/*
 * misprite.c
 *
 * machine independent software sprite routines
 */

/* $Xorg: misprite.c,v 1.4 2001/02/09 02:05:22 xorgcvs Exp $ */

/*

Copyright 1989, 1998  The Open Group

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.

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Except as contained in this notice, the name of The Open Group shall not be
used in advertising or otherwise to promote the sale, use or other dealings
in this Software without prior written authorization from The Open Group.
*/
/* $XFree86$ */

# include   "X.h"
# include   "Xproto.h"
# include   "misc.h"
# include   "pixmapstr.h"
# include   "input.h"
# include   "mi.h"
# include   "cursorstr.h"
# include   "font.h"
# include   "scrnintstr.h"
# include   "colormapst.h"
# include   "windowstr.h"
# include   "gcstruct.h"
# include   "mipointer.h"
# include   "mispritest.h"
# include   "dixfontstr.h"
# include   "fontstruct.h"
#ifdef RENDER
# include   "mipict.h"
#endif

/*
 * screen wrappers
 */

static int  miSpriteScreenIndex;
static unsigned long miSpriteGeneration = 0;

static Bool	    miSpriteCloseScreen(int i, ScreenPtr pScreen);
static void	    miSpriteGetImage(DrawablePtr pDrawable, int sx, int sy,
				     int w, int h, unsigned int format,
				     unsigned long planemask, char *pdstLine);
static void	    miSpriteGetSpans(DrawablePtr pDrawable, int wMax,
				     DDXPointPtr ppt, int *pwidth, int nspans,
				     char *pdstStart);
static void	    miSpriteSourceValidate(DrawablePtr pDrawable, int x, int y,
					   int width, int height);
static Bool	    miSpriteCreateGC(GCPtr pGC);
static void	    miSpriteBlockHandler(int i, pointer blockData,
					 pointer pTimeout,
					 pointer pReadMask);
static void	    miSpriteInstallColormap(ColormapPtr pMap);
static void	    miSpriteStoreColors(ColormapPtr pMap, int ndef,
					xColorItem *pdef);

static void	    miSpritePaintWindowBackground(WindowPtr pWin,
						  RegionPtr pRegion, int what);
static void	    miSpritePaintWindowBorder(WindowPtr pWin,
					      RegionPtr pRegion, int what);
static void	    miSpriteCopyWindow(WindowPtr pWin, DDXPointRec ptOldOrg,
				       RegionPtr pRegion);
static void	    miSpriteClearToBackground(WindowPtr pWin, int x, int y,
					      int w, int h,
					      Bool generateExposures);

#ifdef RENDER
static void	    miSpriteComposite(CARD8	op,
				      PicturePtr pSrc,
				      PicturePtr pMask,
				      PicturePtr pDst,
				      INT16	xSrc,
				      INT16	ySrc,
				      INT16	xMask,
				      INT16	yMask,
				      INT16	xDst,
				      INT16	yDst,
				      CARD16	width,
				      CARD16	height);

static void	    miSpriteGlyphs(CARD8	op,
				   PicturePtr	pSrc,
				   PicturePtr	pDst,
				   PictFormatPtr maskFormat,
				   INT16	xSrc,
				   INT16	ySrc,
				   int		nlist,
				   GlyphListPtr	list,
				   GlyphPtr	*glyphs);
#endif

static void	    miSpriteSaveDoomedAreas(WindowPtr pWin,
					    RegionPtr pObscured, int dx,
					    int dy);
static RegionPtr    miSpriteRestoreAreas(WindowPtr pWin, RegionPtr pRgnExposed);
static void	    miSpriteComputeSaved(ScreenPtr pScreen);

#define SCREEN_PROLOGUE(pScreen, field)\
  ((pScreen)->field = \
   ((miSpriteScreenPtr) (pScreen)->devPrivates[miSpriteScreenIndex].ptr)->field)

#define SCREEN_EPILOGUE(pScreen, field, wrapper)\
    ((pScreen)->field = wrapper)

/*
 * GC func wrappers
 */

static int  miSpriteGCIndex;

static void miSpriteValidateGC(GCPtr pGC, unsigned long stateChanges,
			       DrawablePtr pDrawable);
static void miSpriteCopyGC(GCPtr pGCSrc, unsigned long mask, GCPtr pGCDst);
static void miSpriteDestroyGC(GCPtr pGC);
static void miSpriteChangeGC(GCPtr pGC, unsigned long mask);
static void miSpriteChangeClip(GCPtr pGC, int type, pointer pvalue, int nrects);
static void miSpriteDestroyClip(GCPtr pGC);
static void miSpriteCopyClip(GCPtr pgcDst, GCPtr pgcSrc);

static GCFuncs	miSpriteGCFuncs = {
    miSpriteValidateGC,
    miSpriteChangeGC,
    miSpriteCopyGC,
    miSpriteDestroyGC,
    miSpriteChangeClip,
    miSpriteDestroyClip,
    miSpriteCopyClip,
};

#define GC_FUNC_PROLOGUE(pGC)					\
    miSpriteGCPtr   pGCPriv =					\
	(miSpriteGCPtr) (pGC)->devPrivates[miSpriteGCIndex].ptr;\
    (pGC)->funcs = pGCPriv->wrapFuncs;				\
    if (pGCPriv->wrapOps)					\
	(pGC)->ops = pGCPriv->wrapOps;

#define GC_FUNC_EPILOGUE(pGC)					\
    pGCPriv->wrapFuncs = (pGC)->funcs;				\
    (pGC)->funcs = &miSpriteGCFuncs;				\
    if (pGCPriv->wrapOps)					\
    {								\
	pGCPriv->wrapOps = (pGC)->ops;				\
	(pGC)->ops = &miSpriteGCOps;				\
    }

/*
 * GC op wrappers
 */

static void	    miSpriteFillSpans(DrawablePtr pDrawable, GCPtr pGC,
				      int nInit, DDXPointPtr pptInit,
				      int *pwidthInit, int fSorted);
static void	    miSpriteSetSpans(DrawablePtr pDrawable, GCPtr pGC,
				     char *psrc, DDXPointPtr ppt, int *pwidth,
				     int nspans, int fSorted);
static void	    miSpritePutImage(DrawablePtr pDrawable, GCPtr pGC,
				     int depth, int x, int y, int w, int h,
				     int leftPad, int format, char *pBits);
static RegionPtr    miSpriteCopyArea(DrawablePtr pSrc, DrawablePtr pDst,
				     GCPtr pGC, int srcx, int srcy, int w,
				     int h, int dstx, int dsty);
static RegionPtr    miSpriteCopyPlane(DrawablePtr pSrc, DrawablePtr pDst,
				     GCPtr pGC, int srcx, int srcy, int w,
				     int h, int dstx, int dsty,
				     unsigned long plane);
static void	    miSpritePolyPoint(DrawablePtr pDrawable, GCPtr pGC,
				      int mode, int npt, xPoint *pptInit);
static void	    miSpritePolylines(DrawablePtr pDrawable, GCPtr pGC,
				      int mode, int npt, DDXPointPtr pptInit);
static void	    miSpritePolySegment(DrawablePtr pDrawable, GCPtr pGC,
					int nseg, xSegment *pSegs);
static void	    miSpritePolyRectangle(DrawablePtr pDrawable, GCPtr pGC,
					  int nrects, xRectangle *pRects);
static void	    miSpritePolyArc(DrawablePtr pDrawable, GCPtr pGC,
				    int narcs, xArc *parcs);
static void	    miSpriteFillPolygon(DrawablePtr pDrawable, GCPtr pGC,
					int shape, int mode, int count,
					DDXPointPtr pPts);
static void	    miSpritePolyFillRect(DrawablePtr pDrawable, GCPtr pGC,
					 int nrectFill, xRectangle *prectInit);
static void	    miSpritePolyFillArc(DrawablePtr pDrawable, GCPtr pGC,
					int narcs, xArc *parcs);
static int	    miSpritePolyText8(DrawablePtr pDrawable, GCPtr pGC,
				      int x, int y, int count, char *chars);
static int	    miSpritePolyText16(DrawablePtr pDrawable, GCPtr pGC,
				       int x, int y, int count,
				       unsigned short *chars);
static void	    miSpriteImageText8(DrawablePtr pDrawable, GCPtr pGC,
				       int x, int y, int count, char *chars);
static void	    miSpriteImageText16(DrawablePtr pDrawable, GCPtr pGC,
					int x, int y, int count,
					unsigned short *chars);
static void	    miSpriteImageGlyphBlt(DrawablePtr pDrawable, GCPtr pGC,
					  int x, int y, unsigned int nglyph,
					  CharInfoPtr *ppci,
					  pointer pglyphBase);
static void	    miSpritePolyGlyphBlt(DrawablePtr pDrawable, GCPtr pGC,
					 int x, int y, unsigned int nglyph,
					 CharInfoPtr *ppci,
					 pointer pglyphBase);
static void	    miSpritePushPixels(GCPtr pGC, PixmapPtr pBitMap,
				       DrawablePtr pDst, int w, int h,
				       int x, int y);
#ifdef NEED_LINEHELPER
static void	    miSpriteLineHelper(void);
#endif

static GCOps miSpriteGCOps = {
    miSpriteFillSpans,	    miSpriteSetSpans,	    miSpritePutImage,	
    miSpriteCopyArea,	    miSpriteCopyPlane,	    miSpritePolyPoint,
    miSpritePolylines,	    miSpritePolySegment,    miSpritePolyRectangle,
    miSpritePolyArc,	    miSpriteFillPolygon,    miSpritePolyFillRect,
    miSpritePolyFillArc,    miSpritePolyText8,	    miSpritePolyText16,
    miSpriteImageText8,	    miSpriteImageText16,    miSpriteImageGlyphBlt,
    miSpritePolyGlyphBlt,   miSpritePushPixels
#ifdef NEED_LINEHELPER
    , miSpriteLineHelper
#endif
};

/*
 * testing only -- remove cursor for every draw.  Eventually,
 * each draw operation will perform a bounding box check against
 * the saved cursor area
 */

#define GC_SETUP_CHEAP(pDrawable)				    \
    miSpriteScreenPtr	pScreenPriv = (miSpriteScreenPtr)	    \
	(pDrawable)->pScreen->devPrivates[miSpriteScreenIndex].ptr; \

#define GC_SETUP(pDrawable, pGC)				    \
    GC_SETUP_CHEAP(pDrawable)					    \
    miSpriteGCPtr	pGCPrivate = (miSpriteGCPtr)		    \
	(pGC)->devPrivates[miSpriteGCIndex].ptr;		    \
    GCFuncs *oldFuncs = pGC->funcs;

#define GC_SETUP_AND_CHECK(pDrawable, pGC)			    \
    GC_SETUP(pDrawable, pGC);					    \
    if (GC_CHECK((WindowPtr)pDrawable))				    \
	miSpriteRemoveCursor (pDrawable->pScreen);
    
#define GC_CHECK(pWin)						    \
    (pScreenPriv->isUp &&					    \
        (pScreenPriv->pCacheWin == pWin ?			    \
	    pScreenPriv->isInCacheWin : (			    \
	    (pScreenPriv->pCacheWin = (pWin)),			    \
	    (pScreenPriv->isInCacheWin =			    \
		(pWin)->drawable.x < pScreenPriv->saved.x2 &&	    \
		pScreenPriv->saved.x1 < (pWin)->drawable.x +	    \
				    (int) (pWin)->drawable.width && \
		(pWin)->drawable.y < pScreenPriv->saved.y2 &&	    \
		pScreenPriv->saved.y1 < (pWin)->drawable.y +	    \
				    (int) (pWin)->drawable.height &&\
		RECT_IN_REGION((pWin)->drawable.pScreen, &(pWin)->borderClip, \
			&pScreenPriv->saved) != rgnOUT))))

#define GC_OP_PROLOGUE(pGC) { \
    (pGC)->funcs = pGCPrivate->wrapFuncs; \
    (pGC)->ops = pGCPrivate->wrapOps; \
    }

#define GC_OP_EPILOGUE(pGC) { \
    pGCPrivate->wrapOps = (pGC)->ops; \
    (pGC)->funcs = oldFuncs; \
    (pGC)->ops = &miSpriteGCOps; \
    }

/*
 * pointer-sprite method table
 */

static Bool miSpriteRealizeCursor(ScreenPtr pScreen, CursorPtr pCursor);
static Bool miSpriteUnrealizeCursor(ScreenPtr pScreen, CursorPtr pCursor);
static void miSpriteSetCursor(ScreenPtr pScreen, CursorPtr pCursor,
			      int x, int y);
static void miSpriteMoveCursor(ScreenPtr pScreen, int x, int y);

miPointerSpriteFuncRec miSpritePointerFuncs = {
    miSpriteRealizeCursor,
    miSpriteUnrealizeCursor,
    miSpriteSetCursor,
    miSpriteMoveCursor,
};

/*
 * other misc functions
 */

static void miSpriteRemoveCursor(ScreenPtr pScreen);
static void miSpriteRestoreCursor(ScreenPtr pScreen);

/*
 * miSpriteInitialize -- called from device-dependent screen
 * initialization proc after all of the function pointers have
 * been stored in the screen structure.
 */

Bool
miSpriteInitialize (pScreen, cursorFuncs, screenFuncs)
    ScreenPtr		    pScreen;
    miSpriteCursorFuncPtr   cursorFuncs;
    miPointerScreenFuncPtr  screenFuncs;
{
    miSpriteScreenPtr	pPriv;
    VisualPtr		pVisual;
#ifdef RENDER
    PictureScreenPtr	ps = GetPictureScreenIfSet(pScreen);
#endif
    
    if (miSpriteGeneration != serverGeneration)
    {
	miSpriteScreenIndex = AllocateScreenPrivateIndex ();
	if (miSpriteScreenIndex < 0)
	    return FALSE;
	miSpriteGeneration = serverGeneration;
	miSpriteGCIndex = AllocateGCPrivateIndex ();
    }
    if (!AllocateGCPrivate(pScreen, miSpriteGCIndex, sizeof(miSpriteGCRec)))
	return FALSE;
    pPriv = (miSpriteScreenPtr) xalloc (sizeof (miSpriteScreenRec));
    if (!pPriv)
	return FALSE;
    if (!miPointerInitialize (pScreen, &miSpritePointerFuncs, screenFuncs,TRUE))
    {
	xfree ((pointer) pPriv);
	return FALSE;
    }
    for (pVisual = pScreen->visuals;
	 pVisual->vid != pScreen->rootVisual;
	 pVisual++)
	;
    pPriv->pVisual = pVisual;
    pPriv->CloseScreen = pScreen->CloseScreen;
    pPriv->GetImage = pScreen->GetImage;
    pPriv->GetSpans = pScreen->GetSpans;
    pPriv->SourceValidate = pScreen->SourceValidate;
    pPriv->CreateGC = pScreen->CreateGC;
    pPriv->BlockHandler = pScreen->BlockHandler;
    pPriv->InstallColormap = pScreen->InstallColormap;
    pPriv->StoreColors = pScreen->StoreColors;

    pPriv->PaintWindowBackground = pScreen->PaintWindowBackground;
    pPriv->PaintWindowBorder = pScreen->PaintWindowBorder;
    pPriv->CopyWindow = pScreen->CopyWindow;
    pPriv->ClearToBackground = pScreen->ClearToBackground;

    pPriv->SaveDoomedAreas = pScreen->SaveDoomedAreas;
    pPriv->RestoreAreas = pScreen->RestoreAreas;
#ifdef RENDER
    if (ps)
    {
	pPriv->Composite = ps->Composite;
	pPriv->Glyphs = ps->Glyphs;
    }
#endif
    
    pPriv->pCursor = NULL;
    pPriv->x = 0;
    pPriv->y = 0;
    pPriv->isUp = FALSE;
    pPriv->shouldBeUp = FALSE;
    pPriv->pCacheWin = NullWindow;
    pPriv->isInCacheWin = FALSE;
    pPriv->checkPixels = TRUE;
    pPriv->pInstalledMap = NULL;
    pPriv->pColormap = NULL;
    pPriv->funcs = cursorFuncs;
    pPriv->colors[SOURCE_COLOR].red = 0;
    pPriv->colors[SOURCE_COLOR].green = 0;
    pPriv->colors[SOURCE_COLOR].blue = 0;
    pPriv->colors[MASK_COLOR].red = 0;
    pPriv->colors[MASK_COLOR].green = 0;
    pPriv->colors[MASK_COLOR].blue = 0;
    pScreen->devPrivates[miSpriteScreenIndex].ptr = (pointer) pPriv;
    pScreen->CloseScreen = miSpriteCloseScreen;
    pScreen->GetImage = miSpriteGetImage;
    pScreen->GetSpans = miSpriteGetSpans;
    pScreen->SourceValidate = miSpriteSourceValidate;
    pScreen->CreateGC = miSpriteCreateGC;
    pScreen->BlockHandler = miSpriteBlockHandler;
    pScreen->InstallColormap = miSpriteInstallColormap;
    pScreen->StoreColors = miSpriteStoreColors;

    pScreen->PaintWindowBackground = miSpritePaintWindowBackground;
    pScreen->PaintWindowBorder = miSpritePaintWindowBorder;
    pScreen->CopyWindow = miSpriteCopyWindow;
    pScreen->ClearToBackground = miSpriteClearToBackground;

    pScreen->SaveDoomedAreas = miSpriteSaveDoomedAreas;
    pScreen->RestoreAreas = miSpriteRestoreAreas;
#ifdef RENDER
    if (ps)
    {
	ps->Composite = miSpriteComposite;
	ps->Glyphs = miSpriteGlyphs;
    }
#endif

    return TRUE;
}

/*
 * Screen wrappers
 */

/*
 * CloseScreen wrapper -- unwrap everything, free the private data
 * and call the wrapped function
 */

static Bool
miSpriteCloseScreen (i, pScreen)
    int i;
    ScreenPtr	pScreen;
{
    miSpriteScreenPtr   pScreenPriv;
#ifdef RENDER
    PictureScreenPtr	ps = GetPictureScreenIfSet(pScreen);
#endif

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;

    pScreen->CloseScreen = pScreenPriv->CloseScreen;
    pScreen->GetImage = pScreenPriv->GetImage;
    pScreen->GetSpans = pScreenPriv->GetSpans;
    pScreen->SourceValidate = pScreenPriv->SourceValidate;
    pScreen->CreateGC = pScreenPriv->CreateGC;
    pScreen->BlockHandler = pScreenPriv->BlockHandler;
    pScreen->InstallColormap = pScreenPriv->InstallColormap;
    pScreen->StoreColors = pScreenPriv->StoreColors;

    pScreen->PaintWindowBackground = pScreenPriv->PaintWindowBackground;
    pScreen->PaintWindowBorder = pScreenPriv->PaintWindowBorder;
    pScreen->CopyWindow = pScreenPriv->CopyWindow;
    pScreen->ClearToBackground = pScreenPriv->ClearToBackground;

    pScreen->SaveDoomedAreas = pScreenPriv->SaveDoomedAreas;
    pScreen->RestoreAreas = pScreenPriv->RestoreAreas;
#ifdef RENDER
    if (ps)
    {
	ps->Composite = pScreenPriv->Composite;
	ps->Glyphs = pScreenPriv->Glyphs;
    }
#endif
    xfree ((pointer) pScreenPriv);

    return (*pScreen->CloseScreen) (i, pScreen);
}

static void
miSpriteGetImage (pDrawable, sx, sy, w, h, format, planemask, pdstLine)
    DrawablePtr	    pDrawable;
    int		    sx, sy, w, h;
    unsigned int    format;
    unsigned long   planemask;
    char	    *pdstLine;
{
    ScreenPtr	    pScreen = pDrawable->pScreen;
    miSpriteScreenPtr    pScreenPriv;
    
    SCREEN_PROLOGUE (pScreen, GetImage);

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;

    if (pDrawable->type == DRAWABLE_WINDOW &&
        pScreenPriv->isUp &&
	ORG_OVERLAP(&pScreenPriv->saved,pDrawable->x,pDrawable->y, sx, sy, w, h))
    {
	miSpriteRemoveCursor (pScreen);
    }

    (*pScreen->GetImage) (pDrawable, sx, sy, w, h,
			  format, planemask, pdstLine);

    SCREEN_EPILOGUE (pScreen, GetImage, miSpriteGetImage);
}

static void
miSpriteGetSpans (pDrawable, wMax, ppt, pwidth, nspans, pdstStart)
    DrawablePtr	pDrawable;
    int		wMax;
    DDXPointPtr	ppt;
    int		*pwidth;
    int		nspans;
    char	*pdstStart;
{
    ScreenPtr		    pScreen = pDrawable->pScreen;
    miSpriteScreenPtr	    pScreenPriv;
    
    SCREEN_PROLOGUE (pScreen, GetSpans);

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;

    if (pDrawable->type == DRAWABLE_WINDOW && pScreenPriv->isUp)
    {
	register DDXPointPtr    pts;
	register int    	*widths;
	register int    	nPts;
	register int    	xorg,
				yorg;

	xorg = pDrawable->x;
	yorg = pDrawable->y;

	for (pts = ppt, widths = pwidth, nPts = nspans;
	     nPts--;
	     pts++, widths++)
 	{
	    if (SPN_OVERLAP(&pScreenPriv->saved,pts->y+yorg,
			     pts->x+xorg,*widths))
	    {
		miSpriteRemoveCursor (pScreen);
		break;
	    }
	}
    }

    (*pScreen->GetSpans) (pDrawable, wMax, ppt, pwidth, nspans, pdstStart);

    SCREEN_EPILOGUE (pScreen, GetSpans, miSpriteGetSpans);
}

static void
miSpriteSourceValidate (pDrawable, x, y, width, height)
    DrawablePtr	pDrawable;
    int		x, y, width, height;
{
    ScreenPtr		    pScreen = pDrawable->pScreen;
    miSpriteScreenPtr	    pScreenPriv;
    
    SCREEN_PROLOGUE (pScreen, SourceValidate);

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;

    if (pDrawable->type == DRAWABLE_WINDOW && pScreenPriv->isUp &&
	ORG_OVERLAP(&pScreenPriv->saved, pDrawable->x, pDrawable->y,
		    x, y, width, height))
    {
	miSpriteRemoveCursor (pScreen);
    }

    if (pScreen->SourceValidate)
	(*pScreen->SourceValidate) (pDrawable, x, y, width, height);

    SCREEN_EPILOGUE (pScreen, SourceValidate, miSpriteSourceValidate);
}

static Bool
miSpriteCreateGC (pGC)
    GCPtr   pGC;
{
    ScreenPtr	    pScreen = pGC->pScreen;
    Bool	    ret;
    miSpriteGCPtr   pPriv;

    SCREEN_PROLOGUE (pScreen, CreateGC);
    
    pPriv = (miSpriteGCPtr)pGC->devPrivates[miSpriteGCIndex].ptr;

    ret = (*pScreen->CreateGC) (pGC);

    pPriv->wrapOps = NULL;
    pPriv->wrapFuncs = pGC->funcs;
    pGC->funcs = &miSpriteGCFuncs;

    SCREEN_EPILOGUE (pScreen, CreateGC, miSpriteCreateGC);

    return ret;
}

static void
miSpriteBlockHandler (i, blockData, pTimeout, pReadmask)
    int	i;
    pointer	blockData;
    pointer	pTimeout;
    pointer	pReadmask;
{
    ScreenPtr		pScreen = screenInfo.screens[i];
    miSpriteScreenPtr	pPriv;

    pPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;

    SCREEN_PROLOGUE(pScreen, BlockHandler);
    
    (*pScreen->BlockHandler) (i, blockData, pTimeout, pReadmask);

    SCREEN_EPILOGUE(pScreen, BlockHandler, miSpriteBlockHandler);

    if (!pPriv->isUp && pPriv->shouldBeUp)
	miSpriteRestoreCursor (pScreen);
}

static void
miSpriteInstallColormap (pMap)
    ColormapPtr	pMap;
{
    ScreenPtr		pScreen = pMap->pScreen;
    miSpriteScreenPtr	pPriv;

    pPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;

    SCREEN_PROLOGUE(pScreen, InstallColormap);
    
    (*pScreen->InstallColormap) (pMap);

    SCREEN_EPILOGUE(pScreen, InstallColormap, miSpriteInstallColormap);

    pPriv->pInstalledMap = pMap;
    if (pPriv->pColormap != pMap)
    {
    	pPriv->checkPixels = TRUE;
	if (pPriv->isUp)
	    miSpriteRemoveCursor (pScreen);
    }
}

static void
miSpriteStoreColors (pMap, ndef, pdef)
    ColormapPtr	pMap;
    int		ndef;
    xColorItem	*pdef;
{
    ScreenPtr		pScreen = pMap->pScreen;
    miSpriteScreenPtr	pPriv;
    int			i;
    int			updated;
    VisualPtr		pVisual;

    pPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;

    SCREEN_PROLOGUE(pScreen, StoreColors);
    
    (*pScreen->StoreColors) (pMap, ndef, pdef);

    SCREEN_EPILOGUE(pScreen, StoreColors, miSpriteStoreColors);

    if (pPriv->pColormap == pMap)
    {
	updated = 0;
	pVisual = pMap->pVisual;
	if (pVisual->class == DirectColor)
	{
	    /* Direct color - match on any of the subfields */

#define MaskMatch(a,b,mask) (((a) & (pVisual->mask)) == ((b) & (pVisual->mask)))

#define UpdateDAC(plane,dac,mask) {\
    if (MaskMatch (pPriv->colors[plane].pixel,pdef[i].pixel,mask)) {\
	pPriv->colors[plane].dac = pdef[i].dac; \
	updated = 1; \
    } \
}

#define CheckDirect(plane) \
	    UpdateDAC(plane,red,redMask) \
	    UpdateDAC(plane,green,greenMask) \
	    UpdateDAC(plane,blue,blueMask)

	    for (i = 0; i < ndef; i++)
	    {
		CheckDirect (SOURCE_COLOR)
		CheckDirect (MASK_COLOR)
	    }
	}
	else
	{
	    /* PseudoColor/GrayScale - match on exact pixel */
	    for (i = 0; i < ndef; i++)
	    {
	    	if (pdef[i].pixel == pPriv->colors[SOURCE_COLOR].pixel)
	    	{
		    pPriv->colors[SOURCE_COLOR] = pdef[i];
		    if (++updated == 2)
		    	break;
	    	}
	    	if (pdef[i].pixel == pPriv->colors[MASK_COLOR].pixel)
	    	{
		    pPriv->colors[MASK_COLOR] = pdef[i];
		    if (++updated == 2)
		    	break;
	    	}
	    }
	}
    	if (updated)
    	{
	    pPriv->checkPixels = TRUE;
	    if (pPriv->isUp)
	    	miSpriteRemoveCursor (pScreen);
    	}
    }
}

static void
miSpriteFindColors (ScreenPtr pScreen)
{
    miSpriteScreenPtr	pScreenPriv = (miSpriteScreenPtr)
			    pScreen->devPrivates[miSpriteScreenIndex].ptr;
    CursorPtr		pCursor;
    xColorItem		*sourceColor, *maskColor;

    pCursor = pScreenPriv->pCursor;
    sourceColor = &pScreenPriv->colors[SOURCE_COLOR];
    maskColor = &pScreenPriv->colors[MASK_COLOR];
    if (pScreenPriv->pColormap != pScreenPriv->pInstalledMap ||
	!(pCursor->foreRed == sourceColor->red &&
	  pCursor->foreGreen == sourceColor->green &&
          pCursor->foreBlue == sourceColor->blue &&
	  pCursor->backRed == maskColor->red &&
	  pCursor->backGreen == maskColor->green &&
	  pCursor->backBlue == maskColor->blue))
    {
	pScreenPriv->pColormap = pScreenPriv->pInstalledMap;
	sourceColor->red = pCursor->foreRed;
	sourceColor->green = pCursor->foreGreen;
	sourceColor->blue = pCursor->foreBlue;
	FakeAllocColor (pScreenPriv->pColormap, sourceColor);
	maskColor->red = pCursor->backRed;
	maskColor->green = pCursor->backGreen;
	maskColor->blue = pCursor->backBlue;
	FakeAllocColor (pScreenPriv->pColormap, maskColor);
	/* "free" the pixels right away, don't let this confuse you */
	FakeFreeColor(pScreenPriv->pColormap, sourceColor->pixel);
	FakeFreeColor(pScreenPriv->pColormap, maskColor->pixel);
    }
    pScreenPriv->checkPixels = FALSE;
}

/*
 * BackingStore wrappers
 */

static void
miSpriteSaveDoomedAreas (pWin, pObscured, dx, dy)
    WindowPtr	pWin;
    RegionPtr	pObscured;
    int		dx, dy;
{
    ScreenPtr		pScreen;
    miSpriteScreenPtr   pScreenPriv;
    BoxRec		cursorBox;

    pScreen = pWin->drawable.pScreen;
    
    SCREEN_PROLOGUE (pScreen, SaveDoomedAreas);

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    if (pScreenPriv->isUp)
    {
	cursorBox = pScreenPriv->saved;

	if (dx || dy)
 	{
	    cursorBox.x1 += dx;
	    cursorBox.y1 += dy;
	    cursorBox.x2 += dx;
	    cursorBox.y2 += dy;
	}
	if (RECT_IN_REGION( pScreen, pObscured, &cursorBox) != rgnOUT)
	    miSpriteRemoveCursor (pScreen);
    }

    (*pScreen->SaveDoomedAreas) (pWin, pObscured, dx, dy);

    SCREEN_EPILOGUE (pScreen, SaveDoomedAreas, miSpriteSaveDoomedAreas);
}

static RegionPtr
miSpriteRestoreAreas (pWin, prgnExposed)
    WindowPtr	pWin;
    RegionPtr	prgnExposed;
{
    ScreenPtr		pScreen;
    miSpriteScreenPtr   pScreenPriv;
    RegionPtr		result;

    pScreen = pWin->drawable.pScreen;
    
    SCREEN_PROLOGUE (pScreen, RestoreAreas);

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    if (pScreenPriv->isUp)
    {
	if (RECT_IN_REGION( pScreen, prgnExposed, &pScreenPriv->saved) != rgnOUT)
	    miSpriteRemoveCursor (pScreen);
    }

    result = (*pScreen->RestoreAreas) (pWin, prgnExposed);

    SCREEN_EPILOGUE (pScreen, RestoreAreas, miSpriteRestoreAreas);

    return result;
}

/*
 * Window wrappers
 */

static void
miSpritePaintWindowBackground (pWin, pRegion, what)
    WindowPtr	pWin;
    RegionPtr	pRegion;
    int		what;
{
    ScreenPtr	    pScreen;
    miSpriteScreenPtr    pScreenPriv;

    pScreen = pWin->drawable.pScreen;

    SCREEN_PROLOGUE (pScreen, PaintWindowBackground);

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    if (pScreenPriv->isUp)
    {
	/*
	 * If the cursor is on the same screen as the window, check the
	 * region to paint for the cursor and remove it as necessary
	 */
	if (RECT_IN_REGION( pScreen, pRegion, &pScreenPriv->saved) != rgnOUT)
	    miSpriteRemoveCursor (pScreen);
    }

    (*pScreen->PaintWindowBackground) (pWin, pRegion, what);

    SCREEN_EPILOGUE (pScreen, PaintWindowBackground, miSpritePaintWindowBackground);
}

static void
miSpritePaintWindowBorder (pWin, pRegion, what)
    WindowPtr	pWin;
    RegionPtr	pRegion;
    int		what;
{
    ScreenPtr	    pScreen;
    miSpriteScreenPtr    pScreenPriv;

    pScreen = pWin->drawable.pScreen;

    SCREEN_PROLOGUE (pScreen, PaintWindowBorder);

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    if (pScreenPriv->isUp)
    {
	/*
	 * If the cursor is on the same screen as the window, check the
	 * region to paint for the cursor and remove it as necessary
	 */
	if (RECT_IN_REGION( pScreen, pRegion, &pScreenPriv->saved) != rgnOUT)
	    miSpriteRemoveCursor (pScreen);
    }

    (*pScreen->PaintWindowBorder) (pWin, pRegion, what);

    SCREEN_EPILOGUE (pScreen, PaintWindowBorder, miSpritePaintWindowBorder);
}

static void
miSpriteCopyWindow (pWin, ptOldOrg, pRegion)
    WindowPtr	pWin;
    DDXPointRec	ptOldOrg;
    RegionPtr	pRegion;
{
    ScreenPtr	    pScreen;
    miSpriteScreenPtr    pScreenPriv;
    BoxRec	    cursorBox;
    int		    dx, dy;

    pScreen = pWin->drawable.pScreen;

    SCREEN_PROLOGUE (pScreen, CopyWindow);

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    if (pScreenPriv->isUp)
    {
	/*
	 * check both the source and the destination areas.  The given
	 * region is source relative, so offset the cursor box by
	 * the delta position
	 */
	cursorBox = pScreenPriv->saved;
	dx = pWin->drawable.x - ptOldOrg.x;
	dy = pWin->drawable.y - ptOldOrg.y;
	cursorBox.x1 -= dx;
	cursorBox.x2 -= dx;
	cursorBox.y1 -= dy;
	cursorBox.y2 -= dy;
	if (RECT_IN_REGION( pScreen, pRegion, &pScreenPriv->saved) != rgnOUT ||
	    RECT_IN_REGION( pScreen, pRegion, &cursorBox) != rgnOUT)
	    miSpriteRemoveCursor (pScreen);
    }

    (*pScreen->CopyWindow) (pWin, ptOldOrg, pRegion);

    SCREEN_EPILOGUE (pScreen, CopyWindow, miSpriteCopyWindow);
}

static void
miSpriteClearToBackground (pWin, x, y, w, h, generateExposures)
    WindowPtr pWin;
    int x,y;
    int w,h;
    Bool generateExposures;
{
    ScreenPtr		pScreen;
    miSpriteScreenPtr	pScreenPriv;
    int			realw, realh;

    pScreen = pWin->drawable.pScreen;

    SCREEN_PROLOGUE (pScreen, ClearToBackground);

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    if (GC_CHECK(pWin))
    {
	if (!(realw = w))
	    realw = (int) pWin->drawable.width - x;
	if (!(realh = h))
	    realh = (int) pWin->drawable.height - y;
	if (ORG_OVERLAP(&pScreenPriv->saved, pWin->drawable.x, pWin->drawable.y,
			x, y, realw, realh))
	{
	    miSpriteRemoveCursor (pScreen);
	}
    }

    (*pScreen->ClearToBackground) (pWin, x, y, w, h, generateExposures);

    SCREEN_EPILOGUE (pScreen, ClearToBackground, miSpriteClearToBackground);
}

/*
 * GC Func wrappers
 */

static void
miSpriteValidateGC (pGC, changes, pDrawable)
    GCPtr	pGC;
    unsigned long	changes;
    DrawablePtr	pDrawable;
{
    GC_FUNC_PROLOGUE (pGC);

    (*pGC->funcs->ValidateGC) (pGC, changes, pDrawable);
    
    pGCPriv->wrapOps = NULL;
    if (pDrawable->type == DRAWABLE_WINDOW && ((WindowPtr) pDrawable)->viewable)
    {
	WindowPtr   pWin;
	RegionPtr   pRegion;

	pWin = (WindowPtr) pDrawable;
	pRegion = &pWin->clipList;
	if (pGC->subWindowMode == IncludeInferiors)
	    pRegion = &pWin->borderClip;
	if (REGION_NOTEMPTY(pDrawable->pScreen, pRegion))
	    pGCPriv->wrapOps = pGC->ops;
    }

    GC_FUNC_EPILOGUE (pGC);
}

static void
miSpriteChangeGC (pGC, mask)
    GCPtr	    pGC;
    unsigned long   mask;
{
    GC_FUNC_PROLOGUE (pGC);

    (*pGC->funcs->ChangeGC) (pGC, mask);
    
    GC_FUNC_EPILOGUE (pGC);
}

static void
miSpriteCopyGC (pGCSrc, mask, pGCDst)
    GCPtr	    pGCSrc, pGCDst;
    unsigned long   mask;
{
    GC_FUNC_PROLOGUE (pGCDst);

    (*pGCDst->funcs->CopyGC) (pGCSrc, mask, pGCDst);
    
    GC_FUNC_EPILOGUE (pGCDst);
}

static void
miSpriteDestroyGC (pGC)
    GCPtr   pGC;
{
    GC_FUNC_PROLOGUE (pGC);

    (*pGC->funcs->DestroyGC) (pGC);
    
    GC_FUNC_EPILOGUE (pGC);
}

static void
miSpriteChangeClip (pGC, type, pvalue, nrects)
    GCPtr   pGC;
    int		type;
    pointer	pvalue;
    int		nrects;
{
    GC_FUNC_PROLOGUE (pGC);

    (*pGC->funcs->ChangeClip) (pGC, type, pvalue, nrects);

    GC_FUNC_EPILOGUE (pGC);
}

static void
miSpriteCopyClip(pgcDst, pgcSrc)
    GCPtr pgcDst, pgcSrc;
{
    GC_FUNC_PROLOGUE (pgcDst);

    (* pgcDst->funcs->CopyClip)(pgcDst, pgcSrc);

    GC_FUNC_EPILOGUE (pgcDst);
}

static void
miSpriteDestroyClip(pGC)
    GCPtr	pGC;
{
    GC_FUNC_PROLOGUE (pGC);

    (* pGC->funcs->DestroyClip)(pGC);

    GC_FUNC_EPILOGUE (pGC);
}

/*
 * GC Op wrappers
 */

static void
miSpriteFillSpans(pDrawable, pGC, nInit, pptInit, pwidthInit, fSorted)
    DrawablePtr pDrawable;
    GCPtr	pGC;
    int		nInit;			/* number of spans to fill */
    DDXPointPtr pptInit;		/* pointer to list of start points */
    int		*pwidthInit;		/* pointer to list of n widths */
    int 	fSorted;
{
    GC_SETUP(pDrawable, pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
    {
	register DDXPointPtr    pts;
	register int    	*widths;
	register int    	nPts;

	for (pts = pptInit, widths = pwidthInit, nPts = nInit;
	     nPts--;
	     pts++, widths++)
 	{
	     if (SPN_OVERLAP(&pScreenPriv->saved,pts->y,pts->x,*widths))
	     {
		 miSpriteRemoveCursor (pDrawable->pScreen);
		 break;
	     }
	}
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->FillSpans) (pDrawable, pGC, nInit, pptInit, pwidthInit, fSorted);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpriteSetSpans(pDrawable, pGC, psrc, ppt, pwidth, nspans, fSorted)
    DrawablePtr		pDrawable;
    GCPtr		pGC;
    char		*psrc;
    register DDXPointPtr ppt;
    int			*pwidth;
    int			nspans;
    int			fSorted;
{
    GC_SETUP(pDrawable, pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
    {
	register DDXPointPtr    pts;
	register int    	*widths;
	register int    	nPts;

	for (pts = ppt, widths = pwidth, nPts = nspans;
	     nPts--;
	     pts++, widths++)
 	{
	     if (SPN_OVERLAP(&pScreenPriv->saved,pts->y,pts->x,*widths))
	     {
		 miSpriteRemoveCursor(pDrawable->pScreen);
		 break;
	     }
	}
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->SetSpans) (pDrawable, pGC, psrc, ppt, pwidth, nspans, fSorted);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpritePutImage(pDrawable, pGC, depth, x, y, w, h, leftPad, format, pBits)
    DrawablePtr	  pDrawable;
    GCPtr   	  pGC;
    int		  depth;
    int	    	  x;
    int	    	  y;
    int	    	  w;
    int	    	  h;
    int		  leftPad;
    int	    	  format;
    char    	  *pBits;
{
    GC_SETUP(pDrawable, pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
    {
	if (ORG_OVERLAP(&pScreenPriv->saved,pDrawable->x,pDrawable->y,
			x,y,w,h))
 	{
	    miSpriteRemoveCursor (pDrawable->pScreen);
	}
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->PutImage) (pDrawable, pGC, depth, x, y, w, h, leftPad, format, pBits);

    GC_OP_EPILOGUE (pGC);
}

static RegionPtr
miSpriteCopyArea (pSrc, pDst, pGC, srcx, srcy, w, h, dstx, dsty)
    DrawablePtr	  pSrc;
    DrawablePtr	  pDst;
    GCPtr   	  pGC;
    int	    	  srcx;
    int	    	  srcy;
    int	    	  w;
    int	    	  h;
    int	    	  dstx;
    int	    	  dsty;
{
    RegionPtr rgn;

    GC_SETUP(pDst, pGC);

    /* check destination/source overlap. */
    if (GC_CHECK((WindowPtr) pDst) &&
	 (ORG_OVERLAP(&pScreenPriv->saved,pDst->x,pDst->y,dstx,dsty,w,h) ||
	  ((pDst == pSrc) &&
	   ORG_OVERLAP(&pScreenPriv->saved,pSrc->x,pSrc->y,srcx,srcy,w,h))))
    {
	miSpriteRemoveCursor (pDst->pScreen);
    }
 
    GC_OP_PROLOGUE (pGC);

    rgn = (*pGC->ops->CopyArea) (pSrc, pDst, pGC, srcx, srcy, w, h,
				 dstx, dsty);

    GC_OP_EPILOGUE (pGC);

    return rgn;
}

static RegionPtr
miSpriteCopyPlane (pSrc, pDst, pGC, srcx, srcy, w, h, dstx, dsty, plane)
    DrawablePtr	  pSrc;
    DrawablePtr	  pDst;
    register GCPtr pGC;
    int     	  srcx,
		  srcy;
    int     	  w,
		  h;
    int     	  dstx,
		  dsty;
    unsigned long  plane;
{
    RegionPtr rgn;

    GC_SETUP(pDst, pGC);

    /*
     * check destination/source for overlap.
     */
    if (GC_CHECK((WindowPtr) pDst) &&
	(ORG_OVERLAP(&pScreenPriv->saved,pDst->x,pDst->y,dstx,dsty,w,h) ||
	 ((pDst == pSrc) &&
	  ORG_OVERLAP(&pScreenPriv->saved,pSrc->x,pSrc->y,srcx,srcy,w,h))))
    {
	miSpriteRemoveCursor (pDst->pScreen);
    }

    GC_OP_PROLOGUE (pGC);

    rgn = (*pGC->ops->CopyPlane) (pSrc, pDst, pGC, srcx, srcy, w, h,
				  dstx, dsty, plane);

    GC_OP_EPILOGUE (pGC);

    return rgn;
}

static void
miSpritePolyPoint (pDrawable, pGC, mode, npt, pptInit)
    DrawablePtr pDrawable;
    GCPtr	pGC;
    int		mode;		/* Origin or Previous */
    int		npt;
    xPoint 	*pptInit;
{
    xPoint	t;
    int		n;
    BoxRec	cursor;
    register xPoint *pts;

    GC_SETUP (pDrawable, pGC);

    if (npt && GC_CHECK((WindowPtr) pDrawable))
    {
	cursor.x1 = pScreenPriv->saved.x1 - pDrawable->x;
	cursor.y1 = pScreenPriv->saved.y1 - pDrawable->y;
	cursor.x2 = pScreenPriv->saved.x2 - pDrawable->x;
	cursor.y2 = pScreenPriv->saved.y2 - pDrawable->y;

	if (mode == CoordModePrevious)
	{
	    t.x = 0;
	    t.y = 0;
	    for (pts = pptInit, n = npt; n--; pts++)
	    {
		t.x += pts->x;
		t.y += pts->y;
		if (cursor.x1 <= t.x && t.x <= cursor.x2 &&
		    cursor.y1 <= t.y && t.y <= cursor.y2)
		{
		    miSpriteRemoveCursor (pDrawable->pScreen);
		    break;
		}
	    }
	}
	else
	{
	    for (pts = pptInit, n = npt; n--; pts++)
	    {
		if (cursor.x1 <= pts->x && pts->x <= cursor.x2 &&
		    cursor.y1 <= pts->y && pts->y <= cursor.y2)
		{
		    miSpriteRemoveCursor (pDrawable->pScreen);
		    break;
		}
	    }
	}
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->PolyPoint) (pDrawable, pGC, mode, npt, pptInit);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpritePolylines (pDrawable, pGC, mode, npt, pptInit)
    DrawablePtr	  pDrawable;
    GCPtr   	  pGC;
    int	    	  mode;
    int	    	  npt;
    DDXPointPtr	  pptInit;
{
    BoxPtr  cursor;
    register DDXPointPtr pts;
    int	    n;
    int	    x, y, x1, y1, x2, y2;
    int	    lw;
    int	    extra;

    GC_SETUP (pDrawable, pGC);

    if (npt && GC_CHECK((WindowPtr) pDrawable))
    {
	cursor = &pScreenPriv->saved;
	lw = pGC->lineWidth;
	x = pptInit->x + pDrawable->x;
	y = pptInit->y + pDrawable->y;

	if (npt == 1)
	{
	    extra = lw >> 1;
	    if (LINE_OVERLAP(cursor, x, y, x, y, extra))
		miSpriteRemoveCursor (pDrawable->pScreen);
	}
	else
	{
	    extra = lw >> 1;
	    /*
	     * mitered joins can project quite a way from
	     * the line end; the 11 degree miter limit limits
	     * this extension to 10.43 * lw / 2, rounded up
	     * and converted to int yields 6 * lw
	     */
	    if (pGC->joinStyle == JoinMiter)
		extra = 6 * lw;
	    else if (pGC->capStyle == CapProjecting)
		extra = lw;
	    for (pts = pptInit + 1, n = npt - 1; n--; pts++)
	    {
		x1 = x;
		y1 = y;
		if (mode == CoordModeOrigin)
		{
		    x2 = pDrawable->x + pts->x;
		    y2 = pDrawable->y + pts->y;
		}
		else
		{
		    x2 = x + pts->x;
		    y2 = y + pts->y;
		}
		x = x2;
		y = y2;
		LINE_SORT(x1, y1, x2, y2);
		if (LINE_OVERLAP(cursor, x1, y1, x2, y2, extra))
		{
		    miSpriteRemoveCursor (pDrawable->pScreen);
		    break;
		}
	    }
	}
    }
    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->Polylines) (pDrawable, pGC, mode, npt, pptInit);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpritePolySegment(pDrawable, pGC, nseg, pSegs)
    DrawablePtr pDrawable;
    GCPtr 	pGC;
    int		nseg;
    xSegment	*pSegs;
{
    int	    n;
    register xSegment *segs;
    BoxPtr  cursor;
    int	    x1, y1, x2, y2;
    int	    extra;

    GC_SETUP(pDrawable, pGC);

    if (nseg && GC_CHECK((WindowPtr) pDrawable))
    {
	cursor = &pScreenPriv->saved;
	extra = pGC->lineWidth >> 1;
	if (pGC->capStyle == CapProjecting)
	    extra = pGC->lineWidth;
	for (segs = pSegs, n = nseg; n--; segs++)
	{
	    x1 = segs->x1 + pDrawable->x;
	    y1 = segs->y1 + pDrawable->y;
	    x2 = segs->x2 + pDrawable->x;
	    y2 = segs->y2 + pDrawable->y;
	    LINE_SORT(x1, y1, x2, y2);
	    if (LINE_OVERLAP(cursor, x1, y1, x2, y2, extra))
	    {
		miSpriteRemoveCursor (pDrawable->pScreen);
		break;
	    }
	}
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->PolySegment) (pDrawable, pGC, nseg, pSegs);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpritePolyRectangle(pDrawable, pGC, nrects, pRects)
    DrawablePtr	pDrawable;
    GCPtr	pGC;
    int		nrects;
    xRectangle	*pRects;
{
    register xRectangle *rects;
    BoxPtr  cursor;
    int	    lw;
    int	    n;
    int     x1, y1, x2, y2;
    
    GC_SETUP (pDrawable, pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
    {
	lw = pGC->lineWidth >> 1;
	cursor = &pScreenPriv->saved;
	for (rects = pRects, n = nrects; n--; rects++)
	{
	    x1 = rects->x + pDrawable->x;
	    y1 = rects->y + pDrawable->y;
	    x2 = x1 + (int)rects->width;
	    y2 = y1 + (int)rects->height;
	    if (LINE_OVERLAP(cursor, x1, y1, x2, y1, lw) ||
		LINE_OVERLAP(cursor, x2, y1, x2, y2, lw) ||
		LINE_OVERLAP(cursor, x1, y2, x2, y2, lw) ||
		LINE_OVERLAP(cursor, x1, y1, x1, y2, lw))
	    {
		miSpriteRemoveCursor (pDrawable->pScreen);
		break;
	    }
	}
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->PolyRectangle) (pDrawable, pGC, nrects, pRects);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpritePolyArc(pDrawable, pGC, narcs, parcs)
    DrawablePtr	pDrawable;
    register GCPtr	pGC;
    int		narcs;
    xArc	*parcs;
{
    BoxPtr  cursor;
    int	    lw;
    int	    n;
    register xArc *arcs;
    
    GC_SETUP (pDrawable, pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
    {
	lw = pGC->lineWidth >> 1;
	cursor = &pScreenPriv->saved;
	for (arcs = parcs, n = narcs; n--; arcs++)
	{
	    if (ORG_OVERLAP (cursor, pDrawable->x, pDrawable->y,
			     arcs->x - lw, arcs->y - lw,
			     (int) arcs->width + pGC->lineWidth,
 			     (int) arcs->height + pGC->lineWidth))
	    {
		miSpriteRemoveCursor (pDrawable->pScreen);
		break;
	    }
	}
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->PolyArc) (pDrawable, pGC, narcs, parcs);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpriteFillPolygon(pDrawable, pGC, shape, mode, count, pPts)
    register DrawablePtr pDrawable;
    register GCPtr	pGC;
    int			shape, mode;
    int			count;
    DDXPointPtr		pPts;
{
    int x, y, minx, miny, maxx, maxy;
    register DDXPointPtr pts;
    int n;

    GC_SETUP (pDrawable, pGC);

    if (count && GC_CHECK((WindowPtr) pDrawable))
    {
	x = pDrawable->x;
	y = pDrawable->y;
	pts = pPts;
	minx = maxx = pts->x;
	miny = maxy = pts->y;
	pts++;
	n = count - 1;

	if (mode == CoordModeOrigin)
	{
	    for (; n--; pts++)
	    {
		if (pts->x < minx)
		    minx = pts->x;
		else if (pts->x > maxx)
		    maxx = pts->x;
		if (pts->y < miny)
		    miny = pts->y;
		else if (pts->y > maxy)
		    maxy = pts->y;
	    }
	    minx += x;
	    miny += y;
	    maxx += x;
	    maxy += y;
	}
	else
	{
	    x += minx;
	    y += miny;
	    minx = maxx = x;
	    miny = maxy = y;
	    for (; n--; pts++)
	    {
		x += pts->x;
		y += pts->y;
		if (x < minx)
		    minx = x;
		else if (x > maxx)
		    maxx = x;
		if (y < miny)
		    miny = y;
		else if (y > maxy)
		    maxy = y;
	    }
	}
	if (BOX_OVERLAP(&pScreenPriv->saved,minx,miny,maxx,maxy))
	    miSpriteRemoveCursor (pDrawable->pScreen);
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->FillPolygon) (pDrawable, pGC, shape, mode, count, pPts);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpritePolyFillRect(pDrawable, pGC, nrectFill, prectInit)
    DrawablePtr pDrawable;
    GCPtr	pGC;
    int		nrectFill; 	/* number of rectangles to fill */
    xRectangle	*prectInit;  	/* Pointer to first rectangle to fill */
{
    GC_SETUP(pDrawable, pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
    {
	register int	    nRect;
	register xRectangle *pRect;
	register int	    xorg, yorg;

	xorg = pDrawable->x;
	yorg = pDrawable->y;

	for (nRect = nrectFill, pRect = prectInit; nRect--; pRect++) {
	    if (ORGRECT_OVERLAP(&pScreenPriv->saved,xorg,yorg,pRect)){
		miSpriteRemoveCursor(pDrawable->pScreen);
		break;
	    }
	}
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->PolyFillRect) (pDrawable, pGC, nrectFill, prectInit);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpritePolyFillArc(pDrawable, pGC, narcs, parcs)
    DrawablePtr	pDrawable;
    GCPtr	pGC;
    int		narcs;
    xArc	*parcs;
{
    GC_SETUP(pDrawable, pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
    {
	register int	n;
	BoxPtr		cursor;
	register xArc *arcs;

	cursor = &pScreenPriv->saved;

	for (arcs = parcs, n = narcs; n--; arcs++)
	{
	    if (ORG_OVERLAP(cursor, pDrawable->x, pDrawable->y,
			    arcs->x, arcs->y,
 			    (int) arcs->width, (int) arcs->height))
	    {
		miSpriteRemoveCursor (pDrawable->pScreen);
		break;
	    }
	}
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->PolyFillArc) (pDrawable, pGC, narcs, parcs);

    GC_OP_EPILOGUE (pGC);
}

/*
 * general Poly/Image text function.  Extract glyph information,
 * compute bounding box and remove cursor if it is overlapped.
 */

static Bool
miSpriteTextOverlap (
    DrawablePtr   pDraw,
    FontPtr	  font,
    int		  x,
    int		  y,
    unsigned int  n,
    CharInfoPtr   *charinfo,
    Bool	  imageblt,
    unsigned int  w,
    BoxPtr	  cursorBox)
{
    ExtentInfoRec extents;

    x += pDraw->x;
    y += pDraw->y;

    if (FONTMINBOUNDS(font,characterWidth) >= 0)
    {
	/* compute an approximate (but covering) bounding box */
	if (!imageblt || (charinfo[0]->metrics.leftSideBearing < 0))
	    extents.overallLeft = charinfo[0]->metrics.leftSideBearing;
	else
	    extents.overallLeft = 0;
	if (w)
	    extents.overallRight = w - charinfo[n-1]->metrics.characterWidth;
	else
	    extents.overallRight = FONTMAXBOUNDS(font,characterWidth)
				    * (n - 1);
	if (imageblt && (charinfo[n-1]->metrics.characterWidth >
			 charinfo[n-1]->metrics.rightSideBearing))
	    extents.overallRight += charinfo[n-1]->metrics.characterWidth;
	else
	    extents.overallRight += charinfo[n-1]->metrics.rightSideBearing;
	if (imageblt && FONTASCENT(font) > FONTMAXBOUNDS(font,ascent))
	    extents.overallAscent = FONTASCENT(font);
	else
	    extents.overallAscent = FONTMAXBOUNDS(font, ascent);
	if (imageblt && FONTDESCENT(font) > FONTMAXBOUNDS(font,descent))
	    extents.overallDescent = FONTDESCENT(font);
	else
	    extents.overallDescent = FONTMAXBOUNDS(font,descent);
	if (!BOX_OVERLAP(cursorBox,
			 x + extents.overallLeft,
			 y - extents.overallAscent,
			 x + extents.overallRight,
			 y + extents.overallDescent))
	    return FALSE;
	else if (imageblt && w)
	    return TRUE;
	/* if it does overlap, fall through and compute exactly, because
	 * taking down the cursor is expensive enough to make this worth it
	 */
    }
    QueryGlyphExtents(font, charinfo, n, &extents);
    if (imageblt)
    {
	if (extents.overallWidth > extents.overallRight)
	    extents.overallRight = extents.overallWidth;
	if (extents.overallWidth < extents.overallLeft)
	    extents.overallLeft = extents.overallWidth;
	if (extents.overallLeft > 0)
	    extents.overallLeft = 0;
	if (extents.fontAscent > extents.overallAscent)
	    extents.overallAscent = extents.fontAscent;
	if (extents.fontDescent > extents.overallDescent)
	    extents.overallDescent = extents.fontDescent;
    }
    return (BOX_OVERLAP(cursorBox,
			x + extents.overallLeft,
			y - extents.overallAscent,
			x + extents.overallRight,
			y + extents.overallDescent));
}

/*
 * values for textType:
 */
#define TT_POLY8   0
#define TT_IMAGE8  1
#define TT_POLY16  2
#define TT_IMAGE16 3

static int 
miSpriteText (
    DrawablePtr	    pDraw,
    GCPtr	    pGC,
    int		    x,
    int		    y,
    unsigned long    count,
    char	    *chars,
    FontEncoding    fontEncoding,
    Bool	    textType,
    BoxPtr	    cursorBox)
{
    CharInfoPtr *charinfo;
    register CharInfoPtr *info;
    unsigned long i;
    unsigned int  n;
    int		  w;

    Bool imageblt;

    imageblt = (textType == TT_IMAGE8) || (textType == TT_IMAGE16);

    charinfo = (CharInfoPtr *) ALLOCATE_LOCAL(count * sizeof(CharInfoPtr));
    if (!charinfo)
	return x;

    GetGlyphs(pGC->font, count, (unsigned char *)chars,
	      fontEncoding, &i, charinfo);
    n = (unsigned int)i;
    w = 0;
    if (!imageblt)
	for (info = charinfo; i--; info++)
	    w += (*info)->metrics.characterWidth;

    if (n != 0) {
	if (miSpriteTextOverlap(pDraw, pGC->font, x, y, n, charinfo, imageblt, w, cursorBox))
	    miSpriteRemoveCursor(pDraw->pScreen);

#ifdef AVOID_GLYPHBLT
	/*
	 * On displays like Apollos, which do not optimize the GlyphBlt functions because they
	 * convert fonts to their internal form in RealizeFont and optimize text directly, we
	 * want to invoke the text functions here, not the GlyphBlt functions.
	 */
	switch (textType)
	{
	case TT_POLY8:
	    (*pGC->ops->PolyText8)(pDraw, pGC, x, y, (int)count, chars);
	    break;
	case TT_IMAGE8:
	    (*pGC->ops->ImageText8)(pDraw, pGC, x, y, (int)count, chars);
	    break;
	case TT_POLY16:
	    (*pGC->ops->PolyText16)(pDraw, pGC, x, y, (int)count,
				    (unsigned short *)chars);
	    break;
	case TT_IMAGE16:
	    (*pGC->ops->ImageText16)(pDraw, pGC, x, y, (int)count,
				     (unsigned short *)chars);
	    break;
	}
#else /* don't AVOID_GLYPHBLT */
	/*
	 * On the other hand, if the device does use GlyphBlt ultimately to do text, we
	 * don't want to slow it down by invoking the text functions and having them call
	 * GetGlyphs all over again, so we go directly to the GlyphBlt functions here.
	 */
	if (imageblt) {
	    (*pGC->ops->ImageGlyphBlt)(pDraw, pGC, x, y, n, charinfo,
				       FONTGLYPHS(pGC->font));
	} else {
	    (*pGC->ops->PolyGlyphBlt)(pDraw, pGC, x, y, n, charinfo,
				      FONTGLYPHS(pGC->font));
	}
#endif /* AVOID_GLYPHBLT */
    }
    DEALLOCATE_LOCAL(charinfo);
    return x + w;
}

static int
miSpritePolyText8(pDrawable, pGC, x, y, count, chars)
    DrawablePtr pDrawable;
    GCPtr	pGC;
    int		x, y;
    int 	count;
    char	*chars;
{
    int	ret;

    GC_SETUP (pDrawable, pGC);

    GC_OP_PROLOGUE (pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
	ret = miSpriteText (pDrawable, pGC, x, y, (unsigned long)count, chars,
			    Linear8Bit, TT_POLY8, &pScreenPriv->saved);
    else
	ret = (*pGC->ops->PolyText8) (pDrawable, pGC, x, y, count, chars);

    GC_OP_EPILOGUE (pGC);
    return ret;
}

static int
miSpritePolyText16(pDrawable, pGC, x, y, count, chars)
    DrawablePtr pDrawable;
    GCPtr	pGC;
    int		x, y;
    int		count;
    unsigned short *chars;
{
    int	ret;

    GC_SETUP(pDrawable, pGC);

    GC_OP_PROLOGUE (pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
	ret = miSpriteText (pDrawable, pGC, x, y, (unsigned long)count,
			    (char *)chars,
			    FONTLASTROW(pGC->font) == 0 ?
			    Linear16Bit : TwoD16Bit, TT_POLY16, &pScreenPriv->saved);
    else
	ret = (*pGC->ops->PolyText16) (pDrawable, pGC, x, y, count, chars);

    GC_OP_EPILOGUE (pGC);
    return ret;
}

static void
miSpriteImageText8(pDrawable, pGC, x, y, count, chars)
    DrawablePtr pDrawable;
    GCPtr	pGC;
    int		x, y;
    int		count;
    char	*chars;
{
    GC_SETUP(pDrawable, pGC);

    GC_OP_PROLOGUE (pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
	(void) miSpriteText (pDrawable, pGC, x, y, (unsigned long)count,
			     chars, Linear8Bit, TT_IMAGE8, &pScreenPriv->saved);
    else
	(*pGC->ops->ImageText8) (pDrawable, pGC, x, y, count, chars);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpriteImageText16(pDrawable, pGC, x, y, count, chars)
    DrawablePtr pDrawable;
    GCPtr	pGC;
    int		x, y;
    int		count;
    unsigned short *chars;
{
    GC_SETUP(pDrawable, pGC);

    GC_OP_PROLOGUE (pGC);

    if (GC_CHECK((WindowPtr) pDrawable))
	(void) miSpriteText (pDrawable, pGC, x, y, (unsigned long)count,
			     (char *)chars,
			    FONTLASTROW(pGC->font) == 0 ?
			    Linear16Bit : TwoD16Bit, TT_IMAGE16, &pScreenPriv->saved);
    else
	(*pGC->ops->ImageText16) (pDrawable, pGC, x, y, count, chars);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpriteImageGlyphBlt(pDrawable, pGC, x, y, nglyph, ppci, pglyphBase)
    DrawablePtr pDrawable;
    GCPtr 	pGC;
    int 	x, y;
    unsigned int nglyph;
    CharInfoPtr *ppci;		/* array of character info */
    pointer 	pglyphBase;	/* start of array of glyphs */
{
    GC_SETUP(pDrawable, pGC);

    GC_OP_PROLOGUE (pGC);

    if (GC_CHECK((WindowPtr) pDrawable) &&
	miSpriteTextOverlap (pDrawable, pGC->font, x, y, nglyph, ppci, TRUE, 0, &pScreenPriv->saved))
    {
	miSpriteRemoveCursor(pDrawable->pScreen);
    }
    (*pGC->ops->ImageGlyphBlt) (pDrawable, pGC, x, y, nglyph, ppci, pglyphBase);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpritePolyGlyphBlt(pDrawable, pGC, x, y, nglyph, ppci, pglyphBase)
    DrawablePtr pDrawable;
    GCPtr	pGC;
    int 	x, y;
    unsigned int nglyph;
    CharInfoPtr *ppci;		/* array of character info */
    pointer	pglyphBase;	/* start of array of glyphs */
{
    GC_SETUP (pDrawable, pGC);

    GC_OP_PROLOGUE (pGC);

    if (GC_CHECK((WindowPtr) pDrawable) &&
	miSpriteTextOverlap (pDrawable, pGC->font, x, y, nglyph, ppci, FALSE, 0, &pScreenPriv->saved))
    {
	miSpriteRemoveCursor(pDrawable->pScreen);
    }
    (*pGC->ops->PolyGlyphBlt) (pDrawable, pGC, x, y, nglyph, ppci, pglyphBase);

    GC_OP_EPILOGUE (pGC);
}

static void
miSpritePushPixels(pGC, pBitMap, pDrawable, w, h, x, y)
    GCPtr	pGC;
    PixmapPtr	pBitMap;
    DrawablePtr pDrawable;
    int		w, h, x, y;
{
    GC_SETUP(pDrawable, pGC);

    if (GC_CHECK((WindowPtr) pDrawable) &&
	ORG_OVERLAP(&pScreenPriv->saved,pDrawable->x,pDrawable->y,x,y,w,h))
    {
	miSpriteRemoveCursor (pDrawable->pScreen);
    }

    GC_OP_PROLOGUE (pGC);

    (*pGC->ops->PushPixels) (pGC, pBitMap, pDrawable, w, h, x, y);

    GC_OP_EPILOGUE (pGC);
}

#ifdef NEED_LINEHELPER
/*
 * I don't expect this routine will ever be called, as the GC
 * will have been unwrapped for the line drawing
 */

static void
miSpriteLineHelper()
{
    FatalError("miSpriteLineHelper called\n");
}
#endif

#ifdef RENDER

# define mod(a,b)	((b) == 1 ? 0 : (a) >= 0 ? (a) % (b) : (b) - (-a) % (b))

static void
miSpritePictureOverlap (PicturePtr  pPict,
			INT16	    x,
			INT16	    y,
			CARD16	    w,
			CARD16	    h)
{
    if (pPict->pDrawable->type == DRAWABLE_WINDOW)
    {
	WindowPtr		pWin = (WindowPtr) (pPict->pDrawable);
	miSpriteScreenPtr	pScreenPriv = (miSpriteScreenPtr)
	    pPict->pDrawable->pScreen->devPrivates[miSpriteScreenIndex].ptr;
	if (GC_CHECK(pWin))
	{
	    if (pPict->repeat)
	    {
		x = mod(x,pWin->drawable.width);
		y = mod(y,pWin->drawable.height);
	    }
	    if (ORG_OVERLAP (&pScreenPriv->saved, pWin->drawable.x, pWin->drawable.y,
			     x, y, w, h))
		miSpriteRemoveCursor (pWin->drawable.pScreen);
	}
    }
}

#define PICTURE_PROLOGUE(ps, pScreenPriv, field) \
    ps->field = pScreenPriv->field

#define PICTURE_EPILOGUE(ps, field, wrap) \
    ps->field = wrap

static void
miSpriteComposite(CARD8	op,
		  PicturePtr pSrc,
		  PicturePtr pMask,
		  PicturePtr pDst,
		  INT16	xSrc,
		  INT16	ySrc,
		  INT16	xMask,
		  INT16	yMask,
		  INT16	xDst,
		  INT16	yDst,
		  CARD16	width,
		  CARD16	height)
{
    ScreenPtr		pScreen = pDst->pDrawable->pScreen;
    PictureScreenPtr	ps = GetPictureScreen(pScreen);
    miSpriteScreenPtr	pScreenPriv;

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    PICTURE_PROLOGUE(ps, pScreenPriv, Composite);
    miSpritePictureOverlap (pSrc, xSrc, ySrc, width, height);
    if (pMask)
	miSpritePictureOverlap (pMask, xMask, yMask, width, height);
    miSpritePictureOverlap (pDst, xDst, yDst, width, height);

    (*ps->Composite) (op,
		       pSrc,
		       pMask,
		       pDst,
		       xSrc,
		       ySrc,
		       xMask,
		       yMask,
		       xDst,
		       yDst,
		       width,
		       height);
    
    PICTURE_EPILOGUE(ps, Composite, miSpriteComposite);
}

static void
miSpriteGlyphs(CARD8		op,
	       PicturePtr	pSrc,
	       PicturePtr	pDst,
	       PictFormatPtr	maskFormat,
	       INT16		xSrc,
	       INT16		ySrc,
	       int		nlist,
	       GlyphListPtr	list,
	       GlyphPtr		*glyphs)
{
    ScreenPtr		pScreen = pDst->pDrawable->pScreen;
    PictureScreenPtr	ps = GetPictureScreen(pScreen);
    miSpriteScreenPtr	pScreenPriv;

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    PICTURE_PROLOGUE(ps, pScreenPriv, Glyphs);
    if (pSrc->pDrawable->type == DRAWABLE_WINDOW)
    {
	WindowPtr   pSrcWin = (WindowPtr) (pSrc->pDrawable);

	if (GC_CHECK(pSrcWin))
	    miSpriteRemoveCursor (pScreen);
    }
    if (pDst->pDrawable->type == DRAWABLE_WINDOW)
    {
	WindowPtr   pDstWin = (WindowPtr) (pDst->pDrawable);

	if (GC_CHECK(pDstWin))
	{
	    BoxRec  extents;

	    miGlyphExtents (nlist, list, glyphs, &extents);
	    if (BOX_OVERLAP(&pScreenPriv->saved,
			    extents.x1 + pDstWin->drawable.x,
			    extents.y1 + pDstWin->drawable.y,
			    extents.x2 + pDstWin->drawable.x,
			    extents.y2 + pDstWin->drawable.y))
	    {
		miSpriteRemoveCursor (pScreen);
	    }
	}
    }
    
    (*ps->Glyphs) (op, pSrc, pDst, maskFormat, xSrc, ySrc, nlist, list, glyphs);
    
    PICTURE_EPILOGUE (ps, Glyphs, miSpriteGlyphs);
}
#endif

/*
 * miPointer interface routines
 */

#define SPRITE_PAD  8

static Bool
miSpriteRealizeCursor (pScreen, pCursor)
    ScreenPtr	pScreen;
    CursorPtr	pCursor;
{
    miSpriteScreenPtr	pScreenPriv;

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    if (pCursor == pScreenPriv->pCursor)
	pScreenPriv->checkPixels = TRUE;
    return (*pScreenPriv->funcs->RealizeCursor) (pScreen, pCursor);
}

static Bool
miSpriteUnrealizeCursor (pScreen, pCursor)
    ScreenPtr	pScreen;
    CursorPtr	pCursor;
{
    miSpriteScreenPtr	pScreenPriv;

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    return (*pScreenPriv->funcs->UnrealizeCursor) (pScreen, pCursor);
}

static void
miSpriteSetCursor (pScreen, pCursor, x, y)
    ScreenPtr	pScreen;
    CursorPtr	pCursor;
    int		x;
    int		y;
{
    miSpriteScreenPtr	pScreenPriv;

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    if (!pCursor)
    {
    	pScreenPriv->shouldBeUp = FALSE;
    	if (pScreenPriv->isUp)
	    miSpriteRemoveCursor (pScreen);
	pScreenPriv->pCursor = 0;
	return;
    }
    pScreenPriv->shouldBeUp = TRUE;
    if (pScreenPriv->x == x &&
	pScreenPriv->y == y &&
	pScreenPriv->pCursor == pCursor &&
	!pScreenPriv->checkPixels)
    {
	return;
    }
    pScreenPriv->x = x;
    pScreenPriv->y = y;
    pScreenPriv->pCacheWin = NullWindow;
    if (pScreenPriv->checkPixels || pScreenPriv->pCursor != pCursor)
    {
	pScreenPriv->pCursor = pCursor;
	miSpriteFindColors (pScreen);
    }
    if (pScreenPriv->isUp) {
	int	sx, sy;
	/*
	 * check to see if the old saved region
	 * encloses the new sprite, in which case we use
	 * the flicker-free MoveCursor primitive.
	 */
	sx = pScreenPriv->x - (int)pCursor->bits->xhot;
	sy = pScreenPriv->y - (int)pCursor->bits->yhot;
	if (sx + (int) pCursor->bits->width >= pScreenPriv->saved.x1 &&
	    sx < pScreenPriv->saved.x2 &&
	    sy + (int) pCursor->bits->height >= pScreenPriv->saved.y1 &&
	    sy < pScreenPriv->saved.y2 &&
	    (int) pCursor->bits->width + (2 * SPRITE_PAD) ==
		pScreenPriv->saved.x2 - pScreenPriv->saved.x1 &&
	    (int) pCursor->bits->height + (2 * SPRITE_PAD) ==
		pScreenPriv->saved.y2 - pScreenPriv->saved.y1
	    )
	{
	    pScreenPriv->isUp = FALSE;
	    if (!(sx >= pScreenPriv->saved.x1 &&
	      	  sx + (int)pCursor->bits->width < pScreenPriv->saved.x2 &&
	      	  sy >= pScreenPriv->saved.y1 &&
	      	  sy + (int)pCursor->bits->height < pScreenPriv->saved.y2))
	    {
		int oldx1, oldy1, dx, dy;

		oldx1 = pScreenPriv->saved.x1;
		oldy1 = pScreenPriv->saved.y1;
		dx = oldx1 - (sx - SPRITE_PAD);
		dy = oldy1 - (sy - SPRITE_PAD);
		pScreenPriv->saved.x1 -= dx;
		pScreenPriv->saved.y1 -= dy;
		pScreenPriv->saved.x2 -= dx;
		pScreenPriv->saved.y2 -= dy;
		(void) (*pScreenPriv->funcs->ChangeSave) (pScreen,
				pScreenPriv->saved.x1,
 				pScreenPriv->saved.y1,
				pScreenPriv->saved.x2 - pScreenPriv->saved.x1,
				pScreenPriv->saved.y2 - pScreenPriv->saved.y1,
				dx, dy);
	    }
	    (void) (*pScreenPriv->funcs->MoveCursor) (pScreen, pCursor,
				  pScreenPriv->saved.x1,
 				  pScreenPriv->saved.y1,
				  pScreenPriv->saved.x2 - pScreenPriv->saved.x1,
				  pScreenPriv->saved.y2 - pScreenPriv->saved.y1,
				  sx - pScreenPriv->saved.x1,
				  sy - pScreenPriv->saved.y1,
				  pScreenPriv->colors[SOURCE_COLOR].pixel,
				  pScreenPriv->colors[MASK_COLOR].pixel);
	    pScreenPriv->isUp = TRUE;
	}
	else
	{
	    miSpriteRemoveCursor (pScreen);
	}
    }
    if (!pScreenPriv->isUp && pScreenPriv->pCursor)
	miSpriteRestoreCursor (pScreen);
}

static void
miSpriteMoveCursor (pScreen, x, y)
    ScreenPtr	pScreen;
    int		x, y;
{
    miSpriteScreenPtr	pScreenPriv;

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    miSpriteSetCursor (pScreen, pScreenPriv->pCursor, x, y);
}

/*
 * undraw/draw cursor
 */

static void
miSpriteRemoveCursor (pScreen)
    ScreenPtr	pScreen;
{
    miSpriteScreenPtr   pScreenPriv;

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    pScreenPriv->isUp = FALSE;
    pScreenPriv->pCacheWin = NullWindow;
    if (!(*pScreenPriv->funcs->RestoreUnderCursor) (pScreen,
					 pScreenPriv->saved.x1,
					 pScreenPriv->saved.y1,
					 pScreenPriv->saved.x2 - pScreenPriv->saved.x1,
					 pScreenPriv->saved.y2 - pScreenPriv->saved.y1))
    {
	pScreenPriv->isUp = TRUE;
    }
}

/*
 * Called from the block handler, restores the cursor
 * before waiting for something to do.
 */

static void
miSpriteRestoreCursor (pScreen)
    ScreenPtr	pScreen;
{
    miSpriteScreenPtr   pScreenPriv;
    int			x, y;
    CursorPtr		pCursor;

    miSpriteComputeSaved (pScreen);
    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    pCursor = pScreenPriv->pCursor;
    x = pScreenPriv->x - (int)pCursor->bits->xhot;
    y = pScreenPriv->y - (int)pCursor->bits->yhot;
    if ((*pScreenPriv->funcs->SaveUnderCursor) (pScreen,
				      pScreenPriv->saved.x1,
				      pScreenPriv->saved.y1,
				      pScreenPriv->saved.x2 - pScreenPriv->saved.x1,
				      pScreenPriv->saved.y2 - pScreenPriv->saved.y1))
    {
	if (pScreenPriv->checkPixels)
	    miSpriteFindColors (pScreen);
	if ((*pScreenPriv->funcs->PutUpCursor) (pScreen, pCursor, x, y,
				  pScreenPriv->colors[SOURCE_COLOR].pixel,
				  pScreenPriv->colors[MASK_COLOR].pixel))
	    pScreenPriv->isUp = TRUE;
    }
}

/*
 * compute the desired area of the screen to save
 */

static void
miSpriteComputeSaved (pScreen)
    ScreenPtr	pScreen;
{
    miSpriteScreenPtr   pScreenPriv;
    int		    x, y, w, h;
    int		    wpad, hpad;
    CursorPtr	    pCursor;

    pScreenPriv = (miSpriteScreenPtr) pScreen->devPrivates[miSpriteScreenIndex].ptr;
    pCursor = pScreenPriv->pCursor;
    x = pScreenPriv->x - (int)pCursor->bits->xhot;
    y = pScreenPriv->y - (int)pCursor->bits->yhot;
    w = pCursor->bits->width;
    h = pCursor->bits->height;
    wpad = SPRITE_PAD;
    hpad = SPRITE_PAD;
    pScreenPriv->saved.x1 = x - wpad;
    pScreenPriv->saved.y1 = y - hpad;
    pScreenPriv->saved.x2 = pScreenPriv->saved.x1 + w + wpad * 2;
    pScreenPriv->saved.y2 = pScreenPriv->saved.y1 + h + hpad * 2;
}