mbufbf.c

远程桌面连接工具

/*

Copyright (c) 1989  X Consortium

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

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
X CONSORTIUM 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 X Consortium 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 X Consortium.

*/

/* $XConsortium: mbufbf.c,v 1.5 94/04/17 20:32:53 dpw Exp $ */
/* $XFree86: xc/programs/Xserver/Xext/mbufbf.c,v 3.0 1994/05/08 05:17:30 dawes Exp $ */

#define NEED_REPLIES
#define NEED_EVENTS
#include <stdio.h>
#include "X.h"
#include "Xproto.h"
#include "misc.h"
#include "os.h"
#include "windowstr.h"
#include "scrnintstr.h"
#include "pixmapstr.h"
#include "extnsionst.h"
#include "dixstruct.h"
#include "resource.h"
#include "opaque.h"
#include "regionstr.h"
#include "gcstruct.h"
#include "inputstr.h"
#include "validate.h"
#ifndef MINIX
#include <sys/time.h>
#endif

#define _MULTIBUF_SERVER_	/* don't want Xlib structures */
#define _MULTIBUF_BUFFER_
#include "multibufst.h"

/* 
Support for doublebuffer hardare

This code is designed to support doublebuffer hardware where the
displayed buffer is selected on a per-pixel basis by an additional bit
plane, called the select plane. It could probably be easily modified
to work with systems that use window-id planes.

This is done by creating a new drawable type, DRAWABLE_BUFFER. The
type has the same exact layout as a window drawable. Your code should
treat a DRAWABLE_BUFFER the same as it would tread a DRAWABLE_WINDOW
when handling the gc drawing functions. In addition, PaintWindowBackground,
CopyWindow, and all of the gc drawing functions to be able to draw into both
framebuffers. Which framebuffer to draw into is selected by the contents of
	pWin->devPrivates[frameWindowPrivateIndex].
The content of the devPrivate is either from frameBuffer[0] or
frameBuffer[1], depending on which buffer is being drawn into. When
	pWin->devPrivates[frameWindowPrivateIndex] == frameBuffer[0],
the functions should draw into the front framebuffer. When
	pWin->devPrivates[frameWindowPrivateIndex] == frameBuffer[1],
the functions should draw into the back framebuffer.

In addition, you need to provide a function that allows you to copy
bits between the buffers (optional since CopyArea can be used) and a
function that draws into the select plane. Then, you need to register
your functions and other information, by calling:

void
RegisterDoubleBufferHardware(pScreen, nInfo, pInfo, frameBuffer, selectPlane,
			     CopyBufferBitsFunc, DrawSelectPlaneFunc)
    int			nInfo;
    xMbufBufferInfo	*pInfo;
    DevUnion		*frameBuffer;
    DevUnion		selectPlane;

"pInfo" is an array indicating which visuals and depths that double
buffering is supported on. "nInfo" is the length of the array.

"frameBuffer" is array of length 2. The contents of the array element
is ddx-specific. The content of frameBuffer[0] should, when placed in
the window private, indicate that framebuffer 0 should be drawn into.
The contents of frameBuffer[1], when placed into the window private,
should indicate that framebuffer 1 should be drawn into.

"selectPlane" is ddx-specific. It should contain information
neccessary for your displayProc to access the select plane.
It is passed to DrawSelectPlaneFunc.

"CopyBufferBitsFunc" is a ddx-specific function that copies from one
buffer of a multibuffered window to another buffer. If the CopyBufferBitsFunc
is NULL, a default function will be used that calls pScreen->CopyArea.

    void CopyBufferBitsFunc(pMBWindow, srcBufferNum, dstBufferNum)
        mbufWindowPtr pMBWindow;
        int srcBufferNum, dstBufferNum;

"DrawSelectPlaneFunc" is a ddx-specific function that fills the
regions "prgn" of select plane with the value "bufferNum". If 
selectPlane is a DrawablePtr (such as a PixmapPtr), you can pass
NULL for DrawSelectPlaneFunc, a default function will be used that
calls FillRectangle on the selectPlane.

    void DrawSelectPlaneFunc(pScreen, selectPlane, prgn, bufferNum)
        ScreenPtr	pScreen;
        DevUnion	selectPlane;
        RegionPtr	prgn;
        long		bufferNum;

...
...
...

*/

#define MAX_BUFFERS  2	/* Only supports 2 buffers */
#define FRONT_BUFFER 0
#define BACK_BUFFER  1


/* Buffer drawables have the same structure as window drawables */
typedef WindowRec BufferRec;
typedef WindowPtr BufferPtr;


/*
 * Call RegisterHdwrBuffer for every screen that has doublebuffer hardware. 
 */

static int		bufNumInfo[MAXSCREENS];
static xMbufBufferInfo	*bufInfo[MAXSCREENS];
static DevUnion		*bufFrameBuffer[MAXSCREENS];
static DevUnion		bufselectPlane[MAXSCREENS];
static void		(* bufCopyBufferBitsFunc[MAXSCREENS])();
static void		(* bufDrawSelectPlaneFunc[MAXSCREENS])();

static Bool bufMultibufferInit();


void
RegisterDoubleBufferHardware(pScreen, nInfo, pInfo, frameBuffer, selectPlane,
			     CopyBufferBitsFunc, DrawSelectPlaneFunc)
    ScreenPtr		pScreen;
    int			nInfo;
    xMbufBufferInfo	*pInfo;
    DevUnion		*frameBuffer;
    DevUnion		selectPlane;
    void		(* CopyBufferBitsFunc)();
    void		(* DrawSelectPlaneFunc)();
{
    bufNumInfo[pScreen->myNum]     = nInfo;
    bufInfo[pScreen->myNum]        = pInfo;
    bufFrameBuffer[pScreen->myNum] = frameBuffer;
    bufselectPlane[pScreen->myNum] = selectPlane;

    bufCopyBufferBitsFunc[pScreen->myNum]  = CopyBufferBitsFunc;
    bufDrawSelectPlaneFunc[pScreen->myNum] = DrawSelectPlaneFunc;

    /* Register ourselves with device-independent multibuffers code */
    RegisterMultibufferInit(pScreen, bufMultibufferInit);
}


/*
 * Called by Multibuffer extension initialization.
 * Initializes mbufScreenRec and its devPrivate.
 */
    
static Bool NoopDDA_True() { return TRUE; }
static Bool bufPositionWindow();
static int  bufCreateImageBuffers();
static void bufDestroyImageBuffers();
static void bufDisplayImageBuffers();
static void bufClearImageBufferArea();
static void bufDestroyBuffer();
static void bufCopyBufferBits();
static void bufDrawSelectPlane();
static void bufWrapScreenFuncs();
static void bufResetProc();

static void bufPostValidateTree();
static void bufClipNotify();
static void bufWindowExposures();
static Bool bufChangeWindowAttributes();
static void bufClearToBackground();
static void bufCopyWindow();

extern WindowPtr *WindowTable;

static Bool
bufMultibufferInit(pScreen, pMBScreen)
    ScreenPtr pScreen;
    mbufScreenPtr pMBScreen;
{
    mbufBufferPrivPtr	pMBPriv;
    BoxRec		box;

    /* Multibuffer info */
    pMBScreen->nInfo = bufNumInfo[pScreen->myNum];
    pMBScreen->pInfo = bufInfo[pScreen->myNum];

    /* Hooks */
    pMBScreen->CreateImageBuffers = bufCreateImageBuffers;
    pMBScreen->DestroyImageBuffers = bufDestroyImageBuffers;
    pMBScreen->DisplayImageBuffers = bufDisplayImageBuffers;
    pMBScreen->ClearImageBufferArea = bufClearImageBufferArea;
    pMBScreen->ChangeMBufferAttributes = NoopDDA_True;
    pMBScreen->ChangeBufferAttributes = NoopDDA_True;
    pMBScreen->DeleteBufferDrawable = bufDestroyBuffer;
    pMBScreen->WrapScreenFuncs = bufWrapScreenFuncs;
    pMBScreen->ResetProc = bufResetProc;
    /* Create devPrivate part */
    pMBPriv = (mbufBufferPrivPtr) xalloc(sizeof *pMBPriv);
    if (!pMBPriv)
	return (FALSE);

    pMBScreen->devPrivate.ptr = (pointer) pMBPriv;
    pMBPriv->frameBuffer  = bufFrameBuffer[pScreen->myNum];
    pMBPriv->selectPlane = bufselectPlane[pScreen->myNum];

    /*
     * Initializing the subtractRgn to the screen area will ensure that
     * the selectPlane will get cleared on the first PostValidateTree.
     */

    box.x1 = 0;
    box.y1 = 0;
    box.x2 = pScreen->width;
    box.y2 = pScreen->height;

    pMBPriv->rgnChanged = TRUE;
    REGION_INIT(pScreen, &pMBPriv->backBuffer, &box, 1);
    REGION_INIT(pScreen, &pMBPriv->subtractRgn, &box, 1);
    REGION_INIT(pScreen, &pMBPriv->unionRgn, NullBox, 0);

    /* Misc functions */
    pMBPriv->CopyBufferBits  = bufCopyBufferBitsFunc[pScreen->myNum];
    pMBPriv->DrawSelectPlane = bufDrawSelectPlaneFunc[pScreen->myNum];

    if (!pMBPriv->CopyBufferBits)
	pMBPriv->CopyBufferBits = bufCopyBufferBits;

    if (!pMBPriv->DrawSelectPlane)
	pMBPriv->DrawSelectPlane = bufDrawSelectPlane;

    /* screen functions */
    pMBPriv->funcsWrapped = 0;
    pMBPriv->inClearToBackground = FALSE;
    pMBPriv->WindowExposures = NULL;
    pMBPriv->CopyWindow = NULL;
    pMBPriv->ClearToBackground = NULL;
    pMBPriv->ClipNotify = NULL;
    pMBPriv->ChangeWindowAttributes = NULL;

    /* Start out wrapped to clear select plane */
    WRAP_SCREEN_FUNC(pScreen,pMBPriv,PostValidateTree, bufPostValidateTree);
    return TRUE;
}

static void
UpdateBufferFromWindow(pBuffer, pWin)
    BufferPtr	pBuffer;
    WindowPtr	pWin;
{
    pBuffer->drawable.x      = pWin->drawable.x;
    pBuffer->drawable.y      = pWin->drawable.y;
    pBuffer->drawable.width  = pWin->drawable.width;
    pBuffer->drawable.height = pWin->drawable.height;

    pBuffer->drawable.serialNumber = NEXT_SERIAL_NUMBER;

    /* Update for PaintWindowBackground */
    pBuffer->parent = pWin->parent;

    /*
     * Make the borderClip the same as the clipList so
     * NotClippedByChildren comes out with just clipList.
     */

    pBuffer->clipList   = pWin->clipList;
    pBuffer->borderClip = pWin->clipList;
    pBuffer->winSize    = pWin->winSize;
    pBuffer->borderSize = pWin->borderSize;

    pBuffer->origin = pWin->origin;
}

static BufferPtr
bufCreateBuffer(pScreen, pWin, bufferNum)
    ScreenPtr	pScreen;
    WindowPtr	pWin;
    int		bufferNum;
{
    mbufBufferPrivPtr	pMBPriv;
    DevUnion	*devPrivates;
    BufferPtr	pBuffer;
    int		i;

    pMBPriv = MB_SCREEN_PRIV_BUFFER(pScreen);

    pBuffer = AllocateWindow(pWin->drawable.pScreen);
    if (!pBuffer)
	return (NULL);

    /* XXX- Until we know what is needed, copy everything. */
    devPrivates = pBuffer->devPrivates;
    *pBuffer = *pWin;
    pBuffer->devPrivates   = devPrivates;

    pBuffer->drawable.type = DRAWABLE_BUFFER;
    pBuffer->drawable.serialNumber = NEXT_SERIAL_NUMBER;

    pBuffer->nextSib    = NULL;
    pBuffer->prevSib    = NULL;
    pBuffer->firstChild = NULL;
    pBuffer->lastChild  = NULL;

    /* XXX - Worry about backingstore later */
    pBuffer->backStorage   = NULL;
    pBuffer->backingStore  = NotUseful;

    /* XXX - Need to call pScreen->CreateWindow for tile/stipples
     *       or should I just copy the devPrivates?
     */
    
    for (i=0; i < pScreen->WindowPrivateLen; i++)
	pBuffer->devPrivates[i] = pWin->devPrivates[i];

    pBuffer->devPrivates[frameWindowPrivateIndex] =
	pMBPriv->frameBuffer[bufferNum];

    return pBuffer;
}

static void
bufDestroyBuffer(pDrawable)
    DrawablePtr	pDrawable;
{