gdi.c

这是ARM嵌入式系统的实验教程中的MINIGUI的实验源代码！

// local clip region and global clip region.
// if the global clip region has a new age,
// this function empty effective clip region first,
// and then intersect local clip region and global clip region.

BOOL dc_GenerateECRgn(PDC pdc, BOOL fForce)
{
    RECT rc, rcInter;
    PCLIPRECT pcr, pgcr;
    PCONTROL pCtrl;

    // is global clip region is empty?
    if ((!fForce) && (!dc_IsVisible (pdc)))
            return FALSE;

    // need regenerate?
    if (fForce || (pdc->oldage != pdc->pGCRInfo->age)) {
        EmptyClipRgn (&pdc->ecrgn);

        pcr = pdc->lcrgn.head;
        while (pcr) {
            rc = pcr->rc;
            coor_LP2SP (pdc, &rc.left, &rc.top);
            coor_LP2SP (pdc, &rc.right, &rc.bottom);
            
            pgcr = pdc->pGCRInfo->crgn.head;
            while (pgcr) {

                if (IntersectRect (&rcInter, &rc, &pgcr->rc))
                    AddClipRect (&pdc->ecrgn, &rcInter);

                pgcr = pgcr->next;
            }
            
            pcr = pcr->next;
        }
        
        if (pdc->lcrgn.head == NULL)
            ClipRgnCopy (&pdc->ecrgn, &pdc->pGCRInfo->crgn);

        // update the DevRC;
        if (pdc->bIsClient)
            WndClientRect (pdc->hwnd, &pdc->DevRC);
        else
            WndRect (pdc->hwnd, &pdc->DevRC);
            
        IntersectClipRect (&pdc->ecrgn, &pdc->DevRC);

        pCtrl = Control (pdc->hwnd);
        if (pCtrl && !(pCtrl->dwExStyle & WS_EX_CTRLASMAINWIN))
            RestrictControlECRGN (&pdc->ecrgn, pCtrl);

        pdc->oldage = pdc->pGCRInfo->age;
    }

    return TRUE;
}

// This function init DC.
// set the default parameters.
static void dc_InitDC(PDC pdc, HWND hWnd, BOOL bIsClient)
{
    PCONTROL pCtrl;

    pdc->hwnd = hWnd;
    pdc->gc = PHYSICALGC;

    pdc->bkcolor = PIXEL_lightwhite;
    pdc->bkmode = 0;

    pdc->brushcolor = PIXEL_lightwhite;

    pdc->pencolor = PIXEL_black;
    pdc->CurPenPos.x = pdc->CurPenPos.y = 0;

    pdc->textcolor = PIXEL_black;
    if (!(pdc->pLogFont = GetWindowFont (hWnd)))
        pdc->pLogFont = GetSystemFont (SYSLOGFONT_WCHAR_DEF);
    pdc->tabstop = 8;
    pdc->CurTextPos.x = pdc->CurTextPos.y = 0;
    pdc->cExtra = pdc->alExtra = pdc->blExtra = 0;

    pdc->mapmode = MM_TEXT;
    pdc->ViewOrig.x = pdc->ViewOrig.y = 0;
    pdc->ViewExtent.x = pdc->ViewExtent.y = 1;
    pdc->WindowOrig.x = pdc->WindowOrig.y = 0;
    pdc->WindowExtent.x = pdc->WindowExtent.y = 1;

    // assume that the local clip region is empty.
  
    // Get global clip region info and generate effective clip region.
    pdc->pGCRInfo = GetGCRgnInfo (hWnd);

    pthread_mutex_lock (&pdc->pGCRInfo->lock);

    pdc->oldage = pdc->pGCRInfo->age;
    ClipRgnCopy (&pdc->ecrgn, &pdc->pGCRInfo->crgn);

    if (bIsClient)
        WndClientRect (pdc->hwnd, &pdc->DevRC);
    else
        WndRect (pdc->hwnd, &pdc->DevRC);

    pdc->bIsClient = bIsClient;
    if (bIsClient)
        IntersectClipRect (&pdc->ecrgn, &pdc->DevRC);

    pCtrl = Control (pdc->hwnd);
    if (pCtrl && !(pCtrl->dwExStyle & WS_EX_CTRLASMAINWIN))
        RestrictControlECRGN (&pdc->ecrgn, pCtrl);

    pthread_mutex_unlock (&pdc->pGCRInfo->lock);

}

static void dc_Init_ScreenDC (void)
{
    __mg_screen_dc.DataType = TYPE_HDC;
    __mg_screen_dc.DCType   = TYPE_SCRDC;
    __mg_screen_dc.hwnd = 0;
    __mg_screen_dc.gc = PHYSICALGC;

    __mg_screen_dc.bkcolor = PIXEL_lightwhite;
    __mg_screen_dc.bkmode = 0;

    __mg_screen_dc.brushcolor = PIXEL_lightwhite;
    __mg_screen_dc.pencolor = PIXEL_black;
    __mg_screen_dc.CurPenPos.x = __mg_screen_dc.CurPenPos.y = 0;

    __mg_screen_dc.textcolor = PIXEL_black;
    __mg_screen_dc.pLogFont = GetSystemFont (SYSLOGFONT_WCHAR_DEF);
    __mg_screen_dc.tabstop = 8;
    __mg_screen_dc.CurTextPos.x = __mg_screen_dc.CurTextPos.y = 0;
    __mg_screen_dc.cExtra = __mg_screen_dc.alExtra = __mg_screen_dc.blExtra = 0;

    __mg_screen_dc.ViewOrig.x = __mg_screen_dc.ViewOrig.y = 0;
    __mg_screen_dc.ViewExtent.x = __mg_screen_dc.ViewExtent.y = 1;
    __mg_screen_dc.WindowOrig.x = __mg_screen_dc.WindowOrig.y = 0;
    __mg_screen_dc.WindowExtent.x = __mg_screen_dc.WindowExtent.y = 1;

    __mg_screen_dc.bIsClient = FALSE;

    // init local clip region
    InitClipRgn (&__mg_screen_dc.lcrgn, &sg_FreeClipRectList);
    // init effective clip region
    InitClipRgn (&__mg_screen_dc.ecrgn, &sg_FreeClipRectList);

    // init global clip region information
    __mg_screen_dc.pGCRInfo = NULL;
    __mg_screen_dc.oldage = 0;

    __mg_screen_dc.DevRC.left = 0;
    __mg_screen_dc.DevRC.top  = 0;
    __mg_screen_dc.DevRC.right = WIDTHOFPHYGC - 1;
    __mg_screen_dc.DevRC.bottom = HEIGHTOFPHYGC - 1;

    // Set local clip region and effetive clip region to the screen.
    SetClipRgn (&__mg_screen_dc.lcrgn, &__mg_screen_dc.DevRC);
    SetClipRgn (&__mg_screen_dc.ecrgn, &__mg_screen_dc.DevRC);
}
        
/*
 * Function: HDC GUIAPI GetClientDC(HWND hWnd)
 *     This function get the specified window client's DC.
 * Parameter:
 *     HWND hWnd: The window, 0 for screen.
 * Return:
 *     The handle of wanted DC.
 */

HDC GUIAPI GetClientDC(HWND hWnd)
{
    int i;

    pthread_mutex_lock (&dcslot);
    for (i = 0; i < DCSLOTNUMBER; i++) {
        if (!DCSlot[i].inuse) {
            DCSlot[i].inuse = TRUE;
            DCSlot[i].DataType = TYPE_HDC;
            DCSlot[i].DCType   = TYPE_GENDC;
            break;
        }
    }
    pthread_mutex_unlock (&dcslot);

    if (i >= DCSLOTNUMBER)
        return HDC_SCREEN;

    dc_InitDC (DCSlot + i, hWnd, TRUE);
    return (HDC) (DCSlot + i);
}

/*
 * Function: HDC GUIAPI GetDC(HWND hWnd)
 *     This function get the specified window's DC.
 * Parameter:
 *     HWND hWnd: The window, 0 for screen.
 * Return:
 *     The handle of wanted DC.
 */

HDC GUIAPI GetDC(HWND hWnd)
{
    int i;

    // allocate an empty dc slot exclusively   
    pthread_mutex_lock (&dcslot);
    for(i = 0; i < DCSLOTNUMBER; i++) {
        if(!DCSlot[i].inuse) {
            DCSlot[i].inuse = TRUE;
            DCSlot[i].DataType = TYPE_HDC;
            DCSlot[i].DCType   = TYPE_GENDC;
            break;
        }
    }
    pthread_mutex_unlock(&dcslot);

    if (i >= DCSLOTNUMBER)
        return HDC_SCREEN;

    dc_InitDC(DCSlot + i, hWnd, FALSE);
    return (HDC)(DCSlot + i);
}

/*
 * Function: void GUIAPI ReleaseDC(HDC hDC)
 *     This function release the specified DC.
 * Parameter:
 *     HDC hDC: The DC handle want to release.
 * Return:
 *     None. 
 */
void GUIAPI ReleaseDC (HDC hDC)
{
    PMAINWIN pWin;
    PDC pdc;
    PCONTROL pCtrl;

    pdc = dc_HDC2PDC(hDC);

    EmptyClipRgn (&pdc->lcrgn);

    pWin = (PMAINWIN)(pdc->hwnd);
    if (pWin && pWin->privCDC == hDC) {
        /* for private DC, we reset the clip region info. */
        pthread_mutex_lock (&pdc->pGCRInfo->lock);

        pdc->oldage = pdc->pGCRInfo->age;
        ClipRgnCopy (&pdc->ecrgn, &pdc->pGCRInfo->crgn);

        if (pdc->bIsClient)
            WndClientRect (pdc->hwnd, &pdc->DevRC);
        else
            WndRect (pdc->hwnd, &pdc->DevRC);

        IntersectClipRect (&pdc->ecrgn, &pdc->DevRC);

        pCtrl = Control (pdc->hwnd);
        if (pCtrl && !(pCtrl->dwExStyle & WS_EX_CTRLASMAINWIN))
            RestrictControlECRGN (&pdc->ecrgn, pCtrl);

        pthread_mutex_unlock (&pdc->pGCRInfo->lock);
    }
    else {
        EmptyClipRgn (&pdc->ecrgn);
        pdc->pGCRInfo = NULL;
        pdc->oldage = 0;

        pthread_mutex_lock (&dcslot);
        pdc->inuse = FALSE;
        pthread_mutex_unlock(&dcslot);
    }

}

/*
 * Function: HDC GUIAPI CreateCompatibleDC (HDC hdc)
 *     This function create a memory dc, which is compatible 
 *     with specified hdc.
 * Parameters:
 *     HDC hdc: the specified DC handle.
 * Return:
 *     None.
 */
HDC GUIAPI CreateCompatibleDC(HDC hdc)
{
    GAL_GC gc;
    PDC pdc;
    PDC pMemDC = NULL;

    pdc = dc_HDC2PDC(hdc);

    if (!(pMemDC = malloc (sizeof(DC)))) return HDC_INVALID;
    pthread_mutex_lock (&__mg_gdilock);
    if (GAL_AllocateGC (pdc->gc, RECTW (pdc->DevRC), RECTH (pdc->DevRC), 
            GAL_BytesPerPixel (pdc->gc), &gc) != 0) {
        pthread_mutex_unlock (&__mg_gdilock);
        return HDC_INVALID;
    }
    pthread_mutex_unlock (&__mg_gdilock);

    memcpy (pMemDC, pdc, sizeof(DC));

    pMemDC->DataType = TYPE_HDC;
    pMemDC->DCType   = TYPE_MEMDC;
    pMemDC->inuse = TRUE;
    pMemDC->gc = gc;

    // clip region info
    InitClipRgn (&pMemDC->lcrgn, &sg_FreeClipRectList);
    InitClipRgn (&pMemDC->ecrgn, &sg_FreeClipRectList);
    pMemDC->pGCRInfo = NULL;
    pMemDC->oldage = 0;

    pMemDC->DevRC.left = 0;
    pMemDC->DevRC.top  = 0;
    pMemDC->DevRC.right = RECTW(pdc->DevRC);
    pMemDC->DevRC.bottom = RECTH(pdc->DevRC);

    SetClipRgn (&pMemDC->ecrgn, &pMemDC->DevRC);
    
    return (HDC)pMemDC;
}

/*
 *  Function: DeleteCompatibleDC (HDC hdc)
 *      This function delete the memory DC, and free the associated memory.
 *  Parameters:
 *      HDC hdc: the DC handle want to delete.
 *  Return:
 *      FALSE: the specified HDC is not a valid memory DC.
 *      TRUE:  deleted.
 */
void GUIAPI DeleteCompatibleDC(HDC hdc)
{
    PDC pMemDC;
    
    pMemDC = dc_HDC2PDC(hdc);

    // free gl resource
    GAL_FreeGC (pMemDC->gc);

    // free clip region info
    EmptyClipRgn (&pMemDC->lcrgn);
    EmptyClipRgn (&pMemDC->ecrgn);

    // free DC slot
    free (pMemDC);
}

HDC GUIAPI CreatePrivateDC(HWND hwnd)
{
    PDC pdc;

    if (!(pdc = malloc (sizeof(DC)))) return HDC_INVALID;

    InitClipRgn (&pdc->lcrgn, &sg_FreeClipRectList);
    InitClipRgn (&pdc->ecrgn, &sg_FreeClipRectList);
    
    pdc->inuse = TRUE;
    pdc->DataType = TYPE_HDC;
    pdc->DCType   = TYPE_GENDC;
    dc_InitDC(pdc, hwnd, FALSE);
    return (HDC)(pdc);
}

HDC GUIAPI CreatePrivateClientDC(HWND hwnd)
{
    PDC pdc;

    if (!(pdc = malloc (sizeof(DC)))) return HDC_INVALID;

    InitClipRgn (&pdc->lcrgn, &sg_FreeClipRectList);
    InitClipRgn (&pdc->ecrgn, &sg_FreeClipRectList);
    
    pdc->inuse = TRUE;
    pdc->DataType = TYPE_HDC;
    pdc->DCType   = TYPE_GENDC;
    dc_InitDC(pdc, hwnd, TRUE);
    return (HDC)(pdc);
}

void GUIAPI DeletePrivateDC(HDC hdc)
{
    PDC pdc;

    pdc = (PDC)hdc;
    
    EmptyClipRgn (&pdc->lcrgn);
    EmptyClipRgn (&pdc->ecrgn);

    free (pdc);
}

HDC GUIAPI GetPrivateClientDC (HWND hwnd)
{
    PMAINWIN pWin = (PMAINWIN)hwnd;

    return pWin->privCDC;
}