#ifndef lint
static char sccsid[] = "@(#)pathtoarc.c 9.2 88/01/19 Copyright 1985 Sun Micro";
#endif

/*
 * Copyright (c) 1985 by Sun Microsystems, Inc.
 */

/*-
	Convert a PostScript style path to an arclist

	pathtoarc.c, Thu Sep 19 15:45:44 1985

 */

#ifdef REF
#include <sys/types.h>
#include <ref/config.h>
#endif
#include "shape.h"
#include "qalloc.h"

struct shape_arc *
path_to_arc(path, closed)
    register struct path *path;
{
    register struct path_element *p = path->element + path->startpos;
    register struct shape_arc *ret = 0, *tail, *pathstart = 0, *new;
    register    n = path->used - path->startpos;
    register    laststate = MOVE_TO_FLAG;
    while (--n >= 0) {
	switch (p->variation) {
	case MOVE_TO_FLAG:
	    switch (laststate) {
	    case MOVE_TO_FLAG:
		if (ret == 0) {
		    qtalloc(ret, (struct shape_arc *));
		    tail = ret;
		}
		break;
	    default:
		if (closed)
		    tail->C = pathstart->A;
		else {
		    tail->C = tail->B;
		    tail->sh = 0;
		}
		qtalloc(new, (struct shape_arc *));
		tail->next = new;
		tail = new;
		break;
	    case 0:
		if (closed) {
		    qtalloc(new, (struct shape_arc *));
		    tail->next = new;
		    new->A = tail->C;
		    new->C = pathstart->A;
		    new->B = new->C;
		    new->sh = 0;
		    tail = new;
		}
	    case CLOSEPATH_FLAG:
		qtalloc(new, (struct shape_arc *));
		tail->next = new;
		tail = new;
		break;
	    }
	    tail->A = p->pos;
	    pathstart = tail;
	    break;
	case CLOSEPATH_FLAG:
	    switch (laststate) {
	    case MOVE_TO_FLAG:
	    case CLOSEPATH_FLAG:
		break;
	    case 0:
		qtalloc(new, (struct shape_arc *));
		tail->next = new;
		new->A = tail->C;
		new->B = new->A;
		tail = new;
		tail->sh = 0;
	    default:
		tail->C = pathstart->A;
		break;
	    }
	    pathstart = 0;
	    break;
	case 0:
	    switch (laststate) {
	    case MOVE_TO_FLAG:
		if (ret) {
		    tail->sh = 0;
		    tail->C = p->pos;
		    tail->B = tail->C;
		    break;
		}
	    case CLOSEPATH_FLAG:
		qtalloc(new, (struct shape_arc *));
		if (ret)
		    tail->next = new;
		else
		    ret = new;
		new->A = p->pos;
		tail = new;
		p->variation = MOVE_TO_FLAG;
		pathstart = new;
		break;
	    case 0:
		qtalloc(new, (struct shape_arc *));
		tail->next = new;
		new->A = tail->C;
		tail = new;
		tail->sh = 0;
		tail->C = p->pos;
		tail->B = tail->C;
		break;
	    default:
		tail->C = p->pos;
		break;
	    }
	    break;
	default:
	    switch (laststate) {
	    case MOVE_TO_FLAG:
		if (ret) {
		    tail->B = p->pos;
		    tail->sh = p->variation;
		    break;
		}
	    case CLOSEPATH_FLAG:
		qtalloc(new, (struct shape_arc *));
		if (ret)
		    tail->next = new;
		else
		    ret = new;
		new->A = p->pos;
		tail = new;
		p->variation = MOVE_TO_FLAG;
		pathstart = new;
		break;
	    case 0:
		qtalloc(new, (struct shape_arc *));
		tail->next = new;
		new->A = tail->C;
		tail = new;
		tail->B = p->pos;
		tail->sh = p->variation;
		break;
	    default:
		qtalloc(new, (struct shape_arc *));
		tail->next = new;
		tail->C.x = (tail->B.x + p->pos.x) >> 1;
		tail->C.y = (tail->B.y + p->pos.y) >> 1;
		new->A = tail->C;
		tail = new;
		tail->B = p->pos;
		tail->sh = p->variation;
		break;
	    }
	    break;
	}
	laststate = p->variation;
	p++;
    }
    switch (laststate) {
    case CLOSEPATH_FLAG:
	break;
    case MOVE_TO_FLAG:
	if (ret) {
	    tail->C = tail->A;
	    tail->B = tail->A;
	    tail->sh = 0;
	}
	break;
    case 0:
	if (closed) {
	    qtalloc(new, (struct shape_arc *));
	    tail->next = new;
	    new->A = tail->C;
	    new->B = new->A;
	    new->C = pathstart->A;
	    tail = new;
	    tail->sh = 0;
	}
	break;
    default:
	if (closed)
	    tail->C = pathstart->A;
	else {
	    tail->C = tail->B;
	    tail->sh = 0;
	}
	break;
    }
    if (ret)
	tail->next = ret;
    return ret;
}

freearc(l)
    register struct shape_arc *l;
{
    register struct shape_arc *p, *n;
    p = l;
    do {
	n = p->next;
	qtfree(p);
	p = n;
    } while (p != l);
}