/* Copyright (C) 2002-2005 RealVNC Ltd.  All Rights Reserved. *  * This is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. *  * This software is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the * GNU General Public License for more details. *  * You should have received a copy of the GNU General Public License * along with this software; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, * USA. */#ifndef __REGIONHELPER_H__#define __REGIONHELPER_H__// RegionHelper is a class which helps in using X server regions by// automatically freeing them in the destructor.  It also fixes a problem with// REGION_INIT when given an empty rectangle.// REGION_NULL was introduced in the Xorg tree as the way to initialise an// empty region.  If it's not already defined do it the old way.  Note that the// old way causes a segfault in the new tree...#ifndef REGION_NULL#define REGION_NULL(pScreen,pReg) REGION_INIT(pScreen,pReg,NullBox,0)#endifclass RegionHelper {public:  // constructor from a single rect  RegionHelper(ScreenPtr pScreen_, BoxPtr rect, int size)    : pScreen(pScreen_), reg(0)  {    init(rect, size);  }  // constructor from an existing X server region  RegionHelper(ScreenPtr pScreen_, RegionPtr pRegion)    : pScreen(pScreen_), reg(&regRec)  {    REGION_NULL(pScreen, reg);    REGION_COPY(pScreen, reg, pRegion);  }  // constructor from an array of rectangles  RegionHelper(ScreenPtr pScreen_, int nrects, xRectanglePtr rects,               int ctype=CT_NONE)    : pScreen(pScreen_)  {    reg = RECTS_TO_REGION(pScreen, nrects, rects, ctype);  }  // constructor for calling init() later  RegionHelper(ScreenPtr pScreen_) : pScreen(pScreen_), reg(0) {  }  void init(BoxPtr rect, int size) {    reg = &regRec;    if (!rect || (rect && (rect->x2 == rect->x1 || rect->y2 == rect->y1))) {      REGION_NULL(pScreen, reg);    } else {      REGION_INIT(pScreen, reg, rect, size);    }  }  // destructor frees as appropriate  ~RegionHelper() {    if (reg == &regRec) {      REGION_UNINIT(pScreen, reg);    } else if (reg) {      REGION_DESTROY(pScreen, reg);    }  }  ScreenPtr pScreen;  RegionRec regRec;  RegionPtr reg;};#endif