527 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			527 lines
		
	
	
		
			18 KiB
		
	
	
	
		
			C
		
	
	
	
/***********************************************************
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Copyright 1989, 1998  The Open Group
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Permission to use, copy, modify, distribute, and sell this software and its
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documentation for any purpose is hereby granted without fee, provided that
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the above copyright notice appear in all copies and that both that
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copyright notice and this permission notice appear in supporting
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documentation.
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The above copyright notice and this permission notice shall be included in
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all copies or substantial portions of the Software.
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THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
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OPEN GROUP BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
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AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
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CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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Except as contained in this notice, the name of The Open Group shall not be
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used in advertising or otherwise to promote the sale, use or other dealings
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in this Software without prior written authorization from The Open Group.
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Copyright 1989 by Digital Equipment Corporation, Maynard, Massachusetts.
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                        All Rights Reserved
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Permission to use, copy, modify, and distribute this software and its 
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documentation for any purpose and without fee is hereby granted, 
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provided that the above copyright notice appear in all copies and that
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both that copyright notice and this permission notice appear in 
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supporting documentation, and that the name of Digital not be
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used in advertising or publicity pertaining to distribution of the
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software without specific, written prior permission.  
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DIGITAL DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
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ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
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DIGITAL BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
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ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
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WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
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ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
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SOFTWARE.
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******************************************************************/
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#ifdef HAVE_DIX_CONFIG_H
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#include <dix-config.h>
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#endif
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#include "misc.h"
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#include "pixmapstr.h"
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#include "gcstruct.h"
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#include "mispans.h"
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/*
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These routines maintain lists of Spans, in order to implement the
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``touch-each-pixel-once'' rules of wide lines and arcs.
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Written by Joel McCormack, Summer 1989.
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*/
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void
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miInitSpanGroup(SpanGroup * spanGroup)
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{
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    spanGroup->size = 0;
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    spanGroup->count = 0;
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    spanGroup->group = NULL;
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    spanGroup->ymin = MAXSHORT;
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    spanGroup->ymax = MINSHORT;
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}                               /* InitSpanGroup */
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#define YMIN(spans) (spans->points[0].y)
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#define YMAX(spans)  (spans->points[spans->count-1].y)
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static void
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miSubtractSpans(SpanGroup * spanGroup, Spans * sub)
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{
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    int i, subCount, spansCount;
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    int ymin, ymax, xmin, xmax;
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    Spans *spans;
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    DDXPointPtr subPt, spansPt;
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    int *subWid, *spansWid;
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    int extra;
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    ymin = YMIN(sub);
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    ymax = YMAX(sub);
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    spans = spanGroup->group;
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    for (i = spanGroup->count; i; i--, spans++) {
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        if (YMIN(spans) <= ymax && ymin <= YMAX(spans)) {
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            subCount = sub->count;
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            subPt = sub->points;
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            subWid = sub->widths;
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            spansCount = spans->count;
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            spansPt = spans->points;
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            spansWid = spans->widths;
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            extra = 0;
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            for (;;) {
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                while (spansCount && spansPt->y < subPt->y) {
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                    spansPt++;
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                    spansWid++;
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                    spansCount--;
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                }
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                if (!spansCount)
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                    break;
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                while (subCount && subPt->y < spansPt->y) {
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                    subPt++;
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                    subWid++;
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                    subCount--;
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                }
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                if (!subCount)
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                    break;
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                if (subPt->y == spansPt->y) {
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                    xmin = subPt->x;
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                    xmax = xmin + *subWid;
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                    if (xmin >= spansPt->x + *spansWid || spansPt->x >= xmax) {
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                        ;
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                    }
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                    else if (xmin <= spansPt->x) {
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                        if (xmax >= spansPt->x + *spansWid) {
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                            memmove(spansPt, spansPt + 1,
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                                    sizeof *spansPt * (spansCount - 1));
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                            memmove(spansWid, spansWid + 1,
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                                    sizeof *spansWid * (spansCount - 1));
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                            spansPt--;
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                            spansWid--;
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                            spans->count--;
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                            extra++;
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                        }
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                        else {
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                            *spansWid = *spansWid - (xmax - spansPt->x);
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                            spansPt->x = xmax;
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                        }
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                    }
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                    else {
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                        if (xmax >= spansPt->x + *spansWid) {
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                            *spansWid = xmin - spansPt->x;
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                        }
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                        else {
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                            if (!extra) {
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                                DDXPointPtr newPt;
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                                int *newwid;
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#define EXTRA 8
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                                newPt =
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                                    (DDXPointPtr) realloc(spans->points,
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                                                          (spans->count +
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                                                           EXTRA) *
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                                                          sizeof(DDXPointRec));
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                                if (!newPt)
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                                    break;
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                                spansPt = newPt + (spansPt - spans->points);
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                                spans->points = newPt;
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                                newwid =
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                                    (int *) realloc(spans->widths,
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                                                    (spans->count +
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                                                     EXTRA) * sizeof(int));
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                                if (!newwid)
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                                    break;
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                                spansWid = newwid + (spansWid - spans->widths);
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                                spans->widths = newwid;
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                                extra = EXTRA;
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                            }
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                            memmove(spansPt + 1, spansPt,
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                                    sizeof *spansPt * (spansCount));
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                            memmove(spansWid + 1, spansWid,
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                                    sizeof *spansWid * (spansCount));
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                            spans->count++;
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                            extra--;
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                            *spansWid = xmin - spansPt->x;
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                            spansWid++;
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                            spansPt++;
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                            *spansWid = *spansWid - (xmax - spansPt->x);
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                            spansPt->x = xmax;
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                        }
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                    }
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                }
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                spansPt++;
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                spansWid++;
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                spansCount--;
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            }
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        }
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    }
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}
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void
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miAppendSpans(SpanGroup * spanGroup, SpanGroup * otherGroup, Spans * spans)
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{
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    int ymin, ymax;
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    int spansCount;
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    spansCount = spans->count;
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    if (spansCount > 0) {
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        if (spanGroup->size == spanGroup->count) {
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            spanGroup->size = (spanGroup->size + 8) * 2;
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            spanGroup->group = (Spans *)
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                realloc(spanGroup->group, sizeof(Spans) * spanGroup->size);
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        }
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        spanGroup->group[spanGroup->count] = *spans;
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        (spanGroup->count)++;
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        ymin = spans->points[0].y;
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        if (ymin < spanGroup->ymin)
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            spanGroup->ymin = ymin;
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        ymax = spans->points[spansCount - 1].y;
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        if (ymax > spanGroup->ymax)
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            spanGroup->ymax = ymax;
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        if (otherGroup && otherGroup->ymin < ymax && ymin < otherGroup->ymax) {
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            miSubtractSpans(otherGroup, spans);
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        }
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    }
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    else {
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        free(spans->points);
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        free(spans->widths);
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    }
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}                               /* AppendSpans */
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void
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miFreeSpanGroup(SpanGroup * spanGroup)
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{
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    free(spanGroup->group);
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}
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static void
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QuickSortSpansX(DDXPointRec points[], int widths[], int numSpans)
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{
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    int x;
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    int i, j, m;
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    DDXPointPtr r;
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/* Always called with numSpans > 1 */
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/* Sorts only by x, as all y should be the same */
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#define ExchangeSpans(a, b)				    \
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{							    \
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    DDXPointRec 	tpt;				    \
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    int    		tw;				    \
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							    \
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    tpt = points[a]; points[a] = points[b]; points[b] = tpt;    \
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    tw = widths[a]; widths[a] = widths[b]; widths[b] = tw;  \
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}
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    do {
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        if (numSpans < 9) {
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            /* Do insertion sort */
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            int xprev;
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            xprev = points[0].x;
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            i = 1;
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            do {                /* while i != numSpans */
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                x = points[i].x;
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                if (xprev > x) {
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                    /* points[i] is out of order.  Move into proper location. */
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                    DDXPointRec tpt;
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                    int tw, k;
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                    for (j = 0; x >= points[j].x; j++) {
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                    }
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                    tpt = points[i];
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                    tw = widths[i];
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                    for (k = i; k != j; k--) {
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                        points[k] = points[k - 1];
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                        widths[k] = widths[k - 1];
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                    }
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                    points[j] = tpt;
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                    widths[j] = tw;
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                    x = points[i].x;
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                }               /* if out of order */
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                xprev = x;
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                i++;
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            } while (i != numSpans);
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            return;
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        }
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        /* Choose partition element, stick in location 0 */
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        m = numSpans / 2;
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        if (points[m].x > points[0].x)
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            ExchangeSpans(m, 0);
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        if (points[m].x > points[numSpans - 1].x)
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            ExchangeSpans(m, numSpans - 1);
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        if (points[m].x > points[0].x)
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            ExchangeSpans(m, 0);
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        x = points[0].x;
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        /* Partition array */
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        i = 0;
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        j = numSpans;
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        do {
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            r = &(points[i]);
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            do {
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                r++;
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                i++;
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            } while (i != numSpans && r->x < x);
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            r = &(points[j]);
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            do {
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                r--;
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                j--;
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            } while (x < r->x);
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            if (i < j)
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                ExchangeSpans(i, j);
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        } while (i < j);
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        /* Move partition element back to middle */
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        ExchangeSpans(0, j);
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        /* Recurse */
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        if (numSpans - j - 1 > 1)
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            QuickSortSpansX(&points[j + 1], &widths[j + 1], numSpans - j - 1);
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        numSpans = j;
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    } while (numSpans > 1);
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}                               /* QuickSortSpans */
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static int
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UniquifySpansX(Spans * spans, DDXPointRec * newPoints, int *newWidths)
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{
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    int newx1, newx2, oldpt, i, y;
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    DDXPointRec *oldPoints;
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    int *oldWidths;
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    int *startNewWidths;
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/* Always called with numSpans > 1 */
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/* Uniquify the spans, and stash them into newPoints and newWidths.  Return the
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   number of unique spans. */
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    startNewWidths = newWidths;
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    oldPoints = spans->points;
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    oldWidths = spans->widths;
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    y = oldPoints->y;
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    newx1 = oldPoints->x;
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    newx2 = newx1 + *oldWidths;
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    for (i = spans->count - 1; i != 0; i--) {
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        oldPoints++;
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        oldWidths++;
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        oldpt = oldPoints->x;
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        if (oldpt > newx2) {
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            /* Write current span, start a new one */
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            newPoints->x = newx1;
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            newPoints->y = y;
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            *newWidths = newx2 - newx1;
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            newPoints++;
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            newWidths++;
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            newx1 = oldpt;
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            newx2 = oldpt + *oldWidths;
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        }
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        else {
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            /* extend current span, if old extends beyond new */
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            oldpt = oldpt + *oldWidths;
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            if (oldpt > newx2)
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                newx2 = oldpt;
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        }
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    }                           /* for */
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    /* Write final span */
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    newPoints->x = newx1;
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    *newWidths = newx2 - newx1;
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    newPoints->y = y;
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    return (newWidths - startNewWidths) + 1;
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}                               /* UniquifySpansX */
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static void
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miDisposeSpanGroup(SpanGroup * spanGroup)
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{
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    int i;
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    Spans *spans;
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    for (i = 0; i < spanGroup->count; i++) {
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        spans = spanGroup->group + i;
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        free(spans->points);
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        free(spans->widths);
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    }
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}
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void
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miFillUniqueSpanGroup(DrawablePtr pDraw, GCPtr pGC, SpanGroup * spanGroup)
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{
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    int i;
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    Spans *spans;
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    Spans *yspans;
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    int *ysizes;
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    int ymin, ylength;
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    /* Outgoing spans for one big call to FillSpans */
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    DDXPointPtr points;
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    int *widths;
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    int count;
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    if (spanGroup->count == 0)
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        return;
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    if (spanGroup->count == 1) {
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        /* Already should be sorted, unique */
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        spans = spanGroup->group;
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        (*pGC->ops->FillSpans)
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            (pDraw, pGC, spans->count, spans->points, spans->widths, TRUE);
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        free(spans->points);
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        free(spans->widths);
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    }
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    else {
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        /* Yuck.  Gross.  Radix sort into y buckets, then sort x and uniquify */
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        /* This seems to be the fastest thing to do.  I've tried sorting on
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           both x and y at the same time rather than creating into all those
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           y buckets, but it was somewhat slower. */
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        ymin = spanGroup->ymin;
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        ylength = spanGroup->ymax - ymin + 1;
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        /* Allocate Spans for y buckets */
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        yspans = malloc(ylength * sizeof(Spans));
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        ysizes = malloc(ylength * sizeof(int));
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        if (!yspans || !ysizes) {
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            free(yspans);
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            free(ysizes);
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            miDisposeSpanGroup(spanGroup);
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            return;
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        }
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        for (i = 0; i != ylength; i++) {
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            ysizes[i] = 0;
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            yspans[i].count = 0;
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            yspans[i].points = NULL;
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            yspans[i].widths = NULL;
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        }
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        /* Go through every single span and put it into the correct bucket */
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        count = 0;
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        for (i = 0, spans = spanGroup->group;
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             i != spanGroup->count; i++, spans++) {
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            int index;
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            int j;
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            for (j = 0, points = spans->points, widths = spans->widths;
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                 j != spans->count; j++, points++, widths++) {
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                index = points->y - ymin;
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                if (index >= 0 && index < ylength) {
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                    Spans *newspans = &(yspans[index]);
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                    if (newspans->count == ysizes[index]) {
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                        DDXPointPtr newpoints;
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                        int *newwidths;
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                        ysizes[index] = (ysizes[index] + 8) * 2;
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                        newpoints = (DDXPointPtr) realloc(newspans->points,
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                                                          ysizes[index] *
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                                                          sizeof(DDXPointRec));
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                        newwidths =
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                            (int *) realloc(newspans->widths,
 | 
						|
                                            ysizes[index] * sizeof(int));
 | 
						|
                        if (!newpoints || !newwidths) {
 | 
						|
                            for (i = 0; i < ylength; i++) {
 | 
						|
                                free(yspans[i].points);
 | 
						|
                                free(yspans[i].widths);
 | 
						|
                            }
 | 
						|
                            free(yspans);
 | 
						|
                            free(ysizes);
 | 
						|
                            free(newpoints);
 | 
						|
                            free(newwidths);
 | 
						|
                            miDisposeSpanGroup(spanGroup);
 | 
						|
                            return;
 | 
						|
                        }
 | 
						|
                        newspans->points = newpoints;
 | 
						|
                        newspans->widths = newwidths;
 | 
						|
                    }
 | 
						|
                    newspans->points[newspans->count] = *points;
 | 
						|
                    newspans->widths[newspans->count] = *widths;
 | 
						|
                    (newspans->count)++;
 | 
						|
                }               /* if y value of span in range */
 | 
						|
            }                   /* for j through spans */
 | 
						|
            count += spans->count;
 | 
						|
            free(spans->points);
 | 
						|
            spans->points = NULL;
 | 
						|
            free(spans->widths);
 | 
						|
            spans->widths = NULL;
 | 
						|
        }                       /* for i thorough Spans */
 | 
						|
 | 
						|
        /* Now sort by x and uniquify each bucket into the final array */
 | 
						|
        points = malloc(count * sizeof(DDXPointRec));
 | 
						|
        widths = malloc(count * sizeof(int));
 | 
						|
        if (!points || !widths) {
 | 
						|
            for (i = 0; i < ylength; i++) {
 | 
						|
                free(yspans[i].points);
 | 
						|
                free(yspans[i].widths);
 | 
						|
            }
 | 
						|
            free(yspans);
 | 
						|
            free(ysizes);
 | 
						|
            free(points);
 | 
						|
            free(widths);
 | 
						|
            return;
 | 
						|
        }
 | 
						|
        count = 0;
 | 
						|
        for (i = 0; i != ylength; i++) {
 | 
						|
            int ycount = yspans[i].count;
 | 
						|
 | 
						|
            if (ycount > 0) {
 | 
						|
                if (ycount > 1) {
 | 
						|
                    QuickSortSpansX(yspans[i].points, yspans[i].widths, ycount);
 | 
						|
                    count += UniquifySpansX
 | 
						|
                        (&(yspans[i]), &(points[count]), &(widths[count]));
 | 
						|
                }
 | 
						|
                else {
 | 
						|
                    points[count] = yspans[i].points[0];
 | 
						|
                    widths[count] = yspans[i].widths[0];
 | 
						|
                    count++;
 | 
						|
                }
 | 
						|
                free(yspans[i].points);
 | 
						|
                free(yspans[i].widths);
 | 
						|
            }
 | 
						|
        }
 | 
						|
 | 
						|
        (*pGC->ops->FillSpans) (pDraw, pGC, count, points, widths, TRUE);
 | 
						|
        free(points);
 | 
						|
        free(widths);
 | 
						|
        free(yspans);
 | 
						|
        free(ysizes);           /* use (DE)xalloc for these? */
 | 
						|
    }
 | 
						|
 | 
						|
    spanGroup->count = 0;
 | 
						|
    spanGroup->ymin = MAXSHORT;
 | 
						|
    spanGroup->ymax = MINSHORT;
 | 
						|
}
 |