Merge branch 'nxagent'

1 files changed, 1712 insertions, 0 deletions

diff --git a/nx-X11/programs/Xserver/hw/nxagent/GC.c b/nx-X11/programs/Xserver/hw/nxagent/GC.c
new file mode 100644
index 000000000..71562d999
--- /dev/null
+++ b/nx-X11/programs/Xserver/hw/nxagent/GC.c
@@ -0,0 +1,1712 @@
+/**************************************************************************/
+/*                                                                        */
+/* Copyright (c) 2001, 2011 NoMachine, http://www.nomachine.com/.         */
+/*                                                                        */
+/* NXAGENT, NX protocol compression and NX extensions to this software    */
+/* are copyright of NoMachine. Redistribution and use of the present      */
+/* software is allowed according to terms specified in the file LICENSE   */
+/* which comes in the source distribution.                                */
+/*                                                                        */
+/* Check http://www.nomachine.com/licensing.html for applicability.       */
+/*                                                                        */
+/* NX and NoMachine are trademarks of Medialogic S.p.A.                   */
+/*                                                                        */
+/* All rights reserved.                                                   */
+/*                                                                        */
+/**************************************************************************/
+
+/*
+
+Copyright 1993 by Davor Matic
+
+Permission to use, copy, modify, distribute, and sell this software
+and its documentation for any purpose is hereby granted without fee,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation.  Davor Matic makes no representations about
+the suitability of this software for any purpose.  It is provided "as
+is" without express or implied warranty.
+
+*/
+
+#include "X.h"
+#include "Xproto.h"
+#include "gcstruct.h"
+#include "windowstr.h"
+#include "pixmapstr.h"
+#include "scrnintstr.h"
+#include "dixstruct.h"
+#include "fontstruct.h"
+#include "mistruct.h"
+#include "region.h"
+
+#include "Agent.h"
+
+#include "Display.h"
+#include "GCs.h"
+#include "GCOps.h"
+#include "Image.h"
+#include "Drawable.h"
+#include "Pixmaps.h"
+#include "Font.h"
+#include "Colormap.h"
+#include "Trap.h"
+#include "Screen.h"
+#include "Pixels.h"
+
+#include "../../fb/fb.h"
+
+RESTYPE RT_NX_GC;
+/*
+ * Set here the required log level.
+ */
+
+#define PANIC
+#define WARNING
+#undef  TEST
+#undef  DEBUG
+
+int nxagentGCPrivateIndex;
+
+nxagentGraphicContextsPtr nxagentGraphicContexts;
+int nxagentGraphicContextsSize;
+
+void nxagentDisconnectGraphicContexts(void);
+GCPtr nxagentCreateGraphicContext(int depth);
+
+static void nxagentReconnectGC(void*, XID, void*);
+static void nxagentReconnectClip(GCPtr, int, pointer, int);
+static int  nxagentCompareRegions(RegionPtr, RegionPtr);
+
+struct nxagentGCRec
+{
+  GCPtr pGC;
+  XlibGC gc;
+  struct nxagentGCRec *next;
+};
+
+static struct
+{
+  struct nxagentGCRec *first;
+  struct nxagentGCRec *last;
+  int size;
+} nxagentGCList = { NULL, NULL, 0 };
+
+static struct nxagentGCRec *nxagentGetFirstGC(void);
+
+static void nxagentRestoreGCList(void);
+
+static GCFuncs nxagentFuncs =
+{
+  nxagentValidateGC,
+  nxagentChangeGC,
+  nxagentCopyGC,
+  nxagentDestroyGC,
+  nxagentChangeClip,
+  nxagentDestroyClip,
+  nxagentCopyClip,
+};
+
+static GCOps nxagentOps =
+{
+  nxagentFillSpans,
+  nxagentSetSpans,
+  nxagentPutImage,
+  nxagentCopyArea,
+  nxagentCopyPlane,
+  nxagentPolyPoint,
+  nxagentPolyLines,
+  nxagentPolySegment,
+  nxagentPolyRectangle,
+  nxagentPolyArc,
+  nxagentFillPolygon,
+  nxagentPolyFillRect,
+  nxagentPolyFillArc,
+  nxagentPolyText8,
+  nxagentPolyText16,
+  nxagentImageText8,
+  nxagentImageText16,
+  nxagentImageGlyphBlt,
+  nxagentPolyGlyphBlt,
+  nxagentPushPixels
+};
+
+Bool nxagentCreateGC(GCPtr pGC)
+{
+  FbGCPrivPtr pPriv;
+
+  pGC->clientClipType = CT_NONE;
+  pGC->clientClip = NULL;
+
+  pGC->funcs = &nxagentFuncs;
+  pGC->ops = &nxagentOps;
+
+  pGC->miTranslate = 1;
+
+  if (pGC -> stipple && !nxagentPixmapIsVirtual(pGC -> stipple))
+  {
+    #ifdef DEBUG
+    fprintf(stderr, "nxagentCreateGC: GC at [%p] got real stipple at [%p] switched to virtual.\n",
+                (void*)pGC, (void*)pGC -> stipple);
+    #endif
+
+    pGC -> stipple = nxagentVirtualPixmap(pGC -> stipple);
+  }
+
+  /*
+   * We create the GC based on the default
+   * drawables. The proxy knows this and
+   * optimizes the encoding of the create
+   * GC message to include the id of the
+   * drawable in the checksum.
+   */
+
+  nxagentGCPriv(pGC)->gc = XCreateGC(nxagentDisplay,
+                                     nxagentDefaultDrawables[pGC->depth],
+                                     0L, NULL);
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentCreateGC: GC [%p]\n", (void *) pGC);
+  #endif
+
+  pPriv = (pGC)->devPrivates[fbGCPrivateIndex].ptr;
+
+  fbGetRotatedPixmap(pGC) = 0;
+  fbGetExpose(pGC) = 1;
+  fbGetFreeCompClip(pGC) = 0;
+  fbGetCompositeClip(pGC) = 0;
+
+  pPriv->bpp = BitsPerPixel (pGC->depth);
+
+  nxagentGCPriv(pGC)->nClipRects = 0;
+
+  memset(&(nxagentGCPriv(pGC) -> lastServerValues), 0, sizeof(XGCValues));
+
+  /*
+   * Init to default GC values.
+   */
+
+  nxagentGCPriv(pGC) -> lastServerValues.background = 1;
+
+  nxagentGCPriv(pGC) -> lastServerValues.plane_mask = ~0;
+
+  nxagentGCPriv(pGC) -> lastServerValues.graphics_exposures = 1;
+
+  nxagentGCPriv(pGC) -> lastServerValues.dashes = 4;
+
+  nxagentGCPriv(pGC) -> mid = FakeClientID(serverClient -> index);
+
+  nxagentGCPriv(pGC) -> pPixmap = NULL;
+
+  AddResource(nxagentGCPriv(pGC) -> mid, RT_NX_GC, (pointer) pGC);
+
+  return True;
+}
+
+void nxagentValidateGC(GCPtr pGC, unsigned long changes, DrawablePtr pDrawable)
+{
+  PixmapPtr lastTile, lastStipple;
+
+  DrawablePtr pVirtual = (pDrawable -> type == DRAWABLE_PIXMAP) ?
+                          nxagentVirtualDrawable(pDrawable) :
+                          pDrawable;
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentValidateGC: Going to validate GC at [%p] for drawable at [%p] with changes [%lx].\n",
+              (void *) pGC, (void *) pDrawable, changes);
+  #endif
+
+  pGC->lastWinOrg.x = pDrawable->x;
+  pGC->lastWinOrg.y = pDrawable->y;
+
+  if (!pGC -> tileIsPixel && !nxagentPixmapIsVirtual(pGC -> tile.pixmap))
+  {
+    pGC -> tile.pixmap = nxagentVirtualPixmap(pGC -> tile.pixmap); 
+  }
+
+  lastTile = pGC -> tile.pixmap;
+
+  lastStipple = pGC->stipple;
+  
+  if (lastStipple)
+  {
+    pGC->stipple = nxagentVirtualPixmap(pGC->stipple);
+  }
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentValidateGC: Drawable at [%p] has type [%s] virtual [%p] bits per pixel [%d].\n",
+              (void *) pDrawable, (pDrawable -> type == DRAWABLE_PIXMAP) ? "PIXMAP" : "WINDOW",
+                  (void *) pVirtual, pVirtual -> bitsPerPixel);
+  #endif
+
+  if (pVirtual -> bitsPerPixel == 0)
+  {
+    /*
+     * Don't enter fbValidateGC() with 0 bpp
+     * or agent will block in a endless loop.
+     */
+
+    #ifdef WARNING
+    fprintf(stderr, "nxagentValidateGC: WARNING! Virtual drawable at [%p] has invalid bits per pixel.\n",
+                (void *) pVirtual);
+
+    fprintf(stderr, "nxagentValidateGC: WARNING! While validating GC at [%p] for drawable at [%p] with changes [%lx].\n",
+                (void *) pGC, (void *) pDrawable, changes);
+
+    fprintf(stderr, "nxagentValidateGC: WARNING! Bad drawable at [%p] has type [%s] virtual [%p] bits per pixel [%d].\n",
+                (void *) pDrawable, (pDrawable -> type == DRAWABLE_PIXMAP) ? "PIXMAP" : "WINDOW",
+                    (void *) pVirtual, pVirtual -> bitsPerPixel);
+    #endif
+  }
+  else
+  {
+    fbValidateGC(pGC, changes, pVirtual);
+  }
+
+  if (pGC->tile.pixmap != lastTile)
+  {
+    #ifdef WARNING
+    fprintf(stderr, "nxagentValidateGC: WARNING! Transforming pixmap at [%p] virtual at [%p] "
+                "in virtual pixmap.\n", (void *) nxagentPixmapPriv(pGC -> tile.pixmap) -> pRealPixmap,
+                    (void *) nxagentPixmapPriv(pGC -> tile.pixmap) -> pRealPixmap);
+    #endif
+
+    #ifdef TEST
+    fprintf(stderr, "nxagentValidateGC: GC [%p] new tile [%p] from fb set as virtual\n",
+                (void *) pGC, (void *) pGC->tile.pixmap);
+    #endif
+
+    nxagentPixmapIsVirtual(pGC->tile.pixmap) = True;
+    nxagentRealPixmap(pGC->tile.pixmap) = nxagentRealPixmap(lastTile);
+
+    if (nxagentRealPixmap(lastTile))
+    {
+      nxagentPixmapPriv(nxagentRealPixmap(lastTile))->pVirtualPixmap = pGC->tile.pixmap;
+    }
+  }
+
+  pGC->stipple = lastStipple;
+}
+
+void nxagentChangeGC(GCPtr pGC, unsigned long mask)
+{
+  #ifdef TEST
+  static int nDiscarded;
+  #endif
+
+  XGCValues values;
+
+  int changeFlag = 0;
+
+  if (mask & GCFunction)
+  {
+    values.function = pGC->alu;
+
+    changeFlag |= nxagentTestGC(values.function, function);
+  }
+
+  if (mask & GCPlaneMask)
+  {
+    values.plane_mask = pGC->planemask;
+
+    changeFlag += nxagentTestGC(values.plane_mask, plane_mask);
+  }
+
+  if (mask & GCForeground)
+  {
+    values.foreground = nxagentPixel(pGC->fgPixel);
+
+    changeFlag += nxagentTestGC(values.foreground, foreground);
+  }
+
+  if (mask & GCBackground)
+  {
+    values.background = nxagentPixel(pGC->bgPixel);
+
+    changeFlag += nxagentTestGC(values.background, background);
+  }
+
+  if (mask & GCLineWidth)
+  {
+    values.line_width = pGC->lineWidth;
+
+    changeFlag += nxagentTestGC(values.line_width, line_width);
+  }
+
+  if (mask & GCLineStyle)
+  {
+    values.line_style = pGC->lineStyle;
+
+    changeFlag += nxagentTestGC(values.line_style, line_style);
+  }
+
+  if (mask & GCCapStyle)
+  {
+    values.cap_style = pGC->capStyle;
+
+    changeFlag += nxagentTestGC(values.cap_style, cap_style);
+  }
+
+  if (mask & GCJoinStyle)
+  {
+    values.join_style = pGC->joinStyle;
+
+    changeFlag += nxagentTestGC(values.join_style, join_style);
+  }
+
+  if (mask & GCFillStyle)
+  {
+    values.fill_style = pGC->fillStyle;
+
+    changeFlag += nxagentTestGC(values.fill_style, fill_style);
+  }
+
+  if (mask & GCFillRule)
+  {
+    values.fill_rule = pGC->fillRule;
+
+    changeFlag += nxagentTestGC(values.fill_rule, fill_rule);
+  }
+
+  if (mask & GCTile)
+  {
+    if (pGC->tileIsPixel)
+    {
+      mask &= ~GCTile;
+    }
+    else
+    {
+      if (nxagentDrawableStatus((DrawablePtr) pGC -> tile.pixmap) == NotSynchronized &&
+              nxagentGCTrap == 0)
+      {
+        /*
+         * If the tile is corrupted and is not too
+         * much large, it can be synchronized imme-
+         * diately. In the other cases, the tile is
+         * cleared with a solid color to become usa-
+         * ble. This approach should solve the high
+         * delay on slow links waiting for a back-
+         * ground tile to be synchronized.
+         */
+
+        if (nxagentOption(DeferLevel) >= 2 &&
+               (pGC -> tile.pixmap -> drawable.width > 240 ||
+                    pGC -> tile.pixmap -> drawable.height > 240))
+        {
+          #ifdef TEST
+          fprintf(stderr, "nxagentChangeGC: WARNING! Going to fill with solid color the corrupted tile at [%p] "
+                      "for GC at [%p] with size [%dx%d].\n", (void *) pGC -> tile.pixmap, (void *)pGC,
+                          ((DrawablePtr) pGC -> tile.pixmap) -> width, ((DrawablePtr) pGC -> tile.pixmap) -> height);
+          #endif
+
+          nxagentFillRemoteRegion((DrawablePtr) pGC -> tile.pixmap, nxagentCorruptedRegion((DrawablePtr) pGC -> tile.pixmap));
+        }
+        else
+        {
+          #ifdef TEST
+          fprintf(stderr, "nxagentChangeGC: WARNING! Synchronizing GC at [%p] due the tile at [%p] with size [%dx%d].\n",
+                      (void *)pGC, (void *)pGC -> tile.pixmap, ((DrawablePtr) pGC -> tile.pixmap) -> width,
+                          ((DrawablePtr) pGC -> tile.pixmap) -> height);
+          #endif
+
+          nxagentSynchronizeDrawable((DrawablePtr) pGC -> tile.pixmap, DO_WAIT, NEVER_BREAK, NULL);
+        }
+      }
+
+      values.tile = nxagentPixmap(pGC->tile.pixmap);
+
+      pGC->tile.pixmap = nxagentVirtualPixmap(pGC->tile.pixmap);
+
+      #ifdef TEST
+      fprintf(stderr, "nxagentChangeGC: New tile on GC [%p] tile is [%p]\n",
+                  (void *) pGC, (void *) pGC->tile.pixmap);
+      #endif
+
+      changeFlag += nxagentTestGC(values.tile, tile);
+    }
+  }
+
+  if (mask & GCStipple)
+  {
+    if (nxagentDrawableStatus((DrawablePtr) pGC -> stipple) == NotSynchronized &&
+            nxagentGCTrap == 0)
+    {
+      #ifdef TEST
+      fprintf(stderr, "nxagentChangeGC: WARNING! Synchronizing GC at [%p] due the stipple at [%p].\n",
+                  (void *)pGC, (void *)pGC -> stipple);
+      #endif
+
+      nxagentSynchronizeDrawable((DrawablePtr) pGC -> stipple, DO_WAIT, NEVER_BREAK, NULL);
+    }
+
+    values.stipple = nxagentPixmap(pGC->stipple);
+
+    pGC->stipple = nxagentVirtualPixmap(pGC->stipple);
+
+    #ifdef TEST
+    fprintf(stderr, "nxagentChangeGC: New stipple on GC [%p] stipple is [%p]\n",
+                (void *) pGC, (void *) pGC->stipple);
+    #endif
+
+    changeFlag += nxagentTestGC(values.stipple, stipple);
+  }
+
+  if (mask & GCTileStipXOrigin)
+  {
+    values.ts_x_origin = pGC->patOrg.x;
+
+    changeFlag += nxagentTestGC(values.ts_x_origin, ts_x_origin);
+  }
+
+  if (mask & GCTileStipYOrigin)
+  {
+    values.ts_y_origin = pGC->patOrg.y;
+
+    changeFlag += nxagentTestGC(values.ts_y_origin, ts_y_origin);
+  }
+
+  if (mask & GCFont)
+  {
+    if (!nxagentFontStruct(pGC -> font))
+    {
+      mask &= ~GCFont;
+    }
+    else
+    {
+      values.font = nxagentFont(pGC->font);
+
+      changeFlag += nxagentTestGC(values.font, font);
+    }
+  } 
+
+  if (mask & GCSubwindowMode)
+  {
+    values.subwindow_mode = pGC->subWindowMode;
+
+    changeFlag += nxagentTestGC(values.subwindow_mode, subwindow_mode);
+  }
+
+  if (mask & GCGraphicsExposures)
+  {
+    values.graphics_exposures = pGC->graphicsExposures;
+
+    changeFlag += nxagentTestGC(values.graphics_exposures, graphics_exposures);
+  }
+
+  if (mask & GCClipXOrigin)
+  {
+    values.clip_x_origin = pGC->clipOrg.x;
+
+    changeFlag += nxagentTestGC(values.clip_x_origin, clip_x_origin);
+  }
+
+  if (mask & GCClipYOrigin)
+  {
+    values.clip_y_origin = pGC->clipOrg.y;
+
+    changeFlag += nxagentTestGC(values.clip_y_origin, clip_y_origin);
+  }
+
+  if (mask & GCClipMask)
+  {
+    /*
+     * This is handled in the change clip.
+     */
+
+    mask &= ~GCClipMask;
+  }
+
+  if (mask & GCDashOffset)
+  {
+    values.dash_offset = pGC->dashOffset;
+
+    changeFlag += nxagentTestGC(values.dash_offset, dash_offset);
+  }
+
+  if (mask & GCDashList)
+  {
+    mask &= ~GCDashList;
+
+    if (nxagentGCTrap == 0)
+    {
+      XSetDashes(nxagentDisplay, nxagentGC(pGC),
+                     pGC->dashOffset, (char *)pGC->dash, pGC->numInDashList);
+    }
+  }
+
+  if (mask & GCArcMode)
+  {
+    values.arc_mode = pGC->arcMode;
+
+    changeFlag += nxagentTestGC(values.arc_mode, arc_mode);
+  }
+
+  if (nxagentGCTrap == 1)
+  {
+    #ifdef TEST
+    fprintf(stderr, "nxagentChangeGC: Skipping change of GC at [%p] on the real X server.\n",
+                (void *) pGC);
+    #endif
+
+    return;
+  }
+
+  if (mask && changeFlag)
+  {
+    XChangeGC(nxagentDisplay, nxagentGC(pGC), mask, &values);
+  }
+  #ifdef TEST
+  else if (mask)
+  {
+    fprintf(stderr, "nxagentChangeGC: Discarded [%d] Mask [%lu]\n", ++nDiscarded, mask);
+  }
+  #endif
+}
+
+void nxagentCopyGC(GCPtr pGCSrc, unsigned long mask, GCPtr pGCDst)
+{
+  #ifdef TEST
+  fprintf(stderr, "nxagentCopyGC: Copying the GC with source at [%p] destination "
+              "at [%p] mask [%lu].\n", pGCSrc, pGCDst, mask);
+  #endif
+
+  /*
+   * The MI function doesn't do anything.
+   *
+   * miCopyGC(pGCSrc, mask, pGCDst);
+   */
+
+  XCopyGC(nxagentDisplay, nxagentGC(pGCSrc), mask, nxagentGC(pGCDst));
+
+  /*
+   * Copy the private foreground field
+   * of the GC if GCForeground is set.
+   */
+
+  nxagentCopyGCPriv(GCForeground,foreground,pGCSrc,mask,pGCDst);
+}
+
+void nxagentDestroyGC(GCPtr pGC)
+{
+  #ifdef TEST
+  fprintf(stderr, "nxagentDestroyGC: GC at [%p].\n", (void *) pGC);
+  #endif
+
+  if (nxagentGCPriv(pGC) -> mid != 0)
+  {
+    FreeResource(nxagentGCPriv(pGC) -> mid, RT_NONE);
+  }
+
+  XFreeGC(nxagentDisplay, nxagentGC(pGC));
+
+  miDestroyGC(pGC);
+}
+
+void nxagentChangeClip(GCPtr pGC, int type, pointer pValue, int nRects)
+{
+  int i, size;
+  BoxPtr pBox;
+  XRectangle *pRects;
+  int clipsMatch = 0;
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentChangeClip: Going to change clip on GC [%p]\n",
+              (void *) pGC);
+  #endif
+
+  switch (type)
+  {
+    case CT_NONE:
+    {
+      clipsMatch = (pGC -> clientClipType == None);
+
+      break;
+    }
+    case CT_REGION:
+    {
+      clipsMatch = nxagentCompareRegions(pGC -> clientClip, (RegionPtr) pValue);
+
+      break;
+    }
+    case CT_UNSORTED:
+    case CT_YSORTED:
+    case CT_YXSORTED:
+    case CT_YXBANDED:
+    {
+      RegionPtr pReg = RECTS_TO_REGION(pGC->pScreen, nRects, (xRectangle *)pValue, type);
+
+      clipsMatch = nxagentCompareRegions(pGC -> clientClip, pReg);
+
+      REGION_DESTROY(pGC->pScreen, pReg);
+
+      break;
+    }
+    default:
+    {
+      clipsMatch = 0;
+
+      break;
+    }
+  }
+
+  nxagentDestroyClipHelper(pGC);
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentChangeClip: Type [%d] regions clipsMatch [%d].\n",
+              type, clipsMatch);
+  #endif
+
+  switch (type)
+  {
+    case CT_NONE:
+    {
+      if (clipsMatch == 0 && nxagentGCTrap == 0)
+      {
+        XSetClipMask(nxagentDisplay, nxagentGC(pGC), None);
+      }
+
+      break;
+    }
+    case CT_REGION:
+    {
+      if (clipsMatch == 0 && nxagentGCTrap == 0)
+      {
+        nRects = REGION_NUM_RECTS((RegionPtr)pValue);
+        size = nRects * sizeof(*pRects);
+        pRects = (XRectangle *) xalloc(size);
+        pBox = REGION_RECTS((RegionPtr)pValue);
+
+        for (i = nRects; i-- > 0;)
+        {
+          pRects[i].x = pBox[i].x1;
+          pRects[i].y = pBox[i].y1;
+          pRects[i].width = pBox[i].x2 - pBox[i].x1;
+          pRects[i].height = pBox[i].y2 - pBox[i].y1;
+        }
+
+        XSetClipRectangles(nxagentDisplay, nxagentGC(pGC), pGC -> clipOrg.x, pGC -> clipOrg.y,
+                               pRects, nRects, Unsorted);
+        xfree((char *) pRects);
+      }
+
+      break;
+    }
+    case CT_PIXMAP:
+    {
+      if (nxagentGCTrap == 0)
+      {
+        XSetClipMask(nxagentDisplay, nxagentGC(pGC),
+                         nxagentPixmap((PixmapPtr)pValue));
+      }
+
+      pGC->clientClip = (pointer) (*pGC->pScreen->BitmapToRegion)((PixmapPtr) pValue);
+
+      nxagentGCPriv(pGC)->pPixmap = (PixmapPtr)pValue;
+
+      pValue = pGC->clientClip;
+
+      type = CT_REGION;
+
+      break;
+    }
+    case CT_UNSORTED:
+    {
+      if (clipsMatch == 0 && nxagentGCTrap == 0)
+      {    
+        XSetClipRectangles(nxagentDisplay, nxagentGC(pGC),
+                               pGC->clipOrg.x, pGC->clipOrg.y,
+                                   (XRectangle *)pValue, nRects, Unsorted);
+      }
+
+      break;
+    }
+    case CT_YSORTED:
+    {
+      if (clipsMatch == 0 && nxagentGCTrap == 0)
+      {
+        XSetClipRectangles(nxagentDisplay, nxagentGC(pGC),
+                           pGC->clipOrg.x, pGC->clipOrg.y,
+                           (XRectangle *)pValue, nRects, YSorted);
+      }
+
+      break;
+    }
+    case CT_YXSORTED:
+    {
+      if (clipsMatch == 0 && nxagentGCTrap == 0)
+      {
+        XSetClipRectangles(nxagentDisplay, nxagentGC(pGC),
+                           pGC->clipOrg.x, pGC->clipOrg.y,
+                           (XRectangle *)pValue, nRects, YXSorted);
+      }
+
+      break;
+    }
+    case CT_YXBANDED:
+    {
+      if (clipsMatch == 0 && nxagentGCTrap == 0)
+      {
+        XSetClipRectangles(nxagentDisplay, nxagentGC(pGC),
+                         pGC->clipOrg.x, pGC->clipOrg.y,
+                         (XRectangle *)pValue, nRects, YXBanded);
+      }
+
+      break;
+    }
+  }
+
+  switch(type)
+  {
+    case CT_UNSORTED:
+    case CT_YSORTED:
+    case CT_YXSORTED:
+    case CT_YXBANDED:
+    {
+      /*
+       * Other parts of the server can only
+       * deal with CT_NONE, CT_PIXMAP and
+       * CT_REGION client clips.
+       */
+
+      pGC->clientClip = (pointer) RECTS_TO_REGION(pGC->pScreen, nRects,
+                                                  (xRectangle *)pValue, type);
+      xfree(pValue);
+
+      pValue = pGC->clientClip;
+
+      type = CT_REGION;
+
+      break;
+    }
+    default:
+    {
+      break;
+    }
+  }
+
+  pGC->clientClipType = type;
+  pGC->clientClip = pValue;
+
+  nxagentGCPriv(pGC)->nClipRects = nRects;
+}
+
+void nxagentDestroyClip(GCPtr pGC)
+{
+  miDestroyClip(pGC);
+
+  if (pGC->clientClipType == CT_PIXMAP)
+  {
+    (*pGC->pScreen->DestroyPixmap)((PixmapPtr) (pGC->clientClip));
+  }
+
+  nxagentDestroyClipHelper(pGC);
+
+  if (nxagentGCTrap == 0)
+  {
+    XSetClipMask(nxagentDisplay, nxagentGC(pGC), None);
+  }
+
+  pGC->clientClipType = CT_NONE;
+  pGC->clientClip = NULL;
+
+  nxagentGCPriv(pGC)->nClipRects = 0;
+}
+
+void nxagentDestroyClipHelper(GCPtr pGC)
+{
+  switch (pGC->clientClipType)
+  {
+    default:
+    case CT_NONE:
+      break;
+    case CT_REGION:
+      REGION_DESTROY(pGC->pScreen, pGC->clientClip);
+      break;
+    case CT_PIXMAP:
+      nxagentDestroyPixmap((PixmapPtr)pGC->clientClip);
+      break;
+  }
+
+  if (nxagentGCPriv(pGC)->pPixmap != NULL)
+  {
+    nxagentDestroyPixmap(nxagentGCPriv(pGC)->pPixmap);
+    nxagentGCPriv(pGC)->pPixmap = NULL;
+  }
+}
+
+void nxagentCopyClip(GCPtr pGCDst, GCPtr pGCSrc)
+{
+  RegionPtr pRgn;
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentCopyClip: Going to copy clip from GC [%p] to GC [%p]\n",
+              (void *) pGCDst, (void *) pGCSrc);
+  #endif
+
+  switch (pGCSrc->clientClipType)
+  {
+    case CT_REGION:
+      if (nxagentGCPriv(pGCSrc)->pPixmap == NULL)
+      {
+        pRgn = REGION_CREATE(pGCDst->pScreen, NULL, 1);
+        REGION_COPY(pGCDst->pScreen, pRgn, pGCSrc->clientClip);
+        nxagentChangeClip(pGCDst, CT_REGION, pRgn, 0);
+      }
+      else
+      {
+        nxagentGCPriv(pGCSrc)->pPixmap->refcnt++;
+
+        nxagentChangeClip(pGCDst, CT_PIXMAP, nxagentGCPriv(pGCSrc)->pPixmap, 0);
+      }
+      break;
+    case CT_PIXMAP:
+
+      #ifdef WARNING
+      fprintf(stderr, "nxagentCopyClip: WARNING! Not incrementing counter for virtual pixmap at [%p].\n",
+                  (void *) nxagentVirtualPixmap((PixmapPtr) pGCSrc->clientClip));
+      #endif
+
+      ((PixmapPtr) pGCSrc->clientClip)->refcnt++;
+
+      nxagentChangeClip(pGCDst, CT_PIXMAP, pGCSrc->clientClip, 0);
+
+      break;
+
+    case CT_NONE:
+      nxagentDestroyClip(pGCDst);
+      break;
+
+  }
+}
+
+static struct nxagentGCRec *nxagentGetFirstGC()
+{
+  struct nxagentGCRec *tmp = nxagentGCList.first;
+
+  if (nxagentGCList.size)
+  {
+    nxagentGCList.first = nxagentGCList.first -> next;
+    nxagentGCList.size--;
+
+    if (nxagentGCList.size == 0)
+    {
+      nxagentGCList.last = NULL;
+    }
+  }
+
+  return tmp;
+}
+
+static void nxagentFreeGCRec(struct nxagentGCRec *t)
+{
+  #ifdef TEST
+  fprintf(stderr, "nxagentFreeGCRec: Freeing record at %p GC freed at %p.\n",
+              (void *) t, (void *) t -> gc);
+  #endif
+
+  xfree(t -> gc);
+
+  free(t);
+}
+
+static void nxagentRestoreGCRec(struct nxagentGCRec *t)
+{
+  #ifdef TEST
+  fprintf(stderr, "nxagentRestoreGCRec: Freeing record at %p GC freed at %p.\n",
+              (void*)t, (void*)t -> gc);
+  #endif
+
+  if (nxagentGC(t -> pGC))
+  {
+    xfree(nxagentGC(t -> pGC));
+  }
+
+  nxagentGC(t -> pGC) = t -> gc;
+
+  free(t);
+}
+
+static void nxagentAddGCToList(GCPtr pGC)
+{
+  struct nxagentGCRec *tempGC = malloc(sizeof(struct nxagentGCRec));
+
+  if (tempGC == NULL)
+  {
+    FatalError("nxagentAddGCToList: malloc failed.");
+  }
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentAddGCToList: Adding GC %p to list at memory %p list size is %d.\n",
+              (void *) pGC, (void *) tempGC, nxagentGCList.size);
+  #endif
+
+  tempGC -> pGC = pGC;
+  tempGC -> gc = nxagentGC(pGC);
+  tempGC -> next = NULL;
+
+  if (nxagentGCList.size == 0 || nxagentGCList.first == NULL || nxagentGCList.last == NULL)
+  {
+    nxagentGCList.first = tempGC;
+  }
+  else
+  {
+    nxagentGCList.last -> next = tempGC;
+  }
+
+  nxagentGCList.last = tempGC;
+  nxagentGCList.size++;
+}
+
+void nxagentFreeGCList()
+{
+  struct nxagentGCRec *tempGC;
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentFreeGCList: List size is %d first elt at %p last elt at %p.\n",
+              nxagentGCList.size, (void*)nxagentGCList.first, (void*)nxagentGCList.last);
+  #endif
+
+  while ((tempGC = nxagentGetFirstGC()))
+  {
+    nxagentFreeGCRec(tempGC);
+  }
+}
+
+static void nxagentRestoreGCList()
+{
+  struct nxagentGCRec *tempGC;
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentRestoreGCList: List size is %d first elt at %p last elt at %p.\n",
+              nxagentGCList.size, (void*)nxagentGCList.first, (void*)nxagentGCList.last);
+  #endif
+
+  while ((tempGC = nxagentGetFirstGC()))
+  {
+    nxagentRestoreGCRec(tempGC);
+  }
+}
+
+int nxagentDestroyNewGCResourceType(pointer p, XID id)
+{
+  /*
+   * Address of the destructor is set in Init.c.
+   */
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentDestroyNewGCResourceType: Destroying mirror id [%ld] for GC at [%p].\n",
+              nxagentGCPriv((GCPtr) p) -> mid, (void *) p);
+  #endif
+
+  nxagentGCPriv((GCPtr) p) -> mid = None;
+
+  return 1;
+}
+
+static void nxagentReconnectGC(void *param0, XID param1, pointer param2)
+{
+  XGCValues values;
+  unsigned long valuemask;
+  GCPtr pGC = (GCPtr) param0;
+  Bool *pBool = (Bool*)param2;
+
+  if (pGC == NULL || !*pBool)
+  {
+    return;
+  }
+
+  if (nxagentGC(pGC))
+  {
+    nxagentAddGCToList(pGC);
+  }
+  else
+  {
+    #ifdef WARNING
+    fprintf(stderr, "nxagentReconnectGC: GCRec %p doesn't have a valid pointer to GC data.\n", (void*)pGC);
+    #endif
+  }
+
+  #ifdef DEBUG 
+  fprintf(stderr, "nxagentReconnectGC: GC at [%p].\n", (void *) pGC);
+  #endif
+
+  valuemask = 0;
+  memset(&values,0,sizeof(XGCValues));
+  values.function = pGC->alu;
+  valuemask |= GCFunction;
+  values.plane_mask = pGC->planemask;
+  valuemask |= GCPlaneMask;
+  values.foreground = nxagentPixel(pGC->fgPixel);
+  valuemask |= GCForeground;
+  values.background = nxagentPixel(pGC->bgPixel);
+  valuemask |= GCBackground;
+
+  values.line_width = pGC->lineWidth;
+  valuemask |= GCLineWidth;
+  values.line_style = pGC->lineStyle;
+  valuemask |= GCLineStyle;
+  values.cap_style = pGC->capStyle;
+  valuemask |= GCCapStyle;
+  values.join_style = pGC->joinStyle;
+  valuemask |= GCJoinStyle;
+  values.fill_style = pGC->fillStyle;
+  valuemask |= GCFillStyle;
+  values.fill_rule = pGC->fillRule;
+  valuemask |= GCFillRule;
+
+  if (!pGC -> tileIsPixel  && (pGC -> tile.pixmap != NULL))
+  {
+    if (nxagentPixmapIsVirtual(pGC -> tile.pixmap))
+    {
+      values.tile = nxagentPixmap(nxagentRealPixmap(pGC -> tile.pixmap));
+    }
+    else
+    {
+      values.tile = nxagentPixmap(pGC -> tile.pixmap);
+    }
+
+    valuemask |= GCTile;
+  }
+
+  if (pGC->stipple != NULL)
+  {
+    if (nxagentPixmapIsVirtual(pGC -> stipple))
+    {
+      #ifdef TEST
+      fprintf(stderr, "nxagentReconnectGC: Reconnecting virtual stipple [%p] for GC [%p].\n",
+                  (void *) pGC -> stipple, (void *) pGC);
+      #endif
+
+      if (nxagentPixmap(nxagentRealPixmap(pGC -> stipple)) == 0)
+      {
+        nxagentReconnectPixmap(nxagentRealPixmap(pGC -> stipple), 0, pBool);
+      }
+
+      values.stipple = nxagentPixmap(nxagentRealPixmap(pGC -> stipple));
+    }
+    else
+    {
+      #ifdef TEST
+      fprintf(stderr, "nxagentReconnectGC: Reconnecting stipple [%p] for GC [%p].\n",
+                  (void *) pGC -> stipple, (void *) pGC);
+      #endif
+
+      if (nxagentPixmap(pGC -> stipple) == 0)
+      {
+        nxagentReconnectPixmap(pGC -> stipple, 0, pBool);
+      }
+
+      values.stipple = nxagentPixmap(pGC->stipple);
+    }
+    valuemask |= GCStipple;
+  }
+
+  values.ts_x_origin = pGC->patOrg.x;
+  valuemask |= GCTileStipXOrigin;
+  values.ts_y_origin = pGC->patOrg.y;
+  valuemask |= GCTileStipYOrigin;
+
+  if (pGC->font != NULL)
+  {
+    values.font = nxagentFont(pGC->font);
+    valuemask |= GCFont;
+  }
+
+  values.subwindow_mode = pGC->subWindowMode;
+  valuemask |= GCSubwindowMode;
+  values.graphics_exposures = pGC->graphicsExposures;
+  valuemask |= GCGraphicsExposures;
+  values.clip_x_origin = pGC->clipOrg.x;
+  valuemask |= GCClipXOrigin;
+  values.clip_y_origin = pGC->clipOrg.y;
+  valuemask |= GCClipYOrigin;
+  valuemask |= GCClipMask;
+  values.dash_offset = pGC->dashOffset;
+  valuemask |= GCDashOffset;
+
+  if (pGC->dash != NULL)
+  {
+    values.dashes = *pGC->dash;
+    valuemask |= GCDashList;
+  }
+
+  values.arc_mode = pGC->arcMode;
+  valuemask |= GCArcMode;
+
+  if ((nxagentGC(pGC) = XCreateGC(nxagentDisplay,
+                                  nxagentDefaultDrawables[pGC->depth],
+                                  valuemask, &values)) == NULL)
+  {
+    *pBool = False;
+  }
+
+  nxagentReconnectClip(pGC,
+                       pGC -> clientClipType,
+                       pGC -> clientClip, nxagentGCPriv(pGC) -> nClipRects);
+
+  #ifdef DEBUG
+  XSync(nxagentDisplay, 0);
+  #endif
+}
+
+Bool nxagentReconnectAllGCs(void *p0)
+{
+  int flexibility;
+  int cid;
+  Bool GCSuccess = True;
+
+  flexibility = *(int*)p0;
+
+  #ifdef DEBUG
+  fprintf(stderr, "nxagentReconnectAllGCs\n");
+  #endif
+
+  /*
+   * The resource type RT_NX_GC is created on the
+   * server client only, so we can avoid to loop
+   * through all the clients.
+   */
+
+  FindClientResourcesByType(clients[serverClient -> index], RT_NX_GC, nxagentReconnectGC, &GCSuccess);
+
+  for (cid = 0; (cid < MAXCLIENTS) && GCSuccess; cid++)
+  {
+    if (clients[cid])
+    {
+      #ifdef TEST
+      fprintf(stderr, "nxagentReconnectAllGCs: Going to reconnect GC of client [%d].\n", cid);
+      #endif
+
+      FindClientResourcesByType(clients[cid], RT_GC, nxagentReconnectGC, &GCSuccess);
+    }
+  }
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentReconnectAllGCs: GCs reconnection completed.\n");
+  #endif
+
+  return GCSuccess;
+}
+
+void nxagentDisconnectGC(pointer p0, XID x1, pointer p2)
+{
+  GCPtr pGC = (GCPtr) p0;
+  Bool* pBool = (Bool*) p2;
+
+  if (!*pBool || !pGC)
+  {
+    if (!pGC) 
+    {
+      #ifdef WARNING
+      fprintf(stderr, "nxagentDisconnectGC: WARNING! pGC is NULL.\n");
+      #endif
+    }
+
+    return;
+  }
+
+  if (pGC -> stipple)
+  {
+    PixmapPtr pMap = pGC -> stipple;
+
+    nxagentDisconnectPixmap(nxagentRealPixmap(pMap), 0, pBool);
+  }
+} 
+
+Bool nxagentDisconnectAllGCs()
+{
+  int cid;
+  Bool success = True;
+
+  #ifdef DEBUG
+  fprintf(stderr, "nxagentDisconnectAllGCs\n");
+  #endif
+
+  /*
+   * The resource type RT_NX_GC is created on the
+   * server client only, so we can avoid to loop
+   * through all the clients.
+   */
+
+  FindClientResourcesByType(clients[serverClient -> index], RT_NX_GC,
+                                (FindResType) nxagentDisconnectGC, &success);
+
+  for (cid = 0; (cid < MAXCLIENTS) && success; cid++)
+  {
+    if (clients[cid])
+    {
+      #ifdef TEST
+      fprintf(stderr, "nxagentDisconnectAllGCs: Going to disconnect GC of client [%d].\n", cid);
+      #endif
+
+      FindClientResourcesByType(clients[cid], RT_GC,
+                                    (FindResType) nxagentDisconnectGC, &success);
+    }
+  }
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentDisconnectAllGCs: GCs disconnection completed.\n");
+  #endif
+
+  nxagentRestoreGCList();
+
+  nxagentDisconnectGraphicContexts();
+
+  return success;
+}
+
+static void nxagentReconnectClip(GCPtr pGC, int type, pointer pValue, int nRects)
+{
+  int i, size;
+  BoxPtr pBox;
+  XRectangle *pRects;
+
+  #ifdef TEST
+  fprintf(stderr, "nxagentReconnectClip: going to change clip on GC [%p]\n",
+              (void *) pGC);
+  #endif
+
+  #ifdef DEBUG
+  fprintf(stderr, "nxagentReconnectClip: Type is [%s].\n", (type == CT_NONE) ?
+              "CT_NONE" : (type == CT_REGION) ? "CT_REGION" : (type == CT_PIXMAP) ?
+                  "CT_REGION" : "UNKNOWN");
+  #endif
+
+  switch(type)
+    {
+    case CT_NONE:
+      XSetClipMask(nxagentDisplay, nxagentGC(pGC), None);
+      break;
+
+    case CT_REGION:
+      if (nxagentGCPriv(pGC)->pPixmap == NULL)
+      {
+        nRects = REGION_NUM_RECTS((RegionPtr)pValue);
+        size = nRects * sizeof(*pRects);
+        pRects = (XRectangle *) xalloc(size);
+        pBox = REGION_RECTS((RegionPtr)pValue);
+        for (i = nRects; i-- > 0;) {
+          pRects[i].x = pBox[i].x1;
+          pRects[i].y = pBox[i].y1;
+          pRects[i].width = pBox[i].x2 - pBox[i].x1;
+          pRects[i].height = pBox[i].y2 - pBox[i].y1;
+        }
+
+        /*
+         * Originally, the clip origin area were 0,0 
+         * but it didn't work with kedit and family,
+         * because it got the clip mask of the pixmap
+         * all traslated.
+         */
+
+        XSetClipRectangles(nxagentDisplay, nxagentGC(pGC), pGC -> clipOrg.x, pGC -> clipOrg.y,
+                           pRects, nRects, Unsorted);
+        xfree((char *) pRects);
+      }
+      else
+      {
+        XSetClipMask(nxagentDisplay, nxagentGC(pGC),
+                         nxagentPixmap(nxagentGCPriv(pGC)->pPixmap));
+
+        XSetClipOrigin(nxagentDisplay, nxagentGC(pGC), pGC -> clipOrg.x, pGC -> clipOrg.y);
+      }
+
+      break;
+
+    case CT_PIXMAP:
+
+      XSetClipMask(nxagentDisplay, nxagentGC(pGC),
+                       nxagentPixmap((PixmapPtr)pValue));
+
+      XSetClipOrigin(nxagentDisplay, nxagentGC(pGC), pGC -> clipOrg.x, pGC -> clipOrg.y);
+
+      pGC->clientClip = (pointer) (*pGC->pScreen->BitmapToRegion)((PixmapPtr) pValue);
+
+      nxagentGCPriv(pGC)->pPixmap = (PixmapPtr)pValue;
+
+      pValue = pGC->clientClip;
+
+      type = CT_REGION;
+
+      break;
+
+    case CT_UNSORTED:
+      XSetClipRectangles(nxagentDisplay, nxagentGC(pGC),
+                         pGC->clipOrg.x, pGC->clipOrg.y,
+                         (XRectangle *)pValue, nRects, Unsorted);
+      break;
+
+    case CT_YSORTED:
+      XSetClipRectangles(nxagentDisplay, nxagentGC(pGC),
+                         pGC->clipOrg.x, pGC->clipOrg.y,
+                         (XRectangle *)pValue, nRects, YSorted);
+      break;
+
+    case CT_YXSORTED:
+      XSetClipRectangles(nxagentDisplay, nxagentGC(pGC),
+                         pGC->clipOrg.x, pGC->clipOrg.y,
+                         (XRectangle *)pValue, nRects, YXSorted);
+      break;
+
+    case CT_YXBANDED:
+      XSetClipRectangles(nxagentDisplay, nxagentGC(pGC),
+                         pGC->clipOrg.x, pGC->clipOrg.y,
+                         (XRectangle *)pValue, nRects, YXBanded);
+      break;
+    }
+
+  switch(type)
+    {
+    default:
+      break;
+
+    case CT_UNSORTED:
+    case CT_YSORTED:
+    case CT_YXSORTED:
+    case CT_YXBANDED:
+
+      /*
+       * other parts of server can only deal with CT_NONE,
+       * CT_PIXMAP and CT_REGION client clips.
+       */
+
+      pGC->clientClip = (pointer) RECTS_TO_REGION(pGC->pScreen, nRects,
+                                                  (xRectangle *)pValue, type);
+      xfree(pValue);
+      pValue = pGC->clientClip;
+      type = CT_REGION;
+
+      break;
+    }
+
+  pGC->clientClipType = type;
+  pGC->clientClip = pValue;
+
+ nxagentGCPriv(pGC)->nClipRects = nRects;
+}
+
+static int nxagentCompareRegions(RegionPtr r1, RegionPtr r2)
+{
+  int i;
+
+ /*
+  *  It returns 1 if regions are equal, 0 otherwise
+  */
+
+  if (r1 == NULL && r2 == NULL)
+  {
+    return 1;
+  }
+
+  if ((r1 == NULL) || (r2 == NULL))
+  {
+    return 0;
+  }
+
+  if (REGION_NUM_RECTS(r1) !=  REGION_NUM_RECTS(r2))
+  {
+    return 0;
+  }
+  else if (REGION_NUM_RECTS(r1) == 0)
+  {
+    return 1;
+  }
+  else if ((*REGION_EXTENTS(pScreen, r1)).x1 !=  (*REGION_EXTENTS(pScreen, r2)).x1) return 0;
+  else if ((*REGION_EXTENTS(pScreen, r1)).x2 !=  (*REGION_EXTENTS(pScreen, r2)).x2) return 0;
+  else if ((*REGION_EXTENTS(pScreen, r1)).y1 !=  (*REGION_EXTENTS(pScreen, r2)).y1) return 0;
+  else if ((*REGION_EXTENTS(pScreen, r1)).y2 !=  (*REGION_EXTENTS(pScreen, r2)).y2) return 0;
+  else
+  {
+    for (i = 0; i < REGION_NUM_RECTS(r1); i++)
+    {
+      if (REGION_RECTS(r1)[i].x1 !=  REGION_RECTS(r2)[i].x1) return 0;
+      else if (REGION_RECTS(r1)[i].x2 !=  REGION_RECTS(r2)[i].x2) return 0;
+      else if (REGION_RECTS(r1)[i].y1 !=  REGION_RECTS(r2)[i].y1) return 0;
+      else if (REGION_RECTS(r1)[i].y2 !=  REGION_RECTS(r2)[i].y2) return 0;
+    }
+  }
+
+  return 1;
+}
+
+/*
+ * This function have to be called in the place
+ * of GetScratchGC if the GC will be used to per-
+ * form operations also on the remote X Server.
+ * This is why we call the XChangeGC at the end of
+ * the function.
+ */
+GCPtr nxagentGetScratchGC(unsigned depth, ScreenPtr pScreen)
+{
+  GCPtr pGC;
+  XGCValues values;
+  unsigned long mask;
+  int nxagentSaveGCTrap;
+
+  /*
+   * The GC trap is temporarily disabled in
+   * order to allow the remote clipmask reset
+   * requested by GetScratchGC().
+   */
+
+  nxagentSaveGCTrap = nxagentGCTrap;
+
+  nxagentGCTrap = 0;
+
+  pGC = GetScratchGC(depth, pScreen);
+
+  nxagentGCTrap = nxagentSaveGCTrap;
+
+  if (pGC == NULL)
+  {
+    #ifdef WARNING
+    fprintf(stderr, "nxagentGetScratchGC: Failed to retrieve the scratch GC.\n");
+    #endif
+
+    return NULL;
+  }
+
+  mask = 0;
+
+  values.function = pGC -> alu;
+  mask |= GCFunction;
+
+  values.plane_mask = pGC -> planemask;
+  mask |= GCPlaneMask;
+
+  values.foreground = nxagentPixel(pGC -> fgPixel);
+  mask |= GCForeground;
+
+  values.background = nxagentPixel(pGC -> bgPixel);
+  mask |= GCBackground;
+
+  values.line_width = pGC -> lineWidth;
+  mask |= GCLineWidth;
+
+  values.line_style = pGC -> lineStyle;
+  mask |= GCLineStyle;
+
+  values.cap_style = pGC -> capStyle;
+  mask |= GCCapStyle;
+
+  values.join_style = pGC -> joinStyle;
+  mask |= GCJoinStyle;
+
+  values.fill_style = pGC -> fillStyle;
+  mask |= GCFillStyle;
+
+  values.fill_rule = pGC -> fillRule;
+  mask |= GCFillRule;
+
+  values.arc_mode = pGC -> arcMode;
+  mask |= GCArcMode;
+
+  values.ts_x_origin = pGC -> patOrg.x;
+  mask |= GCTileStipXOrigin;
+
+  values.ts_y_origin = pGC -> patOrg.y;
+  mask |= GCTileStipYOrigin;
+
+  values.subwindow_mode = pGC -> subWindowMode;
+  mask |= GCSubwindowMode;
+
+  values.graphics_exposures = pGC -> graphicsExposures;
+  mask |= GCGraphicsExposures;
+
+  /*
+   * The GCClipMask is set to none inside
+   * the GetScratchGC() function.
+   */
+
+  values.clip_x_origin = pGC -> clipOrg.x;
+  mask |= GCClipXOrigin;
+
+  values.clip_y_origin = pGC -> clipOrg.y;
+  mask |= GCClipYOrigin;
+
+  XChangeGC(nxagentDisplay, nxagentGC(pGC), mask, &values);
+
+  memset(&(nxagentGCPriv(pGC) -> lastServerValues), 0, sizeof(XGCValues));
+
+  return pGC;
+}
+
+/*
+ * This function is only a wrapper for
+ * FreeScratchGC.
+ */
+void nxagentFreeScratchGC(GCPtr pGC)
+{
+  if (pGC == NULL)
+  {
+    #ifdef WARNING
+    fprintf(stderr, "nxagentFreeScratchGC: WARNING! pGC is NULL.\n");
+    #endif
+
+    return;
+  }
+
+  FreeScratchGC(pGC);
+}
+
+/*
+ * The GCs belonging to this list are used
+ * only in the synchronization put images,
+ * to be sure they preserve the default va-
+ * lues and to avoid XChangeGC() requests.
+ */
+
+GCPtr nxagentGetGraphicContext(DrawablePtr pDrawable)
+{
+  int i;
+  int result;
+
+  for (i = 0; i < nxagentGraphicContextsSize; i++)
+  {
+    if (pDrawable -> depth == nxagentGraphicContexts[i].depth)
+    {
+      #ifdef DEBUG
+      fprintf(stderr, "nxagentGetGraphicContext: Found a valid GC at [%p] for depth [%d].\n",
+                  (void *) nxagentGraphicContexts[i].pGC, pDrawable -> depth);
+      #endif
+
+      /*
+       * Reconnect the GC if needed.
+       */
+
+      if (nxagentGraphicContexts[i].dirty == 1)
+      {
+        #ifdef DEBUG
+        fprintf(stderr, "nxagentGetGraphicContext: Going to reconnect the GC.\n");
+        #endif
+
+        result = 1;
+
+        nxagentReconnectGC(nxagentGraphicContexts[i].pGC, (XID) 0, &result);
+
+        if (result == 0)
+        {
+          #ifdef WARNING
+          fprintf(stderr, "nxagentGetGraphicContext: WARNING! Failed to reconnect the GC.\n");
+          #endif
+
+          return NULL;
+        }
+
+        nxagentGraphicContexts[i].dirty = 0;
+      }
+
+      return nxagentGraphicContexts[i].pGC;
+    }
+  }
+
+  return nxagentCreateGraphicContext(pDrawable -> depth);
+}
+
+GCPtr nxagentCreateGraphicContext(int depth)
+{
+  GCPtr pGC;
+
+  nxagentGraphicContextsPtr nxagentGCs;
+
+  XID attributes[2];
+
+  /*
+   * We have not found a GC, so we have
+   * to spread the list and add a new GC.
+   */
+
+  nxagentGCs = xrealloc(nxagentGraphicContexts, (nxagentGraphicContextsSize + 1) * sizeof(nxagentGraphicContextsRec));
+   
+  if (nxagentGCs == NULL)
+  {
+    #ifdef WARNING
+    fprintf(stderr, "nxagentCreateGraphicContext: Cannot allocate memory for a GC.\n");
+    #endif
+
+    return NULL;
+  }
+
+  nxagentGraphicContexts = nxagentGCs;
+
+  pGC = CreateScratchGC(nxagentDefaultScreen, depth);
+
+  if (pGC == NULL)
+  {
+    #ifdef WARNING
+    fprintf(stderr, "nxagentCreateGraphicContext: Failed to create a GC for depth [%d].\n",
+                depth);
+    #endif
+
+    return NULL;
+  }
+
+  /*
+   * Color used in nxagentFillRemoteRegion().
+   */
+
+  attributes[0] = 0xc1c1c1;
+
+  if (depth == 15 || depth == 16)
+  {
+    Color32to16(attributes[0]);
+  }
+
+  /*
+   * The IncludeInferiors property is useful to
+   * solve problems when synchronizing windows
+   * covered by an invisible child.
+   */
+
+  attributes[1] = IncludeInferiors;
+
+  ChangeGC(pGC, GCForeground | GCSubwindowMode, attributes);
+
+  nxagentGraphicContexts[nxagentGraphicContextsSize].pGC   = pGC;
+  nxagentGraphicContexts[nxagentGraphicContextsSize].depth = depth;
+  nxagentGraphicContexts[nxagentGraphicContextsSize].dirty = 0;
+
+  nxagentGraphicContextsSize++;
+
+  #ifdef DEBUG
+  fprintf(stderr, "nxagentCreateGraphicContext: GC [%p] for depth [%d] added to the list of size [%d].\n",
+              (void *) pGC, depth, nxagentGraphicContextsSize);
+  #endif
+
+  return pGC;
+}
+
+/*
+ * This initialization is called in the InitOutput()
+ * function immediately after opening the screen,
+ * which is used to create the GCs. 
+ */
+
+void nxagentAllocateGraphicContexts(void)
+{
+  int *depths;
+
+  int i;
+
+  depths = nxagentDepths;
+
+  for (i = 0; i < nxagentNumDepths; i++)
+  {
+    nxagentCreateGraphicContext(*depths);
+
+    depths++;
+  }
+}
+
+void nxagentDisconnectGraphicContexts(void)
+{
+  int i;
+
+  for (i = 0; i < nxagentGraphicContextsSize; i++)
+  {
+    nxagentGraphicContexts[i].dirty = 1;
+  }
+
+  return;
+}
+