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authorLars Knoll <lars.knoll@nokia.com>2009-03-23 09:18:55 (GMT)
committerSimon Hausmann <simon.hausmann@nokia.com>2009-03-23 09:18:55 (GMT)
commite5fcad302d86d316390c6b0f62759a067313e8a9 (patch)
treec2afbf6f1066b6ce261f14341cf6d310e5595bc1 /src/gui/painting/qregion_qws.cpp
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Long live Qt 4.5!
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+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the QtGui module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain
+** additional rights. These rights are described in the Nokia Qt LGPL
+** Exception version 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+// XXX - add appropriate friendship relationships
+#define private public
+#include "qregion.h"
+#undef private
+#include "qpainterpath.h"
+#include "qpolygon.h"
+#include "qbuffer.h"
+#include "qimage.h"
+#include <qdebug.h>
+#include "qbitmap.h"
+#include <stdlib.h>
+#include <qatomic.h>
+#include <qsemaphore.h>
+
+QT_BEGIN_NAMESPACE
+
+class QFastMutex
+{
+ QAtomicInt contenders;
+ QSemaphore semaphore;
+public:
+ inline QFastMutex()
+ : contenders(0), semaphore(0)
+ { }
+ inline void lock()
+ {
+ if (contenders.fetchAndAddAcquire(1) != 0) {
+ semaphore.acquire();
+ contenders.deref();
+ }
+ }
+ inline bool tryLock()
+ {
+ return contenders.testAndSetAcquire(0, 1);
+ }
+ inline void unlock()
+ {
+ if (!contenders.testAndSetRelease(1, 0))
+ semaphore.release();
+ }
+};
+
+
+/*
+ * 1 if r1 contains r2
+ * 0 if r1 does not completely contain r2
+ */
+#define CONTAINSCHECK(r1, r2) \
+ ((r2).left() >= (r1).left() && (r2).right() <= (r1).right() && \
+ (r2).top() >= (r1).top() && (r2).bottom() <= (r1).bottom())
+
+/*
+ * clip region
+ */
+struct QRegionPrivate : public QRegion::QRegionData {
+ enum { Single, Vector } mode;
+ int numRects;
+ QVector<QRect> rects;
+ QRect single;
+ QRect extents;
+ QRect innerRect;
+ union {
+ int innerArea;
+ QRegionPrivate *next;
+ };
+
+ inline void vector()
+ {
+ if(mode != Vector && numRects) {
+ if(rects.size() < 1) rects.resize(1);
+ rects[0] = single;
+ }
+ mode = Vector;
+ }
+
+ inline QRegionPrivate() : mode(Single), numRects(0), innerArea(-1) {}
+ inline QRegionPrivate(const QRect &r) : mode(Single) {
+ numRects = 1;
+// rects[0] = r;
+ single = r;
+ extents = r;
+ innerRect = r;
+ innerArea = r.width() * r.height();
+ }
+
+ inline QRegionPrivate(const QRegionPrivate &r) {
+ mode = r.mode;
+ rects = r.rects;
+ single = r.single;
+ numRects = r.numRects;
+ extents = r.extents;
+ innerRect = r.innerRect;
+ innerArea = r.innerArea;
+ }
+
+ inline QRegionPrivate &operator=(const QRegionPrivate &r) {
+ mode = r.mode;
+ rects = r.rects;
+ single = r.single;
+ numRects = r.numRects;
+ extents = r.extents;
+ innerRect = r.innerRect;
+ innerArea = r.innerArea;
+ return *this;
+ }
+
+ /*
+ * Returns true if r is guaranteed to be fully contained in this region.
+ * A false return value does not guarantee the opposite.
+ */
+ inline bool contains(const QRegionPrivate &r) const {
+ const QRect &r1 = innerRect;
+ const QRect &r2 = r.extents;
+ return CONTAINSCHECK(r1, r2);
+ }
+
+ inline void updateInnerRect(const QRect &rect) {
+ const int area = rect.width() * rect.height();
+ if (area > innerArea) {
+ innerArea = area;
+ innerRect = rect;
+ }
+ }
+
+ void append(const QRegionPrivate *r);
+ void prepend(const QRegionPrivate *r);
+ inline bool canAppend(const QRegionPrivate *r) const;
+ inline bool canPrepend(const QRegionPrivate *r) const;
+};
+
+static QRegionPrivate *qt_nextRegionPtr = 0;
+static QFastMutex qt_nextRegionLock;
+
+static QRegionPrivate *qt_allocRegionMemory()
+{
+ QRegionPrivate *rv = 0;
+ qt_nextRegionLock.lock();
+
+ if(qt_nextRegionPtr) {
+ rv = qt_nextRegionPtr;
+ qt_nextRegionPtr = rv->next;
+ } else {
+ qt_nextRegionPtr =
+ (QRegionPrivate *)malloc(256 * sizeof(QRegionPrivate));
+ for(int ii = 0; ii < 256; ++ii) {
+ if(ii == 255) {
+ qt_nextRegionPtr[ii].next = 0;
+ } else {
+ qt_nextRegionPtr[ii].next = &qt_nextRegionPtr[ii + 1];
+ }
+ }
+
+ rv = qt_nextRegionPtr;
+ qt_nextRegionPtr = rv->next;
+ }
+
+ qt_nextRegionLock.unlock();
+ return rv;
+}
+
+static void qt_freeRegionMemory(QRegionPrivate *rp)
+{
+ qt_nextRegionLock.lock();
+ rp->next = qt_nextRegionPtr;
+ qt_nextRegionPtr = rp;
+ qt_nextRegionLock.unlock();
+}
+
+static QRegionPrivate *qt_allocRegion()
+{
+ QRegionPrivate *mem = qt_allocRegionMemory();
+ return new (mem) QRegionPrivate;
+}
+
+static QRegionPrivate *qt_allocRegion(const QRect &r)
+{
+ QRegionPrivate *mem = qt_allocRegionMemory();
+ return new (mem) QRegionPrivate(r);
+}
+
+static QRegionPrivate *qt_allocRegion(const QRegionPrivate &r)
+{
+ QRegionPrivate *mem = qt_allocRegionMemory();
+ return new (mem) QRegionPrivate(r);
+}
+
+void qt_freeRegion(QRegionPrivate *rp)
+{
+ rp->~QRegionPrivate();
+ qt_freeRegionMemory(rp);
+// delete rp;
+}
+
+static inline bool isEmptyHelper(const QRegionPrivate *preg)
+{
+ return !preg || preg->numRects == 0;
+}
+
+void QRegionPrivate::append(const QRegionPrivate *r)
+{
+ Q_ASSERT(!isEmptyHelper(r));
+
+ vector();
+ QRect *destRect = rects.data() + numRects;
+ const QRect *srcRect = (r->mode==Vector)?r->rects.constData():&r->single;
+ int numAppend = r->numRects;
+
+ // test for merge in x direction
+ {
+ const QRect *rFirst = srcRect;
+ QRect *myLast = rects.data() + (numRects - 1);
+ if (rFirst->top() == myLast->top()
+ && rFirst->height() == myLast->height()
+ && rFirst->left() == (myLast->right() + 1))
+ {
+ myLast->setWidth(myLast->width() + rFirst->width());
+ updateInnerRect(*myLast);
+ ++srcRect;
+ --numAppend;
+ }
+ }
+
+ // append rectangles
+ const int newNumRects = numRects + numAppend;
+ if (newNumRects > rects.size()) {
+ rects.resize(newNumRects);
+ destRect = rects.data() + numRects;
+ }
+ memcpy(destRect, srcRect, numAppend * sizeof(QRect));
+
+ // update inner rectangle
+ if (innerArea < r->innerArea) {
+ innerArea = r->innerArea;
+ innerRect = r->innerRect;
+ }
+
+ // update extents
+ destRect = &extents;
+ srcRect = &r->extents;
+ extents.setCoords(qMin(destRect->left(), srcRect->left()),
+ qMin(destRect->top(), srcRect->top()),
+ qMax(destRect->right(), srcRect->right()),
+ qMax(destRect->bottom(), srcRect->bottom()));
+
+ numRects = newNumRects;
+}
+
+void QRegionPrivate::prepend(const QRegionPrivate *r)
+{
+#if 1
+ Q_UNUSED(r);
+#else
+ // XXX ak: does not respect vectorization of region
+
+ Q_ASSERT(!isEmpty(r));
+
+ // move existing rectangles
+ memmove(rects.data() + r->numRects, rects.constData(),
+ numRects * sizeof(QRect));
+
+ // prepend new rectangles
+ memcpy(rects.data(), r->rects.constData(), r->numRects * sizeof(QRect));
+
+ // update inner rectangle
+ if (innerArea < r->innerArea) {
+ innerArea = r->innerArea;
+ innerRect = r->innerRect;
+ }
+
+ // update extents
+ destRect = &extents;
+ srcRect = &r->extents;
+ extents.setCoords(qMin(destRect->left(), srcRect->left()),
+ qMin(destRect->top(), srcRect->top()),
+ qMax(destRect->right(), srcRect->right()),
+ qMax(destRect->bottom(), srcRect->bottom()));
+
+ numRects = newNumRects;
+#endif
+}
+
+bool QRegionPrivate::canAppend(const QRegionPrivate *r) const
+{
+ Q_ASSERT(!isEmptyHelper(r));
+
+ const QRect *rFirst = (r->mode==Vector)?r->rects.constData():&r->single;
+ const QRect *myLast = (mode==Vector)?(rects.constData() + (numRects - 1)):&single;
+ // XXX: possible improvements:
+ // - nFirst->top() == myLast->bottom() + 1, must possibly merge bands
+ if (rFirst->top() > (myLast->bottom() + 1)
+ || (rFirst->top() == myLast->top()
+ && rFirst->height() == myLast->height()
+ && rFirst->left() > myLast->right()))
+ {
+ return true;
+ }
+
+ return false;
+}
+
+bool QRegionPrivate::canPrepend(const QRegionPrivate *r) const
+{
+#if 1
+ Q_UNUSED(r);
+ return false;
+#else
+ return r->canAppend(this);
+#endif
+}
+
+#if defined(Q_WS_X11)
+QT_BEGIN_INCLUDE_NAMESPACE
+# include "qregion_x11.cpp"
+QT_END_INCLUDE_NAMESPACE
+#elif defined(Q_WS_MAC)
+QT_BEGIN_INCLUDE_NAMESPACE
+# include "qregion_mac.cpp"
+QT_END_INCLUDE_NAMESPACE
+#elif defined(Q_WS_QWS)
+static QRegionPrivate qrp;
+QRegion::QRegionData QRegion::shared_empty = {Q_BASIC_ATOMIC_INITIALIZER(1), &qrp};
+#endif
+
+typedef void (*OverlapFunc)(register QRegionPrivate &dest, register const QRect *r1, const QRect *r1End,
+ register const QRect *r2, const QRect *r2End, register int y1, register int y2);
+typedef void (*NonOverlapFunc)(register QRegionPrivate &dest, register const QRect *r, const QRect *rEnd,
+ register int y1, register int y2);
+
+static bool EqualRegion(const QRegionPrivate *r1, const QRegionPrivate *r2);
+static void UnionRegion(const QRegionPrivate *reg1, const QRegionPrivate *reg2, QRegionPrivate &dest);
+static void miRegionOp(register QRegionPrivate &dest, const QRegionPrivate *reg1, const QRegionPrivate *reg2,
+ OverlapFunc overlapFunc, NonOverlapFunc nonOverlap1Func,
+ NonOverlapFunc nonOverlap2Func);
+
+#define RectangleOut 0
+#define RectangleIn 1
+#define RectanglePart 2
+#define EvenOddRule 0
+#define WindingRule 1
+
+// START OF region.h extract
+/* $XConsortium: region.h,v 11.14 94/04/17 20:22:20 rws Exp $ */
+/************************************************************************
+
+Copyright (c) 1987 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.
+
+
+Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts.
+
+ All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the name of Digital not be
+used in advertising or publicity pertaining to distribution of the
+software without specific, written prior permission.
+
+DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
+ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
+DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
+ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+SOFTWARE.
+
+************************************************************************/
+
+#ifndef _XREGION_H
+#define _XREGION_H
+
+QT_BEGIN_INCLUDE_NAMESPACE
+#include <limits.h>
+QT_END_INCLUDE_NAMESPACE
+
+/* 1 if two BOXs overlap.
+ * 0 if two BOXs do not overlap.
+ * Remember, x2 and y2 are not in the region
+ */
+#define EXTENTCHECK(r1, r2) \
+ ((r1)->right() >= (r2)->left() && \
+ (r1)->left() <= (r2)->right() && \
+ (r1)->bottom() >= (r2)->top() && \
+ (r1)->top() <= (r2)->bottom())
+
+/*
+ * update region extents
+ */
+#define EXTENTS(r,idRect){\
+ if((r)->left() < (idRect)->extents.left())\
+ (idRect)->extents.setLeft((r)->left());\
+ if((r)->top() < (idRect)->extents.top())\
+ (idRect)->extents.setTop((r)->top());\
+ if((r)->right() > (idRect)->extents.right())\
+ (idRect)->extents.setRight((r)->right());\
+ if((r)->bottom() > (idRect)->extents.bottom())\
+ (idRect)->extents.setBottom((r)->bottom());\
+ }
+
+/*
+ * Check to see if there is enough memory in the present region.
+ */
+#define MEMCHECK(dest, rect, firstrect){\
+ if ((dest).numRects >= ((dest).rects.size()-1)){\
+ firstrect.resize(firstrect.size() * 2); \
+ (rect) = (firstrect).data() + (dest).numRects;\
+ }\
+ }
+
+
+/*
+ * number of points to buffer before sending them off
+ * to scanlines(): Must be an even number
+ */
+#define NUMPTSTOBUFFER 200
+
+/*
+ * used to allocate buffers for points and link
+ * the buffers together
+ */
+typedef struct _POINTBLOCK {
+ QPoint pts[NUMPTSTOBUFFER];
+ struct _POINTBLOCK *next;
+} POINTBLOCK;
+
+#endif
+// END OF region.h extract
+
+// START OF Region.c extract
+/* $XConsortium: Region.c /main/30 1996/10/22 14:21:24 kaleb $ */
+/************************************************************************
+
+Copyright (c) 1987, 1988 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.
+
+
+Copyright 1987, 1988 by Digital Equipment Corporation, Maynard, Massachusetts.
+
+ All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the name of Digital not be
+used in advertising or publicity pertaining to distribution of the
+software without specific, written prior permission.
+
+DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
+ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
+DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
+ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+SOFTWARE.
+
+************************************************************************/
+/*
+ * The functions in this file implement the Region abstraction, similar to one
+ * used in the X11 sample server. A Region is simply an area, as the name
+ * implies, and is implemented as a "y-x-banded" array of rectangles. To
+ * explain: Each Region is made up of a certain number of rectangles sorted
+ * by y coordinate first, and then by x coordinate.
+ *
+ * Furthermore, the rectangles are banded such that every rectangle with a
+ * given upper-left y coordinate (y1) will have the same lower-right y
+ * coordinate (y2) and vice versa. If a rectangle has scanlines in a band, it
+ * will span the entire vertical distance of the band. This means that some
+ * areas that could be merged into a taller rectangle will be represented as
+ * several shorter rectangles to account for shorter rectangles to its left
+ * or right but within its "vertical scope".
+ *
+ * An added constraint on the rectangles is that they must cover as much
+ * horizontal area as possible. E.g. no two rectangles in a band are allowed
+ * to touch.
+ *
+ * Whenever possible, bands will be merged together to cover a greater vertical
+ * distance (and thus reduce the number of rectangles). Two bands can be merged
+ * only if the bottom of one touches the top of the other and they have
+ * rectangles in the same places (of the same width, of course). This maintains
+ * the y-x-banding that's so nice to have...
+ */
+/* $XFree86: xc/lib/X11/Region.c,v 1.1.1.2.2.2 1998/10/04 15:22:50 hohndel Exp $ */
+
+static void UnionRectWithRegion(register const QRect *rect, const QRegionPrivate *source,
+ QRegionPrivate &dest)
+{
+ if (!rect->width() || !rect->height())
+ return;
+
+ QRegionPrivate region(*rect);
+
+ Q_ASSERT(EqualRegion(source, &dest));
+ Q_ASSERT(!isEmptyHelper(&region));
+
+ if (dest.numRects == 0)
+ dest = region;
+ else if (dest.canAppend(&region))
+ dest.append(&region);
+ else
+ UnionRegion(&region, source, dest);
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * miSetExtents --
+ * Reset the extents and innerRect of a region to what they should be.
+ * Called by miSubtract and miIntersect b/c they can't figure it out
+ * along the way or do so easily, as miUnion can.
+ *
+ * Results:
+ * None.
+ *
+ * Side Effects:
+ * The region's 'extents' and 'innerRect' structure is overwritten.
+ *
+ *-----------------------------------------------------------------------
+ */
+static void miSetExtents(QRegionPrivate &dest)
+{
+ register const QRect *pBox,
+ *pBoxEnd;
+ register QRect *pExtents;
+
+ dest.innerRect.setCoords(0, 0, -1, -1);
+ dest.innerArea = -1;
+ if (dest.numRects == 0) {
+ dest.extents.setCoords(0, 0, 0, 0);
+ return;
+ }
+
+ pExtents = &dest.extents;
+ pBox = (dest.mode==QRegionPrivate::Vector)?(dest.rects.constData()):(&dest.single);
+ pBoxEnd = (dest.mode==QRegionPrivate::Vector)?(&pBox[dest.numRects - 1]):(&dest.single);
+
+ /*
+ * Since pBox is the first rectangle in the region, it must have the
+ * smallest y1 and since pBoxEnd is the last rectangle in the region,
+ * it must have the largest y2, because of banding. Initialize x1 and
+ * x2 from pBox and pBoxEnd, resp., as good things to initialize them
+ * to...
+ */
+ pExtents->setLeft(pBox->left());
+ pExtents->setTop(pBox->top());
+ pExtents->setRight(pBoxEnd->right());
+ pExtents->setBottom(pBoxEnd->bottom());
+
+ Q_ASSERT(pExtents->top() <= pExtents->bottom());
+ while (pBox <= pBoxEnd) {
+ if (pBox->left() < pExtents->left())
+ pExtents->setLeft(pBox->left());
+ if (pBox->right() > pExtents->right())
+ pExtents->setRight(pBox->right());
+ dest.updateInnerRect(*pBox);
+ ++pBox;
+ }
+ Q_ASSERT(pExtents->left() <= pExtents->right());
+}
+
+/* TranslateRegion(pRegion, x, y)
+ translates in place
+ added by raymond
+*/
+
+static void OffsetRegion(register QRegionPrivate &region, register int x, register int y)
+{
+ register int nbox;
+ register QRect *pbox;
+
+ if(region.mode == QRegionPrivate::Single) {
+ region.single.translate(x, y);
+ } else {
+ pbox = region.rects.data();
+ nbox = region.numRects;
+
+ while (nbox--) {
+ pbox->translate(x, y);
+ ++pbox;
+ }
+ }
+ region.extents.translate(x, y);
+ region.innerRect.translate(x, y);
+}
+
+/*======================================================================
+ * Region Intersection
+ *====================================================================*/
+/*-
+ *-----------------------------------------------------------------------
+ * miIntersectO --
+ * Handle an overlapping band for miIntersect.
+ *
+ * Results:
+ * None.
+ *
+ * Side Effects:
+ * Rectangles may be added to the region.
+ *
+ *-----------------------------------------------------------------------
+ */
+static void miIntersectO(register QRegionPrivate &dest, register const QRect *r1, const QRect *r1End,
+ register const QRect *r2, const QRect *r2End, int y1, int y2)
+{
+ register int x1;
+ register int x2;
+ register QRect *pNextRect;
+
+ pNextRect = dest.rects.data() + dest.numRects;
+
+ while (r1 != r1End && r2 != r2End) {
+ x1 = qMax(r1->left(), r2->left());
+ x2 = qMin(r1->right(), r2->right());
+
+ /*
+ * If there's any overlap between the two rectangles, add that
+ * overlap to the new region.
+ * There's no need to check for subsumption because the only way
+ * such a need could arise is if some region has two rectangles
+ * right next to each other. Since that should never happen...
+ */
+ if (x1 <= x2) {
+ Q_ASSERT(y1 <= y2);
+ MEMCHECK(dest, pNextRect, dest.rects)
+ pNextRect->setCoords(x1, y1, x2, y2);
+ ++dest.numRects;
+ ++pNextRect;
+ }
+
+ /*
+ * Need to advance the pointers. Shift the one that extends
+ * to the right the least, since the other still has a chance to
+ * overlap with that region's next rectangle, if you see what I mean.
+ */
+ if (r1->right() < r2->right()) {
+ ++r1;
+ } else if (r2->right() < r1->right()) {
+ ++r2;
+ } else {
+ ++r1;
+ ++r2;
+ }
+ }
+}
+
+/*======================================================================
+ * Generic Region Operator
+ *====================================================================*/
+
+/*-
+ *-----------------------------------------------------------------------
+ * miCoalesce --
+ * Attempt to merge the boxes in the current band with those in the
+ * previous one. Used only by miRegionOp.
+ *
+ * Results:
+ * The new index for the previous band.
+ *
+ * Side Effects:
+ * If coalescing takes place:
+ * - rectangles in the previous band will have their y2 fields
+ * altered.
+ * - dest.numRects will be decreased.
+ *
+ *-----------------------------------------------------------------------
+ */
+static int miCoalesce(register QRegionPrivate &dest, int prevStart, int curStart)
+{
+ register QRect *pPrevBox; /* Current box in previous band */
+ register QRect *pCurBox; /* Current box in current band */
+ register QRect *pRegEnd; /* End of region */
+ int curNumRects; /* Number of rectangles in current band */
+ int prevNumRects; /* Number of rectangles in previous band */
+ int bandY1; /* Y1 coordinate for current band */
+ QRect *rData = dest.rects.data();
+
+ pRegEnd = rData + dest.numRects;
+
+ pPrevBox = rData + prevStart;
+ prevNumRects = curStart - prevStart;
+
+ /*
+ * Figure out how many rectangles are in the current band. Have to do
+ * this because multiple bands could have been added in miRegionOp
+ * at the end when one region has been exhausted.
+ */
+ pCurBox = rData + curStart;
+ bandY1 = pCurBox->top();
+ for (curNumRects = 0; pCurBox != pRegEnd && pCurBox->top() == bandY1; ++curNumRects) {
+ ++pCurBox;
+ }
+
+ if (pCurBox != pRegEnd) {
+ /*
+ * If more than one band was added, we have to find the start
+ * of the last band added so the next coalescing job can start
+ * at the right place... (given when multiple bands are added,
+ * this may be pointless -- see above).
+ */
+ --pRegEnd;
+ while ((pRegEnd - 1)->top() == pRegEnd->top())
+ --pRegEnd;
+ curStart = pRegEnd - rData;
+ pRegEnd = rData + dest.numRects;
+ }
+
+ if (curNumRects == prevNumRects && curNumRects != 0) {
+ pCurBox -= curNumRects;
+ /*
+ * The bands may only be coalesced if the bottom of the previous
+ * matches the top scanline of the current.
+ */
+ if (pPrevBox->bottom() == pCurBox->top() - 1) {
+ /*
+ * Make sure the bands have boxes in the same places. This
+ * assumes that boxes have been added in such a way that they
+ * cover the most area possible. I.e. two boxes in a band must
+ * have some horizontal space between them.
+ */
+ do {
+ if (pPrevBox->left() != pCurBox->left() || pPrevBox->right() != pCurBox->right()) {
+ // The bands don't line up so they can't be coalesced.
+ return curStart;
+ }
+ ++pPrevBox;
+ ++pCurBox;
+ --prevNumRects;
+ } while (prevNumRects != 0);
+
+ dest.numRects -= curNumRects;
+ pCurBox -= curNumRects;
+ pPrevBox -= curNumRects;
+
+ /*
+ * The bands may be merged, so set the bottom y of each box
+ * in the previous band to that of the corresponding box in
+ * the current band.
+ */
+ do {
+ pPrevBox->setBottom(pCurBox->bottom());
+ dest.updateInnerRect(*pPrevBox);
+ ++pPrevBox;
+ ++pCurBox;
+ curNumRects -= 1;
+ } while (curNumRects != 0);
+
+ /*
+ * If only one band was added to the region, we have to backup
+ * curStart to the start of the previous band.
+ *
+ * If more than one band was added to the region, copy the
+ * other bands down. The assumption here is that the other bands
+ * came from the same region as the current one and no further
+ * coalescing can be done on them since it's all been done
+ * already... curStart is already in the right place.
+ */
+ if (pCurBox == pRegEnd) {
+ curStart = prevStart;
+ } else {
+ do {
+ *pPrevBox++ = *pCurBox++;
+ dest.updateInnerRect(*pPrevBox);
+ } while (pCurBox != pRegEnd);
+ }
+ }
+ }
+ return curStart;
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * miRegionOp --
+ * Apply an operation to two regions. Called by miUnion, miInverse,
+ * miSubtract, miIntersect...
+ *
+ * Results:
+ * None.
+ *
+ * Side Effects:
+ * The new region is overwritten.
+ *
+ * Notes:
+ * The idea behind this function is to view the two regions as sets.
+ * Together they cover a rectangle of area that this function divides
+ * into horizontal bands where points are covered only by one region
+ * or by both. For the first case, the nonOverlapFunc is called with
+ * each the band and the band's upper and lower extents. For the
+ * second, the overlapFunc is called to process the entire band. It
+ * is responsible for clipping the rectangles in the band, though
+ * this function provides the boundaries.
+ * At the end of each band, the new region is coalesced, if possible,
+ * to reduce the number of rectangles in the region.
+ *
+ *-----------------------------------------------------------------------
+ */
+static void miRegionOp(register QRegionPrivate &dest, const QRegionPrivate *reg1, const QRegionPrivate *reg2,
+ OverlapFunc overlapFunc, NonOverlapFunc nonOverlap1Func,
+ NonOverlapFunc nonOverlap2Func)
+{
+ register const QRect *r1; // Pointer into first region
+ register const QRect *r2; // Pointer into 2d region
+ const QRect *r1End; // End of 1st region
+ const QRect *r2End; // End of 2d region
+ register int ybot; // Bottom of intersection
+ register int ytop; // Top of intersection
+ int prevBand; // Index of start of previous band in dest
+ int curBand; // Index of start of current band in dest
+ register const QRect *r1BandEnd; // End of current band in r1
+ register const QRect *r2BandEnd; // End of current band in r2
+ int top; // Top of non-overlapping band
+ int bot; // Bottom of non-overlapping band
+
+ /*
+ * Initialization:
+ * set r1, r2, r1End and r2End appropriately, preserve the important
+ * parts of the destination region until the end in case it's one of
+ * the two source regions, then mark the "new" region empty, allocating
+ * another array of rectangles for it to use.
+ */
+ r1 = (reg1->mode==QRegionPrivate::Vector)?reg1->rects.data():&reg1->single;
+ r2 = (reg2->mode==QRegionPrivate::Vector)?reg2->rects.data():&reg2->single;
+ r1End = r1 + reg1->numRects;
+ r2End = r2 + reg2->numRects;
+
+ dest.vector();
+ QVector<QRect> oldRects = dest.rects;
+
+ dest.numRects = 0;
+
+ /*
+ * Allocate a reasonable number of rectangles for the new region. The idea
+ * is to allocate enough so the individual functions don't need to
+ * reallocate and copy the array, which is time consuming, yet we don't
+ * have to worry about using too much memory. I hope to be able to
+ * nuke the realloc() at the end of this function eventually.
+ */
+ dest.rects.resize(qMax(reg1->numRects,reg2->numRects) * 2);
+
+ /*
+ * Initialize ybot and ytop.
+ * In the upcoming loop, ybot and ytop serve different functions depending
+ * on whether the band being handled is an overlapping or non-overlapping
+ * band.
+ * In the case of a non-overlapping band (only one of the regions
+ * has points in the band), ybot is the bottom of the most recent
+ * intersection and thus clips the top of the rectangles in that band.
+ * ytop is the top of the next intersection between the two regions and
+ * serves to clip the bottom of the rectangles in the current band.
+ * For an overlapping band (where the two regions intersect), ytop clips
+ * the top of the rectangles of both regions and ybot clips the bottoms.
+ */
+ if (reg1->extents.top() < reg2->extents.top())
+ ybot = reg1->extents.top() - 1;
+ else
+ ybot = reg2->extents.top() - 1;
+
+ /*
+ * prevBand serves to mark the start of the previous band so rectangles
+ * can be coalesced into larger rectangles. qv. miCoalesce, above.
+ * In the beginning, there is no previous band, so prevBand == curBand
+ * (curBand is set later on, of course, but the first band will always
+ * start at index 0). prevBand and curBand must be indices because of
+ * the possible expansion, and resultant moving, of the new region's
+ * array of rectangles.
+ */
+ prevBand = 0;
+
+ do {
+ curBand = dest.numRects;
+
+ /*
+ * This algorithm proceeds one source-band (as opposed to a
+ * destination band, which is determined by where the two regions
+ * intersect) at a time. r1BandEnd and r2BandEnd serve to mark the
+ * rectangle after the last one in the current band for their
+ * respective regions.
+ */
+ r1BandEnd = r1;
+ while (r1BandEnd != r1End && r1BandEnd->top() == r1->top())
+ ++r1BandEnd;
+
+ r2BandEnd = r2;
+ while (r2BandEnd != r2End && r2BandEnd->top() == r2->top())
+ ++r2BandEnd;
+
+ /*
+ * First handle the band that doesn't intersect, if any.
+ *
+ * Note that attention is restricted to one band in the
+ * non-intersecting region at once, so if a region has n
+ * bands between the current position and the next place it overlaps
+ * the other, this entire loop will be passed through n times.
+ */
+ if (r1->top() < r2->top()) {
+ top = qMax(r1->top(), ybot + 1);
+ bot = qMin(r1->bottom(), r2->top() - 1);
+
+ if (nonOverlap1Func != 0 && bot >= top)
+ (*nonOverlap1Func)(dest, r1, r1BandEnd, top, bot);
+ ytop = r2->top();
+ } else if (r2->top() < r1->top()) {
+ top = qMax(r2->top(), ybot + 1);
+ bot = qMin(r2->bottom(), r1->top() - 1);
+
+ if (nonOverlap2Func != 0 && bot >= top)
+ (*nonOverlap2Func)(dest, r2, r2BandEnd, top, bot);
+ ytop = r1->top();
+ } else {
+ ytop = r1->top();
+ }
+
+ /*
+ * If any rectangles got added to the region, try and coalesce them
+ * with rectangles from the previous band. Note we could just do
+ * this test in miCoalesce, but some machines incur a not
+ * inconsiderable cost for function calls, so...
+ */
+ if (dest.numRects != curBand)
+ prevBand = miCoalesce(dest, prevBand, curBand);
+
+ /*
+ * Now see if we've hit an intersecting band. The two bands only
+ * intersect if ybot >= ytop
+ */
+ ybot = qMin(r1->bottom(), r2->bottom());
+ curBand = dest.numRects;
+ if (ybot >= ytop)
+ (*overlapFunc)(dest, r1, r1BandEnd, r2, r2BandEnd, ytop, ybot);
+
+ if (dest.numRects != curBand)
+ prevBand = miCoalesce(dest, prevBand, curBand);
+
+ /*
+ * If we've finished with a band (y2 == ybot) we skip forward
+ * in the region to the next band.
+ */
+ if (r1->bottom() == ybot)
+ r1 = r1BandEnd;
+ if (r2->bottom() == ybot)
+ r2 = r2BandEnd;
+ } while (r1 != r1End && r2 != r2End);
+
+ /*
+ * Deal with whichever region still has rectangles left.
+ */
+ curBand = dest.numRects;
+ if (r1 != r1End) {
+ if (nonOverlap1Func != 0) {
+ do {
+ r1BandEnd = r1;
+ while (r1BandEnd < r1End && r1BandEnd->top() == r1->top())
+ ++r1BandEnd;
+ (*nonOverlap1Func)(dest, r1, r1BandEnd, qMax(r1->top(), ybot + 1), r1->bottom());
+ r1 = r1BandEnd;
+ } while (r1 != r1End);
+ }
+ } else if ((r2 != r2End) && (nonOverlap2Func != 0)) {
+ do {
+ r2BandEnd = r2;
+ while (r2BandEnd < r2End && r2BandEnd->top() == r2->top())
+ ++r2BandEnd;
+ (*nonOverlap2Func)(dest, r2, r2BandEnd, qMax(r2->top(), ybot + 1), r2->bottom());
+ r2 = r2BandEnd;
+ } while (r2 != r2End);
+ }
+
+ if (dest.numRects != curBand)
+ (void)miCoalesce(dest, prevBand, curBand);
+
+ /*
+ * A bit of cleanup. To keep regions from growing without bound,
+ * we shrink the array of rectangles to match the new number of
+ * rectangles in the region.
+ *
+ * Only do this stuff if the number of rectangles allocated is more than
+ * twice the number of rectangles in the region (a simple optimization).
+ */
+ if (qMax(4, dest.numRects) < (dest.rects.size() >> 1))
+ dest.rects.resize(dest.numRects);
+}
+
+/*======================================================================
+ * Region Union
+ *====================================================================*/
+
+/*-
+ *-----------------------------------------------------------------------
+ * miUnionNonO --
+ * Handle a non-overlapping band for the union operation. Just
+ * Adds the rectangles into the region. Doesn't have to check for
+ * subsumption or anything.
+ *
+ * Results:
+ * None.
+ *
+ * Side Effects:
+ * dest.numRects is incremented and the final rectangles overwritten
+ * with the rectangles we're passed.
+ *
+ *-----------------------------------------------------------------------
+ */
+
+static void miUnionNonO(register QRegionPrivate &dest, register const QRect *r, const QRect *rEnd,
+ register int y1, register int y2)
+{
+ register QRect *pNextRect;
+
+ pNextRect = dest.rects.data() + dest.numRects;
+
+ Q_ASSERT(y1 <= y2);
+
+ while (r != rEnd) {
+ Q_ASSERT(r->left() <= r->right());
+ MEMCHECK(dest, pNextRect, dest.rects)
+ pNextRect->setCoords(r->left(), y1, r->right(), y2);
+ dest.numRects++;
+ ++pNextRect;
+ ++r;
+ }
+}
+
+
+/*-
+ *-----------------------------------------------------------------------
+ * miUnionO --
+ * Handle an overlapping band for the union operation. Picks the
+ * left-most rectangle each time and merges it into the region.
+ *
+ * Results:
+ * None.
+ *
+ * Side Effects:
+ * Rectangles are overwritten in dest.rects and dest.numRects will
+ * be changed.
+ *
+ *-----------------------------------------------------------------------
+ */
+
+static void miUnionO(register QRegionPrivate &dest, register const QRect *r1, const QRect *r1End,
+ register const QRect *r2, const QRect *r2End, register int y1, register int y2)
+{
+ register QRect *pNextRect;
+
+ pNextRect = dest.rects.data() + dest.numRects;
+
+#define MERGERECT(r) \
+ if ((dest.numRects != 0) && \
+ (pNextRect[-1].top() == y1) && \
+ (pNextRect[-1].bottom() == y2) && \
+ (pNextRect[-1].right() >= r->left()-1)) { \
+ if (pNextRect[-1].right() < r->right()) { \
+ pNextRect[-1].setRight(r->right()); \
+ dest.updateInnerRect(pNextRect[-1]); \
+ Q_ASSERT(pNextRect[-1].left() <= pNextRect[-1].right()); \
+ } \
+ } else { \
+ MEMCHECK(dest, pNextRect, dest.rects) \
+ pNextRect->setCoords(r->left(), y1, r->right(), y2); \
+ dest.updateInnerRect(*pNextRect); \
+ dest.numRects++; \
+ pNextRect++; \
+ } \
+ r++;
+
+ Q_ASSERT(y1 <= y2);
+ while (r1 != r1End && r2 != r2End) {
+ if (r1->left() < r2->left()) {
+ MERGERECT(r1)
+ } else {
+ MERGERECT(r2)
+ }
+ }
+
+ if (r1 != r1End) {
+ do {
+ MERGERECT(r1)
+ } while (r1 != r1End);
+ } else {
+ while (r2 != r2End) {
+ MERGERECT(r2)
+ }
+ }
+}
+
+static void UnionRegion(const QRegionPrivate *reg1, const QRegionPrivate *reg2, QRegionPrivate &dest)
+{
+ Q_ASSERT(!isEmptyHelper(reg1) && !isEmptyHelper(reg2));
+ Q_ASSERT(!reg1->contains(*reg2));
+ Q_ASSERT(!reg2->contains(*reg1));
+ Q_ASSERT(!EqualRegion(reg1, reg2));
+ Q_ASSERT(!reg1->canAppend(reg2));
+ Q_ASSERT(!reg2->canAppend(reg1));
+
+ if (reg1->innerArea > reg2->innerArea) {
+ dest.innerArea = reg1->innerArea;
+ dest.innerRect = reg1->innerRect;
+ } else {
+ dest.innerArea = reg2->innerArea;
+ dest.innerRect = reg2->innerRect;
+ }
+ miRegionOp(dest, reg1, reg2, miUnionO, miUnionNonO, miUnionNonO);
+
+ dest.extents.setCoords(qMin(reg1->extents.left(), reg2->extents.left()),
+ qMin(reg1->extents.top(), reg2->extents.top()),
+ qMax(reg1->extents.right(), reg2->extents.right()),
+ qMax(reg1->extents.bottom(), reg2->extents.bottom()));
+}
+
+/*======================================================================
+ * Region Subtraction
+ *====================================================================*/
+
+/*-
+ *-----------------------------------------------------------------------
+ * miSubtractNonO --
+ * Deal with non-overlapping band for subtraction. Any parts from
+ * region 2 we discard. Anything from region 1 we add to the region.
+ *
+ * Results:
+ * None.
+ *
+ * Side Effects:
+ * dest may be affected.
+ *
+ *-----------------------------------------------------------------------
+ */
+
+static void miSubtractNonO1(register QRegionPrivate &dest, register const QRect *r,
+ const QRect *rEnd, register int y1, register int y2)
+{
+ register QRect *pNextRect;
+
+ pNextRect = dest.rects.data() + dest.numRects;
+
+ Q_ASSERT(y1<=y2);
+
+ while (r != rEnd) {
+ Q_ASSERT(r->left() <= r->right());
+ MEMCHECK(dest, pNextRect, dest.rects)
+ pNextRect->setCoords(r->left(), y1, r->right(), y2);
+ ++dest.numRects;
+ ++pNextRect;
+ ++r;
+ }
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * miSubtractO --
+ * Overlapping band subtraction. x1 is the left-most point not yet
+ * checked.
+ *
+ * Results:
+ * None.
+ *
+ * Side Effects:
+ * dest may have rectangles added to it.
+ *
+ *-----------------------------------------------------------------------
+ */
+
+static void miSubtractO(register QRegionPrivate &dest, register const QRect *r1, const QRect *r1End,
+ register const QRect *r2, const QRect *r2End, register int y1, register int y2)
+{
+ register QRect *pNextRect;
+ register int x1;
+
+ x1 = r1->left();
+
+ Q_ASSERT(y1 <= y2);
+ pNextRect = dest.rects.data() + dest.numRects;
+
+ while (r1 != r1End && r2 != r2End) {
+ if (r2->right() < x1) {
+ /*
+ * Subtrahend missed the boat: go to next subtrahend.
+ */
+ ++r2;
+ } else if (r2->left() <= x1) {
+ /*
+ * Subtrahend precedes minuend: nuke left edge of minuend.
+ */
+ x1 = r2->right() + 1;
+ if (x1 > r1->right()) {
+ /*
+ * Minuend completely covered: advance to next minuend and
+ * reset left fence to edge of new minuend.
+ */
+ ++r1;
+ if (r1 != r1End)
+ x1 = r1->left();
+ } else {
+ // Subtrahend now used up since it doesn't extend beyond minuend
+ ++r2;
+ }
+ } else if (r2->left() <= r1->right()) {
+ /*
+ * Left part of subtrahend covers part of minuend: add uncovered
+ * part of minuend to region and skip to next subtrahend.
+ */
+ Q_ASSERT(x1 < r2->left());
+ MEMCHECK(dest, pNextRect, dest.rects)
+ pNextRect->setCoords(x1, y1, r2->left() - 1, y2);
+ ++dest.numRects;
+ ++pNextRect;
+
+ x1 = r2->right() + 1;
+ if (x1 > r1->right()) {
+ /*
+ * Minuend used up: advance to new...
+ */
+ ++r1;
+ if (r1 != r1End)
+ x1 = r1->left();
+ } else {
+ // Subtrahend used up
+ ++r2;
+ }
+ } else {
+ /*
+ * Minuend used up: add any remaining piece before advancing.
+ */
+ if (r1->right() >= x1) {
+ MEMCHECK(dest, pNextRect, dest.rects)
+ pNextRect->setCoords(x1, y1, r1->right(), y2);
+ ++dest.numRects;
+ ++pNextRect;
+ }
+ ++r1;
+ if (r1 != r1End)
+ x1 = r1->left();
+ }
+ }
+
+ /*
+ * Add remaining minuend rectangles to region.
+ */
+ while (r1 != r1End) {
+ Q_ASSERT(x1 <= r1->right());
+ MEMCHECK(dest, pNextRect, dest.rects)
+ pNextRect->setCoords(x1, y1, r1->right(), y2);
+ ++dest.numRects;
+ ++pNextRect;
+
+ ++r1;
+ if (r1 != r1End)
+ x1 = r1->left();
+ }
+}
+
+/*-
+ *-----------------------------------------------------------------------
+ * miSubtract --
+ * Subtract regS from regM and leave the result in regD.
+ * S stands for subtrahend, M for minuend and D for difference.
+ *
+ * Side Effects:
+ * regD is overwritten.
+ *
+ *-----------------------------------------------------------------------
+ */
+
+static void SubtractRegion(QRegionPrivate *regM, QRegionPrivate *regS,
+ register QRegionPrivate &dest)
+{
+ Q_ASSERT(!isEmptyHelper(regM));
+ Q_ASSERT(!isEmptyHelper(regS));
+ Q_ASSERT(EXTENTCHECK(&regM->extents, &regS->extents));
+ Q_ASSERT(!regS->contains(*regM));
+ Q_ASSERT(!EqualRegion(regM, regS));
+
+ miRegionOp(dest, regM, regS, miSubtractO, miSubtractNonO1, 0);
+
+ /*
+ * Can't alter dest's extents before we call miRegionOp because
+ * it might be one of the source regions and miRegionOp depends
+ * on the extents of those regions being the unaltered. Besides, this
+ * way there's no checking against rectangles that will be nuked
+ * due to coalescing, so we have to examine fewer rectangles.
+ */
+ miSetExtents(dest);
+}
+
+static void XorRegion(QRegionPrivate *sra, QRegionPrivate *srb, QRegionPrivate &dest)
+{
+ Q_ASSERT(!isEmptyHelper(sra) && !isEmptyHelper(srb));
+ Q_ASSERT(EXTENTCHECK(&sra->extents, &srb->extents));
+ Q_ASSERT(!EqualRegion(sra, srb));
+
+ QRegionPrivate tra, trb;
+
+ if (!srb->contains(*sra))
+ SubtractRegion(sra, srb, tra);
+ if (!sra->contains(*srb))
+ SubtractRegion(srb, sra, trb);
+
+ Q_ASSERT(isEmptyHelper(&trb) || !tra.contains(trb));
+ Q_ASSERT(isEmptyHelper(&tra) || !trb.contains(tra));
+
+ if (isEmptyHelper(&tra)) {
+ dest = trb;
+ } else if (isEmptyHelper(&trb)) {
+ dest = tra;
+ } else if (tra.canAppend(&trb)) {
+ dest = tra;
+ dest.append(&trb);
+ } else if (trb.canAppend(&tra)) {
+ dest = trb;
+ dest.append(&tra);
+ } else {
+ UnionRegion(&tra, &trb, dest);
+ }
+}
+
+/*
+ * Check to see if two regions are equal
+ */
+static bool EqualRegion(const QRegionPrivate *r1, const QRegionPrivate *r2)
+{
+ if (r1->numRects != r2->numRects) {
+ return false;
+ } else if (r1->numRects == 0) {
+ return true;
+ } else if (r1->extents != r2->extents) {
+ return false;
+ } else if (r1->mode == QRegionPrivate::Single && r2->mode == QRegionPrivate::Single) {
+ return r1->single == r2->single;
+ } else {
+ const QRect *rr1 = (r1->mode==QRegionPrivate::Vector)?r1->rects.constData():&r1->single;
+ const QRect *rr2 = (r2->mode==QRegionPrivate::Vector)?r2->rects.constData():&r2->single;
+ for (int i = 0; i < r1->numRects; ++i, ++rr1, ++rr2) {
+ if (*rr1 != *rr2)
+ return false;
+ }
+ }
+
+ return true;
+}
+
+static bool PointInRegion(QRegionPrivate *pRegion, int x, int y)
+{
+ int i;
+
+ if (pRegion->mode == QRegionPrivate::Single)
+ return pRegion->single.contains(x, y);
+ if (isEmptyHelper(pRegion))
+ return false;
+ if (!pRegion->extents.contains(x, y))
+ return false;
+ if (pRegion->innerRect.contains(x, y))
+ return true;
+ for (i = 0; i < pRegion->numRects; ++i) {
+ if (pRegion->rects[i].contains(x, y))
+ return true;
+ }
+ return false;
+}
+
+static bool RectInRegion(register QRegionPrivate *region, int rx, int ry, uint rwidth, uint rheight)
+{
+ register const QRect *pbox;
+ register const QRect *pboxEnd;
+ QRect rect(rx, ry, rwidth, rheight);
+ register QRect *prect = &rect;
+ int partIn, partOut;
+
+ if (!region || region->numRects == 0 || !EXTENTCHECK(&region->extents, prect))
+ return RectangleOut;
+
+ partOut = false;
+ partIn = false;
+
+ /* can stop when both partOut and partIn are true, or we reach prect->y2 */
+ for (pbox = (region->mode==QRegionPrivate::Vector)?region->rects.constData():&region->single, pboxEnd = pbox + region->numRects;
+ pbox < pboxEnd; ++pbox) {
+ if (pbox->bottom() < ry)
+ continue;
+
+ if (pbox->top() > ry) {
+ partOut = true;
+ if (partIn || pbox->top() > prect->bottom())
+ break;
+ ry = pbox->top();
+ }
+
+ if (pbox->right() < rx)
+ continue; /* not far enough over yet */
+
+ if (pbox->left() > rx) {
+ partOut = true; /* missed part of rectangle to left */
+ if (partIn)
+ break;
+ }
+
+ if (pbox->left() <= prect->right()) {
+ partIn = true; /* definitely overlap */
+ if (partOut)
+ break;
+ }
+
+ if (pbox->right() >= prect->right()) {
+ ry = pbox->bottom() + 1; /* finished with this band */
+ if (ry > prect->bottom())
+ break;
+ rx = prect->left(); /* reset x out to left again */
+ } else {
+ /*
+ * Because boxes in a band are maximal width, if the first box
+ * to overlap the rectangle doesn't completely cover it in that
+ * band, the rectangle must be partially out, since some of it
+ * will be uncovered in that band. partIn will have been set true
+ * by now...
+ */
+ break;
+ }
+ }
+ return partIn ? ((ry <= prect->bottom()) ? RectanglePart : RectangleIn) : RectangleOut;
+}
+// END OF Region.c extract
+// START OF poly.h extract
+/* $XConsortium: poly.h,v 1.4 94/04/17 20:22:19 rws Exp $ */
+/************************************************************************
+
+Copyright (c) 1987 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.
+
+
+Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts.
+
+ All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the name of Digital not be
+used in advertising or publicity pertaining to distribution of the
+software without specific, written prior permission.
+
+DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
+ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
+DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
+ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+SOFTWARE.
+
+************************************************************************/
+
+/*
+ * This file contains a few macros to help track
+ * the edge of a filled object. The object is assumed
+ * to be filled in scanline order, and thus the
+ * algorithm used is an extension of Bresenham's line
+ * drawing algorithm which assumes that y is always the
+ * major axis.
+ * Since these pieces of code are the same for any filled shape,
+ * it is more convenient to gather the library in one
+ * place, but since these pieces of code are also in
+ * the inner loops of output primitives, procedure call
+ * overhead is out of the question.
+ * See the author for a derivation if needed.
+ */
+
+
+/*
+ * In scan converting polygons, we want to choose those pixels
+ * which are inside the polygon. Thus, we add .5 to the starting
+ * x coordinate for both left and right edges. Now we choose the
+ * first pixel which is inside the pgon for the left edge and the
+ * first pixel which is outside the pgon for the right edge.
+ * Draw the left pixel, but not the right.
+ *
+ * How to add .5 to the starting x coordinate:
+ * If the edge is moving to the right, then subtract dy from the
+ * error term from the general form of the algorithm.
+ * If the edge is moving to the left, then add dy to the error term.
+ *
+ * The reason for the difference between edges moving to the left
+ * and edges moving to the right is simple: If an edge is moving
+ * to the right, then we want the algorithm to flip immediately.
+ * If it is moving to the left, then we don't want it to flip until
+ * we traverse an entire pixel.
+ */
+#define BRESINITPGON(dy, x1, x2, xStart, d, m, m1, incr1, incr2) { \
+ int dx; /* local storage */ \
+\
+ /* \
+ * if the edge is horizontal, then it is ignored \
+ * and assumed not to be processed. Otherwise, do this stuff. \
+ */ \
+ if ((dy) != 0) { \
+ xStart = (x1); \
+ dx = (x2) - xStart; \
+ if (dx < 0) { \
+ m = dx / (dy); \
+ m1 = m - 1; \
+ incr1 = -2 * dx + 2 * (dy) * m1; \
+ incr2 = -2 * dx + 2 * (dy) * m; \
+ d = 2 * m * (dy) - 2 * dx - 2 * (dy); \
+ } else { \
+ m = dx / (dy); \
+ m1 = m + 1; \
+ incr1 = 2 * dx - 2 * (dy) * m1; \
+ incr2 = 2 * dx - 2 * (dy) * m; \
+ d = -2 * m * (dy) + 2 * dx; \
+ } \
+ } \
+}
+
+#define BRESINCRPGON(d, minval, m, m1, incr1, incr2) { \
+ if (m1 > 0) { \
+ if (d > 0) { \
+ minval += m1; \
+ d += incr1; \
+ } \
+ else { \
+ minval += m; \
+ d += incr2; \
+ } \
+ } else {\
+ if (d >= 0) { \
+ minval += m1; \
+ d += incr1; \
+ } \
+ else { \
+ minval += m; \
+ d += incr2; \
+ } \
+ } \
+}
+
+
+/*
+ * This structure contains all of the information needed
+ * to run the bresenham algorithm.
+ * The variables may be hardcoded into the declarations
+ * instead of using this structure to make use of
+ * register declarations.
+ */
+typedef struct {
+ int minor_axis; /* minor axis */
+ int d; /* decision variable */
+ int m, m1; /* slope and slope+1 */
+ int incr1, incr2; /* error increments */
+} BRESINFO;
+
+
+#define BRESINITPGONSTRUCT(dmaj, min1, min2, bres) \
+ BRESINITPGON(dmaj, min1, min2, bres.minor_axis, bres.d, \
+ bres.m, bres.m1, bres.incr1, bres.incr2)
+
+#define BRESINCRPGONSTRUCT(bres) \
+ BRESINCRPGON(bres.d, bres.minor_axis, bres.m, bres.m1, bres.incr1, bres.incr2)
+
+
+
+/*
+ * These are the data structures needed to scan
+ * convert regions. Two different scan conversion
+ * methods are available -- the even-odd method, and
+ * the winding number method.
+ * The even-odd rule states that a point is inside
+ * the polygon if a ray drawn from that point in any
+ * direction will pass through an odd number of
+ * path segments.
+ * By the winding number rule, a point is decided
+ * to be inside the polygon if a ray drawn from that
+ * point in any direction passes through a different
+ * number of clockwise and counter-clockwise path
+ * segments.
+ *
+ * These data structures are adapted somewhat from
+ * the algorithm in (Foley/Van Dam) for scan converting
+ * polygons.
+ * The basic algorithm is to start at the top (smallest y)
+ * of the polygon, stepping down to the bottom of
+ * the polygon by incrementing the y coordinate. We
+ * keep a list of edges which the current scanline crosses,
+ * sorted by x. This list is called the Active Edge Table (AET)
+ * As we change the y-coordinate, we update each entry in
+ * in the active edge table to reflect the edges new xcoord.
+ * This list must be sorted at each scanline in case
+ * two edges intersect.
+ * We also keep a data structure known as the Edge Table (ET),
+ * which keeps track of all the edges which the current
+ * scanline has not yet reached. The ET is basically a
+ * list of ScanLineList structures containing a list of
+ * edges which are entered at a given scanline. There is one
+ * ScanLineList per scanline at which an edge is entered.
+ * When we enter a new edge, we move it from the ET to the AET.
+ *
+ * From the AET, we can implement the even-odd rule as in
+ * (Foley/Van Dam).
+ * The winding number rule is a little trickier. We also
+ * keep the EdgeTableEntries in the AET linked by the
+ * nextWETE (winding EdgeTableEntry) link. This allows
+ * the edges to be linked just as before for updating
+ * purposes, but only uses the edges linked by the nextWETE
+ * link as edges representing spans of the polygon to
+ * drawn (as with the even-odd rule).
+ */
+
+/*
+ * for the winding number rule
+ */
+#define CLOCKWISE 1
+#define COUNTERCLOCKWISE -1
+
+typedef struct _EdgeTableEntry {
+ int ymax; /* ycoord at which we exit this edge. */
+ BRESINFO bres; /* Bresenham info to run the edge */
+ struct _EdgeTableEntry *next; /* next in the list */
+ struct _EdgeTableEntry *back; /* for insertion sort */
+ struct _EdgeTableEntry *nextWETE; /* for winding num rule */
+ int ClockWise; /* flag for winding number rule */
+} EdgeTableEntry;
+
+
+typedef struct _ScanLineList{
+ int scanline; /* the scanline represented */
+ EdgeTableEntry *edgelist; /* header node */
+ struct _ScanLineList *next; /* next in the list */
+} ScanLineList;
+
+
+typedef struct {
+ int ymax; /* ymax for the polygon */
+ int ymin; /* ymin for the polygon */
+ ScanLineList scanlines; /* header node */
+} EdgeTable;
+
+
+/*
+ * Here is a struct to help with storage allocation
+ * so we can allocate a big chunk at a time, and then take
+ * pieces from this heap when we need to.
+ */
+#define SLLSPERBLOCK 25
+
+typedef struct _ScanLineListBlock {
+ ScanLineList SLLs[SLLSPERBLOCK];
+ struct _ScanLineListBlock *next;
+} ScanLineListBlock;
+
+
+
+/*
+ *
+ * a few macros for the inner loops of the fill code where
+ * performance considerations don't allow a procedure call.
+ *
+ * Evaluate the given edge at the given scanline.
+ * If the edge has expired, then we leave it and fix up
+ * the active edge table; otherwise, we increment the
+ * x value to be ready for the next scanline.
+ * The winding number rule is in effect, so we must notify
+ * the caller when the edge has been removed so he
+ * can reorder the Winding Active Edge Table.
+ */
+#define EVALUATEEDGEWINDING(pAET, pPrevAET, y, fixWAET) { \
+ if (pAET->ymax == y) { /* leaving this edge */ \
+ pPrevAET->next = pAET->next; \
+ pAET = pPrevAET->next; \
+ fixWAET = 1; \
+ if (pAET) \
+ pAET->back = pPrevAET; \
+ } \
+ else { \
+ BRESINCRPGONSTRUCT(pAET->bres) \
+ pPrevAET = pAET; \
+ pAET = pAET->next; \
+ } \
+}
+
+
+/*
+ * Evaluate the given edge at the given scanline.
+ * If the edge has expired, then we leave it and fix up
+ * the active edge table; otherwise, we increment the
+ * x value to be ready for the next scanline.
+ * The even-odd rule is in effect.
+ */
+#define EVALUATEEDGEEVENODD(pAET, pPrevAET, y) { \
+ if (pAET->ymax == y) { /* leaving this edge */ \
+ pPrevAET->next = pAET->next; \
+ pAET = pPrevAET->next; \
+ if (pAET) \
+ pAET->back = pPrevAET; \
+ } \
+ else { \
+ BRESINCRPGONSTRUCT(pAET->bres) \
+ pPrevAET = pAET; \
+ pAET = pAET->next; \
+ } \
+}
+// END OF poly.h extract
+// START OF PolyReg.c extract
+/* $XConsortium: PolyReg.c,v 11.23 94/11/17 21:59:37 converse Exp $ */
+/************************************************************************
+
+Copyright (c) 1987 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.
+
+
+Copyright 1987 by Digital Equipment Corporation, Maynard, Massachusetts.
+
+ All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and its
+documentation for any purpose and without fee is hereby granted,
+provided that the above copyright notice appear in all copies and that
+both that copyright notice and this permission notice appear in
+supporting documentation, and that the name of Digital not be
+used in advertising or publicity pertaining to distribution of the
+software without specific, written prior permission.
+
+DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
+ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
+DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
+ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
+WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
+SOFTWARE.
+
+************************************************************************/
+/* $XFree86: xc/lib/X11/PolyReg.c,v 1.1.1.2.8.2 1998/10/04 15:22:49 hohndel Exp $ */
+
+#define LARGE_COORDINATE 1000000
+#define SMALL_COORDINATE -LARGE_COORDINATE
+
+/*
+ * InsertEdgeInET
+ *
+ * Insert the given edge into the edge table.
+ * First we must find the correct bucket in the
+ * Edge table, then find the right slot in the
+ * bucket. Finally, we can insert it.
+ *
+ */
+static void InsertEdgeInET(EdgeTable *ET, EdgeTableEntry *ETE, int scanline,
+ ScanLineListBlock **SLLBlock, int *iSLLBlock)
+{
+ register EdgeTableEntry *start, *prev;
+ register ScanLineList *pSLL, *pPrevSLL;
+ ScanLineListBlock *tmpSLLBlock;
+
+ /*
+ * find the right bucket to put the edge into
+ */
+ pPrevSLL = &ET->scanlines;
+ pSLL = pPrevSLL->next;
+ while (pSLL && (pSLL->scanline < scanline)) {
+ pPrevSLL = pSLL;
+ pSLL = pSLL->next;
+ }
+
+ /*
+ * reassign pSLL (pointer to ScanLineList) if necessary
+ */
+ if ((!pSLL) || (pSLL->scanline > scanline)) {
+ if (*iSLLBlock > SLLSPERBLOCK-1)
+ {
+ tmpSLLBlock =
+ (ScanLineListBlock *)malloc(sizeof(ScanLineListBlock));
+ (*SLLBlock)->next = tmpSLLBlock;
+ tmpSLLBlock->next = (ScanLineListBlock *)NULL;
+ *SLLBlock = tmpSLLBlock;
+ *iSLLBlock = 0;
+ }
+ pSLL = &((*SLLBlock)->SLLs[(*iSLLBlock)++]);
+
+ pSLL->next = pPrevSLL->next;
+ pSLL->edgelist = (EdgeTableEntry *)NULL;
+ pPrevSLL->next = pSLL;
+ }
+ pSLL->scanline = scanline;
+
+ /*
+ * now insert the edge in the right bucket
+ */
+ prev = 0;
+ start = pSLL->edgelist;
+ while (start && (start->bres.minor_axis < ETE->bres.minor_axis)) {
+ prev = start;
+ start = start->next;
+ }
+ ETE->next = start;
+
+ if (prev)
+ prev->next = ETE;
+ else
+ pSLL->edgelist = ETE;
+}
+
+/*
+ * CreateEdgeTable
+ *
+ * This routine creates the edge table for
+ * scan converting polygons.
+ * The Edge Table (ET) looks like:
+ *
+ * EdgeTable
+ * --------
+ * | ymax | ScanLineLists
+ * |scanline|-->------------>-------------->...
+ * -------- |scanline| |scanline|
+ * |edgelist| |edgelist|
+ * --------- ---------
+ * | |
+ * | |
+ * V V
+ * list of ETEs list of ETEs
+ *
+ * where ETE is an EdgeTableEntry data structure,
+ * and there is one ScanLineList per scanline at
+ * which an edge is initially entered.
+ *
+ */
+
+static void CreateETandAET(register int count, register const QPoint *pts,
+ EdgeTable *ET, EdgeTableEntry *AET, register EdgeTableEntry *pETEs,
+ ScanLineListBlock *pSLLBlock)
+{
+ register const QPoint *top,
+ *bottom,
+ *PrevPt,
+ *CurrPt;
+ int iSLLBlock = 0;
+ int dy;
+
+ if (count < 2)
+ return;
+
+ /*
+ * initialize the Active Edge Table
+ */
+ AET->next = 0;
+ AET->back = 0;
+ AET->nextWETE = 0;
+ AET->bres.minor_axis = SMALL_COORDINATE;
+
+ /*
+ * initialize the Edge Table.
+ */
+ ET->scanlines.next = 0;
+ ET->ymax = SMALL_COORDINATE;
+ ET->ymin = LARGE_COORDINATE;
+ pSLLBlock->next = 0;
+
+ PrevPt = &pts[count - 1];
+
+ /*
+ * for each vertex in the array of points.
+ * In this loop we are dealing with two vertices at
+ * a time -- these make up one edge of the polygon.
+ */
+ while (count--) {
+ CurrPt = pts++;
+
+ /*
+ * find out which point is above and which is below.
+ */
+ if (PrevPt->y() > CurrPt->y()) {
+ bottom = PrevPt;
+ top = CurrPt;
+ pETEs->ClockWise = 0;
+ } else {
+ bottom = CurrPt;
+ top = PrevPt;
+ pETEs->ClockWise = 1;
+ }
+
+ /*
+ * don't add horizontal edges to the Edge table.
+ */
+ if (bottom->y() != top->y()) {
+ pETEs->ymax = bottom->y() - 1; /* -1 so we don't get last scanline */
+
+ /*
+ * initialize integer edge algorithm
+ */
+ dy = bottom->y() - top->y();
+ BRESINITPGONSTRUCT(dy, top->x(), bottom->x(), pETEs->bres)
+
+ InsertEdgeInET(ET, pETEs, top->y(), &pSLLBlock, &iSLLBlock);
+
+ if (PrevPt->y() > ET->ymax)
+ ET->ymax = PrevPt->y();
+ if (PrevPt->y() < ET->ymin)
+ ET->ymin = PrevPt->y();
+ ++pETEs;
+ }
+
+ PrevPt = CurrPt;
+ }
+}
+
+/*
+ * loadAET
+ *
+ * This routine moves EdgeTableEntries from the
+ * EdgeTable into the Active Edge Table,
+ * leaving them sorted by smaller x coordinate.
+ *
+ */
+
+static void loadAET(register EdgeTableEntry *AET, register EdgeTableEntry *ETEs)
+{
+ register EdgeTableEntry *pPrevAET;
+ register EdgeTableEntry *tmp;
+
+ pPrevAET = AET;
+ AET = AET->next;
+ while (ETEs) {
+ while (AET && AET->bres.minor_axis < ETEs->bres.minor_axis) {
+ pPrevAET = AET;
+ AET = AET->next;
+ }
+ tmp = ETEs->next;
+ ETEs->next = AET;
+ if (AET)
+ AET->back = ETEs;
+ ETEs->back = pPrevAET;
+ pPrevAET->next = ETEs;
+ pPrevAET = ETEs;
+
+ ETEs = tmp;
+ }
+}
+
+/*
+ * computeWAET
+ *
+ * This routine links the AET by the
+ * nextWETE (winding EdgeTableEntry) link for
+ * use by the winding number rule. The final
+ * Active Edge Table (AET) might look something
+ * like:
+ *
+ * AET
+ * ---------- --------- ---------
+ * |ymax | |ymax | |ymax |
+ * | ... | |... | |... |
+ * |next |->|next |->|next |->...
+ * |nextWETE| |nextWETE| |nextWETE|
+ * --------- --------- ^--------
+ * | | |
+ * V-------------------> V---> ...
+ *
+ */
+static void computeWAET(register EdgeTableEntry *AET)
+{
+ register EdgeTableEntry *pWETE;
+ register int inside = 1;
+ register int isInside = 0;
+
+ AET->nextWETE = 0;
+ pWETE = AET;
+ AET = AET->next;
+ while (AET) {
+ if (AET->ClockWise)
+ ++isInside;
+ else
+ --isInside;
+
+ if (!inside && !isInside || inside && isInside) {
+ pWETE->nextWETE = AET;
+ pWETE = AET;
+ inside = !inside;
+ }
+ AET = AET->next;
+ }
+ pWETE->nextWETE = 0;
+}
+
+/*
+ * InsertionSort
+ *
+ * Just a simple insertion sort using
+ * pointers and back pointers to sort the Active
+ * Edge Table.
+ *
+ */
+
+static int InsertionSort(register EdgeTableEntry *AET)
+{
+ register EdgeTableEntry *pETEchase;
+ register EdgeTableEntry *pETEinsert;
+ register EdgeTableEntry *pETEchaseBackTMP;
+ register int changed = 0;
+
+ AET = AET->next;
+ while (AET) {
+ pETEinsert = AET;
+ pETEchase = AET;
+ while (pETEchase->back->bres.minor_axis > AET->bres.minor_axis)
+ pETEchase = pETEchase->back;
+
+ AET = AET->next;
+ if (pETEchase != pETEinsert) {
+ pETEchaseBackTMP = pETEchase->back;
+ pETEinsert->back->next = AET;
+ if (AET)
+ AET->back = pETEinsert->back;
+ pETEinsert->next = pETEchase;
+ pETEchase->back->next = pETEinsert;
+ pETEchase->back = pETEinsert;
+ pETEinsert->back = pETEchaseBackTMP;
+ changed = 1;
+ }
+ }
+ return changed;
+}
+
+/*
+ * Clean up our act.
+ */
+static void FreeStorage(register ScanLineListBlock *pSLLBlock)
+{
+ register ScanLineListBlock *tmpSLLBlock;
+
+ while (pSLLBlock) {
+ tmpSLLBlock = pSLLBlock->next;
+ free(pSLLBlock);
+ pSLLBlock = tmpSLLBlock;
+ }
+}
+
+/*
+ * Create an array of rectangles from a list of points.
+ * If indeed these things (POINTS, RECTS) are the same,
+ * then this proc is still needed, because it allocates
+ * storage for the array, which was allocated on the
+ * stack by the calling procedure.
+ *
+ */
+static void PtsToRegion(register int numFullPtBlocks, register int iCurPtBlock,
+ POINTBLOCK *FirstPtBlock, QRegionPrivate *reg)
+{
+ register QRect *rects;
+ register QPoint *pts;
+ register POINTBLOCK *CurPtBlock;
+ register int i;
+ register QRect *extents;
+ register int numRects;
+
+ extents = &reg->extents;
+ numRects = ((numFullPtBlocks * NUMPTSTOBUFFER) + iCurPtBlock) >> 1;
+
+ reg->rects.resize(numRects);
+
+ CurPtBlock = FirstPtBlock;
+ rects = reg->rects.data() - 1;
+ numRects = 0;
+ extents->setLeft(INT_MAX);
+ extents->setRight(INT_MIN);
+ reg->innerArea = -1;
+
+ for (; numFullPtBlocks >= 0; --numFullPtBlocks) {
+ /* the loop uses 2 points per iteration */
+ i = NUMPTSTOBUFFER >> 1;
+ if (!numFullPtBlocks)
+ i = iCurPtBlock >> 1;
+ if(i) {
+ for (pts = CurPtBlock->pts; i--; pts += 2) {
+ if (pts->x() == pts[1].x())
+ continue;
+ if (numRects && pts->x() == rects->left() && pts->y() == rects->bottom() + 1
+ && pts[1].x() == rects->right()+1 && (numRects == 1 || rects[-1].top() != rects->top())
+ && (i && pts[2].y() > pts[1].y())) {
+ rects->setBottom(pts[1].y());
+ reg->updateInnerRect(*rects);
+ continue;
+ }
+ ++numRects;
+ ++rects;
+ rects->setCoords(pts->x(), pts->y(), pts[1].x() - 1, pts[1].y());
+ if (rects->left() < extents->left())
+ extents->setLeft(rects->left());
+ if (rects->right() > extents->right())
+ extents->setRight(rects->right());
+ reg->updateInnerRect(*rects);
+ }
+ }
+ CurPtBlock = CurPtBlock->next;
+ }
+
+ if (numRects) {
+ extents->setTop(reg->rects[0].top());
+ extents->setBottom(rects->bottom());
+ } else {
+ extents->setCoords(0, 0, 0, 0);
+ }
+ reg->numRects = numRects;
+}
+
+/*
+ * polytoregion
+ *
+ * Scan converts a polygon by returning a run-length
+ * encoding of the resultant bitmap -- the run-length
+ * encoding is in the form of an array of rectangles.
+ */
+static QRegionPrivate *PolygonRegion(const QPoint *Pts, int Count, int rule,
+ QRegionPrivate *region)
+ //Point *Pts; /* the pts */
+ //int Count; /* number of pts */
+ //int rule; /* winding rule */
+{
+ register EdgeTableEntry *pAET; /* Active Edge Table */
+ register int y; /* current scanline */
+ register int iPts = 0; /* number of pts in buffer */
+ register EdgeTableEntry *pWETE; /* Winding Edge Table Entry*/
+ register ScanLineList *pSLL; /* current scanLineList */
+ register QPoint *pts; /* output buffer */
+ EdgeTableEntry *pPrevAET; /* ptr to previous AET */
+ EdgeTable ET; /* header node for ET */
+ EdgeTableEntry AET; /* header node for AET */
+ EdgeTableEntry *pETEs; /* EdgeTableEntries pool */
+ ScanLineListBlock SLLBlock; /* header for scanlinelist */
+ int fixWAET = false;
+ POINTBLOCK FirstPtBlock, *curPtBlock; /* PtBlock buffers */
+ POINTBLOCK *tmpPtBlock;
+ int numFullPtBlocks = 0;
+
+ region->vector();
+
+ /* special case a rectangle */
+ if (((Count == 4) ||
+ ((Count == 5) && (Pts[4].x() == Pts[0].x()) && (Pts[4].y() == Pts[0].y())))
+ && (((Pts[0].y() == Pts[1].y()) && (Pts[1].x() == Pts[2].x()) && (Pts[2].y() == Pts[3].y())
+ && (Pts[3].x() == Pts[0].x())) || ((Pts[0].x() == Pts[1].x())
+ && (Pts[1].y() == Pts[2].y()) && (Pts[2].x() == Pts[3].x())
+ && (Pts[3].y() == Pts[0].y())))) {
+ int x = qMin(Pts[0].x(), Pts[2].x());
+ region->extents.setLeft(x);
+ int y = qMin(Pts[0].y(), Pts[2].y());
+ region->extents.setTop(y);
+ region->extents.setWidth(qMax(Pts[0].x(), Pts[2].x()) - x);
+ region->extents.setHeight(qMax(Pts[0].y(), Pts[2].y()) - y);
+ if ((region->extents.left() <= region->extents.right()) &&
+ (region->extents.top() <= region->extents.bottom())) {
+ region->numRects = 1;
+ region->rects.resize(1);
+ region->rects[0] = region->extents;
+ region->innerRect = region->extents;
+ region->innerArea = region->innerRect.width() * region->innerRect.height();
+ }
+ return region;
+ }
+
+ if (!(pETEs = static_cast<EdgeTableEntry *>(malloc(sizeof(EdgeTableEntry) * Count))))
+ return 0;
+
+ pts = FirstPtBlock.pts;
+ CreateETandAET(Count, Pts, &ET, &AET, pETEs, &SLLBlock);
+ pSLL = ET.scanlines.next;
+ curPtBlock = &FirstPtBlock;
+
+ if (rule == EvenOddRule) {
+ /*
+ * for each scanline
+ */
+ for (y = ET.ymin; y < ET.ymax; ++y) {
+ /*
+ * Add a new edge to the active edge table when we
+ * get to the next edge.
+ */
+ if (pSLL && y == pSLL->scanline) {
+ loadAET(&AET, pSLL->edgelist);
+ pSLL = pSLL->next;
+ }
+ pPrevAET = &AET;
+ pAET = AET.next;
+
+ /*
+ * for each active edge
+ */
+ while (pAET) {
+ pts->setX(pAET->bres.minor_axis);
+ pts->setY(y);
+ ++pts;
+ ++iPts;
+
+ /*
+ * send out the buffer
+ */
+ if (iPts == NUMPTSTOBUFFER) {
+ tmpPtBlock = (POINTBLOCK *)malloc(sizeof(POINTBLOCK));
+ curPtBlock->next = tmpPtBlock;
+ curPtBlock = tmpPtBlock;
+ pts = curPtBlock->pts;
+ ++numFullPtBlocks;
+ iPts = 0;
+ }
+ EVALUATEEDGEEVENODD(pAET, pPrevAET, y)
+ }
+ InsertionSort(&AET);
+ }
+ } else {
+ /*
+ * for each scanline
+ */
+ for (y = ET.ymin; y < ET.ymax; ++y) {
+ /*
+ * Add a new edge to the active edge table when we
+ * get to the next edge.
+ */
+ if (pSLL && y == pSLL->scanline) {
+ loadAET(&AET, pSLL->edgelist);
+ computeWAET(&AET);
+ pSLL = pSLL->next;
+ }
+ pPrevAET = &AET;
+ pAET = AET.next;
+ pWETE = pAET;
+
+ /*
+ * for each active edge
+ */
+ while (pAET) {
+ /*
+ * add to the buffer only those edges that
+ * are in the Winding active edge table.
+ */
+ if (pWETE == pAET) {
+ pts->setX(pAET->bres.minor_axis);
+ pts->setY(y);
+ ++pts;
+ ++iPts;
+
+ /*
+ * send out the buffer
+ */
+ if (iPts == NUMPTSTOBUFFER) {
+ tmpPtBlock = static_cast<POINTBLOCK *>(malloc(sizeof(POINTBLOCK)));
+ curPtBlock->next = tmpPtBlock;
+ curPtBlock = tmpPtBlock;
+ pts = curPtBlock->pts;
+ ++numFullPtBlocks;
+ iPts = 0;
+ }
+ pWETE = pWETE->nextWETE;
+ }
+ EVALUATEEDGEWINDING(pAET, pPrevAET, y, fixWAET)
+ }
+
+ /*
+ * recompute the winding active edge table if
+ * we just resorted or have exited an edge.
+ */
+ if (InsertionSort(&AET) || fixWAET) {
+ computeWAET(&AET);
+ fixWAET = false;
+ }
+ }
+ }
+ FreeStorage(SLLBlock.next);
+ PtsToRegion(numFullPtBlocks, iPts, &FirstPtBlock, region);
+ for (curPtBlock = FirstPtBlock.next; --numFullPtBlocks >= 0;) {
+ tmpPtBlock = curPtBlock->next;
+ free(curPtBlock);
+ curPtBlock = tmpPtBlock;
+ }
+ free(pETEs);
+ return region;
+}
+// END OF PolyReg.c extract
+
+QRegionPrivate *qt_bitmapToRegion(const QBitmap& bitmap, QRegionPrivate *region)
+{
+ region->vector();
+
+ QImage image = bitmap.toImage();
+
+ QRect xr;
+
+#define AddSpan \
+ { \
+ xr.setCoords(prev1, y, x-1, y); \
+ UnionRectWithRegion(&xr, region, *region); \
+ }
+
+ const uchar zero = 0;
+ bool little = image.format() == QImage::Format_MonoLSB;
+
+ int x,
+ y;
+ for (y = 0; y < image.height(); ++y) {
+ uchar *line = image.scanLine(y);
+ int w = image.width();
+ uchar all = zero;
+ int prev1 = -1;
+ for (x = 0; x < w;) {
+ uchar byte = line[x / 8];
+ if (x > w - 8 || byte!=all) {
+ if (little) {
+ for (int b = 8; b > 0 && x < w; --b) {
+ if (!(byte & 0x01) == !all) {
+ // More of the same
+ } else {
+ // A change.
+ if (all!=zero) {
+ AddSpan
+ all = zero;
+ } else {
+ prev1 = x;
+ all = ~zero;
+ }
+ }
+ byte >>= 1;
+ ++x;
+ }
+ } else {
+ for (int b = 8; b > 0 && x < w; --b) {
+ if (!(byte & 0x80) == !all) {
+ // More of the same
+ } else {
+ // A change.
+ if (all != zero) {
+ AddSpan
+ all = zero;
+ } else {
+ prev1 = x;
+ all = ~zero;
+ }
+ }
+ byte <<= 1;
+ ++x;
+ }
+ }
+ } else {
+ x += 8;
+ }
+ }
+ if (all != zero) {
+ AddSpan
+ }
+ }
+#undef AddSpan
+
+ return region;
+}
+
+/*
+ Constructs an empty region.
+
+ \sa isEmpty()
+*/
+
+QRegion::QRegion()
+ : d(&shared_empty)
+{
+ d->ref.ref();
+}
+
+/*
+ \overload
+
+ Create a region based on the rectange \a r with region type \a t.
+
+ If the rectangle is invalid a null region will be created.
+
+ \sa QRegion::RegionType
+*/
+
+QRegion::QRegion(const QRect &r, RegionType t)
+{
+ if (r.isEmpty()) {
+ d = &shared_empty;
+ d->ref.ref();
+ } else {
+// d = new QRegionData;
+ QRegionPrivate *rp = 0;
+ if (t == Rectangle) {
+// rp = new QRegionPrivate(r);
+ rp = qt_allocRegion(r);
+ } else if (t == Ellipse) {
+ QPainterPath path;
+ path.addEllipse(r.x(), r.y(), r.width(), r.height());
+ QPolygon a = path.toSubpathPolygons().at(0).toPolygon();
+ rp = qt_allocRegion();
+// rp = new QRegionPrivate;
+ PolygonRegion(a.constData(), a.size(), EvenOddRule, rp);
+ }
+ d = rp;
+ d->ref = 1;
+#if defined(Q_WS_X11)
+ d->rgn = 0;
+ d->xrectangles = 0;
+#elif defined(Q_WS_MAC)
+ d->rgn = 0;
+#endif
+ d->qt_rgn = rp;
+ }
+}
+
+/*
+ Constructs a polygon region from the point array \a a with the fill rule
+ specified by \a fillRule.
+
+ If \a fillRule is \l{Qt::WindingFill}, the polygon region is defined
+ using the winding algorithm; if it is \l{Qt::OddEvenFill}, the odd-even fill
+ algorithm is used.
+
+ \warning This constructor can be used to create complex regions that will
+ slow down painting when used.
+*/
+
+QRegion::QRegion(const QPolygon &a, Qt::FillRule fillRule)
+{
+ if (a.count() > 2) {
+ //d = new QRegionData;
+ // QRegionPrivate *rp = new QRegionPrivate;
+ QRegionPrivate *rp = qt_allocRegion();
+ PolygonRegion(a.constData(), a.size(),
+ fillRule == Qt::WindingFill ? WindingRule : EvenOddRule, rp);
+ d = rp;
+ d->ref = 1;
+#if defined(Q_WS_X11)
+ d->rgn = 0;
+ d->xrectangles = 0;
+#elif defined(Q_WS_MAC)
+ d->rgn = 0;
+#endif
+ d->qt_rgn = rp;
+ } else {
+ d = &shared_empty;
+ d->ref.ref();
+ }
+}
+
+
+/*
+ Constructs a new region which is equal to region \a r.
+*/
+
+QRegion::QRegion(const QRegion &r)
+{
+ d = r.d;
+ d->ref.ref();
+}
+
+
+/*
+ Constructs a region from the bitmap \a bm.
+
+ The resulting region consists of the pixels in bitmap \a bm that
+ are Qt::color1, as if each pixel was a 1 by 1 rectangle.
+
+ This constructor may create complex regions that will slow down
+ painting when used. Note that drawing masked pixmaps can be done
+ much faster using QPixmap::setMask().
+*/
+QRegion::QRegion(const QBitmap &bm)
+{
+ if (bm.isNull()) {
+ d = &shared_empty;
+ d->ref.ref();
+ } else {
+ // d = new QRegionData;
+// QRegionPrivate *rp = new QRegionPrivate;
+ QRegionPrivate *rp = qt_allocRegion();
+
+ qt_bitmapToRegion(bm, rp);
+ d = rp;
+ d->ref = 1;
+#if defined(Q_WS_X11)
+ d->rgn = 0;
+ d->xrectangles = 0;
+#elif defined(Q_WS_MAC)
+ d->rgn = 0;
+#endif
+ d->qt_rgn = rp;
+ }
+}
+
+void QRegion::cleanUp(QRegion::QRegionData *x)
+{
+ // delete x->qt_rgn;
+#if defined(Q_WS_X11)
+ if (x->rgn)
+ XDestroyRegion(x->rgn);
+ if (x->xrectangles)
+ free(x->xrectangles);
+#elif defined(Q_WS_MAC)
+ if (x->rgn)
+ qt_mac_dispose_rgn(x->rgn);
+#endif
+ if(x->qt_rgn) {
+// delete x->qt_rgn;
+ qt_freeRegion(x->qt_rgn);
+ } else {
+ delete x;
+ }
+}
+
+/*
+ Destroys the region.
+*/
+
+QRegion::~QRegion()
+{
+ if (!d->ref.deref())
+ cleanUp(d);
+}
+
+
+/*
+ Assigns \a r to this region and returns a reference to the region.
+*/
+
+QRegion &QRegion::operator=(const QRegion &r)
+{
+ r.d->ref.ref();
+ if (!d->ref.deref())
+ cleanUp(d);
+ d = r.d;
+ return *this;
+}
+
+
+/*
+ \internal
+*/
+
+QRegion QRegion::copy() const
+{
+ QRegion r;
+ QRegionData *x = 0; // new QRegionData;
+ QRegionPrivate *rp = 0;
+ if (d->qt_rgn)
+// rp = new QRegionPrivate(*d->qt_rgn);
+ rp = qt_allocRegion(*d->qt_rgn);
+ else
+ rp = qt_allocRegion();
+ x = rp;
+ x->qt_rgn = rp;
+ x->ref = 1;
+#if defined(Q_WS_X11)
+ x->rgn = 0;
+ x->xrectangles = 0;
+#elif defined(Q_WS_MAC)
+ x->rgn = 0;
+#endif
+
+ if (!r.d->ref.deref())
+ cleanUp(r.d);
+ r.d = x;
+ return r;
+}
+
+/*
+ Returns true if the region is empty; otherwise returns false. An
+ empty region is a region that contains no points.
+
+ Example:
+ \snippet doc/src/snippets/code/src.gui.painting.qregion_qws.cpp 0
+*/
+
+bool QRegion::isEmpty() const
+{
+ return d == &shared_empty || d->qt_rgn->numRects == 0;
+}
+
+
+/*
+ Returns true if the region contains the point \a p; otherwise
+ returns false.
+*/
+
+bool QRegion::contains(const QPoint &p) const
+{
+ return PointInRegion(d->qt_rgn, p.x(), p.y());
+}
+
+/*
+ \overload
+
+ Returns true if the region overlaps the rectangle \a r; otherwise
+ returns false.
+*/
+
+bool QRegion::contains(const QRect &r) const
+{
+ if(!d->qt_rgn)
+ return false;
+ if(d->qt_rgn->mode == QRegionPrivate::Single)
+ return d->qt_rgn->single.contains(r);
+
+ return RectInRegion(d->qt_rgn, r.left(), r.top(), r.width(), r.height()) != RectangleOut;
+}
+
+
+
+/*
+ Translates (moves) the region \a dx along the X axis and \a dy
+ along the Y axis.
+*/
+
+void QRegion::translate(int dx, int dy)
+{
+ if ((dx == 0 && dy == 0) || isEmptyHelper(d->qt_rgn))
+ return;
+
+ detach();
+ OffsetRegion(*d->qt_rgn, dx, dy);
+#if defined(Q_WS_X11)
+ if (d->xrectangles) {
+ free(d->xrectangles);
+ d->xrectangles = 0;
+ }
+#elif defined(Q_WS_MAC)
+ if(d->rgn) {
+ qt_mac_dispose_rgn(d->rgn);
+ d->rgn = 0;
+ }
+#endif
+}
+
+/*
+ \fn QRegion QRegion::unite(const QRegion &r) const
+ \obsolete
+
+ Use united(\a r) instead.
+*/
+
+/*
+ \fn QRegion QRegion::united(const QRegion &r) const
+ \since 4.2
+
+ Returns a region which is the union of this region and \a r.
+
+ \img runion.png Region Union
+
+ The figure shows the union of two elliptical regions.
+
+ \sa intersected(), subtracted(), xored()
+*/
+
+QRegion QRegion::unite(const QRegion &r) const
+{
+ if (isEmptyHelper(d->qt_rgn))
+ return r;
+ if (isEmptyHelper(r.d->qt_rgn))
+ return *this;
+
+ if (d->qt_rgn->contains(*r.d->qt_rgn)) {
+ return *this;
+ } else if (r.d->qt_rgn->contains(*d->qt_rgn)) {
+ return r;
+ } else if (d->qt_rgn->canAppend(r.d->qt_rgn)) {
+ QRegion result(*this);
+ result.detach();
+ result.d->qt_rgn->append(r.d->qt_rgn);
+ return result;
+ } else if (r.d->qt_rgn->canAppend(d->qt_rgn)) {
+ QRegion result(r);
+ result.detach();
+ result.d->qt_rgn->append(d->qt_rgn);
+ return result;
+ } else if (EqualRegion(d->qt_rgn, r.d->qt_rgn)) {
+ return *this;
+ } else {
+ QRegion result;
+ result.detach();
+ UnionRegion(d->qt_rgn, r.d->qt_rgn, *result.d->qt_rgn);
+ return result;
+ }
+}
+
+QRegion& QRegion::operator+=(const QRegion &r)
+{
+ if (isEmptyHelper(d->qt_rgn))
+ return *this = r;
+ if (isEmptyHelper(r.d->qt_rgn))
+ return *this;
+
+ if (d->qt_rgn->contains(*r.d->qt_rgn)) {
+ return *this;
+ } else if (r.d->qt_rgn->contains(*d->qt_rgn)) {
+ return *this = r;
+ } else if (d->qt_rgn->canAppend(r.d->qt_rgn)) {
+ detach();
+ d->qt_rgn->append(r.d->qt_rgn);
+ return *this;
+ } else if (d->qt_rgn->canPrepend(r.d->qt_rgn)) {
+ detach();
+ d->qt_rgn->prepend(r.d->qt_rgn);
+ return *this;
+ } else if (EqualRegion(d->qt_rgn, r.d->qt_rgn)) {
+ return *this;
+ }
+
+ return *this = unite(r);
+}
+
+/*
+ \fn QRegion QRegion::intersect(const QRegion &r) const
+ \obsolete
+
+ Use intersected(\a r) instead.
+*/
+
+/*
+ \fn QRegion QRegion::intersected(const QRegion &r) const
+ \since 4.2
+
+ Returns a region which is the intersection of this region and \a r.
+
+ \img rintersect.png Region Intersection
+
+ The figure shows the intersection of two elliptical regions.
+*/
+
+QRegion QRegion::intersect(const QRegion &r) const
+{
+ if (isEmptyHelper(d->qt_rgn) || isEmptyHelper(r.d->qt_rgn)
+ || !EXTENTCHECK(&d->qt_rgn->extents, &r.d->qt_rgn->extents))
+ return QRegion();
+
+ /* this is fully contained in r */
+ if (r.d->qt_rgn->contains(*d->qt_rgn))
+ return *this;
+
+ /* r is fully contained in this */
+ if (d->qt_rgn->contains(*r.d->qt_rgn))
+ return r;
+
+ if(r.d->qt_rgn->mode == QRegionPrivate::Single &&
+ d->qt_rgn->mode == QRegionPrivate::Single)
+ return QRegion(r.d->qt_rgn->single.intersected(d->qt_rgn->single));
+#ifdef QT_GREENPHONE_OPT
+ else if(r.d->qt_rgn->mode == QRegionPrivate::Single)
+ return intersect(r.d->qt_rgn->single);
+ else if(d->qt_rgn->mode == QRegionPrivate::Single)
+ return r.intersect(d->qt_rgn->single);
+#endif
+
+ QRegion result;
+ result.detach();
+ miRegionOp(*result.d->qt_rgn, d->qt_rgn, r.d->qt_rgn, miIntersectO, 0, 0);
+
+ /*
+ * Can't alter dest's extents before we call miRegionOp because
+ * it might be one of the source regions and miRegionOp depends
+ * on the extents of those regions being the same. Besides, this
+ * way there's no checking against rectangles that will be nuked
+ * due to coalescing, so we have to examine fewer rectangles.
+ */
+ miSetExtents(*result.d->qt_rgn);
+ return result;
+}
+
+#ifdef QT_GREENPHONE_OPT
+/*
+ \overload
+ */
+QRegion QRegion::intersect(const QRect &r) const
+{
+ // No intersection
+ if(r.isEmpty() || isEmpty() || !EXTENTCHECK(&r, &d->qt_rgn->extents))
+ return QRegion();
+
+ // This is fully contained in r
+ if(CONTAINSCHECK(r, d->qt_rgn->extents))
+ return *this;
+
+ // r is fully contained in this
+ if(CONTAINSCHECK(d->qt_rgn->innerRect, r))
+ return QRegion(r);
+
+ if(d->qt_rgn->mode == QRegionPrivate::Single) {
+ return QRegion(d->qt_rgn->single & r);
+ } else {
+ QRegion rv(*this);
+ rv.detach();
+
+ rv.d->qt_rgn->extents &= r;
+ rv.d->qt_rgn->innerRect &= r;
+ rv.d->qt_rgn->innerArea = rv.d->qt_rgn->innerRect.height() *
+ rv.d->qt_rgn->innerRect.width();
+
+ int numRects = 0;
+ for(int ii = 0; ii < rv.d->qt_rgn->numRects; ++ii) {
+ QRect result = rv.d->qt_rgn->rects[ii] & r;
+ if(!result.isEmpty())
+ rv.d->qt_rgn->rects[numRects++] = result;
+ }
+ rv.d->qt_rgn->numRects = numRects;
+ return rv;
+ }
+}
+
+/*
+ \overload
+ */
+const QRegion QRegion::operator&(const QRect &r) const
+{
+ return intersect(r);
+}
+
+/*
+ \overload
+ */
+QRegion& QRegion::operator&=(const QRect &r)
+{
+ if(isEmpty() || CONTAINSCHECK(r, d->qt_rgn->extents)) {
+ // Do nothing
+ } else if(r.isEmpty() || !EXTENTCHECK(&r, &d->qt_rgn->extents)) {
+ *this = QRegion();
+ } else if(CONTAINSCHECK(d->qt_rgn->innerRect, r)) {
+ *this = QRegion(r);
+ } else {
+ detach();
+ if(d->qt_rgn->mode == QRegionPrivate::Single) {
+ QRect result = d->qt_rgn->single & r;
+ d->qt_rgn->single = result;
+ d->qt_rgn->extents = result;
+ d->qt_rgn->innerRect = result;
+ d->qt_rgn->innerArea = result.height() * result.width();
+ } else {
+ d->qt_rgn->extents &= r;
+ d->qt_rgn->innerRect &= r;
+ d->qt_rgn->innerArea = d->qt_rgn->innerRect.height() *
+ d->qt_rgn->innerRect.width();
+
+ int numRects = 0;
+ for(int ii = 0; ii < d->qt_rgn->numRects; ++ii) {
+ QRect result = d->qt_rgn->rects[ii] & r;
+ if(!result.isEmpty())
+ d->qt_rgn->rects[numRects++] = result;
+ }
+ d->qt_rgn->numRects = numRects;
+ }
+ }
+ return *this;
+}
+#endif
+
+/*
+ \fn QRegion QRegion::subtract(const QRegion &r) const
+ \obsolete
+
+ Use subtracted(\a r) instead.
+*/
+
+/*
+ \fn QRegion QRegion::subtracted(const QRegion &r) const
+ \since 4.2
+
+ Returns a region which is \a r subtracted from this region.
+
+ \img rsubtract.png Region Subtraction
+
+ The figure shows the result when the ellipse on the right is
+ subtracted from the ellipse on the left (\c {left - right}).
+
+ \sa intersected(), united(), xored()
+*/
+
+QRegion QRegion::subtract(const QRegion &r) const
+{
+ if (isEmptyHelper(d->qt_rgn) || isEmptyHelper(r.d->qt_rgn))
+ return *this;
+ if (r.d->qt_rgn->contains(*d->qt_rgn))
+ return QRegion();
+ if (!EXTENTCHECK(&d->qt_rgn->extents, &r.d->qt_rgn->extents))
+ return *this;
+ if (EqualRegion(d->qt_rgn, r.d->qt_rgn))
+ return QRegion();
+
+ QRegion result;
+ result.detach();
+ SubtractRegion(d->qt_rgn, r.d->qt_rgn, *result.d->qt_rgn);
+ return result;
+}
+
+/*
+ \fn QRegion QRegion::eor(const QRegion &r) const
+ \obsolete
+
+ Use xored(\a r) instead.
+*/
+
+/*
+ \fn QRegion QRegion::xored(const QRegion &r) const
+ \since 4.2
+
+ Returns a region which is the exclusive or (XOR) of this region
+ and \a r.
+
+ \img rxor.png Region XORed
+
+ The figure shows the exclusive or of two elliptical regions.
+
+ \sa intersected(), united(), subtracted()
+*/
+
+QRegion QRegion::eor(const QRegion &r) const
+{
+ if (isEmptyHelper(d->qt_rgn)) {
+ return r;
+ } else if (isEmptyHelper(r.d->qt_rgn)) {
+ return *this;
+ } else if (!EXTENTCHECK(&d->qt_rgn->extents, &r.d->qt_rgn->extents)) {
+ return (*this + r);
+ } else if (EqualRegion(d->qt_rgn, r.d->qt_rgn)) {
+ return QRegion();
+ } else {
+ QRegion result;
+ result.detach();
+ XorRegion(d->qt_rgn, r.d->qt_rgn, *result.d->qt_rgn);
+ return result;
+ }
+}
+
+/*
+ Returns the bounding rectangle of this region. An empty region
+ gives a rectangle that is QRect::isNull().
+*/
+
+QRect QRegion::boundingRect() const
+{
+ if (isEmpty())
+ return QRect();
+ return d->qt_rgn->extents;
+}
+
+/* \internal
+ Returns true if \a rect is guaranteed to be fully contained in \a region.
+ A false return value does not guarantee the opposite.
+*/
+bool qt_region_strictContains(const QRegion &region, const QRect &rect)
+{
+ if (isEmptyHelper(region.d->qt_rgn) || !rect.isValid())
+ return false;
+
+#if 0 // TEST_INNERRECT
+ static bool guard = false;
+ if (guard)
+ return QRect();
+ guard = true;
+ QRegion inner = region.d->qt_rgn->innerRect;
+ Q_ASSERT((inner - region).isEmpty());
+ guard = false;
+
+ int maxArea = 0;
+ for (int i = 0; i < region.d->qt_rgn->numRects; ++i) {
+ const QRect r = region.d->qt_rgn->rects.at(i);
+ if (r.width() * r.height() > maxArea)
+ maxArea = r.width() * r.height();
+ }
+
+ if (maxArea > region.d->qt_rgn->innerArea) {
+ qDebug() << "not largest rectangle" << region << region.d->qt_rgn->innerRect;
+ }
+ Q_ASSERT(maxArea <= region.d->qt_rgn->innerArea);
+#endif
+
+ const QRect r1 = region.d->qt_rgn->innerRect;
+ return (rect.left() >= r1.left() && rect.right() <= r1.right()
+ && rect.top() >= r1.top() && rect.bottom() <= r1.bottom());
+}
+
+/*
+ Returns an array of non-overlapping rectangles that make up the
+ region.
+
+ The union of all the rectangles is equal to the original region.
+*/
+QVector<QRect> QRegion::rects() const
+{
+ if (d->qt_rgn) {
+ d->qt_rgn->vector();
+ d->qt_rgn->rects.resize(d->qt_rgn->numRects);
+ return d->qt_rgn->rects;
+ } else {
+ return QVector<QRect>();
+ }
+}
+
+/*
+ \fn void QRegion::setRects(const QRect *rects, int number)
+
+ Sets the region using the array of rectangles specified by \a rects and
+ \a number.
+ The rectangles \e must be optimally Y-X sorted and follow these restrictions:
+
+ \list
+ \o The rectangles must not intersect.
+ \o All rectangles with a given top coordinate must have the same height.
+ \o No two rectangles may abut horizontally (they should be combined
+ into a single wider rectangle in that case).
+ \o The rectangles must be sorted in ascending order, with Y as the major
+ sort key and X as the minor sort key.
+ \endlist
+ \omit
+ Only some platforms have these restrictions (Qt for Embedded Linux, X11 and Mac OS X).
+ \endomit
+*/
+void QRegion::setRects(const QRect *rects, int num)
+{
+ *this = QRegion();
+ if (!rects || num == 0 || (num == 1 && rects->isEmpty()))
+ return;
+
+ detach();
+
+ if(num == 1) {
+ d->qt_rgn->single = *rects;
+ d->qt_rgn->mode = QRegionPrivate::Single;
+ d->qt_rgn->numRects = num;
+ d->qt_rgn->extents = *rects;
+ d->qt_rgn->innerRect = *rects;
+ } else {
+ d->qt_rgn->mode = QRegionPrivate::Vector;
+ d->qt_rgn->rects.resize(num);
+ d->qt_rgn->numRects = num;
+ int left = INT_MAX,
+ right = INT_MIN,
+ top = INT_MAX,
+ bottom = INT_MIN;
+ for (int i = 0; i < num; ++i) {
+ const QRect &rect = rects[i];
+ d->qt_rgn->rects[i] = rect;
+ left = qMin(rect.left(), left);
+ right = qMax(rect.right(), right);
+ top = qMin(rect.top(), top);
+ bottom = qMax(rect.bottom(), bottom);
+ d->qt_rgn->updateInnerRect(rect);
+ }
+ d->qt_rgn->extents = QRect(QPoint(left, top), QPoint(right, bottom));
+ }
+}
+
+/*
+ Returns true if the region is equal to \a r; otherwise returns
+ false.
+*/
+
+bool QRegion::operator==(const QRegion &r) const
+{
+ if (!d->qt_rgn || !r.d->qt_rgn)
+ return r.d->qt_rgn == d->qt_rgn;
+
+ if (d == r.d)
+ return true;
+ else
+ return EqualRegion(d->qt_rgn, r.d->qt_rgn);
+}
+
+#ifdef QT_GREENPHONE_OPT
+bool QRegion::isRect() const
+{
+ return d->qt_rgn && d->qt_rgn->mode == QRegionPrivate::Single;
+}
+#endif
+
+QT_END_NAMESPACE