xm_api.c

mesa-6.5-minigui源码

/*
 * Find an XMesaBuffer by matching X display and colormap but NOT matching
 * the notThis buffer.
 */
static XMesaBuffer find_xmesa_buffer(XMesaDisplay *dpy,
                                     XMesaColormap cmap,
                                     XMesaBuffer notThis)
{
   XMesaBuffer b;
   for (b=XMesaBufferList; b; b=b->Next) {
      if (b->display==dpy && b->cmap==cmap && b!=notThis) {
         return b;
      }
   }
   return NULL;
}


/*
 * Free an XMesaBuffer, remove from linked list, perhaps free X colormap
 * entries.
 */
static void free_xmesa_buffer(int client, XMesaBuffer buffer)
{
   XMesaBuffer prev = NULL, b;
   (void) client;
   for (b=XMesaBufferList; b; b=b->Next) {
      if (b==buffer) {
         /* unlink bufer from list */
         if (prev)
            prev->Next = buffer->Next;
         else
            XMesaBufferList = buffer->Next;
         /* Check to free X colors */
         if (buffer->num_alloced>0) {
            /* If no other buffer uses this X colormap then free the colors. */
            if (!find_xmesa_buffer(buffer->display, buffer->cmap, buffer)) {
#ifdef XFree86Server
               (void)FreeColors(buffer->cmap, client,
				buffer->num_alloced, buffer->alloced_colors,
				0);
#else
               XFreeColors(buffer->display, buffer->cmap,
                           buffer->alloced_colors, buffer->num_alloced, 0);
#endif
            }
         }

         _mesa_free_framebuffer_data(&buffer->mesa_buffer);
         _mesa_free(buffer);

         return;
      }
      /* continue search */
      prev = b;
   }
   /* buffer not found in XMesaBufferList */
   _mesa_problem(NULL,"free_xmesa_buffer() - buffer not found\n");
}


/* Copy X color table stuff from one XMesaBuffer to another. */
static void copy_colortable_info(XMesaBuffer dst, const XMesaBuffer src)
{
   MEMCPY(dst->color_table, src->color_table, sizeof(src->color_table));
   MEMCPY(dst->pixel_to_r, src->pixel_to_r, sizeof(src->pixel_to_r));
   MEMCPY(dst->pixel_to_g, src->pixel_to_g, sizeof(src->pixel_to_g));
   MEMCPY(dst->pixel_to_b, src->pixel_to_b, sizeof(src->pixel_to_b));
   dst->num_alloced = src->num_alloced;
   MEMCPY(dst->alloced_colors, src->alloced_colors,
          sizeof(src->alloced_colors));
}



/**********************************************************************/
/*****                   Misc Private Functions                   *****/
/**********************************************************************/


/**
 * Allocate a shared memory XImage back buffer for the given XMesaBuffer.
 * Return:  GL_TRUE if success, GL_FALSE if error
 */
#ifndef XFree86Server
static GLboolean
alloc_shm_back_buffer(XMesaBuffer b, GLuint width, GLuint height)
{
#ifdef USE_XSHM
   /*
    * We have to do a _lot_ of error checking here to be sure we can
    * really use the XSHM extension.  It seems different servers trigger
    * errors at different points if the extension won't work.  Therefore
    * we have to be very careful...
    */
   GC gc;
   int (*old_handler)( XMesaDisplay *, XErrorEvent * );

   if (width == 0 || height == 0) {
      /* this will be true the first time we're called on 'b' */
      return GL_FALSE;
   }

   b->backxrb->ximage = XShmCreateImage(b->xm_visual->display,
                                        b->xm_visual->visinfo->visual,
                                        b->xm_visual->visinfo->depth,
                                        ZPixmap, NULL, &b->shminfo,
                                        width, height);
   if (b->backxrb->ximage == NULL) {
      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (XShmCreateImage), disabling.\n");
      b->shm = 0;
      return GL_FALSE;
   }

   b->shminfo.shmid = shmget( IPC_PRIVATE, b->backxrb->ximage->bytes_per_line
			     * b->backxrb->ximage->height, IPC_CREAT|0777 );
   if (b->shminfo.shmid < 0) {
      _mesa_warning(NULL, "shmget failed while allocating back buffer.\n");
      XDestroyImage( b->backxrb->ximage );
      b->backxrb->ximage = NULL;
      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (shmget), disabling.\n");
      b->shm = 0;
      return GL_FALSE;
   }

   b->shminfo.shmaddr = b->backxrb->ximage->data
                      = (char*)shmat( b->shminfo.shmid, 0, 0 );
   if (b->shminfo.shmaddr == (char *) -1) {
      _mesa_warning(NULL, "shmat() failed while allocating back buffer.\n");
      XDestroyImage( b->backxrb->ximage );
      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
      b->backxrb->ximage = NULL;
      _mesa_warning(NULL, "alloc_back_buffer: Shared memory error (shmat), disabling.\n");
      b->shm = 0;
      return GL_FALSE;
   }

   b->shminfo.readOnly = False;
   mesaXErrorFlag = 0;
   old_handler = XSetErrorHandler( mesaHandleXError );
   /* This may trigger the X protocol error we're ready to catch: */
   XShmAttach( b->xm_visual->display, &b->shminfo );
   XSync( b->xm_visual->display, False );

   if (mesaXErrorFlag) {
      /* we are on a remote display, this error is normal, don't print it */
      XFlush( b->xm_visual->display );
      mesaXErrorFlag = 0;
      XDestroyImage( b->backxrb->ximage );
      shmdt( b->shminfo.shmaddr );
      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
      b->backxrb->ximage = NULL;
      b->shm = 0;
      (void) XSetErrorHandler( old_handler );
      return GL_FALSE;
   }

   shmctl( b->shminfo.shmid, IPC_RMID, 0 ); /* nobody else needs it */

   /* Finally, try an XShmPutImage to be really sure the extension works */
   gc = XCreateGC( b->xm_visual->display, b->frontxrb->drawable, 0, NULL );
   XShmPutImage( b->xm_visual->display, b->frontxrb->drawable, gc,
		 b->backxrb->ximage, 0, 0, 0, 0, 1, 1 /*one pixel*/, False );
   XSync( b->xm_visual->display, False );
   XFreeGC( b->xm_visual->display, gc );
   (void) XSetErrorHandler( old_handler );
   if (mesaXErrorFlag) {
      XFlush( b->xm_visual->display );
      mesaXErrorFlag = 0;
      XDestroyImage( b->backxrb->ximage );
      shmdt( b->shminfo.shmaddr );
      shmctl( b->shminfo.shmid, IPC_RMID, 0 );
      b->backxrb->ximage = NULL;
      b->shm = 0;
      return GL_FALSE;
   }

   return GL_TRUE;
#else
   /* Can't compile XSHM support */
   return GL_FALSE;
#endif
}
#endif




/*
 * Setup an off-screen pixmap or Ximage to use as the back buffer.
 * Input:  b - the X/Mesa buffer
 */
void
xmesa_alloc_back_buffer( XMesaBuffer b, GLuint width, GLuint height )
{
   if (width == 0 || height == 0)
      return;

   if (b->db_mode == BACK_XIMAGE) {
      /* Deallocate the old backxrb->ximage, if any */
      if (b->backxrb->ximage) {
#if defined(USE_XSHM) && !defined(XFree86Server)
	 if (b->shm) {
	    XShmDetach( b->xm_visual->display, &b->shminfo );
	    XDestroyImage( b->backxrb->ximage );
	    shmdt( b->shminfo.shmaddr );
	 }
	 else
#endif
	   XMesaDestroyImage( b->backxrb->ximage );
	 b->backxrb->ximage = NULL;
      }

      /* Allocate new back buffer */
#ifdef XFree86Server
      /* Allocate a regular XImage for the back buffer. */
      b->backxrb->ximage = XMesaCreateImage(b->xm_visual->BitsPerPixel,
                                            width, height, NULL);
      {
#else
      if (b->shm == 0 || !alloc_shm_back_buffer(b, width, height)) {
	 /* Allocate a regular XImage for the back buffer. */
	 b->backxrb->ximage = XCreateImage( b->xm_visual->display,
                                      b->xm_visual->visinfo->visual,
                                      GET_VISUAL_DEPTH(b->xm_visual),
				      ZPixmap, 0,   /* format, offset */
				      NULL,
                                      width, height,
				      8, 0 );  /* pad, bytes_per_line */
#endif
	 if (!b->backxrb->ximage) {
	    _mesa_warning(NULL, "alloc_back_buffer: XCreateImage failed.\n");
            return;
	 }
         b->backxrb->ximage->data = (char *) MALLOC( b->backxrb->ximage->height
                                        * b->backxrb->ximage->bytes_per_line );
         if (!b->backxrb->ximage->data) {
            _mesa_warning(NULL, "alloc_back_buffer: MALLOC failed.\n");
            XMesaDestroyImage( b->backxrb->ximage );
            b->backxrb->ximage = NULL;
         }
         else {
            /* this call just updates the width/origin fields in the xrb */
            b->backxrb->Base.AllocStorage(NULL, &b->backxrb->Base, 
                                          b->backxrb->Base.InternalFormat,
                                          b->backxrb->ximage->width,
                                          b->backxrb->ximage->height);
         }
      }
      b->backxrb->pixmap = None;
   }
   else if (b->db_mode == BACK_PIXMAP) {
      if (!width)
         width = 1;
      if (!height)
         height = 1;

      /* Free the old back pixmap */
      if (b->backxrb->pixmap) {
	 XMesaFreePixmap( b->xm_visual->display, b->backxrb->pixmap );
      }
      /* Allocate new back pixmap */
      b->backxrb->pixmap = XMesaCreatePixmap( b->xm_visual->display,
                                              b->frontxrb->drawable,
                                              width, height,
                                              GET_VISUAL_DEPTH(b->xm_visual) );
      b->backxrb->ximage = NULL;
   }
}



/*
 * A replacement for XAllocColor.  This function should never
 * fail to allocate a color.  When XAllocColor fails, we return
 * the nearest matching color.  If we have to allocate many colors
 * this function isn't too efficient; the XQueryColors() could be
 * done just once.
 * Written by Michael Pichler, Brian Paul, Mark Kilgard
 * Input:  dpy - X display
 *         cmap - X colormap
 *         cmapSize - size of colormap
 * In/Out: color - the XColor struct
 * Output:  exact - 1=exact color match, 0=closest match
 *          alloced - 1=XAlloc worked, 0=XAlloc failed
 */
static void
noFaultXAllocColor( int client,
                    XMesaDisplay *dpy,
                    XMesaColormap cmap,
                    int cmapSize,
                    XMesaColor *color,
                    int *exact, int *alloced )
{
#ifdef XFree86Server
   Pixel *ppixIn;
   xrgb *ctable;
#else
   /* we'll try to cache ctable for better remote display performance */
   static Display *prevDisplay = NULL;
   static XMesaColormap prevCmap = 0;
   static int prevCmapSize = 0;
   static XMesaColor *ctable = NULL;
#endif
   XMesaColor subColor;
   int i, bestmatch;
   double mindist;       /* 3*2^16^2 exceeds long int precision. */

   (void) client;

   /* First try just using XAllocColor. */
#ifdef XFree86Server
   if (AllocColor(cmap,
		  &color->red, &color->green, &color->blue,
		  &color->pixel,
		  client) == Success) {
#else
   if (XAllocColor(dpy, cmap, color)) {
#endif
      *exact = 1;
      *alloced = 1;
      return;
   }

   /* Alloc failed, search for closest match */

   /* Retrieve color table entries. */
   /* XXX alloca candidate. */
#ifdef XFree86Server
   ppixIn = (Pixel *) MALLOC(cmapSize * sizeof(Pixel));
   ctable = (xrgb *) MALLOC(cmapSize * sizeof(xrgb));
   for (i = 0; i < cmapSize; i++) {
      ppixIn[i] = i;
   }
   QueryColors(cmap, cmapSize, ppixIn, ctable);
#else
   if (prevDisplay != dpy || prevCmap != cmap
       || prevCmapSize != cmapSize || !ctable) {
      /* free previously cached color table */
      if (ctable)
         _mesa_free(ctable);
      /* Get the color table from X */
      ctable = (XMesaColor *) MALLOC(cmapSize * sizeof(XMesaColor));
      assert(ctable);
      for (i = 0; i < cmapSize; i++) {
         ctable[i].pixel = i;
      }
      XQueryColors(dpy, cmap, ctable, cmapSize);
      prevDisplay = dpy;
      prevCmap = cmap;
      prevCmapSize = cmapSize;
   }
#endif

   /* Find best match. */
   bestmatch = -1;
   mindist = 0.0;
   for (i = 0; i < cmapSize; i++) {
      double dr = 0.30 * ((double) color->red - (double) ctable[i].red);
      double dg = 0.59 * ((double) color->green - (double) ctable[i].green);
      double db = 0.11 * ((double) color->blue - (double) ctable[i].blue);
      double dist = dr * dr + dg * dg + db * db;
      if (bestmatch < 0 || dist < mindist) {
         bestmatch = i;
         mindist = dist;
      }
   }

   /* Return result. */
   subColor.red   = ctable[bestmatch].red;
   subColor.green = ctable[bestmatch].green;
   subColor.blue  = ctable[bestmatch].blue;
   /* Try to allocate the closest match color.  This should only
    * fail if the cell is read/write.  Otherwise, we're incrementing
    * the cell's reference count.
    */
#ifdef XFree86Server
   if (AllocColor(cmap,
		  &subColor.red, &subColor.green, &subColor.blue,
		  &subColor.pixel,
		  client) == Success) {
#else
   if (XAllocColor(dpy, cmap, &subColor)) {
#endif
      *alloced = 1;
   }
   else {
      /* do this to work around a problem reported by Frank Ortega */
      subColor.pixel = (unsigned long) bestmatch;
      subColor.red   = ctable[bestmatch].red;
      subColor.green = ctable[bestmatch].green;
      subColor.blue  = ctable[bestmatch].blue;
      subColor.flags = DoRed | DoGreen | DoBlue;
      *alloced = 0;
   }
#ifdef XFree86Server
   _mesa_free(ppixIn);
   _mesa_free(ctable);
#else
   /* don't free table, save it for next time */