linux_glimp.c

quakeIII源码这个不用我多说吧

  int dga_MajorVersion, dga_MinorVersion;
  int actualWidth, actualHeight;
  int i;
  const char*   glstring; // bk001130 - from cvs1.17 (mkv)

  ri.Printf( PRINT_ALL, "Initializing OpenGL display\n");

  ri.Printf (PRINT_ALL, "...setting mode %d:", mode );

  if ( !R_GetModeInfo( &glConfig.vidWidth, &glConfig.vidHeight, &glConfig.windowAspect, mode ) )
  {
    ri.Printf( PRINT_ALL, " invalid mode\n" );
    return RSERR_INVALID_MODE;
  }
  ri.Printf( PRINT_ALL, " %d %d\n", glConfig.vidWidth, glConfig.vidHeight);

  if (!(dpy = XOpenDisplay(NULL)))
  {
    fprintf(stderr, "Error couldn't open the X display\n");
    return RSERR_INVALID_MODE;
  }
  
  scrnum = DefaultScreen(dpy);
  root = RootWindow(dpy, scrnum);

  actualWidth = glConfig.vidWidth;
  actualHeight = glConfig.vidHeight;

  // Get video mode list
  if (!XF86VidModeQueryVersion(dpy, &vidmode_MajorVersion, &vidmode_MinorVersion))
  {
    vidmode_ext = qfalse;
  } else
  {
    ri.Printf(PRINT_ALL, "Using XFree86-VidModeExtension Version %d.%d\n",
              vidmode_MajorVersion, vidmode_MinorVersion);
    vidmode_ext = qtrue;
  }

  // Check for DGA	
  dga_MajorVersion = 0, dga_MinorVersion = 0;
  if (in_dgamouse->value)
  {
    if (!XF86DGAQueryVersion(dpy, &dga_MajorVersion, &dga_MinorVersion))
    {
      // unable to query, probalby not supported
      ri.Printf( PRINT_ALL, "Failed to detect XF86DGA Mouse\n" );
      ri.Cvar_Set( "in_dgamouse", "0" );
    } else
    {
      ri.Printf( PRINT_ALL, "XF86DGA Mouse (Version %d.%d) initialized\n",
                 dga_MajorVersion, dga_MinorVersion);
    }
  }

  if (vidmode_ext)
  {
    int best_fit, best_dist, dist, x, y;

    XF86VidModeGetAllModeLines(dpy, scrnum, &num_vidmodes, &vidmodes);

    // Are we going fullscreen?  If so, let's change video mode
    if (fullscreen)
    {
      best_dist = 9999999;
      best_fit = -1;

      for (i = 0; i < num_vidmodes; i++)
      {
        if (glConfig.vidWidth > vidmodes[i]->hdisplay ||
            glConfig.vidHeight > vidmodes[i]->vdisplay)
          continue;

        x = glConfig.vidWidth - vidmodes[i]->hdisplay;
        y = glConfig.vidHeight - vidmodes[i]->vdisplay;
        dist = (x * x) + (y * y);
        if (dist < best_dist)
        {
          best_dist = dist;
          best_fit = i;
        }
      }

      if (best_fit != -1)
      {
        actualWidth = vidmodes[best_fit]->hdisplay;
        actualHeight = vidmodes[best_fit]->vdisplay;

        // change to the mode
        XF86VidModeSwitchToMode(dpy, scrnum, vidmodes[best_fit]);
        vidmode_active = qtrue;

        // Move the viewport to top left
        XF86VidModeSetViewPort(dpy, scrnum, 0, 0);

        ri.Printf(PRINT_ALL, "XFree86-VidModeExtension Activated at %dx%d\n",
                  actualWidth, actualHeight);

      } else
      {
        fullscreen = 0;
        ri.Printf(PRINT_ALL, "XFree86-VidModeExtension: No acceptable modes found\n");
      }
    } else
    {
      ri.Printf(PRINT_ALL, "XFree86-VidModeExtension:  Ignored on non-fullscreen/Voodoo\n");
    }
  }


  if (!r_colorbits->value)
    colorbits = 24;
  else
    colorbits = r_colorbits->value;

  if ( !Q_stricmp( r_glDriver->string, _3DFX_DRIVER_NAME ) )
    colorbits = 16;

  if (!r_depthbits->value)
    depthbits = 24;
  else
    depthbits = r_depthbits->value;
  stencilbits = r_stencilbits->value;

  for (i = 0; i < 16; i++)
  {
    // 0 - default
    // 1 - minus colorbits
    // 2 - minus depthbits
    // 3 - minus stencil
    if ((i % 4) == 0 && i)
    {
      // one pass, reduce
      switch (i / 4)
      {
      case 2 :
        if (colorbits == 24)
          colorbits = 16;
        break;
      case 1 :
        if (depthbits == 24)
          depthbits = 16;
        else if (depthbits == 16)
          depthbits = 8;
      case 3 :
        if (stencilbits == 24)
          stencilbits = 16;
        else if (stencilbits == 16)
          stencilbits = 8;
      }
    }

    tcolorbits = colorbits;
    tdepthbits = depthbits;
    tstencilbits = stencilbits;

    if ((i % 4) == 3)
    { // reduce colorbits
      if (tcolorbits == 24)
        tcolorbits = 16;
    }

    if ((i % 4) == 2)
    { // reduce depthbits
      if (tdepthbits == 24)
        tdepthbits = 16;
      else if (tdepthbits == 16)
        tdepthbits = 8;
    }

    if ((i % 4) == 1)
    { // reduce stencilbits
      if (tstencilbits == 24)
        tstencilbits = 16;
      else if (tstencilbits == 16)
        tstencilbits = 8;
      else
        tstencilbits = 0;
    }

    if (tcolorbits == 24)
    {
      attrib[ATTR_RED_IDX] = 8;
      attrib[ATTR_GREEN_IDX] = 8;
      attrib[ATTR_BLUE_IDX] = 8;
    } else
    {
      // must be 16 bit
      attrib[ATTR_RED_IDX] = 4;
      attrib[ATTR_GREEN_IDX] = 4;
      attrib[ATTR_BLUE_IDX] = 4;
    }

    attrib[ATTR_DEPTH_IDX] = tdepthbits; // default to 24 depth
    attrib[ATTR_STENCIL_IDX] = tstencilbits;

    visinfo = qglXChooseVisual(dpy, scrnum, attrib);
    if (!visinfo)
    {
      continue;
    }

    ri.Printf( PRINT_ALL, "Using %d/%d/%d Color bits, %d depth, %d stencil display.\n", 
               attrib[ATTR_RED_IDX], attrib[ATTR_GREEN_IDX], attrib[ATTR_BLUE_IDX],
               attrib[ATTR_DEPTH_IDX], attrib[ATTR_STENCIL_IDX]);

    glConfig.colorBits = tcolorbits;
    glConfig.depthBits = tdepthbits;
    glConfig.stencilBits = tstencilbits;
    break;
  }

  if (!visinfo)
  {
    ri.Printf( PRINT_ALL, "Couldn't get a visual\n" );
    return RSERR_INVALID_MODE;
  }

  /* window attributes */
  attr.background_pixel = BlackPixel(dpy, scrnum);
  attr.border_pixel = 0;
  attr.colormap = XCreateColormap(dpy, root, visinfo->visual, AllocNone);
  attr.event_mask = X_MASK;
  if (vidmode_active)
  {
    mask = CWBackPixel | CWColormap | CWSaveUnder | CWBackingStore | 
           CWEventMask | CWOverrideRedirect;
    attr.override_redirect = True;
    attr.backing_store = NotUseful;
    attr.save_under = False;
  } else
    mask = CWBackPixel | CWBorderPixel | CWColormap | CWEventMask;

  win = XCreateWindow(dpy, root, 0, 0, 
                      actualWidth, actualHeight, 
                      0, visinfo->depth, InputOutput,
                      visinfo->visual, mask, &attr);

  XStoreName( dpy, win, WINDOW_CLASS_NAME );

  /* GH: Don't let the window be resized */
  sizehints.flags = PMinSize | PMaxSize;
  sizehints.min_width = sizehints.max_width = actualWidth;
  sizehints.min_height = sizehints.max_height = actualHeight;

  XSetWMNormalHints( dpy, win, &sizehints );

  XMapWindow( dpy, win );

  if (vidmode_active)
    XMoveWindow(dpy, win, 0, 0);

  XFlush(dpy);
  XSync(dpy,False); // bk001130 - from cvs1.17 (mkv)
  ctx = qglXCreateContext(dpy, visinfo, NULL, True);
  XSync(dpy,False); // bk001130 - from cvs1.17 (mkv)

  /* GH: Free the visinfo after we're done with it */
  XFree( visinfo );

  qglXMakeCurrent(dpy, win, ctx);

  // bk001130 - from cvs1.17 (mkv)
  glstring = qglGetString (GL_RENDERER);
  ri.Printf( PRINT_ALL, "GL_RENDERER: %s\n", glstring );

  // bk010122 - new software token (Indirect)
  if ( !Q_stricmp( glstring, "Mesa X11")
       || !Q_stricmp( glstring, "Mesa GLX Indirect") )
  {
    if ( !r_allowSoftwareGL->integer )
    {
      ri.Printf( PRINT_ALL, "\n\n***********************************************************\n" );
      ri.Printf( PRINT_ALL, " You are using software Mesa (no hardware acceleration)!   \n" );
      ri.Printf( PRINT_ALL, " Driver DLL used: %s\n", drivername ); 
      ri.Printf( PRINT_ALL, " If this is intentional, add\n" );
      ri.Printf( PRINT_ALL, "       \"+set r_allowSoftwareGL 1\"\n" );
      ri.Printf( PRINT_ALL, " to the command line when starting the game.\n" );
      ri.Printf( PRINT_ALL, "***********************************************************\n");
      GLimp_Shutdown( );
      return RSERR_INVALID_MODE;
    } else
    {
      ri.Printf( PRINT_ALL, "...using software Mesa (r_allowSoftwareGL==1).\n" );
    }
  }

  return RSERR_OK;
}

/*
** GLW_InitExtensions
*/
static void GLW_InitExtensions( void )
{
  if ( !r_allowExtensions->integer )
  {
    ri.Printf( PRINT_ALL, "*** IGNORING OPENGL EXTENSIONS ***\n" );
    return;
  }

  ri.Printf( PRINT_ALL, "Initializing OpenGL extensions\n" );

  // GL_S3_s3tc
  if ( Q_stristr( glConfig.extensions_string, "GL_S3_s3tc" ) )
  {
    if ( r_ext_compressed_textures->value )
    {
      glConfig.textureCompression = TC_S3TC;
      ri.Printf( PRINT_ALL, "...using GL_S3_s3tc\n" );
    } else
    {
      glConfig.textureCompression = TC_NONE;
      ri.Printf( PRINT_ALL, "...ignoring GL_S3_s3tc\n" );
    }
  } else
  {
    glConfig.textureCompression = TC_NONE;
    ri.Printf( PRINT_ALL, "...GL_S3_s3tc not found\n" );
  }

  // GL_EXT_texture_env_add
  glConfig.textureEnvAddAvailable = qfalse;
  if ( Q_stristr( glConfig.extensions_string, "EXT_texture_env_add" ) )
  {
    if ( r_ext_texture_env_add->integer )
    {
      glConfig.textureEnvAddAvailable = qtrue;
      ri.Printf( PRINT_ALL, "...using GL_EXT_texture_env_add\n" );
    } else
    {
      glConfig.textureEnvAddAvailable = qfalse;
      ri.Printf( PRINT_ALL, "...ignoring GL_EXT_texture_env_add\n" );
    }
  } else
  {
    ri.Printf( PRINT_ALL, "...GL_EXT_texture_env_add not found\n" );
  }

  // GL_ARB_multitexture
  qglMultiTexCoord2fARB = NULL;
  qglActiveTextureARB = NULL;
  qglClientActiveTextureARB = NULL;
  if ( Q_stristr( glConfig.extensions_string, "GL_ARB_multitexture" ) )
  {
    if ( r_ext_multitexture->value )
    {
      qglMultiTexCoord2fARB = ( PFNGLMULTITEXCOORD2FARBPROC ) dlsym( glw_state.OpenGLLib, "glMultiTexCoord2fARB" );
      qglActiveTextureARB = ( PFNGLACTIVETEXTUREARBPROC ) dlsym( glw_state.OpenGLLib, "glActiveTextureARB" );
      qglClientActiveTextureARB = ( PFNGLCLIENTACTIVETEXTUREARBPROC ) dlsym( glw_state.OpenGLLib, "glClientActiveTextureARB" );

      if ( qglActiveTextureARB )
      {
        qglGetIntegerv( GL_MAX_ACTIVE_TEXTURES_ARB, &glConfig.maxActiveTextures );

        if ( glConfig.maxActiveTextures > 1 )
        {
          ri.Printf( PRINT_ALL, "...using GL_ARB_multitexture\n" );
        } else
        {
          qglMultiTexCoord2fARB = NULL;
          qglActiveTextureARB = NULL;
          qglClientActiveTextureARB = NULL;
          ri.Printf( PRINT_ALL, "...not using GL_ARB_multitexture, < 2 texture units\n" );
        }
      }
    } else
    {
      ri.Printf( PRINT_ALL, "...ignoring GL_ARB_multitexture\n" );
    }
  } else
  {
    ri.Printf( PRINT_ALL, "...GL_ARB_multitexture not found\n" );
  }

  // GL_EXT_compiled_vertex_array
  if ( Q_stristr( glConfig.extensions_string, "GL_EXT_compiled_vertex_array" ) )
  {
    if ( r_ext_compiled_vertex_array->value )
    {
      ri.Printf( PRINT_ALL, "...using GL_EXT_compiled_vertex_array\n" );
      qglLockArraysEXT = ( void ( APIENTRY * )( int, int ) ) dlsym( glw_state.OpenGLLib, "glLockArraysEXT" );
      qglUnlockArraysEXT = ( void ( APIENTRY * )( void ) ) dlsym( glw_state.OpenGLLib, "glUnlockArraysEXT" );
      if (!qglLockArraysEXT || !qglUnlockArraysEXT)
      {
        ri.Error (ERR_FATAL, "bad getprocaddress");
      }
    } else
    {
      ri.Printf( PRINT_ALL, "...ignoring GL_EXT_compiled_vertex_array\n" );
    }
  } else
  {
    ri.Printf( PRINT_ALL, "...GL_EXT_compiled_vertex_array not found\n" );
  }

}

static void GLW_InitGamma()
{
  /* Minimum extension version required */
  #define GAMMA_MINMAJOR 2
  #define GAMMA_MINMINOR 0
  
  glConfig.deviceSupportsGamma = qfalse;

  if (vidmode_ext)
  {
    if (vidmode_MajorVersion < GAMMA_MINMAJOR || 
        (vidmode_MajorVersion == GAMMA_MINMAJOR && vidmode_MinorVersion < GAMMA_MINMINOR)) {
      ri.Printf( PRINT_ALL, "XF86 Gamma extension not supported in this version\n");
      return;
    }
    XF86VidModeGetGamma(dpy, scrnum, &vidmode_InitialGamma);
    ri.Printf( PRINT_ALL, "XF86 Gamma extension initialized\n");
    glConfig.deviceSupportsGamma = qtrue;
  }
}

/*
** GLW_LoadOpenGL
**
** GLimp_win.c internal function that that attempts to load and use 
** a specific OpenGL DLL.
*/
static qboolean GLW_LoadOpenGL( const char *name )
{
  qboolean fullscreen;

  ri.Printf( PRINT_ALL, "...loading %s: ", name );

  // disable the 3Dfx splash screen and set gamma
  // we do this all the time, but it shouldn't hurt anything
  // on non-3Dfx stuff
  putenv("FX_GLIDE_NO_SPLASH=0");

  // Mesa VooDoo hacks
  putenv("MESA_GLX_FX=fullscreen\n");

  // load the QGL layer
  if ( QGL_Init( name ) )
  {
    fullscreen = r_fullscreen->integer;

    // create the window and set up the context
    if ( !GLW_StartDriverAndSetMode( name, r_mode->integer, fullscreen ) )