout, picture_t *pic)
576 vout_sys_t *p_sys = vout->p_sys;
577 picture_sys_t *priv = pic->p_sys;
579 if ((priv->native != NULL) && (priv->native != priv->image))
580 xcb_image_destroy (priv->native);
581 priv->native = xcb_image_native (p_sys->conn, priv->image, 1);
586 * Sends an image to the X server.
588 static void Display (vout_thread_t *vout, picture_t *pic)
590 vout_sys_t *p_sys = vout->p_sys;
591 picture_sys_t *priv = pic->p_sys;
592 xcb_image_t *img = priv->image, *native = priv->native;
594 if ((native == img) && (img->base == NULL))
596 xcb_shm_segment_info_t info = {
597 .shmseg = priv->segment,
598 .shmid = -1, /* lost track of it, unimportant */
599 .shmaddr = img->data,
602 xcb_image_shm_put (p_sys->conn, p_sys->window, p_sys->gc, img, info,
603 0, 0, 0, 0, img->width, img->height, 0);
607 xcb_image_put (p_sys->conn, p_sys->window, p_sys->gc, native, 0, 0, 0);
608 xcb_flush (p_sys->conn);
612 * Process incoming X events.
614 static int Manage (vout_thread_t *vout)
616 vout_sys_t *p_sys = vout->p_sys;
617 xcb_generic_event_t *ev;
619 while ((ev = xcb_poll_for_event (p_sys->conn)) != NULL)
620 ProcessEvent (vout, p_sys->conn, p_sys->window, ev);
622 if (xcb_connection_has_error (p_sys->conn))
624 msg_Err (vout, "X server failure");