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

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

/*-
	General utilities for dealing with shapes

	shape.c, Thu Oct 17 10:38:47 1985

 */

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

struct shape InfiniteShape = {
    0, 0,
    0x7fff, 0x7fff,
    STATIC_OBJ,
    1,
};

struct shape InvalidShape = {
    0, 0,
    0, 0,
    STATIC_OBJ,
    1,
};

/* Free the trapezons associated with a shape */
sh_freeshape(sh)
    register struct shape *sh;
{
    if (!sh->is_rect) {
	register struct shape_trapezon *p, *next;
	next = sh->trapset;
	while (p = next) {
	    if (--p->refcnt > 0)
		break;
	    next = p->next;
	    QFREE(p);
	}
	sh->trapset = 0;
    }
    if (sh->refcnt == STATIC_OBJ - 1)
	sh_incref(sh);
    else {
	assert(sh->refcnt == 0);
	qtfree(sh);
    }
}

/* Copy a set of trapezons */
struct shape *
sh_copy(sh)
    register struct shape *sh;
{
    register struct shape_trapezon *ret, *tail;
    register struct shape_trapezon *t = sh->trapset;
    register struct shape *p;
    ret = 0;
    if (!sh->is_rect)
	while (t) {
	    register    size;
	    register struct shape_trapezon *new;
	    size = sizeof(struct shape_trapezon)
		+ sizeof(struct shape_trapseg) * t->used;
	    QALLOC(new, size, (struct shape_trapezon *));
	    bcopy(t, new, size);
	    new->size = new->used;
	    new->next = 0;
	    new->refcnt = 1;
	    if (ret)
		tail->next = new;
	    else
		ret = new;
	    tail = new;
	    t = t->next;
	}
    qtalloc(p, (struct shape *));
    *p = *sh;
    p->refcnt = 1;
    p->trapset = ret;
    sh_decref(sh);
    return p;
}

/*
 * Translate a shape by (dx,dy).  Believe it or not, this apparently brute
 * force technique really does win over passing offsets around.  Think
 * about counting the number of additions, and about how often the offsets
 * would be 0 
 */
struct shape *
sh_translate(sh, dx, dy)
    register struct shape *sh;
    register short dx, dy;
{
    if (sh == 0 || dx == 0 && dy == 0)
	return sh;
    if (sh->refcnt>1 || (!sh->is_rect && sh->trapset->refcnt>1)) sh = sh_copy(sh);
    sh->pos.x += dx;
    sh->pos.y += dy;
    if (!sh->is_rect) {
	register struct shape_trapezon *t;
	for (t = sh->trapset; t; t = t->next) {
	    register struct shape_trapseg *p;
	    t->top += dy;
	    t->bottom += dy;
	    t->left += dx;
	    t->right += dx;
	    for (p = &t->segs[t->used]; p >= &t->segs[0]; --p) {
		p->y += dy;
		p->x1 += dx;
		p->x2 += dx;
	    }
	}
    }
    return sh;
}