/utils/vnc/reflector/region.c
C | 1788 lines | 1155 code | 158 blank | 475 comment | 346 complexity | c75fc1bd993eb3daddf85108e111dee4 MD5 | raw file
- /* $XFree86: xc/programs/Xserver/mi/miregion.c,v 1.8 2001/12/14 20:00:26 dawes Exp $ */
- /***********************************************************
- Copyright 1987, 1988, 1989, 1998 The Open Group
- Permission to use, copy, modify, distribute, and sell this software and its
- documentation for any purpose is hereby granted without fee, provided that
- the above copyright notice appear in all copies and that both that
- copyright notice and this permission notice appear in supporting
- documentation.
- The above copyright notice and this permission notice shall be included in
- all copies or substantial portions of the Software.
- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
- AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- Except as contained in this notice, the name of The Open Group shall not be
- used in advertising or otherwise to promote the sale, use or other dealings
- in this Software without prior written authorization from The Open Group.
-
- Copyright 1987, 1988, 1989 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.
- ******************************************************************/
- /* $Xorg: miregion.c,v 1.4 2001/02/09 02:05:21 xorgcvs Exp $ */
- /* The panoramix components contained the following notice */
- /****************************************************************
- * *
- * Copyright (c) Digital Equipment Corporation, 1991, 1997 *
- * *
- * All Rights Reserved. Unpublished rights reserved under *
- * the copyright laws of the United States. *
- * *
- * The software contained on this media is proprietary to *
- * and embodies the confidential technology of Digital *
- * Equipment Corporation. Possession, use, duplication or *
- * dissemination of the software and media is authorized only *
- * pursuant to a valid written license from Digital Equipment *
- * Corporation. *
- * *
- * RESTRICTED RIGHTS LEGEND Use, duplication, or disclosure *
- * by the U.S. Government is subject to restrictions as set *
- * forth in Subparagraph (c)(1)(ii) of DFARS 252.227-7013, *
- * or in FAR 52.227-19, as applicable. *
- * *
- *****************************************************************/
- #include <stdio.h>
- #include <stdlib.h>
- #include <string.h>
- /* Get definitions for CARD16 etc. */
- #include "rfblib.h"
- #include "region.h"
- #if defined (__GNUC__) && !defined (NO_INLINES)
- #define INLINE __inline
- #else
- #define INLINE
- #endif
- #undef assert
- #ifdef DEBUG
- #define assert(expr) {if (!(expr)) \
- FatalError("Assertion failed file %s, line %d: expr\n", \
- __FILE__, __LINE__); }
- #else
- #define assert(expr)
- #endif
- #define good(reg) assert(miValidRegion(reg))
- /*
- * The functions in this file implement the Region abstraction used extensively
- * throughout the X11 sample server. A Region is simply a set of disjoint
- * (non-overlapping) rectangles, plus an "extent" rectangle which is the
- * smallest single rectangle that contains all the non-overlapping rectangles.
- *
- * A Region is implemented as a "y-x-banded" array of rectangles. This array
- * imposes two degrees of order. First, all rectangles are sorted by top side
- * y coordinate first (y1), and then by left side x coordinate (x1).
- *
- * Furthermore, the rectangles are grouped into "bands". Each rectangle in a
- * band has the same top y coordinate (y1), and each has the same bottom y
- * coordinate (y2). Thus all rectangles in a band differ only in their left
- * and right side (x1 and x2). Bands are implicit in the array of rectangles:
- * there is no separate list of band start pointers.
- *
- * The y-x band representation does not minimize rectangles. In particular,
- * if a rectangle vertically crosses a band (the rectangle has scanlines in
- * the y1 to y2 area spanned by the band), then the rectangle may be broken
- * down into two or more smaller rectangles stacked one atop the other.
- *
- * ----------- -----------
- * | | | | band 0
- * | | -------- ----------- --------
- * | | | | in y-x banded | | | | band 1
- * | | | | form is | | | |
- * ----------- | | ----------- --------
- * | | | | band 2
- * -------- --------
- *
- * An added constraint on the rectangles is that they must cover as much
- * horizontal area as possible: no two rectangles within 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).
- *
- * Adam de Boor wrote most of the original region code. Joel McCormack
- * substantially modified or rewrote most of the core arithmetic routines,
- * and added miRegionValidate in order to support several speed improvements
- * to miValidateTree. Bob Scheifler changed the representation to be more
- * compact when empty or a single rectangle, and did a bunch of gratuitous
- * reformatting.
- */
- /* true iff two Boxes overlap */
- #define EXTENTCHECK(r1,r2) \
- (!( ((r1)->x2 <= (r2)->x1) || \
- ((r1)->x1 >= (r2)->x2) || \
- ((r1)->y2 <= (r2)->y1) || \
- ((r1)->y1 >= (r2)->y2) ) )
- /* true iff (x,y) is in Box */
- #define INBOX(r,x,y) \
- ( ((r)->x2 > x) && \
- ((r)->x1 <= x) && \
- ((r)->y2 > y) && \
- ((r)->y1 <= y) )
- /* true iff Box r1 contains Box r2 */
- #define SUBSUMES(r1,r2) \
- ( ((r1)->x1 <= (r2)->x1) && \
- ((r1)->x2 >= (r2)->x2) && \
- ((r1)->y1 <= (r2)->y1) && \
- ((r1)->y2 >= (r2)->y2) )
- #define min(a, b) (((a) < (b)) ? (a) : (b))
- #define max(a, b) (((a) > (b)) ? (a) : (b))
- #define xallocData(n) (RegDataPtr)malloc(REGION_SZOF(n))
- #define xfreeData(reg) if ((reg)->data && (reg)->data->size) \
- free((reg)->data)
- #define RECTALLOC_BAIL(pReg,n,bail) \
- if (!(pReg)->data || (((pReg)->data->numRects + (n)) > (pReg)->data->size)) \
- if (!miRectAlloc(pReg, n)) { goto bail; }
- #define RECTALLOC(pReg,n) \
- if (!(pReg)->data || (((pReg)->data->numRects + (n)) > (pReg)->data->size)) \
- if (!miRectAlloc(pReg, n)) { return FALSE; }
- #define ADDRECT(pNextRect,nx1,ny1,nx2,ny2) \
- { \
- pNextRect->x1 = nx1; \
- pNextRect->y1 = ny1; \
- pNextRect->x2 = nx2; \
- pNextRect->y2 = ny2; \
- pNextRect++; \
- }
- #define NEWRECT(pReg,pNextRect,nx1,ny1,nx2,ny2) \
- { \
- if (!(pReg)->data || ((pReg)->data->numRects == (pReg)->data->size))\
- { \
- if (!miRectAlloc(pReg, 1)) \
- return FALSE; \
- pNextRect = REGION_TOP(pReg); \
- } \
- ADDRECT(pNextRect,nx1,ny1,nx2,ny2); \
- pReg->data->numRects++; \
- assert(pReg->data->numRects<=pReg->data->size); \
- }
- #define DOWNSIZE(reg,numRects) \
- if (((numRects) < ((reg)->data->size >> 1)) && ((reg)->data->size > 50)) \
- { \
- RegDataPtr NewData; \
- NewData = (RegDataPtr)xrealloc((reg)->data, REGION_SZOF(numRects)); \
- if (NewData) \
- { \
- NewData->size = (numRects); \
- (reg)->data = NewData; \
- } \
- }
- BoxRec miEmptyBox = {0, 0, 0, 0};
- RegDataRec miEmptyData = {0, 0};
- RegDataRec miBrokenData = {0, 0};
- RegionRec miBrokenRegion = { { 0, 0, 0, 0 }, &miBrokenData };
- #ifdef DEBUG
- int
- miPrintRegion(rgn)
- RegionPtr rgn;
- {
- int num, size;
- register int i;
- BoxPtr rects;
- num = REGION_NUM_RECTS(rgn);
- size = REGION_SIZE(rgn);
- rects = REGION_RECTS(rgn);
- ErrorF("num: %d size: %d\n", num, size);
- ErrorF("extents: %d %d %d %d\n",
- rgn->extents.x1, rgn->extents.y1, rgn->extents.x2, rgn->extents.y2);
- for (i = 0; i < num; i++)
- ErrorF("%d %d %d %d \n",
- rects[i].x1, rects[i].y1, rects[i].x2, rects[i].y2);
- ErrorF("\n");
- return(num);
- }
- Bool
- miRegionsEqual(reg1, reg2)
- RegionPtr reg1;
- RegionPtr reg2;
- {
- int i;
- BoxPtr rects1, rects2;
- if (reg1->extents.x1 != reg2->extents.x1) return FALSE;
- if (reg1->extents.x2 != reg2->extents.x2) return FALSE;
- if (reg1->extents.y1 != reg2->extents.y1) return FALSE;
- if (reg1->extents.y2 != reg2->extents.y2) return FALSE;
- if (REGION_NUM_RECTS(reg1) != REGION_NUM_RECTS(reg2)) return FALSE;
-
- rects1 = REGION_RECTS(reg1);
- rects2 = REGION_RECTS(reg2);
- for (i = 0; i != REGION_NUM_RECTS(reg1); i++) {
- if (rects1[i].x1 != rects2[i].x1) return FALSE;
- if (rects1[i].x2 != rects2[i].x2) return FALSE;
- if (rects1[i].y1 != rects2[i].y1) return FALSE;
- if (rects1[i].y2 != rects2[i].y2) return FALSE;
- }
- return TRUE;
- }
- Bool
- miValidRegion(reg)
- RegionPtr reg;
- {
- register int i, numRects;
- if ((reg->extents.x1 > reg->extents.x2) ||
- (reg->extents.y1 > reg->extents.y2))
- return FALSE;
- numRects = REGION_NUM_RECTS(reg);
- if (!numRects)
- return ((reg->extents.x1 == reg->extents.x2) &&
- (reg->extents.y1 == reg->extents.y2) &&
- (reg->data->size || (reg->data == &miEmptyData)));
- else if (numRects == 1)
- return (!reg->data);
- else
- {
- register BoxPtr pboxP, pboxN;
- BoxRec box;
- pboxP = REGION_RECTS(reg);
- box = *pboxP;
- box.y2 = pboxP[numRects-1].y2;
- pboxN = pboxP + 1;
- for (i = numRects; --i > 0; pboxP++, pboxN++)
- {
- if ((pboxN->x1 >= pboxN->x2) ||
- (pboxN->y1 >= pboxN->y2))
- return FALSE;
- if (pboxN->x1 < box.x1)
- box.x1 = pboxN->x1;
- if (pboxN->x2 > box.x2)
- box.x2 = pboxN->x2;
- if ((pboxN->y1 < pboxP->y1) ||
- ((pboxN->y1 == pboxP->y1) &&
- ((pboxN->x1 < pboxP->x2) || (pboxN->y2 != pboxP->y2))))
- return FALSE;
- }
- return ((box.x1 == reg->extents.x1) &&
- (box.x2 == reg->extents.x2) &&
- (box.y1 == reg->extents.y1) &&
- (box.y2 == reg->extents.y2));
- }
- }
- #endif /* DEBUG */
- /*****************************************************************
- * RegionCreate(rect, size)
- * This routine does a simple malloc to make a structure of
- * REGION of "size" number of rectangles.
- *****************************************************************/
- RegionPtr
- miRegionCreate(rect, size)
- BoxPtr rect;
- int size;
- {
- register RegionPtr pReg;
-
- pReg = (RegionPtr)xalloc(sizeof(RegionRec));
- if (!pReg)
- return &miBrokenRegion;
- if (rect)
- {
- pReg->extents = *rect;
- pReg->data = (RegDataPtr)NULL;
- }
- else
- {
- pReg->extents = miEmptyBox;
- if ((size > 1) && (pReg->data = xallocData(size)))
- {
- pReg->data->size = size;
- pReg->data->numRects = 0;
- }
- else
- pReg->data = &miEmptyData;
- }
- return(pReg);
- }
- /*****************************************************************
- * RegionInit(pReg, rect, size)
- * Outer region rect is statically allocated.
- *****************************************************************/
- void
- miRegionInit(pReg, rect, size)
- RegionPtr pReg;
- BoxPtr rect;
- int size;
- {
- if (rect)
- {
- pReg->extents = *rect;
- pReg->data = (RegDataPtr)NULL;
- }
- else
- {
- pReg->extents = miEmptyBox;
- if ((size > 1) && (pReg->data = xallocData(size)))
- {
- pReg->data->size = size;
- pReg->data->numRects = 0;
- }
- else
- pReg->data = &miEmptyData;
- }
- }
- void
- miRegionDestroy(pReg)
- RegionPtr pReg;
- {
- good(pReg);
- xfreeData(pReg);
- if (pReg != &miBrokenRegion)
- xfree(pReg);
- }
- void
- miRegionUninit(pReg)
- RegionPtr pReg;
- {
- good(pReg);
- xfreeData(pReg);
- }
- Bool
- miRegionBreak (pReg)
- RegionPtr pReg;
- {
- xfreeData (pReg);
- pReg->extents = miEmptyBox;
- pReg->data = &miBrokenData;
- return FALSE;
- }
- Bool
- miRectAlloc(
- register RegionPtr pRgn,
- int n)
- {
- RegDataPtr data;
-
- if (!pRgn->data)
- {
- n++;
- pRgn->data = xallocData(n);
- if (!pRgn->data)
- return miRegionBreak (pRgn);
- pRgn->data->numRects = 1;
- *REGION_BOXPTR(pRgn) = pRgn->extents;
- }
- else if (!pRgn->data->size)
- {
- pRgn->data = xallocData(n);
- if (!pRgn->data)
- return miRegionBreak (pRgn);
- pRgn->data->numRects = 0;
- }
- else
- {
- if (n == 1)
- {
- n = pRgn->data->numRects;
- if (n > 500) /* XXX pick numbers out of a hat */
- n = 250;
- }
- n += pRgn->data->numRects;
- data = (RegDataPtr)xrealloc(pRgn->data, REGION_SZOF(n));
- if (!data)
- return miRegionBreak (pRgn);
- pRgn->data = data;
- }
- pRgn->data->size = n;
- return TRUE;
- }
- Bool
- miRegionCopy(dst, src)
- register RegionPtr dst;
- register RegionPtr src;
- {
- good(dst);
- good(src);
- if (dst == src)
- return TRUE;
- dst->extents = src->extents;
- if (!src->data || !src->data->size)
- {
- xfreeData(dst);
- dst->data = src->data;
- return TRUE;
- }
- if (!dst->data || (dst->data->size < src->data->numRects))
- {
- xfreeData(dst);
- dst->data = xallocData(src->data->numRects);
- if (!dst->data)
- return miRegionBreak (dst);
- dst->data->size = src->data->numRects;
- }
- dst->data->numRects = src->data->numRects;
- memmove((char *)REGION_BOXPTR(dst),(char *)REGION_BOXPTR(src),
- dst->data->numRects * sizeof(BoxRec));
- return TRUE;
- }
- /*======================================================================
- * Generic Region Operator
- *====================================================================*/
- /*-
- *-----------------------------------------------------------------------
- * miCoalesce --
- * Attempt to merge the boxes in the current band with those in the
- * previous one. We are guaranteed that the current band extends to
- * the end of the rects array. 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.
- * - pReg->data->numRects will be decreased.
- *
- *-----------------------------------------------------------------------
- */
- INLINE static int
- miCoalesce (
- register RegionPtr pReg, /* Region to coalesce */
- int prevStart, /* Index of start of previous band */
- int curStart) /* Index of start of current band */
- {
- register BoxPtr pPrevBox; /* Current box in previous band */
- register BoxPtr pCurBox; /* Current box in current band */
- register int numRects; /* Number rectangles in both bands */
- register int y2; /* Bottom of current band */
- /*
- * Figure out how many rectangles are in the band.
- */
- numRects = curStart - prevStart;
- assert(numRects == pReg->data->numRects - curStart);
- if (!numRects) return curStart;
- /*
- * The bands may only be coalesced if the bottom of the previous
- * matches the top scanline of the current.
- */
- pPrevBox = REGION_BOX(pReg, prevStart);
- pCurBox = REGION_BOX(pReg, curStart);
- if (pPrevBox->y2 != pCurBox->y1) return curStart;
- /*
- * 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.
- */
- y2 = pCurBox->y2;
- do {
- if ((pPrevBox->x1 != pCurBox->x1) || (pPrevBox->x2 != pCurBox->x2)) {
- return (curStart);
- }
- pPrevBox++;
- pCurBox++;
- numRects--;
- } while (numRects);
- /*
- * The bands may be merged, so set the bottom y of each box
- * in the previous band to the bottom y of the current band.
- */
- numRects = curStart - prevStart;
- pReg->data->numRects -= numRects;
- do {
- pPrevBox--;
- pPrevBox->y2 = y2;
- numRects--;
- } while (numRects);
- return prevStart;
- }
- /* Quicky macro to avoid trivial reject procedure calls to miCoalesce */
- #define Coalesce(newReg, prevBand, curBand) \
- if (curBand - prevBand == newReg->data->numRects - curBand) { \
- prevBand = miCoalesce(newReg, prevBand, curBand); \
- } else { \
- prevBand = curBand; \
- }
- /*-
- *-----------------------------------------------------------------------
- * miAppendNonO --
- * Handle a non-overlapping band for the union and subtract operations.
- * Just adds the (top/bottom-clipped) rectangles into the region.
- * Doesn't have to check for subsumption or anything.
- *
- * Results:
- * None.
- *
- * Side Effects:
- * pReg->data->numRects is incremented and the rectangles overwritten
- * with the rectangles we're passed.
- *
- *-----------------------------------------------------------------------
- */
- INLINE static Bool
- miAppendNonO (
- register RegionPtr pReg,
- register BoxPtr r,
- BoxPtr rEnd,
- register int y1,
- register int y2)
- {
- register BoxPtr pNextRect;
- register int newRects;
- newRects = rEnd - r;
- assert(y1 < y2);
- assert(newRects != 0);
- /* Make sure we have enough space for all rectangles to be added */
- RECTALLOC(pReg, newRects);
- pNextRect = REGION_TOP(pReg);
- pReg->data->numRects += newRects;
- do {
- assert(r->x1 < r->x2);
- ADDRECT(pNextRect, r->x1, y1, r->x2, y2);
- r++;
- } while (r != rEnd);
- return TRUE;
- }
- #define FindBand(r, rBandEnd, rEnd, ry1) \
- { \
- ry1 = r->y1; \
- rBandEnd = r+1; \
- while ((rBandEnd != rEnd) && (rBandEnd->y1 == ry1)) { \
- rBandEnd++; \
- } \
- }
- #define AppendRegions(newReg, r, rEnd) \
- { \
- int newRects; \
- if ((newRects = rEnd - r)) { \
- RECTALLOC(newReg, newRects); \
- memmove((char *)REGION_TOP(newReg),(char *)r, \
- newRects * sizeof(BoxRec)); \
- newReg->data->numRects += newRects; \
- } \
- }
- /*-
- *-----------------------------------------------------------------------
- * miRegionOp --
- * Apply an operation to two regions. Called by miUnion, miInverse,
- * miSubtract, miIntersect.... Both regions MUST have at least one
- * rectangle, and cannot be the same object.
- *
- * Results:
- * TRUE if successful.
- *
- * Side Effects:
- * The new region is overwritten.
- * pOverlap set to TRUE if overlapFunc ever returns TRUE.
- *
- * 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.
- *
- *-----------------------------------------------------------------------
- */
- typedef Bool (*OverlapProcPtr)(
- RegionPtr pReg,
- BoxPtr r1,
- BoxPtr r1End,
- BoxPtr r2,
- BoxPtr r2End,
- short y1,
- short y2,
- Bool *pOverlap);
- static Bool
- miRegionOp(
- RegionPtr newReg, /* Place to store result */
- RegionPtr reg1, /* First region in operation */
- RegionPtr reg2, /* 2d region in operation */
- OverlapProcPtr overlapFunc, /* Function to call for over-
- * lapping bands */
- Bool appendNon1, /* Append non-overlapping bands */
- /* in region 1 ? */
- Bool appendNon2, /* Append non-overlapping bands */
- /* in region 2 ? */
- Bool *pOverlap)
- {
- register BoxPtr r1; /* Pointer into first region */
- register BoxPtr r2; /* Pointer into 2d region */
- BoxPtr r1End; /* End of 1st region */
- BoxPtr r2End; /* End of 2d region */
- short ybot; /* Bottom of intersection */
- short ytop; /* Top of intersection */
- RegDataPtr oldData; /* Old data for newReg */
- int prevBand; /* Index of start of
- * previous band in newReg */
- int curBand; /* Index of start of current
- * band in newReg */
- register BoxPtr r1BandEnd; /* End of current band in r1 */
- register BoxPtr r2BandEnd; /* End of current band in r2 */
- short top; /* Top of non-overlapping band */
- short bot; /* Bottom of non-overlapping band*/
- register int r1y1; /* Temps for r1->y1 and r2->y1 */
- register int r2y1;
- int newSize;
- int numRects;
- /*
- * Break any region computed from a broken region
- */
- if (REGION_NAR (reg1) || REGION_NAR(reg2))
- return miRegionBreak (newReg);
-
- /*
- * Initialization:
- * set r1, r2, r1End and r2End appropriately, save the rectangles
- * 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 = REGION_RECTS(reg1);
- newSize = REGION_NUM_RECTS(reg1);
- r1End = r1 + newSize;
- numRects = REGION_NUM_RECTS(reg2);
- r2 = REGION_RECTS(reg2);
- r2End = r2 + numRects;
- assert(r1 != r1End);
- assert(r2 != r2End);
- oldData = (RegDataPtr)NULL;
- if (((newReg == reg1) && (newSize > 1)) ||
- ((newReg == reg2) && (numRects > 1)))
- {
- oldData = newReg->data;
- newReg->data = &miEmptyData;
- }
- /* guess at new size */
- if (numRects > newSize)
- newSize = numRects;
- newSize <<= 1;
- if (!newReg->data)
- newReg->data = &miEmptyData;
- else if (newReg->data->size)
- newReg->data->numRects = 0;
- if (newSize > newReg->data->size)
- if (!miRectAlloc(newReg, newSize))
- return FALSE;
- /*
- * Initialize ybot.
- * 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.
- */
- ybot = min(r1->y1, r2->y1);
-
- /*
- * 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 {
- /*
- * 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.
- */
- assert(r1 != r1End);
- assert(r2 != r2End);
-
- FindBand(r1, r1BandEnd, r1End, r1y1);
- FindBand(r2, r2BandEnd, r2End, r2y1);
- /*
- * 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 (r1y1 < r2y1) {
- if (appendNon1) {
- top = max(r1y1, ybot);
- bot = min(r1->y2, r2y1);
- if (top != bot) {
- curBand = newReg->data->numRects;
- miAppendNonO(newReg, r1, r1BandEnd, top, bot);
- Coalesce(newReg, prevBand, curBand);
- }
- }
- ytop = r2y1;
- } else if (r2y1 < r1y1) {
- if (appendNon2) {
- top = max(r2y1, ybot);
- bot = min(r2->y2, r1y1);
- if (top != bot) {
- curBand = newReg->data->numRects;
- miAppendNonO(newReg, r2, r2BandEnd, top, bot);
- Coalesce(newReg, prevBand, curBand);
- }
- }
- ytop = r1y1;
- } else {
- ytop = r1y1;
- }
- /*
- * Now see if we've hit an intersecting band. The two bands only
- * intersect if ybot > ytop
- */
- ybot = min(r1->y2, r2->y2);
- if (ybot > ytop) {
- curBand = newReg->data->numRects;
- (* overlapFunc)(newReg, r1, r1BandEnd, r2, r2BandEnd, ytop, ybot,
- pOverlap);
- Coalesce(newReg, prevBand, curBand);
- }
- /*
- * If we've finished with a band (y2 == ybot) we skip forward
- * in the region to the next band.
- */
- if (r1->y2 == ybot) r1 = r1BandEnd;
- if (r2->y2 == ybot) r2 = r2BandEnd;
- } while (r1 != r1End && r2 != r2End);
- /*
- * Deal with whichever region (if any) still has rectangles left.
- *
- * We only need to worry about banding and coalescing for the very first
- * band left. After that, we can just group all remaining boxes,
- * regardless of how many bands, into one final append to the list.
- */
- if ((r1 != r1End) && appendNon1) {
- /* Do first nonOverlap1Func call, which may be able to coalesce */
- FindBand(r1, r1BandEnd, r1End, r1y1);
- curBand = newReg->data->numRects;
- miAppendNonO(newReg, r1, r1BandEnd, max(r1y1, ybot), r1->y2);
- Coalesce(newReg, prevBand, curBand);
- /* Just append the rest of the boxes */
- AppendRegions(newReg, r1BandEnd, r1End);
- } else if ((r2 != r2End) && appendNon2) {
- /* Do first nonOverlap2Func call, which may be able to coalesce */
- FindBand(r2, r2BandEnd, r2End, r2y1);
- curBand = newReg->data->numRects;
- miAppendNonO(newReg, r2, r2BandEnd, max(r2y1, ybot), r2->y2);
- Coalesce(newReg, prevBand, curBand);
- /* Append rest of boxes */
- AppendRegions(newReg, r2BandEnd, r2End);
- }
- if (oldData)
- xfree(oldData);
- if (!(numRects = newReg->data->numRects))
- {
- xfreeData(newReg);
- newReg->data = &miEmptyData;
- }
- else if (numRects == 1)
- {
- newReg->extents = *REGION_BOXPTR(newReg);
- xfreeData(newReg);
- newReg->data = (RegDataPtr)NULL;
- }
- else
- {
- DOWNSIZE(newReg, numRects);
- }
- return TRUE;
- }
- /*-
- *-----------------------------------------------------------------------
- * miSetExtents --
- * Reset the extents of a region to what they should be. Called by
- * miSubtract and miIntersect as they can't figure it out along the
- * way or do so easily, as miUnion can.
- *
- * Results:
- * None.
- *
- * Side Effects:
- * The region's 'extents' structure is overwritten.
- *
- *-----------------------------------------------------------------------
- */
- void
- miSetExtents (pReg)
- register RegionPtr pReg;
- {
- register BoxPtr pBox, pBoxEnd;
- if (!pReg->data)
- return;
- if (!pReg->data->size)
- {
- pReg->extents.x2 = pReg->extents.x1;
- pReg->extents.y2 = pReg->extents.y1;
- return;
- }
- pBox = REGION_BOXPTR(pReg);
- pBoxEnd = REGION_END(pReg);
- /*
- * 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...
- */
- pReg->extents.x1 = pBox->x1;
- pReg->extents.y1 = pBox->y1;
- pReg->extents.x2 = pBoxEnd->x2;
- pReg->extents.y2 = pBoxEnd->y2;
- assert(pReg->extents.y1 < pReg->extents.y2);
- while (pBox <= pBoxEnd) {
- if (pBox->x1 < pReg->extents.x1)
- pReg->extents.x1 = pBox->x1;
- if (pBox->x2 > pReg->extents.x2)
- pReg->extents.x2 = pBox->x2;
- pBox++;
- };
- assert(pReg->extents.x1 < pReg->extents.x2);
- }
- /*======================================================================
- * Region Intersection
- *====================================================================*/
- /*-
- *-----------------------------------------------------------------------
- * miIntersectO --
- * Handle an overlapping band for miIntersect.
- *
- * Results:
- * TRUE if successful.
- *
- * Side Effects:
- * Rectangles may be added to the region.
- *
- *-----------------------------------------------------------------------
- */
- /*ARGSUSED*/
- static Bool
- miIntersectO (
- register RegionPtr pReg,
- register BoxPtr r1,
- BoxPtr r1End,
- register BoxPtr r2,
- BoxPtr r2End,
- short y1,
- short y2,
- Bool *pOverlap)
- {
- register int x1;
- register int x2;
- register BoxPtr pNextRect;
- pNextRect = REGION_TOP(pReg);
- assert(y1 < y2);
- assert(r1 != r1End && r2 != r2End);
- do {
- x1 = max(r1->x1, r2->x1);
- x2 = min(r1->x2, r2->x2);
- /*
- * If there's any overlap between the two rectangles, add that
- * overlap to the new region.
- */
- if (x1 < x2)
- NEWRECT(pReg, pNextRect, x1, y1, x2, y2);
- /*
- * Advance the pointer(s) with the leftmost right side, since the next
- * rectangle on that list may still overlap the other region's
- * current rectangle.
- */
- if (r1->x2 == x2) {
- r1++;
- }
- if (r2->x2 == x2) {
- r2++;
- }
- } while ((r1 != r1End) && (r2 != r2End));
- return TRUE;
- }
- Bool
- miIntersect(newReg, reg1, reg2)
- register RegionPtr newReg; /* destination Region */
- register RegionPtr reg1;
- register RegionPtr reg2; /* source regions */
- {
- good(reg1);
- good(reg2);
- good(newReg);
- /* check for trivial reject */
- if (REGION_NIL(reg1) || REGION_NIL(reg2) ||
- !EXTENTCHECK(®1->extents, ®2->extents))
- {
- /* Covers about 20% of all cases */
- xfreeData(newReg);
- newReg->extents.x2 = newReg->extents.x1;
- newReg->extents.y2 = newReg->extents.y1;
- if (REGION_NAR(reg1) || REGION_NAR(reg2))
- {
- newReg->data = &miBrokenData;
- return FALSE;
- }
- else
- newReg->data = &miEmptyData;
- }
- else if (!reg1->data && !reg2->data)
- {
- /* Covers about 80% of cases that aren't trivially rejected */
- newReg->extents.x1 = max(reg1->extents.x1, reg2->extents.x1);
- newReg->extents.y1 = max(reg1->extents.y1, reg2->extents.y1);
- newReg->extents.x2 = min(reg1->extents.x2, reg2->extents.x2);
- newReg->extents.y2 = min(reg1->extents.y2, reg2->extents.y2);
- xfreeData(newReg);
- newReg->data = (RegDataPtr)NULL;
- }
- else if (!reg2->data && SUBSUMES(®2->extents, ®1->extents))
- {
- return miRegionCopy(newReg, reg1);
- }
- else if (!reg1->data && SUBSUMES(®1->extents, ®2->extents))
- {
- return miRegionCopy(newReg, reg2);
- }
- else if (reg1 == reg2)
- {
- return miRegionCopy(newReg, reg1);
- }
- else
- {
- /* General purpose intersection */
- Bool overlap; /* result ignored */
- if (!miRegionOp(newReg, reg1, reg2, miIntersectO, FALSE, FALSE,
- &overlap))
- return FALSE;
- miSetExtents(newReg);
- }
- good(newReg);
- return(TRUE);
- }
- #define MERGERECT(r) \
- { \
- if (r->x1 <= x2) { \
- /* Merge with current rectangle */ \
- if (r->x1 < x2) *pOverlap = TRUE; \
- if (x2 < r->x2) x2 = r->x2; \
- } else { \
- /* Add current rectangle, start new one */ \
- NEWRECT(pReg, pNextRect, x1, y1, x2, y2); \
- x1 = r->x1; \
- x2 = r->x2; \
- } \
- r++; \
- }
- /*======================================================================
- * Region Union
- *====================================================================*/
- /*-
- *-----------------------------------------------------------------------
- * miUnionO --
- * Handle an overlapping band for the union operation. Picks the
- * left-most rectangle each time and merges it into the region.
- *
- * Results:
- * TRUE if successful.
- *
- * Side Effects:
- * pReg is overwritten.
- * pOverlap is set to TRUE if any boxes overlap.
- *
- *-----------------------------------------------------------------------
- */
- static Bool
- miUnionO (
- register RegionPtr pReg,
- register BoxPtr r1,
- BoxPtr r1End,
- register BoxPtr r2,
- BoxPtr r2End,
- short y1,
- short y2,
- Bool *pOverlap)
- {
- register BoxPtr pNextRect;
- register int x1; /* left and right side of current union */
- register int x2;
- assert (y1 < y2);
- assert(r1 != r1End && r2 != r2End);
- pNextRect = REGION_TOP(pReg);
- /* Start off current rectangle */
- if (r1->x1 < r2->x1)
- {
- x1 = r1->x1;
- x2 = r1->x2;
- r1++;
- }
- else
- {
- x1 = r2->x1;
- x2 = r2->x2;
- r2++;
- }
- while (r1 != r1End && r2 != r2End)
- {
- if (r1->x1 < r2->x1) MERGERECT(r1) else MERGERECT(r2);
- }
- /* Finish off whoever (if any) is left */
- if (r1 != r1End)
- {
- do
- {
- MERGERECT(r1);
- } while (r1 != r1End);
- }
- else if (r2 != r2End)
- {
- do
- {
- MERGERECT(r2);
- } while (r2 != r2End);
- }
-
- /* Add current rectangle */
- NEWRECT(pReg, pNextRect, x1, y1, x2, y2);
- return TRUE;
- }
- Bool
- miUnion(newReg, reg1, reg2)
- RegionPtr newReg; /* destination Region */
- register RegionPtr reg1;
- register RegionPtr reg2; /* source regions */
- {
- Bool overlap; /* result ignored */
- /* Return TRUE if some overlap between reg1, reg2 */
- good(reg1);
- good(reg2);
- good(newReg);
- /* checks all the simple cases */
- /*
- * Region 1 and 2 are the same
- */
- if (reg1 == reg2)
- {
- return miRegionCopy(newReg, reg1);
- }
- /*
- * Region 1 is empty
- */
- if (REGION_NIL(reg1))
- {
- if (REGION_NAR(reg1))
- return miRegionBreak (newReg);
- if (newReg != reg2)
- return miRegionCopy(newReg, reg2);
- return TRUE;
- }
- /*
- * Region 2 is empty
- */
- if (REGION_NIL(reg2))
- {
- if (REGION_NAR(reg2))
- return miRegionBreak (newReg);
- if (newReg != reg1)
- return miRegionCopy(newReg, reg1);
- return TRUE;
- }
- /*
- * Region 1 completely subsumes region 2
- */
- if (!reg1->data && SUBSUMES(®1->extents, ®2->extents))
- {
- if (newReg != reg1)
- return miRegionCopy(newReg, reg1);
- return TRUE;
- }
- /*
- * Region 2 completely subsumes region 1
- */
- if (!reg2->data && SUBSUMES(®2->extents, ®1->extents))
- {
- if (newReg != reg2)
- return miRegionCopy(newReg, reg2);
- return TRUE;
- }
- if (!miRegionOp(newReg, reg1, reg2, miUnionO, TRUE, TRUE, &overlap))
- return FALSE;
- newReg->extents.x1 = min(reg1->extents.x1, reg2->extents.x1);
- newReg->extents.y1 = min(reg1->extents.y1, reg2->extents.y1);
- newReg->extents.x2 = max(reg1->extents.x2, reg2->extents.x2);
- newReg->extents.y2 = max(reg1->extents.y2, reg2->extents.y2);
- good(newReg);
- return TRUE;
- }
- /*======================================================================
- * Batch Rectangle Union
- *====================================================================*/
- /*-
- *-----------------------------------------------------------------------
- * miRegionAppend --
- *
- * "Append" the rgn rectangles onto the end of dstrgn, maintaining
- * knowledge of YX-banding when it's easy. Otherwise, dstrgn just
- * becomes a non-y-x-banded random collection of rectangles, and not
- * yet a true region. After a sequence of appends, the caller must
- * call miRegionValidate to ensure that a valid region is constructed.
- *
- * Results:
- * TRUE if successful.
- *
- * Side Effects:
- * dstrgn is modified if rgn has rectangles.
- *
- */
- Bool
- miRegionAppend(dstrgn, rgn)
- register RegionPtr dstrgn;
- register RegionPtr rgn;
- {
- int numRects, dnumRects, size;
- BoxPtr new, old;
- Bool prepend;
- if (REGION_NAR(rgn))
- return miRegionBreak (dstrgn);
-
- if (!rgn->data && (dstrgn->data == &miEmptyData))
- {
- dstrgn->extents = rgn->extents;
- dstrgn->data = (RegDataPtr)NULL;
- return TRUE;
- }
- numRects = REGION_NUM_RECTS(rgn);
- if (!numRects)
- return TRUE;
- prepend = FALSE;
- size = numRects;
- dnumRects = REGION_NUM_RECTS(dstrgn);
- if (!dnumRects && (size < 200))
- size = 200; /* XXX pick numbers out of a hat */
- RECTALLOC(dstrgn, size);
- old = REGION_RECTS(rgn);
- if (!dnumRects)
- dstrgn->extents = rgn->extents;
- else if (dstrgn->extents.x2 > dstrgn->extents.x1)
- {
- register BoxPtr first, last;
- first = old;
- last = REGION_BOXPTR(dstrgn) + (dnumRects - 1);
- if ((first->y1 > last->y2) ||
- ((first->y1 == last->y1) && (first->y2 == last->y2) &&
- (first->x1 > last->x2)))
- {
- if (rgn->extents.x1 < dstrgn->extents.x1)
- dstrgn->extents.x1 = rgn->extents.x1;
- if (rgn->extents.x2 > dstrgn->extents.x2)
- dstrgn->extents.x2 = rgn->extents.x2;
- dstrgn->extents.y2 = rgn->extents.y2;
- }
- else
- {
- first = REGION_BOXPTR(dstrgn);
- last = old + (numRects - 1);
- if ((first->y1 > last->y2) ||
- ((first->y1 == last->y1) && (first->y2 == last->y2) &&
- (first->x1 > last->x2)))
- {
- prepend = TRUE;
- if (rgn->extents.x1 < dstrgn->extents.x1)
- dstrgn->extents.x1 = rgn->extents.x1;
- if (rgn->extents.x2 > dstrgn->extents.x2)
- dstrgn->extents.x2 = rgn->extents.x2;
- dstrgn->extents.y1 = rgn->extents.y1;
- }
- else
- dstrgn->extents.x2 = dstrgn->extents.x1;
- }
- }
- if (prepend)
- {
- new = REGION_BOX(dstrgn, numRects);
- if (dnumRects == 1)
- *new = *REGION_BOXPTR(dstrgn);
- else
- memmove((char *)new,(char *)REGION_BOXPTR(dstrgn),
- dnumRects * sizeof(BoxRec));
- new = REGION_BOXPTR(dstrgn);
- }
- else
- new = REGION_BOXPTR(dstrgn) + dnumRects;
- if (numRects == 1)
- *new = *old;
- else
- memmove((char *)new, (char *)old, numRects * sizeof(BoxRec));
- dstrgn->data->numRects += numRects;
- return TRUE;
- }
-
- #define ExchangeRects(a, b) \
- { \
- BoxRec t; \
- t = rects[a]; \
- rects[a] = rects[b]; \
- rects[b] = t; \
- }
- static void
- QuickSortRects(
- register BoxRec rects[],
- register int numRects)
- {
- register int y1;
- register int x1;
- register int i, j;
- register BoxPtr r;
- /* Always called with numRects > 1 */
- do
- {
- if (numRects == 2)
- {
- if (rects[0].y1 > rects[1].y1 ||
- (rects[0].y1 == rects[1].y1 && rects[0].x1 > rects[1].x1))
- ExchangeRects(0, 1);
- return;
- }
- /* Choose partition element, stick in location 0 */
- ExchangeRects(0, numRects >> 1);
- y1 = rects[0].y1;
- x1 = rects[0].x1;
- /* Partition array */
- i = 0;
- j = numRects;
- do
- {
- r = &(rects[i]);
- do
- {
- r++;
- i++;
- } while (i != numRects &&
- (r->y1 < y1 || (r->y1 == y1 && r->x1 < x1)));
- r = &(rects[j]);
- do
- {
- r--;
- j--;
- } while (y1 < r->y1 || (y1 == r->y1 && x1 < r->x1));
- if (i < j)
- ExchangeRects(i, j);
- } while (i < j);
- /* Move partition element back to middle */
- ExchangeRects(0, j);
- /* Recurse */
- if (numRects-j-1 > 1)
- QuickSortRects(&rects[j+1], numRects-j-1);
- numRects = j;
- } while (numRects > 1);
- }
- /*-
- *-----------------------------------------------------------------------
- * miRegionValidate --
- *
- * Take a ``region'' which is a non-y-x-banded random collection of
- * rectangles, and compute a nice region which is the union of all the
- * rectangles.
- *
- * Results:
- * TRUE if successful.
- *
- * Side Effects:
- * The passed-in ``region'' may be modified.
- * pOverlap set to TRUE if any retangles overlapped, else FALSE;
- *
- * Strategy:
- * Step 1. Sort the rectangles into ascending order with primary key y1
- * and secondary key x1.
- *
- * Step 2. Split the rectangles into the minimum number of proper y-x
- * banded regions. This may require horizontally merging
- * rectangles, and vertically coalescing bands. With any luck,
- * this step in an identity tranformation (ala the Box widget),
- * or a coalescing into 1 box (ala Menus).
- *
- * Step 3. Merge the separate regions down to a single region by calling
- * miUnion. Maximize the work each miUnion call does by using
- * a binary merge.
- *
- *-----------------------------------------------------------------------
- */
- Bool
- miRegionValidate(badreg, pOverlap)
- RegionPtr badreg;
- Bool *pOverlap;
- {
- /* Descriptor for regions under construction in Step 2. */
- typedef struct {
- RegionRec reg;
- int prevBand;
- int curBand;
- } RegionInfo;
- int numRects; /* Original numRects for badreg */
- RegionInfo *ri; /* Array of current regions */
- int numRI; /* Number of entries used in ri */
- int sizeRI; /* Number of entries available in ri */
- int i; /* Index into rects */
- register int j; /* Index into ri */
- register RegionInfo *rit; /* &ri[j] */
- register RegionPtr reg; /* ri[j].reg */
- register BoxPtr box; /* Current box in rects */
- register BoxPtr riBox; /* Last box in ri[j].reg */
- register RegionPtr hreg; /* ri[j_half].reg */
- Bool ret = TRUE;
- *pOverlap = FALSE;
- if (!badreg->data)
- {
- good(badreg);
- return TRUE;
- }
- numRects = badreg->data->numRects;
- if (!numRects)
- {
- if (REGION_NAR(badreg))
- return FALSE;
- good(badreg);
- return TRUE;
- }
- if (badreg->extents.x1 < badreg->extents.x2)
- {
- if ((numRects) == 1)
- {
- xfreeData(badreg);
- badreg->data = (RegDataPtr) NULL;
- }
- else
- {
- DOWNSIZE(badreg, numRects);
- }
- good(badreg);
- return TRUE;
- }
- /* Step 1: Sort the rects array into ascending (y1, x1) order */
- QuickSortRects(REGION_BOXPTR(badreg), numRects);
- /* Step 2: Scatter the sorted array into the minimum number of regions */
- /* Set up the first region to be the first rectangle in badreg */
- /* Note that step 2 code will never overflow the ri[0].reg rects array */
- ri = (RegionInfo *) xalloc(4 * sizeof(RegionInfo));
- if (!ri)
- return miRegionBreak (badreg);
- sizeRI = 4;
- numRI = 1;
- ri[0].prevBand = 0;
- ri[0].curBand = 0;
- ri[0].reg = *badreg;
- box = REGION_BOXPTR(&ri[0].reg);
- ri[0].reg.extents = *box;
- ri[0].reg.data->numRects = 1;
- /* Now scatter rectangles into the minimum set of valid regions. If the
- next rectangle to be added to a region would force an existing rectangle
- in the region to be split up in order to maintain y-x banding, just
- forget it. Try the next region. If it doesn't fit cleanly into any
- region, make a new one. */
- for (i = numRects; --i > 0;)
- {
- box++;
- /* Look for a region to append box to */
- for (j = numRI, rit = ri; --j >= 0; rit++)
- {
- reg = &rit->reg;
- riBox = REGION_END(reg);
- if (box->y1 == riBox->y1 && box->y2 == riBox->y2)
- {
- /* box is in same band as riBox. Merge or append it */
- if (box->x1 <= riBox->x2)
- {
- /* Merge it with riBox */
- if (box->x1 < riBox->x2) *pOverlap = TRUE;
- if (box->x2 > riBox->x2) riBox->x2 = box->x2;
- }
- else
- {
- RECTALLOC_BAIL(reg, 1, bail);
- *REGION_TOP(reg) = *box;
- reg->data->numRects++;
- }
- goto NextRect; /* So sue me */
- }
- else if (box->y1 >= riBox->y2)
- {
- /* Put box into new band */
- if (reg->extents.x2 < riBox->x2) reg->extents.x2 = riBox->x2;
- if (reg->extents.x1 > box->x1) reg->extents.x1 = box->x1;
- Coalesce(reg, rit->prevBand, rit->curBand);
- rit->curBand = reg->data->numRects;
- RECTALLOC_BAIL(reg, 1, bail);
- *REGION_TOP(reg) = *box;
- reg->data->numRects++;
- goto NextRect;
- }
- /* Well, this region was inappropriate. Try the next one. */
- } /* for j */
- /* Uh-oh. No regions were appropriate. Create a new one. */
- if (sizeRI == numRI)
- {
- /* Oops, allocate space for new region information */
- sizeRI <<= 1;
- rit = (RegionInfo *) xrealloc(ri, sizeRI * sizeof(RegionInfo));
- if (!rit)
- goto bail;
- ri = rit;
- rit = &ri[numRI];
- }
- numRI++;
- rit->prevBand = 0;
- rit->curBand = 0;
- rit->reg.extents = *box;
- rit->reg.data = (RegDataPtr)NULL;
- if (!miRectAlloc(&rit->reg, (i+numRI) / numRI)) /* MUST force allocation */
- goto bail;
- NextRect: ;
- } /* for i */
- /* Make a final pass over each region in order to Coalesce and set
- extents.x2 and extents.y2 */
- for (j = numRI, rit = ri; --j >= 0; rit++)
- {
- reg = &rit->reg;
- riBox = REGION_END(reg);
- reg->extents.y2 = riBox->y2;
- if (reg->extents.x2 < riBox->x2) reg->extents.x2 = riBox->x2;
- Coalesce(reg, rit->prevBand, rit->curBand);
- if (reg->data->numRects == 1) /* keep unions happy below */
- {
- xfreeData(reg);
- reg->data = (RegDataPtr)NULL;
- }
- }
- /* Step 3: Union all regions into a single region */
- while (numRI > 1)
- {
- int half = numRI/2;
- for (j = numRI & 1; j < (half + (numRI & 1)); j++)
- {
- reg = &ri[j].reg;
- hreg = &ri[j+half].reg;
- if (!miRegionOp(reg, reg, hreg, miUnionO, TRUE, TRUE, pOverlap))
- ret = FALSE;
- if (hreg->extents.x1 < reg->extents.x1)
- reg->extents.x1 = hreg->extents.x1;
- if (hreg->extents.y1 < reg->extents.y1)
- reg->extents.y1 = hreg->extents.y1;
- if (hreg->extents.x2 > reg->extents.x2)
- reg->extents.x2 = hreg->extents.x2;
- if (hreg->extents.y2 > reg->extents.y2)
- reg->extents.y2 = hreg->extents.y2;
- xfreeData(hreg);
- }
- numRI -= half;
- }
- *badreg = ri[0].reg;
- xfree(ri);
- good(badreg);
- return ret;
- bail:
- for (i = 0; i < numRI; i++)
- xfreeData(&ri[i].reg);
- xfree (ri);
- return miRegionBreak (badreg);
- }
- RegionPtr
- miRectsToRegion(nrects, prect, ctype)
- int nrects;
- register xRectangle *prect;
- int ctype;
- {
- register RegionPtr pRgn;
- register RegDataPtr pData;
- register BoxPtr pBox;
- register int i;
- int x1, y1, x2, y2;
- pRgn = miRegionCreate(NullBox, 0);
- if (REGION_NAR (pRgn))
- return pRgn;
- if (!nrects)
- return pRgn;
- if (nrects == 1)
- {
- x1 = prect->x;
- y1 = prect->y;
- if ((x2 = x1 + (int) prect->width) > MAXSHORT)
- x2 = MAXSHORT;
- if ((y2 = y1 + (int) prect->height) > MAXSHORT)
- y2 = MAXSHORT;
- if (x1 != x2 && y1 != y2)
- {
- pRgn->extents.x1 = x1;
- pRgn->extents.y1 = y1;
- pRgn->extents.x2 = x2;
- pRgn->extents.y2 = y2;
- pRgn->data = (RegDataPtr)NULL;
- }
- return pRgn;
- }
- pData = xallocData(nrects);
- if (!pData)
- {
- miRegionBreak (pRgn);
- return pRgn;
- }
- pBox = (BoxPtr) (pData + 1);
- for (i = nrects; --i >= 0; prect++)
- {
- x1 = prect->x;
- y1 = prect->y;
- if ((x2 = x1 + (int) prect->width) > MAXSHORT)
- x2 = MAXSHORT;
- if ((y2 = y1 + (int) prect->height) > MAXSHORT)
- y2 = MAXSHORT;
- if (x1 != x2 && y1 != y2)
- {
- pBox->x1 = x1;
- pBox->y1 = y1;
- pBox->x2 = x2;
- pBox->y2 = y2;
- pBox++;
- }
- }
- if (pBox != (BoxPtr) (pData + 1))
- {
- pData->size = nrects;
- pData->numRects = pBox - (BoxPtr) (pData + 1);
- pRgn->data = pData;
- if (ctype != CT_YXBANDED)
- {
- Bool overlap; /* result ignored */
- pRgn->extents.x1 = pRgn->extents.x2 = 0;
- miRegionValidate(pRgn, &overlap);
- }
- else
- miSetExtents(pRgn);
- good(pRgn);
- }
- else
- {
- xfree (pData);
- }
- return pRgn;
- }
- /*======================================================================
- * Region Subtraction
- *====================================================================*/
- /*-
- *-----------------------------------------------------------------------
- * miSubtractO --
- * Overlapping band subtraction. x1 is the left-most point not yet
- * checked.
- *
- * Results:
- * TRUE if successful.
- *
- * Side Effects:
- * pReg may have rectangles added to it.
- *
- *-----------------------------------------------------------------------
- */
- /*ARGSUSED*/
- static Bool
- miSubtractO (
- register RegionPtr pReg,
- register BoxPtr r1,
- BoxPtr r1End,
- register BoxPtr r2,
- BoxPtr r2End,
- register short y1,
- short y2,
- Bool *pOverlap)
- {
- register BoxPtr pNextRect;
- register int x1;
- x1 = r1->x1;
-
- assert(y1<y2);
- assert(r1 != r1End && r2 != r2End);
- pNextRect = REGION_TOP(pReg);
- do
- {
- if (r2->x2 <= x1)
- {
- /*
- * Subtrahend entirely to left of minuend: go to next subtrahend.
- */
- r2++;
- }
- else if (r2->x1 <= x1)
- {
- /*
- * Subtrahend preceeds minuend: nuke left edge of minuend.
- */
- x1 = r2->x2;
-