X-Git-Url: https://git.sesse.net/?p=rdpsrv;a=blobdiff_plain;f=Xserver%2Flib%2Ffont%2FType1%2Fregions.c;fp=Xserver%2Flib%2Ffont%2FType1%2Fregions.c;h=c9b0038aa0ed6e74a8e3b40ef614b21be393b9a8;hp=0000000000000000000000000000000000000000;hb=b6e6afccf37f4ad0515ef2a698f714fdf1bf23b3;hpb=e3340a110a3b01756b8e67531395a33b40a17d37 diff --git a/Xserver/lib/font/Type1/regions.c b/Xserver/lib/font/Type1/regions.c new file mode 100644 index 0000000..c9b0038 --- /dev/null +++ b/Xserver/lib/font/Type1/regions.c @@ -0,0 +1,1746 @@ +/* $XConsortium: regions.c,v 1.6 94/02/06 16:22:21 gildea Exp $ */ +/* $XFree86: xc/lib/font/Type1/regions.c,v 3.0 1996/08/25 13:58:26 dawes Exp $ */ +/* Copyright International Business Machines, Corp. 1991 + * All Rights Reserved + * Copyright Lexmark International, Inc. 1991 + * All Rights Reserved + * + * License 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 IBM or Lexmark not be + * used in advertising or publicity pertaining to distribution of the + * software without specific, written prior permission. + * + * IBM AND LEXMARK PROVIDE THIS SOFTWARE "AS IS", WITHOUT ANY WARRANTIES OF + * ANY KIND, EITHER EXPRESS OR IMPLIED, INCLUDING, BUT NOT LIMITED TO ANY + * IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, + * AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. THE ENTIRE RISK AS TO THE + * QUALITY AND PERFORMANCE OF THE SOFTWARE, INCLUDING ANY DUTY TO SUPPORT + * OR MAINTAIN, BELONGS TO THE LICENSEE. SHOULD ANY PORTION OF THE + * SOFTWARE PROVE DEFECTIVE, THE LICENSEE (NOT IBM OR LEXMARK) ASSUMES THE + * ENTIRE COST OF ALL SERVICING, REPAIR AND CORRECTION. IN NO EVENT SHALL + * IBM OR LEXMARK 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. + */ + /* REGIONS CWEB V0023 LOTS */ +/* +:h1 id=regions.REGIONS Module - Regions Operator Handler + +This module is responsible for creating and manipulating regions. + +&author. Jeffrey B. Lotspiech (lotspiech@almaden.ibm.com) + + +:h3.Include Files + +The included files are: +*/ + +#include "objects.h" +#include "spaces.h" +#include "regions.h" +#include "paths.h" +#include "curves.h" +#include "lines.h" +#include "pictures.h" +#include "fonts.h" +#include "hints.h" +#include "strokes.h" /* to pick up 'DoStroke' */ +static Unwind(); +static void newfilledge(); +static struct edgelist *splitedge(); +static void vertjoin(); +static int touches(); +static int crosses(); +static void edgemin(); +static void edgemax(); +static discard(); +static edgecheck(); +static struct edgelist *NewEdge(); +static struct edgelist *swathxsort(); /* 'SortSwath' function */ + +/* +:h3.Functions Provided to the TYPE1IMAGER User + +This module provides the following TYPE1IMAGER entry points: +*/ + +/*SHARED LINE(S) ORIGINATED HERE*/ +/* +:h3.Functions Provided to Other Modules + +This module provides the following entry points to other modules: +*/ + +/*SHARED LINE(S) ORIGINATED HERE*/ +/* +:h3.Macros Provided to Other Modules + +:h4.GOING_TO() - Macro Predicate Needed for Changing Direction, Etc. + +The actual generation of run end lists (edge boundaries) is left +to the low level rasterizing modules, LINES and CURVES. There +are some global region-type +questions that occur when doing a low-level +rasterization: +:ol. +:li.Did we just change direction in Y and therefore need to start +a new edge? +:li.Did we run out of allocated edge space? +:li.Do the minimum or maximum X values for the current edge need +updating? +:eol. +In general the REGIONS is not smart enough to answer those questions +itself. (For example, determining if and when a curve changes direction +may need detailed curve knowledge.) Yet, this must be done efficiently. +We provide a macro "GOING_TO" where the invoker tells us where it is +heading for (x2,y2), plus where it is now (x1,y1), plus the current +region under construction, and the macro answers the questions above. +*/ + +/*SHARED LINE(S) ORIGINATED HERE*/ +/* +:h2.Data Structures Used to Represent Regions + +:h3.The "region" Structure + +The region structure is an anchor for a linked list of "edgelist" +structures (see :hdref refid=edgelist..). It also summarizes the +information in the edgelist structures (for example, the bounding +box of the region). And, it contains scratch areas used during +the creation of a region. +*/ + +/*SHARED LINE(S) ORIGINATED HERE*/ +/* +The ISOPTIMIZED flag tells us if we've put a permanent region in +'optimal' form. +*/ +#define ISOPTIMIZED(flag) ((flag)&0x10) + +/* +The ISRECTANGULAR flag tells us if a region is a rectangle. We don't +always notice rectangles--if this flag is set, the region definitely +is a rectangle, but some rectangular regions will not have the flag +set. The flag is used to optimize some paths. +*/ + +/*SHARED LINE(S) ORIGINATED HERE*/ +/* +:h4."INFINITY" - A Constant Region Structure of Infinite Extent + +Infinity is the complement of a null area: +Note - removed the refcount = 1 init, replaced with references = 2 3-26-91 PNM +*/ +static struct region infinity = { REGIONTYPE, + ISCOMPLEMENT(ON)+ISINFINITE(ON)+ISPERMANENT(ON)+ISIMMORTAL(ON), 2, + 0, 0, 0, 0, + 0, 0, 0, 0, + NULL, NULL, + 0, 0, 0, 0, 0, NULL, NULL, + NULL, 0, NULL, NULL }; +struct region *INFINITY = &infinity; + +/* +:h4."EmptyRegion" - A Region Structure with Zero Area + +This structure is used to initialize the region to be built in +Interior(): +Note - replaced refcount = 1 init with references = 2 3-26-91 PNM +*/ + +/*SHARED LINE(S) ORIGINATED HERE*/ +struct region EmptyRegion = { REGIONTYPE, + ISPERMANENT(ON)+ISIMMORTAL(ON), 2, + 0, 0, 0, 0, + MAXPEL, MAXPEL, MINPEL, MINPEL, + NULL, NULL, + 0, 0, 0, 0, 0, NULL, NULL, + NULL, 0, NULL, NULL }; + +/* +:h3 id=edgelist.The "edgelist" Structure + +Regions are represented by a linked list of 'edgelist' structures. +When a region is complete, the structures are paired, one for the +left and one for the right edge. While a region is being built, +this rule may be violated temporarily. + +An 'edgelist' structure contains the X values for a given span +of Y values. The (X,Y) pairs define an edge. We use the crack +and edge coordinate system, so that integer values of X and Y +go between pels. The edge is defined between the minimum Y and +maximum Y. + +The linked list is kept sorted from top to bottom, that is, in +increasing y. Also, if 'e1' is an edgelist structure and 'e2' is the +next one in the list, they must have exactly the same ymin,ymax values +or be totally disjoint. These two requirements mean that if e2's ymin +is less than e1's ymax, it must be exactly equal to e1's ymin. A +sublist of structures with identical ymin and ymax values is called a +'swath'. + +In addition, edgelist structures are separately linked together based +on what subpath originally created them; each subpath is kept as a +separate circular linked list. This information is ignored unless +continuity checking is invoked. See :hdref refid=subpath. for a +complete description of this. +*/ + + +/*SHARED LINE(S) ORIGINATED HERE*/ + +/* +The "edgelist" structure follows the convention of TYPE1IMAGER user +objects, having a type field and a flag field as the first two +elements. However, the user never sees "edgelist" structures +directly; he is given handles to "region" structures only. + +By having a type field, we can use the "copy" feature of Allocate() +to duplicate edge lists quickly. + +We also define two flag bits for this structure. The ISDOWN bit is set +if the edge is going in the direction of increasing Y. The ISAMBIGUOUS +bit is set if the edge is identical to its neighbor (edge->link); such +edges may be "left" when they should be "right", or vice versa, +unnecessarily confusing the continuity checking logic. The FixSubPaths() +routine in HINTS will swap ambiguous edges if that avoids crossing edges; +see :hdref refid=fixsubp.. +*/ + +/*SHARED LINE(S) ORIGINATED HERE*/ + +/* +:h3.KillRegion() - Destroys a Region + +KillRegion nominally just decrements the reference count to that region. +If the reference count becomes 0, all memory associated with it is +freed. We just follow the linked list, freeing as we go, then kill any +associated (thresholded) picture. +Note - added conditional return based on references 3-26-91 PNM +*/ + +void KillRegion(area) + register struct region *area; /* area to free */ +{ + register struct edgelist *p; /* loop variable */ + register struct edgelist *next; /* loop variable */ + + if (area->references < 0) + abort("KillRegion: negative reference count"); + if ( (--(area->references) > 1) || + ( (area->references == 1) && !ISPERMANENT(area->flag) ) ) + return; + + for (p=area->anchor; p != NULL; p=next) { + next = p->link; + Free(p); + } + if (area->thresholded != NULL) + KillPicture(area->thresholded); + Free(area); +} +/* +:h3.CopyRegion() - Makes a Copy of a Region +*/ +struct region *CopyRegion(area) + register struct region *area; /* region to duplicate */ +{ + register struct region *r; /* output region built here */ + register struct edgelist *last; /* loop variable */ + register struct edgelist *p,*newp; /* loop variables */ + + r = (struct region *)Allocate(sizeof(struct region), area, 0); + r->anchor = NULL; + + for (p=area->anchor; VALIDEDGE(p); p=p->link) { + + newp = NewEdge(p->xmin, p->xmax, p->ymin, p->ymax, p->xvalues, ISDOWN(p->flag)); + if (r->anchor == NULL) + r->anchor = last = newp; + else + last->link = newp; + + last = newp; + } + if (area->thresholded != NULL) + /* replaced DupPicture with Dup() 3-26-91 PNM */ + r->thresholded = (struct picture *)Dup(area->thresholded); + return(r); +} +/* +:h4.NewEdge() - Allocates and Returns a New "edgelist" Structure + +We allocate space for the X values contiguously with the 'edgelist' +structure that locates them. That way, we only have to free the +edgelist structure to free all memory associated with it. Damn +clever, huh? +*/ + +static struct edgelist *NewEdge(xmin, xmax, ymin, ymax, xvalues, isdown) + pel xmin,xmax; /* X extent of edge */ + pel ymin,ymax; /* Y extent of edge */ + pel *xvalues; /* list of X values for entire edge */ + int isdown; /* flag: TRUE means edge progresses downward */ +{ + static struct edgelist template = { + EDGETYPE, 0, 1, NULL, NULL, + 0, 0, 0, 0, NULL }; + + register struct edgelist *r; /* returned structure */ + register int iy; /* ymin adjusted for 'long' alignment purposes */ + + IfTrace2((RegionDebug),"....new edge: ymin=%d, ymax=%d ", + (long)ymin, (long) ymax); + if (ymin >= ymax) + abort("newedge: height not positive"); +/* +We are going to copy the xvalues into a newly allocated area. It +helps performance if the values are all "long" aligned. We can test +if the xvalues are long aligned by ANDing the address with the +(sizeof(long) - 1)--if non zero, the xvalues are not aligned well. We +set 'iy' to the ymin value that would give us good alignment: +*/ + iy = ymin - (((unsigned long)xvalues) & (sizeof(long)-1)) / sizeof(pel); + + r = (struct edgelist *)Allocate(sizeof(struct edgelist), &template, + (ymax - iy) * sizeof(pel)); + + if (isdown) r->flag = ISDOWN(ON); + r->xmin = xmin; + r->xmax = xmax; + r->ymin = ymin; + r->ymax = ymax; + + r->xvalues = (pel *) FOLLOWING(r); + if (ymin != iy) { + r->xvalues += ymin - iy; + xvalues -= ymin - iy; + } + +/* +We must round up (ymax - iy) so we get the ceiling of the number of +longs. The destination must be able to hold these extra bytes because +Allocate() makes everything it allocates be in multiples of longs. +*/ + LONGCOPY(&r[1], xvalues, (ymax - iy) * sizeof(pel) + sizeof(long) - 1); + + IfTrace1((RegionDebug),"result=%x\n", r); + return(r); +} + +/* +:h2.Building Regions + +:h3.Interior() - Iterate Through a Path, Building a Region + +This routine is the workhorse driver routine that iterates through a +path, calling the appropriate stepping routines to actually produce the +run end "edgelist" structures. + +:ol. +:li."Interior" calls StepLine or StepConic or StepBezier as appropriate +to produce run ends. +:li.Occasionally these routines will notice a change in Y direction +and will call ChangeDirection (through the GOING_TO macro); this is +a call back to the REGIONS module. +:li.ChangeDirection will call whatever function is in the region +structure; for Interior, this function is 'newfilledge'. +:li.Newfilledge will call NewEdge to create a new edgelist structure, +then, call SortSwath to sort it onto the linked list being built at +the region "anchor". +:eol. + +By making the function called by ChangeDirection be a parameter of the +region, we allow the same ChangeDirection logic to be used by stroking. +*/ + +/*SHARED LINE(S) ORIGINATED HERE*/ + +struct region *Interior(p, fillrule) + register struct segment *p; /* take interior of this path */ + register int fillrule; /* rule to follow if path crosses itself */ +{ + register fractpel x,y; /* keeps ending point of path segment */ + fractpel lastx,lasty; /* previous x,y from path segment before */ + register struct region *R; /* region I will build */ + register struct segment *nextP; /* next segment of path */ + struct fractpoint hint; /* accumulated hint value */ + char tempflag; /* flag; is path temporary? */ + char Cflag; /* flag; should we apply continuity? */ + + IfTrace2((MustTraceCalls),". INTERIOR(%z, %d)\n", p, (long) fillrule); + + if (p == NULL) + return(NULL); +/* +Establish the 'Cflag' continuity flag based on user's fill rule and +our own 'Continuity' pragmatic (0: never do continuity, 1: do what +user asked, >1: do it regardless). +*/ + if (fillrule > 0) { + Cflag = Continuity > 0; + fillrule -= CONTINUITY; + } + else + Cflag = Continuity > 1; + + ARGCHECK((fillrule != WINDINGRULE && fillrule != EVENODDRULE), + "Interior: bad fill rule", NULL, NULL, (1,p), struct region *); + + if (p->type == TEXTTYPE) +/* if (fillrule != EVENODDRULE) + else */ + return((struct region *)UniquePath(p)); + if (p->type == STROKEPATHTYPE) + if (fillrule == WINDINGRULE) + return((struct region *)DoStroke(p)); + else + p = CoercePath(p); + + R = (struct region *)Allocate(sizeof(struct region), &EmptyRegion, 0); + + ARGCHECK(!ISPATHANCHOR(p), "Interior: bad path", p, R, (0), struct region *); + ARGCHECK((p->type != MOVETYPE), "Interior: path not closed", p, R, (0), struct region *); + + +/* changed definition from !ISPERMANENT to references <= 1 3-26-91 PNM */ + tempflag = (p->references <= 1); /* only first segment in path is so marked */ + if (!ISPERMANENT(p->flag)) p->references -= 1; + + R->newedgefcn = newfilledge; +/* +Believe it or not, "R" is now completely initialized. We are counting +on the copy of template to get other fields the way we want them, +namely +:ol. +:li.anchor = NULL +:li.xmin, ymin, xmax, ymax, to minimum and maximum values respectively. +:eol. +Anchor = NULL is very +important to ChangeDirection. +See :hdref refid=CD.. + +To minimize problems of "wrapping" in our pel arithmetic, we keep an +origin of the region which is the first move. Hopefully, that keeps +numbers within plus or minus 32K pels. +*/ + R->origin.x = 0/*TOFRACTPEL(NEARESTPEL(p->dest.x))*/; + R->origin.y = 0/*TOFRACTPEL(NEARESTPEL(p->dest.y))*/; + lastx = - R->origin.x; + lasty = - R->origin.y; +/* +ChangeDirection initializes other important fields in R, such as +lastdy, edge, edgeYstop, edgexmin, and edgexmax. The first segment +is a MOVETYPE, so it will be called first. +*/ +/* +The hints data structure must be initialized once for each path. +*/ + + if (ProcessHints) + InitHints(); /* initialize hint data structure */ + + while (p != NULL) { + + x = lastx + p->dest.x; + y = lasty + p->dest.y; + + IfTrace2((HintDebug > 0),"Ending point = (%p,%p)\n", x, y); + + nextP = p->link; + +/* +Here we start the hints processing by initializing the hint value to +zero. If ProcessHints is FALSE, the value will remain zero. +Otherwise, hint accumulates the computed hint values. +*/ + + hint.x = hint.y = 0; + +/* +If we are processing hints, and this is a MOVE segment (other than +the first on the path), we need to close (reverse) any open hints. +*/ + + if (ProcessHints) + if ((p->type == MOVETYPE) && (p->last == NULL)) { + CloseHints(&hint); + IfTrace2((HintDebug>0),"Closed point= (%p,%p)\n", + x+hint.x, y+hint.y); + } + +/* +Next we run through all the hint segments (if any) attached to this +segment. If ProcessHints is TRUE, we will accumulate computed hint +values. In either case, nextP will be advanced to the first non-HINT +segment (or NULL), and each hint segment will be freed if necessary. +*/ + + while ((nextP != NULL) && (nextP->type == HINTTYPE)) { + if (ProcessHints) + ProcessHint(nextP, x + hint.x, y + hint.y, &hint); + + { + register struct segment *saveP = nextP; + + nextP = nextP->link; + if (tempflag) + Free(saveP); + } + } + +/* +We now apply the full hint value to the ending point of the path segment. +*/ + + x += hint.x; + y += hint.y; + + IfTrace2((HintDebug>0),"Hinted ending point = (%p,%p)\n", x, y); + + switch(p->type) { + + case LINETYPE: + StepLine(R, lastx, lasty, x, y); + break; + + case CONICTYPE: + { + +/* +For a conic curve, we apply half the hint value to the conic midpoint. +*/ + + } + break; + + case BEZIERTYPE: + { + register struct beziersegment *bp = (struct beziersegment *) p; + +/* +For a Bezier curve, we apply the full hint value to the Bezier C point. +*/ + + StepBezier(R, lastx, lasty, + lastx + bp->B.x, lasty + bp->B.y, + lastx + bp->C.x + hint.x, + lasty + bp->C.y + hint.y, + x, y); + } + break; + + case MOVETYPE: +/* +At this point we have encountered a MOVE segment. This breaks the +path, making it disjoint. +*/ + if (p->last == NULL) /* i.e., not first in path */ + ChangeDirection(CD_LAST, R, lastx, lasty, (fractpel) 0); + + ChangeDirection(CD_FIRST, R, x, y, (fractpel) 0); +/* +We'll just double check for closure here. We forgive an appended +MOVETYPE at the end of the path, if it isn't closed: +*/ + if (!ISCLOSED(p->flag) && p->link != NULL) + return((struct region *)ArgErr("Fill: sub-path not closed", p, NULL)); + break; + + default: + abort("Interior: path type error"); + } +/* +We're done with this segment. Advance to the next path segment in +the list, freeing this one if necessary: +*/ + lastx = x; lasty = y; + + if (tempflag) + Free(p); + p = nextP; + } + ChangeDirection(CD_LAST, R, lastx, lasty, (fractpel) 0); + R->ending.x = lastx; + R->ending.y = lasty; +/* +Finally, clean up the region's based on the user's 'fillrule' request: +*/ + if (Cflag) + ApplyContinuity(R); + if (fillrule == WINDINGRULE) + Unwind(R->anchor); + return(R); +} +/* +:h4.Unwind() - Discards Edges That Fail the Winding Rule Test + +The winding rule says that upward going edges should be paired with +downward going edges only, and vice versa. So, if two upward edges +or two downward edges are nominally left/right pairs, Unwind() should +discard the second one. Everything should balance; we should discard +an even number of edges; of course, we abort if we don't. +*/ +static Unwind(area) + register struct edgelist *area; /* input area modified in place */ +{ + register struct edgelist *last,*next; /* struct before and after current one */ + register int y; /* ymin of current swath */ + register int count,newcount; /* winding count registers */ + + IfTrace1((RegionDebug>0),"...Unwind(%z)\n", area); + + while (VALIDEDGE(area)) { + + count = 0; + y = area->ymin; + + do { + next = area->link; + + if (ISDOWN(area->flag)) + newcount = count + 1; + else + newcount = count - 1; + + if (count == 0 || newcount == 0) + last = area; + else + discard(last, next); + + count = newcount; + area = next; + + } while (area != NULL && area->ymin == y); + + if (count != 0) + abort("Unwind: uneven edges"); + } +} +/* +:h3."workedge" Array + +This is a statically allocated array where edges are built +before being copied into more permanent storage by NewEdge(). +*/ + +#ifndef MAXEDGE +#define MAXEDGE 1000 +#endif + +static pel workedge[MAXEDGE]; +static pel *currentworkarea = workedge; +static pel currentsize = MAXEDGE; + +/* +:h3 id=cd.ChangeDirection() - Called When Y Direction Changes + +The rasterizing routines call this entry point when they detect +a change in Y. We then build the current edge and sort it into +emerging edgelist at 'anchor' by calling whatever "newedgefcn" +is appropriate. +*/ + +void ChangeDirection(type, R, x, y, dy) + int type; /* CD_FIRST, CD_CONTINUE, or CD_LAST */ + register struct region *R; /* region in which we are changing direction */ + fractpel x,y; /* current beginning x,y */ + fractpel dy; /* direction and magnitude of change in y */ +{ + register fractpel ymin,ymax; /* minimum and maximum Y since last call */ + register fractpel x_at_ymin,x_at_ymax; /* their respective X's */ + register pel iy; /* nearest integer pel to 'y' */ + register pel idy; /* nearest integer pel to 'dy' */ + register int ydiff; /* allowed Y difference in 'currentworkarea' */ + + IfTrace4((RegionDebug>0),"Change Y direction (%d) from (%p,%p), dy=%p\n", + (long) type, x, y, dy); + + if (type != CD_FIRST) { + + if (R->lastdy > 0) { + ymin = R->firsty; + x_at_ymin = R->firstx; + ymax = y; + x_at_ymax = x; + } + else { + ymin = y; + x_at_ymin = x; + ymax = R->firsty; + x_at_ymax = R->firstx; + } + + if (ymax < ymin) + abort("negative sized edge?"); + + + (*R->newedgefcn)(R, R->edgexmin, R->edgexmax, ymin, ymax, + R->lastdy > 0, x_at_ymin, x_at_ymax); + + } + + R->firsty = y; + R->firstx = x; + R->lastdy = dy; + + iy = NEARESTPEL(y); + idy = NEARESTPEL(dy); + if (currentworkarea != workedge && idy < MAXEDGE && idy > -MAXEDGE) { + NonObjectFree(currentworkarea); + currentworkarea = workedge; + currentsize = MAXEDGE; + } + ydiff = currentsize - 1; + if (dy > 0) { + R->edge = ¤tworkarea[-iy]; + R->edgeYstop = TOFRACTPEL(ydiff + iy) + FPHALF; + } + else { + R->edge = ¤tworkarea[ydiff - iy]; + R->edgeYstop = TOFRACTPEL(iy - ydiff) - FPHALF; + } + R->edgexmax = R->edgexmin = x; +/* +If this is the end of a subpath, we complete the subpath circular +chain: +*/ + if (type == CD_LAST && R->lastedge != NULL) { + register struct edgelist *e = R->firstedge; + + while (e->subpath != NULL) + e = e->subpath; + e->subpath = R->lastedge; + R->lastedge = R->firstedge = NULL; + } +} +/* +:h3 id=newfill.newfilledge() - Called When We Have a New Edge While Filling + +This is the prototypical "newedge" function passed to "Rasterize" and +stored in "newedgefcn" in the region being built. + +If the edge is non-null, we sort it onto the list of edges we are +building at "anchor". + +This function also has to keep the bounding box of the region +up to date. +*/ + +static void newfilledge(R, xmin, xmax, ymin, ymax, isdown) + register struct region *R; /* region being built */ + fractpel xmin,xmax; /* X range of this edge */ + fractpel ymin,ymax; /* Y range of this edge */ + int isdown; /* flag: TRUE means edge goes down, else up */ +{ + + register pel pelxmin,pelymin,pelxmax,pelymax; /* pel versions of bounds */ + register struct edgelist *edge; /* newly created edge */ + + pelymin = NEARESTPEL(ymin); + pelymax = NEARESTPEL(ymax); + if (pelymin == pelymax) + return; + + pelxmin = NEARESTPEL(xmin); + pelxmax = NEARESTPEL(xmax); + + if (pelxmin < R->xmin) R->xmin = pelxmin; + if (pelxmax > R->xmax) R->xmax = pelxmax; + if (pelymin < R->ymin) R->ymin = pelymin; + if (pelymax > R->ymax) R->ymax = pelymax; + + edge = NewEdge(pelxmin, pelxmax, pelymin, pelymax, &R->edge[pelymin], isdown); + edge->subpath = R->lastedge; + R->lastedge = edge; + if (R->firstedge == NULL) + R->firstedge = edge; + + R->anchor = SortSwath(R->anchor, edge, swathxsort); + +} + +/* +:h2.Sorting Edges + +:h3.SortSwath() - Vertically Sort an Edge into a Region + +This routine sorts an edge or a pair of edges into a growing region, +so that the region maintains its top-to-bottom, left-to-right form. +The rules for sorting horizontally may vary depending on what you +are doing, but the rules for vertical sorting are always the same. +This routine is passed an argument that is a function that will +perform the horizontal sort on demand (for example, swathxsort() or +SwathUnion()). + +This is a recursive routine. A new edge (or edge pair) may overlap +the list I am building in strange and wonderful ways. Edges may +cross. When this happens, my strategy is to split the incoming edge +(or the growing list) in two at that point, execute the actual sort on +the top part of the split, and recursively call myself to figure out +exactly where the bottom part belongs. +*/ + +#define TOP(e) ((e)->ymin) /* the top of an edge (for readability */ +#define BOTTOM(e) ((e)->ymax) /* the bottom of an edge (for readability */ + +struct edgelist *SortSwath(anchor, edge, swathfcn) + struct edgelist *anchor; /* list being built */ + register struct edgelist *edge; /* incoming edge or pair of edges */ + struct edgelist *(*swathfcn)(); /* horizontal sorter */ +{ + register struct edgelist *before,*after; + struct edgelist base; + + if (RegionDebug > 0) { + if (RegionDebug > 2) { + IfTrace3(TRUE,"SortSwath(anchor=%z, edge=%z, fcn=%x)\n", + anchor, edge, swathfcn); + } + else { + IfTrace3(TRUE,"SortSwath(anchor=%x, edge=%x, fcn=%x)\n", + anchor, edge, swathfcn); + } + } + if (anchor == NULL) + return(edge); + + before = &base; + before->ymin = before->ymax = MINPEL; + before->link = after = anchor; + +/* +If the incoming edge is above the current list, we connect the current +list to the bottom of the incoming edge. One slight complication is +if the incoming edge overlaps into the current list. Then, we +first split the incoming edge in two at the point of overlap and recursively +call ourselves to sort the bottom of the split into the current list: +*/ + if (TOP(edge) < TOP(after)) { + if (BOTTOM(edge) > TOP(after)) { + + after = SortSwath(after, splitedge(edge, TOP(after)), swathfcn); + } + vertjoin(edge, after); + return(edge); + } +/* +At this point the top of edge is not higher than the top of the list, +which we keep in 'after'. We move the 'after' point down the list, +until the top of the edge occurs in the swath beginning with 'after'. + +If the bottom of 'after' is below the bottom of the edge, we have to +split the 'after' swath into two parts, at the bottom of the edge. +If the bottom of 'after' is above the bottom of the swath, +*/ + + while (VALIDEDGE(after)) { + + if (TOP(after) == TOP(edge)) { + if (BOTTOM(after) > BOTTOM(edge)) + vertjoin(after, splitedge(after, BOTTOM(edge))); + else if (BOTTOM(after) < BOTTOM(edge)) { + after = SortSwath(after, + splitedge(edge, BOTTOM(after)), swathfcn); + } + break; + } + else if (TOP(after) > TOP(edge)) { + IfTrace0((BOTTOM(edge) < TOP(after) && RegionDebug > 0), + "SortSwath: disjoint edges\n"); + if (BOTTOM(edge) > TOP(after)) { + after = SortSwath(after, + splitedge(edge, TOP(after)), swathfcn); + } + break; + } + else if (BOTTOM(after) > TOP(edge)) + vertjoin(after, splitedge(after, TOP(edge))); + + before = after; + after = after->link; + } + +/* +At this point 'edge' exactly corresponds in height to the current +swath pointed to by 'after'. +*/ + if (after != NULL && TOP(after) == TOP(edge)) { + before = (*swathfcn)(before, edge); + after = before->link; + } +/* +At this point 'after' contains all the edges after 'edge', and 'before' +contains all the edges before. Whew! A simple matter now of adding +'edge' to the linked list in its rightful place: +*/ + before->link = edge; + if (RegionDebug > 1) { + IfTrace3(TRUE,"SortSwath: in between %x and %x are %x", + before, after, edge); + while (edge->link != NULL) { + edge = edge->link; + IfTrace1(TRUE," and %x", edge); + } + IfTrace0(TRUE,"\n"); + } + else + for (; edge->link != NULL; edge = edge->link) { ; } + + edge->link = after; + return(base.link); +} + +/* +:h3.splitedge() - Split an Edge or Swath in Two at a Given Y Value + +This function returns the edge or swath beginning at the Y value, and +is guaranteed not to change the address of the old swath while splitting +it. +*/ + +static struct edgelist *splitedge(list, y) + struct edgelist *list; /* area to split */ + register pel y; /* Y value to split list at */ +{ + register struct edgelist *new; /* anchor for newly built list */ + register struct edgelist *last; /* end of newly built list */ + register struct edgelist *r; /* temp pointer to new structure */ + register struct edgelist *lastlist; /* temp pointer to last 'list' value */ + + IfTrace2((RegionDebug > 1),"splitedge of %x at %d ", list, (long) y); + + lastlist = new = NULL; + + while (list != NULL) { + if (y < list->ymin) + break; + if (y >= list->ymax) + abort("splitedge: above top of list"); + if (y == list->ymin) + abort("splitedge: would be null"); + + r = (struct edgelist *)Allocate(sizeof(struct edgelist), list, 0); +/* +At this point 'r' points to a copy of the single structure at 'list'. +We will make 'r' be the new split 'edgelist'--the lower half. +We don't bother to correct 'xmin' and 'xmax', we'll take the +the pessimistic answer that results from using the old values. +*/ + r->ymin = y; + r->xvalues = list->xvalues + (y - list->ymin); +/* +Note that we do not need to allocate new memory for the X values, +they can remain with the old "edgelist" structure. We do have to +update that old structure so it is not as high: +*/ + list->ymax = y; +/* +Insert 'r' in the subpath chain: +*/ + r->subpath = list->subpath; + list->subpath = r; +/* +Now attach 'r' to the list we are building at 'new', and advance +'list' to point to the next element in the old list: +*/ + if (new == NULL) + new = r; + else + last->link = r; + last = r; + lastlist = list; + list = list->link; + } +/* +At this point we have a new list built at 'new'. We break the old +list at 'lastlist', and add the broken off part to the end of 'new'. +Then, we return the caller a pointer to 'new': +*/ + if (new == NULL) + abort("null splitedge"); + lastlist->link = NULL; + last->link = list; + IfTrace1((RegionDebug > 1),"yields %x\n", new); + return(new); +} + +/* +:h3.vertjoin() - Join Two Disjoint Edge Lists Vertically + +The two edges must be disjoint vertically. +*/ +static void vertjoin(top, bottom) + register struct edgelist *top; /* uppermost region */ + register struct edgelist *bottom; /* bottommost region */ +{ + if (BOTTOM(top) > TOP(bottom)) + abort("vertjoin not disjoint"); + + for (; top->link != NULL; top=top->link) { ; } + + top->link = bottom; + return; +} + +/* +:h3.swathxsort() - Sorting by X Values + +We need to sort 'edge' into its rightful +place in the swath by X value, taking care that we do not accidentally +advance to the next swath while searching for the correct X value. Like +all swath functions, this function returns a pointer to the edge +BEFORE the given edge in the sort. +*/ + +static struct edgelist *swathxsort(before0, edge) + register struct edgelist *before0; /* edge before this swath */ + register struct edgelist *edge; /* input edge */ +{ + register struct edgelist *before; + register struct edgelist *after; + register pel y; + + before = before0; + after = before->link; + + while (after != NULL && TOP(after) == TOP(edge)) { + + register pel *x1,*x2; + + y = TOP(edge); + x1 = after->xvalues; + x2 = edge->xvalues; + + while (y < BOTTOM(edge) && *x1 == *x2) { + x1++; x2++; y++; + } + if (y >= BOTTOM(edge)) { + edge->flag |= ISAMBIGUOUS(ON); + after->flag |= ISAMBIGUOUS(ON); + break; + } + + if (*x1 >= *x2) + break; + + before = after; + after = after->link; + } + +/* +At this point, 'edge' is between 'before' and 'after'. If 'edge' didn't +cross either of those other edges, we would be done. We check for +crossing. If it does cross, we split the problem up by calling SortSwath +recursively with the part of the edge that is below the crossing point: +*/ +{ + register int h0,h; /* height of edge--number of scans */ + + h0 = h = BOTTOM(edge) - y; + y -= TOP(edge); + + if (h0 <= 0) { + IfTrace0((RegionDebug>0),"swathxsort: exactly equal edges\n"); + return(before); + } + + if (TOP(before) == TOP(edge)) + h -= crosses(h, &before->xvalues[y], &edge->xvalues[y]); + if (after != NULL && TOP(after) == TOP(edge)) + h -= crosses(h, &edge->xvalues[y], &after->xvalues[y]); + + if (h < h0) { + SortSwath(before0->link, + splitedge(edge, TOP(edge) + y + h), + swathxsort); + + } +} + + return(before); +} +/* +:h3.SwathUnion() - Union Two Edges by X Value + +We have a left and right edge that must be unioned into a growing +swath. If they are totally disjoint, they are just added in. The +fun comes in they overlap the existing edges. Then some edges +will disappear. +*/ + +struct edgelist *SwathUnion(before0, edge) + register struct edgelist *before0; /* edge before the swath */ + register struct edgelist *edge; /* list of two edges to be unioned */ +{ + register int h; /* saves height of edge */ + register struct edgelist *rightedge; /* saves right edge of 'edge' */ + register struct edgelist *before,*after; /* edge before and after */ + int h0; /* saves initial height */ + + IfTrace2((RegionDebug > 1),"SwathUnion entered, before=%x, edge=%x\n", + before0, edge); + + h0 = h = edge->ymax - edge->ymin; + if (h <= 0) + abort("SwathUnion: 0 height swath?"); + + before = before0; + after = before->link; + + while (after != NULL && TOP(after) == TOP(edge)) { + register struct edgelist *right; + + right = after->link; + if (right->xvalues[0] >= edge->xvalues[0]) + break; + before = right; + after = before->link; + } +/* +This is the picture at this point. 'L' indicates a left hand edge, +'R' indicates the right hand edge. +'<--->' indicates the degree of uncertainty as to its placement +relative to other edges: +:xmp atomic. + before after + R <---L----> R L R L R + <---L---> <------R--------------------------> + edge +:exmp. +In case the left of 'edge' touches 'before', we need to reduce +the height by that amount. +*/ + if (TOP(before) == TOP(edge)) + h -= touches(h, before->xvalues, edge->xvalues); + + rightedge = edge->link; + + if (after == NULL || TOP(after) != TOP(edge) || + after->xvalues[0] > rightedge->xvalues[0]) { + IfTrace2((RegionDebug > 1), + "SwathUnion starts disjoint: before=%x after=%x\n", + before, after); +/* +On this side of the the above 'if', the new edge is disjoint from the +existing edges in the swath. This is the picture: +:xmp atomic. + before after + R L R L R L R + L R + edge +:exmp. +We will verify it remains disjoint for the entire height. If the +situation changes somewhere down the edge, we split the edge at that +point and recursively call ourselves (through 'SortSwath') to figure +out the new situation: +*/ + if (after != NULL && TOP(after) == TOP(edge)) + h -= touches(h, rightedge->xvalues, after->xvalues); + if (h < h0) + SortSwath(before0->link, splitedge(edge, edge->ymin + h), t1_SwathUnion); + /* go to "return" this edge pair; it is totally disjoint */ + } + else { +/* +At this point, at the 'else', we know that the +new edge overlaps one or more pairs in the existing swath. Here is +a picture of our knowledge and uncertainties: +:xmp atomic. + before after + R L R L R L R + <---L---> <---R-------------------> + edge +:exmp. +We need to move 'after' along until it is to the right of the +right of 'edge'. ('After' should always point to a left edge of a pair:) +*/ + register struct edgelist *left; /* variable to keep left edge in */ + + do { + left = after; + after = (after->link)->link; + + } while (after != NULL && TOP(after) == TOP(edge) + && after->xvalues[0] <= rightedge->xvalues[0]); +/* +At this point this is the picture: +:xmp atomic. + before left after + R L R L R L R + <---L---> <---R---> + edge +:exmp. +We need to verify that the situation stays like this all the way +down the edge. Again, if the +situation changes somewhere down the edge, we split the edge at that +point and recursively call ourselves (through 'SortSwath') to figure +out the new situation: +*/ + + h -= crosses(h, left->xvalues, rightedge->xvalues); + h -= crosses(h, edge->xvalues, ((before->link)->link)->xvalues); + + if (after != NULL && TOP(after) == TOP(edge)) + + h -= touches(h, rightedge->xvalues, after->xvalues); + + IfTrace3((RegionDebug > 1), + "SwathUnion is overlapped until %d: before=%x after=%x\n", + (long) TOP(edge) + h, before, after); +/* +OK, if we touched either of our neighbors we need to split at that point +and recursively sort the split edge onto the list. One tricky part +is that when we recursively sort, 'after' will change if it was not +in our current swath: +*/ + if (h < h0) { + SortSwath(before0->link, + splitedge(edge, edge->ymin + h), + t1_SwathUnion); + + if (after == NULL || TOP(after) != TOP(edge)) + for (after = before0->link; + TOP(after) == TOP(edge); + after = after->link) { ; } + } +/* +Now we need to augment 'edge' by the left and right of the overlapped +swath, and to discard all edges between before and after, because they +were overlapped and have been combined with the new incoming 'edge': +*/ + edge->xmin = MIN(edge->xmin, (before->link)->xmin); + edge->xmax = MIN(edge->xmax, (before->link)->xmax); + edgemin(h, edge->xvalues, (before->link)->xvalues); + rightedge->xmin = MAX(rightedge->xmin, (left->link)->xmin); + rightedge->xmax = MAX(rightedge->xmax, (left->link)->xmax); + edgemax(h, rightedge->xvalues, (left->link)->xvalues); + discard(before, after); + } + return(before); +} +/* +:h3.swathrightmost() - Simply Sorts New Edge to Rightmost of Swath + +Like all swath functions, this function returns a pointer to the edge +BEFORE the given edge in the sort. +*/ + +static struct edgelist *swathrightmost(before, edge) + register struct edgelist *before; /* edge before this swath */ + register struct edgelist *edge; /* input edge */ +{ + register struct edgelist *after; + + after = before->link; + + while (after != NULL && TOP(after) == TOP(edge)) { + before = after; + after = after->link; + } + + return(before); + +} +/* +:h3.touches() - Returns the Remaining Height When Two Edges Touch + +So, it will return 0 if they never touch. Allows incredibly(?) mnemonic +if (touches(...)) construct. +*/ + +static int touches(h, left, right) + register int h; + register pel *left,*right; +{ + for (; h > 0; h--) + if (*left++ >= *right++) + break; + return(h); +} +/* +:h3.crosses() - Returns the Remaining Height When Two Edges Cross + +So, it will return 0 if they never cross. +*/ + +static int crosses(h, left, right) + register int h; + register pel *left,*right; +{ + for (; h > 0; h--) + if (*left++ > *right++) + break; + return(h); +} +/* +:h3.cedgemin() - Stores the Mininum of an Edge and an X Value +*/ + +static void cedgemin(h, e1, x) + register int h; + register pel *e1; + register pel x; +{ + for (; --h >= 0; e1++) + if (*e1 > x) + *e1 = x; +} +/* +:h3.cedgemax() - Stores the Maximum of an Edge and an X Value +*/ + +static void cedgemax(h, e1, x) + register int h; + register pel *e1; + register pel x; +{ + for (; --h >= 0; e1++) + if (*e1 < x) + *e1 = x; +} +/* +:h3.edgemin() - Stores the Mininum of Two Edges in First Edge +*/ + +static void edgemin(h, e1, e2) + register int h; + register pel *e1,*e2; +{ + for (; --h >= 0; e1++,e2++) + if (*e1 > *e2) + *e1 = *e2; +} +/* +:h3.edgemax() - Stores the Maximum of Two Edges in First Edge +*/ + +static void edgemax(h, e1, e2) + register int h; + register pel *e1,*e2; +{ + for (; --h >= 0; e1++,e2++) + if (*e1 < *e2) + *e1 = *e2; +} +/* +:h3 id=discard.discard() - Discard All Edges Between Two Edges + +At first glance it would seem that we could discard an edgelist +structure merely by unlinking it from the list and freeing it. You are +wrong, region-breath! For performance, the X values associated with an +edge are allocated contiguously with it. So, we free the X values when +we free a structure. However, once an edge has been split, we are no +longer sure which control block actually is part of the memory block +that contains the edges. Rather than trying to decide, we play it safe +and never free part of a region. + +So, to mark a 'edgelist' structure as discarded, we move it to the end +of the list and set ymin=ymax. +*/ + +static discard(left, right) + register struct edgelist *left,*right; /* all edges between here exclusive */ + /* should be discarded */ +{ + register struct edgelist *beg,*end,*p; + + IfTrace2((RegionDebug > 0),"discard: l=%x, r=%x\n", left, right); + + beg = left->link; + if (beg == right) + return; + + for (p = beg; p != right; p = p->link) { + if (p->link == NULL && right != NULL) + abort("discard(): ran off end"); + IfTrace1((RegionDebug > 0),"discarding %x\n", p); + p->ymin = p->ymax = 32767; + end = p; + } + /* + * now put the chain beg/end at the end of right, if it is not + * already there: + */ + if (right != NULL) { + left->link = right; + while (right->link != NULL) + right = right->link; + right->link = beg; + } + end->link = NULL; +} + +/* +:h2.Changing the Representation of Regions + +For convenience and/or performance, we sometimes like to change the way +regions are represented. This does not change the object itself, just +the representation, so these transformations can be made on a permanent +region. + +*/ + +void MoveEdges(R, dx, dy) + register struct region *R; /* region to modify */ + register fractpel dx,dy; /* delta X and Y to move edge list by */ +{ + register struct edgelist *edge; /* for looping through edges */ + + R->origin.x += dx; + R->origin.y += dy; + R->ending.x += dx; + R->ending.y += dy; + if (R->thresholded != NULL) { + R->thresholded->origin.x -= dx; + R->thresholded->origin.y -= dy; + } +/* +From now on we will deal with dx and dy as integer pel values: +*/ + dx = NEARESTPEL(dx); + dy = NEARESTPEL(dy); + if (dx == 0 && dy == 0) + return; + + R->xmin += dx; + R->xmax += dx; + R->ymin += dy; + R->ymax += dy; + + for (edge = R->anchor; VALIDEDGE(edge); edge = edge->link) { + edge->ymin += dy; + edge->ymax += dy; + if (dx != 0) { + register int h; /* loop index; height of edge */ + register pel *Xp; /* loop pointer to X values */ + + edge->xmin += dx; + edge->xmax += dx; + for (Xp = edge->xvalues, h = edge->ymax - edge->ymin; + --h >= 0; ) + *Xp++ += dx; + } + } +} + +/* +:h3.UnJumble() - Sort a Region Top to Bottom + +It is an open question whether it pays in general to do this. +*/ + +void UnJumble(region) + struct region *region; /* region to sort */ +{ + register struct edgelist *anchor; /* new lists built here */ + register struct edgelist *edge; /* edge pointer for loop */ + register struct edgelist *next; /* ditto */ + + anchor = NULL; + + for (edge=region->anchor; VALIDEDGE(edge); edge=next) { + if (edge->link == NULL) + abort("UnJumble: unpaired edge?"); + next = edge->link->link; + edge->link->link = NULL; + anchor = SortSwath(anchor, edge, t1_SwathUnion); + } + + if (edge != NULL) + vertjoin(anchor, edge); + + region->anchor = anchor; + region->flag &= ~ISJUMBLED(ON); +} + +/* +*/ + +static OptimizeRegion(R) + struct region *R; /* region to optimize */ +{ + register pel *xP; /* pel pointer for inner loop */ + register int x; /* holds X value */ + register int xmin,xmax; /* holds X range */ + register int h; /* loop counter */ + register struct edgelist *e; /* edgelist pointer for loop */ + + R->flag |= ISRECTANGULAR(ON); + + for (e = R->anchor; VALIDEDGE(e); e=e->link) { + xmin = MAXPEL; + xmax = MINPEL; + for (h = e->ymax - e->ymin, xP = e->xvalues; --h >= 0;) { + x = *xP++; + if (x < xmin) xmin = x; + if (x > xmax) xmax = x; + } + if (xmin != xmax || (xmin != R->xmin && xmax != R->xmax)) + R->flag &= ~ISRECTANGULAR(ON); + if (xmin < e->xmin || xmax > e->xmax) + abort("Tighten: existing edge bound was bad"); + if (xmin < R->xmin || xmax > R->xmax) + abort("Tighten: existing region bound was bad"); + e->xmin = xmin; + e->xmax = xmax; + } + R->flag |= ISOPTIMIZED(ON); +} + +/* +:h2.Miscelaneous Routines + +:h3.MoreWorkArea() - Allocate New Space for "edge" + +Our strategy is to temporarily allocate an array to hold this +unexpectedly large edge. ChangeDirection frees this array any time +it gets a shorter 'dy'. +*/ + +/*ARGSUSED*/ +void MoreWorkArea(R, x1, y1, x2, y2) + struct region *R; /* region we are generating */ + fractpel x1,y1; /* starting point of line */ + fractpel x2,y2; /* ending point of line */ +{ + register int idy; /* integer dy of line */ + + idy = NEARESTPEL(y1) - NEARESTPEL(y2); + if (idy < 0) idy = - idy; + + /* + * we must add one to the delta for the number of run ends we + * need to store: + */ + if (++idy > currentsize) { + IfTrace1((RegionDebug > 0),"Allocating edge of %d pels\n", idy); + if (currentworkarea != workedge) + NonObjectFree(currentworkarea); + currentworkarea = (pel *)Allocate(0, NULL, idy * sizeof(pel)); + currentsize = idy; + } + ChangeDirection(CD_CONTINUE, R, x1, y1, y2 - y1); +} + +/* +:h3.BoxClip() - Clip a Region to a Rectangle + +BoxClip also duplicates the region if it is permanent. Note the +clipping box is specified in REGION coordinates, that is, in +coordinates relative to the region (0,0) point +*/ + +struct region *BoxClip(R, xmin, ymin, xmax, ymax) + register struct region *R; /* region to clip */ + register pel xmin,ymin; /* upper left hand corner of rectangle */ + register pel xmax,ymax; /* lower right hand corner */ +{ + struct edgelist anchor; /* pretend edgelist to facilitate discards */ + register struct edgelist *e,*laste; + + IfTrace1((OffPageDebug),"BoxClip of %z:\n", R); + + R = UniqueRegion(R); + + if (xmin > R->xmin) { + IfTrace2((OffPageDebug),"BoxClip: left clip old %d new %d\n", + (long) R->xmin, (long) xmin); + R->xmin = xmin; + } + if (xmax < R->xmax) { + IfTrace2((OffPageDebug),"BoxClip: right clip old %d new %d\n", + (long) R->xmax, (long) xmax); + R->xmax = xmax; + } + + if (ymin > R->ymin) { + IfTrace2((OffPageDebug),"BoxClip: top clip old %d new %d\n", + (long) R->ymin, (long) ymin); + R->ymin = ymin; + } + if (ymax < R->ymax) { + IfTrace2((OffPageDebug),"BoxClip: bottom clip old %d new %d\n", + (long) R->ymax, (long) ymax); + R->ymax = ymax; + } + + + laste = &anchor; + anchor.link = R->anchor; + + for (e = R->anchor; VALIDEDGE(e); e = e->link) { + if (TOP(e) < ymin) { + e->xvalues += ymin - e->ymin; + e->ymin = ymin; + } + if (BOTTOM(e) > ymax) + e->ymax = ymax; + if (TOP(e) >= BOTTOM(e)) { + discard(laste, e->link->link); + e = laste; + continue; + } + if (e->xmin < xmin) { + cedgemax(BOTTOM(e) - TOP(e), e->xvalues, xmin); + e->xmin = xmin; + e->xmax = MAX(e->xmax, xmin); + } + if (e->xmax > xmax) { + cedgemin(BOTTOM(e) - TOP(e), e->xvalues, xmax); + e->xmin = MIN(e->xmin, xmax); + e->xmax = xmax; + } + laste = e; + } + + R->anchor = anchor.link; + + return(R); +} + +#ifdef notdef +/* +:h3.CoerceRegion() - Force a TextPath Structure to Become a Region + +We also save the newly created region in the textpath structure, if the +structure was permanent. Then we don't have to do this again. Why not +save it all the time? Well, we certainly could, but I suspect it +wouldn't pay. We would have to make this region permanent (because we +couldn't have it be consumed) and this would probably require +unnecessary CopyRegions in most cases. +*/ + +struct region *CoerceRegion(tp) + register struct textpath *tp; /* input TEXTTYPE */ +{ + struct segment *path; /* temporary character path */ + struct region *R; /* returned region */ + + + R = Interior(path, EVENODDRULE); + return(R); +} +#endif + +/* +:h3.RegionBounds() - Returns Bounding Box of a Region +*/ + +struct segment *RegionBounds(R) + register struct region *R; +{ + extern struct XYspace *IDENTITY; + + register struct segment *path; /* returned path */ + + path = BoxPath(IDENTITY, R->ymax - R->ymin, R->xmax - R->xmin); + path = Join(PathSegment(MOVETYPE, R->origin.x + TOFRACTPEL(R->xmin), + R->origin.y + TOFRACTPEL(R->ymin) ), + path); + return(path); +} + +/* +:h2.Formatting/Dump Routines for Debug + +:h3.DumpArea() - Display a Region +*/ +void DumpArea(area) + register struct region *area; +{ + IfTrace1(TRUE,"Dumping area %x,", area); + IfTrace4(TRUE," X %d:%d Y %d:%d;", (long) area->xmin, + (long) area->xmax, (long) area->ymin,(long) area->ymax); + IfTrace4(TRUE," origin=(%p,%p), ending=(%p,%p)\n", + area->origin.x, area->origin.y, area->ending.x, area->ending.y); + DumpEdges(area->anchor); +} + +#define INSWATH(p, y0, y1) (p != NULL && p->ymin == y0 && p->ymax == y1) +/* +:h3.DumpEdges() - Display Run End Lists (Edge Lists) +*/ + +static pel RegionDebugYMin = MINPEL; +static pel RegionDebugYMax = MAXPEL; + +void DumpEdges(edges) + register struct edgelist *edges; +{ + register struct edgelist *p,*p2; + register pel ymin = MINPEL; + register pel ymax = MINPEL; + register int y; + + if (edges == NULL) { + IfTrace0(TRUE," NULL area.\n"); + return; + } + if (RegionDebug <= 1) { + for (p=edges; p != NULL; p = p->link) { + edgecheck(p, ymin, ymax); + ymin = p->ymin; ymax = p->ymax; + IfTrace3(TRUE,". at %x type=%d flag=%x", + p, (long) p->type,(long) p->flag); + IfTrace4(TRUE," bounding box HxW is %dx%d at (%d,%d)\n", + (long) ymax - ymin, (long) p->xmax - p->xmin, + (long) p->xmin, (long) ymin); + } + } + else { + + for (p2=edges; p2 != NULL; ) { + + edgecheck(p2, ymin, ymax); + ymin = p2->ymin; + ymax = p2->ymax; + + if (RegionDebug > 3 || (ymax > RegionDebugYMin + && ymin < RegionDebugYMax)) { + IfTrace2 (TRUE,". Swath from %d to %d:\n", + ymin, ymax); + for (p=p2; INSWATH(p,ymin,ymax); p = p->link) { + IfTrace4(TRUE,". . at %x[%x] range %d:%d, ", + p, (long) p->flag, + (long) p->xmin, (long)p->xmax); + IfTrace1(TRUE, "subpath=%x,\n", p->subpath); + } + } + for (y=MAX(ymin,RegionDebugYMin); y < MIN(ymax, RegionDebugYMax); y++) { + IfTrace1(TRUE,". . . Y[%5d] ", (long) y); + for (p=p2; INSWATH(p,ymin,ymax); p = p->link) + IfTrace1(TRUE,"%5d ", + (long) p->xvalues[y - ymin]); + IfTrace0(TRUE,"\n"); + } + while (INSWATH(p2, ymin, ymax)) + p2 = p2->link; + } + } +} + +/* +:h3.edgecheck() - For Debug, Verify that an Edge Obeys the Rules +*/ + +/*ARGSUSED*/ +static edgecheck(edge, oldmin, oldmax) + struct edgelist *edge; + int oldmin,oldmax; +{ + if (edge->type != EDGETYPE) + abort("EDGE ERROR: non EDGETYPE in list"); +/* +The following check is not valid if the region is jumbled so I took it +out: +*/ +/* if (edge->ymin < oldmax && edge->ymin != oldmin) + abort("EDGE ERROR: overlapping swaths"); */ +}