modules/video_output/glx.c

   1 /**
   2  * @file glx.c
   3  * @brief GLX OpenGL extension module
   4  */
   5 /*****************************************************************************
   6  * Copyright © 2010-2012 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 #include <GL/glx.h>
  30 #include <GL/glxext.h>
  31
  32 #include <vlc_common.h>
  33 #include <vlc_plugin.h>
  34 #include <vlc_opengl.h>
  35 #include <vlc_vout_window.h>
  36 #include <vlc_xlib.h>
  37
  38 typedef struct vlc_gl_sys_t
  39 {
  40     Display *display;
  41     GLXWindow win;
  42     GLXContext ctx;
  43 } vlc_gl_sys_t;
  44
  45 static int MakeCurrent (vlc_gl_t *gl)
  46 {
  47     vlc_gl_sys_t *sys = gl->sys;
  48
  49     if (!glXMakeContextCurrent (sys->display, sys->win, sys->win, sys->ctx))
  50         return VLC_EGENERIC;
  51     return VLC_SUCCESS;
  52 }
  53
  54 static void ReleaseCurrent (vlc_gl_t *gl)
  55 {
  56     vlc_gl_sys_t *sys = gl->sys;
  57
  58     glXMakeContextCurrent (sys->display, None, None, NULL);
  59 }
  60
  61 static void SwapBuffers (vlc_gl_t *gl)
  62 {
  63     vlc_gl_sys_t *sys = gl->sys;
  64
  65     glXSwapBuffers (sys->display, sys->win);
  66 }
  67
  68 static void *GetSymbol(vlc_gl_t *gl, const char *procname)
  69 {
  70     (void) gl;
  71 #ifdef GLX_ARB_get_proc_address
  72     return glXGetProcAddressARB ((const GLubyte *)procname);
  73 #else
  74     return NULL;
  75 #endif
  76 }
  77
  78 static bool CheckGLX (vlc_object_t *vd, Display *dpy)
  79 {
  80     int major, minor;
  81     bool ok = false;
  82
  83     if (!glXQueryVersion (dpy, &major, &minor))
  84         msg_Dbg (vd, "GLX extension not available");
  85     else
  86     if (major != 1)
  87         msg_Dbg (vd, "GLX extension version %d.%d unknown", major, minor);
  88     else
  89     if (minor < 3)
  90         msg_Dbg (vd, "GLX extension version %d.%d too old", major, minor);
  91     else
  92     {
  93         msg_Dbg (vd, "using GLX extension version %d.%d", major, minor);
  94         ok = true;
  95     }
  96     return ok;
  97 }
  98
  99 static bool CheckGLXext (Display *dpy, unsigned snum, const char *ext)
 100 {
 101     const char *exts = glXQueryExtensionsString (dpy, snum);
 102     const size_t extlen = strlen (ext);
 103
 104     while (*exts)
 105     {
 106         exts += strspn (exts, " ");
 107
 108         size_t len = strcspn (exts, " ");
 109         if (len == extlen && !memcmp (exts, ext, extlen))
 110             return true;
 111         exts += len;
 112     }
 113     return false;
 114 }
 115
 116 static int Open (vlc_object_t *obj)
 117 {
 118     vlc_gl_t *gl = (vlc_gl_t *)obj;
 119
 120     if (gl->surface->type != VOUT_WINDOW_TYPE_XID || !vlc_xlib_init (obj))
 121         return VLC_EGENERIC;
 122
 123     /* Initialize GLX display */
 124     Display *dpy = XOpenDisplay (gl->surface->display.x11);
 125     if (dpy == NULL)
 126         return VLC_EGENERIC;
 127
 128     vlc_gl_sys_t *sys = malloc (sizeof (*sys));
 129     if (unlikely(sys == NULL))
 130     {
 131         XCloseDisplay (dpy);
 132         return VLC_ENOMEM;
 133     }
 134     gl->sys = sys;
 135     sys->display = dpy;
 136
 137     if (!CheckGLX (obj, dpy))
 138         goto error;
 139
 140     /* Determine our pixel format */
 141     XWindowAttributes wa;
 142     if (!XGetWindowAttributes (dpy, gl->surface->handle.xid, &wa))
 143         goto error;
 144
 145     const int snum = XScreenNumberOfScreen (wa.screen);
 146     const VisualID visual = XVisualIDFromVisual (wa.visual);
 147     static const int attr[] = {
 148         GLX_RED_SIZE, 5,
 149         GLX_GREEN_SIZE, 5,
 150         GLX_BLUE_SIZE, 5,
 151         GLX_DOUBLEBUFFER, True,
 152         GLX_X_RENDERABLE, True,
 153         GLX_DRAWABLE_TYPE, GLX_WINDOW_BIT,
 154         None
 155     };
 156
 157     int nelem;
 158     GLXFBConfig *confs = glXChooseFBConfig (dpy, snum, attr, &nelem);
 159     if (confs == NULL)
 160     {
 161         msg_Err (obj, "cannot choose GLX frame buffer configurations");
 162         goto error;
 163     }
 164
 165     GLXFBConfig conf;
 166     bool found = false;
 167     for (int i = 0; i < nelem && !found; i++)
 168     {
 169         conf = confs[i];
 170
 171         XVisualInfo *vi = glXGetVisualFromFBConfig (dpy, conf);
 172         if (vi == NULL)
 173             continue;
 174
 175         if (vi->visualid == visual)
 176             found = true;
 177         XFree (vi);
 178     }
 179     XFree (confs);
 180
 181     if (!found)
 182     {
 183         msg_Err (obj, "cannot match GLX frame buffer configuration");
 184         goto error;
 185     }
 186
 187     /* Create a drawing surface */
 188     sys->win = glXCreateWindow (dpy, conf, gl->surface->handle.xid, NULL);
 189     if (sys->win == None)
 190     {
 191         msg_Err (obj, "cannot create GLX window");
 192         goto error;
 193     }
 194
 195     /* Create an OpenGL context */
 196     sys->ctx = glXCreateNewContext (dpy, conf, GLX_RGBA_TYPE, NULL, True);
 197     if (sys->ctx == NULL)
 198     {
 199         glXDestroyWindow (dpy, sys->win);
 200         msg_Err (obj, "cannot create GLX context");
 201         goto error;
 202     }
 203
 204     /* Initialize OpenGL callbacks */
 205     gl->sys = sys;
 206     gl->makeCurrent = MakeCurrent;
 207     gl->releaseCurrent = ReleaseCurrent;
 208     gl->resize = NULL;
 209     gl->swap = SwapBuffers;
 210     gl->getProcAddress = GetSymbol;
 211
 212 #ifdef GLX_ARB_get_proc_address
 213     bool is_swap_interval_set = false;
 214
 215     MakeCurrent (gl);
 216 # ifdef GLX_SGI_swap_control
 217     if (!is_swap_interval_set
 218      && CheckGLXext (dpy, snum, "GLX_SGI_swap_control"))
 219     {
 220         PFNGLXSWAPINTERVALSGIPROC SwapIntervalSGI = (PFNGLXSWAPINTERVALSGIPROC)
 221             glXGetProcAddressARB ((const GLubyte *)"glXSwapIntervalSGI");
 222         assert (SwapIntervalSGI != NULL);
 223         is_swap_interval_set = !SwapIntervalSGI (1);
 224     }
 225 # endif
 226 # ifdef GLX_EXT_swap_control
 227     if (!is_swap_interval_set
 228      && CheckGLXext (dpy, snum, "GLX_EXT_swap_control"))
 229     {
 230         PFNGLXSWAPINTERVALEXTPROC SwapIntervalEXT = (PFNGLXSWAPINTERVALEXTPROC)
 231             glXGetProcAddress ((const GLubyte *)"glXSwapIntervalEXT");
 232         assert (SwapIntervalEXT != NULL);
 233         SwapIntervalEXT (dpy, sys->win, 1);
 234         is_swap_interval_set = true;
 235     }
 236 # endif
 237     ReleaseCurrent (gl);
 238 #endif
 239
 240     return VLC_SUCCESS;
 241
 242 error:
 243     XCloseDisplay (dpy);
 244     free (sys);
 245     return VLC_EGENERIC;
 246 }
 247
 248 static void Close (vlc_object_t *obj)
 249 {
 250     vlc_gl_t *gl = (vlc_gl_t *)obj;
 251     vlc_gl_sys_t *sys = gl->sys;
 252     Display *dpy = sys->display;
 253
 254     glXDestroyContext (dpy, sys->ctx);
 255     glXDestroyWindow (dpy, sys->win);
 256     XCloseDisplay (dpy);
 257     free (sys);
 258 }
 259
 260 vlc_module_begin ()
 261     set_shortname (N_("GLX"))
 262     set_description (N_("GLX extension for OpenGL"))
 263     set_category (CAT_VIDEO)
 264     set_subcategory (SUBCAT_VIDEO_VOUT)
 265     set_capability ("opengl", 20)
 266     set_callbacks (Open, Close)
 267 vlc_module_end ()