1 |
/* Copyright (c) 1986 Regents of the University of California */ |
2 |
|
3 |
/* SCCSid "$SunId$ LBL" */ |
4 |
|
5 |
/* |
6 |
* octree.h - header file for routines using octrees. |
7 |
* |
8 |
* 7/28/85 |
9 |
*/ |
10 |
|
11 |
/* |
12 |
* An octree is expressed as an integer which is either |
13 |
* an index to eight other nodes, the empty tree, or an index |
14 |
* to a set of objects. If the octree has a value: |
15 |
* |
16 |
* > -1: it is an index to eight other nodes. |
17 |
* |
18 |
* -1: it is empty |
19 |
* |
20 |
* < -1: it is an index to a set of objects |
21 |
*/ |
22 |
|
23 |
typedef int OCTREE; |
24 |
|
25 |
#define EMPTY (-1) |
26 |
|
27 |
#define isempty(ot) ((ot) == EMPTY) |
28 |
#define isfull(ot) ((ot) < EMPTY) |
29 |
#define istree(ot) ((ot) > EMPTY) |
30 |
|
31 |
#define oseti(ot) (-(ot)-2) /* object set index */ |
32 |
#define octbi(ot) ((ot)>>8) /* octree block index */ |
33 |
#define octti(ot) (((ot)&0377)<<3)/* octree index in block */ |
34 |
|
35 |
#define MAXOBLK 4095 /* maximum octree block */ |
36 |
|
37 |
extern OCTREE *octblock[MAXOBLK]; /* octree blocks */ |
38 |
|
39 |
#define octkid(ot,br) (octblock[octbi(ot)][octti(ot)+br]) |
40 |
|
41 |
extern OCTREE octalloc(), combine(), fullnode(); |
42 |
|
43 |
/* |
44 |
* The cube structure is used to hold an octree and its cubic |
45 |
* boundaries. |
46 |
*/ |
47 |
|
48 |
typedef struct { |
49 |
OCTREE cutree; /* the octree for this cube */ |
50 |
FVECT cuorg; /* the cube origin */ |
51 |
double cusize; /* the cube size */ |
52 |
} CUBE; |
53 |
|
54 |
extern CUBE thescene; /* the main scene */ |
55 |
|
56 |
/* flags for reading and writing octrees */ |
57 |
#define IO_CHECK 0 /* verify file type */ |
58 |
#define IO_INFO 01 /* information header */ |
59 |
#define IO_SCENE 02 /* objects */ |
60 |
#define IO_TREE 04 /* octree */ |
61 |
#define IO_FILES 010 /* object file names */ |
62 |
#define IO_BOUNDS 020 /* octree boundary */ |
63 |
#define IO_ALL (~0) /* everything */ |
64 |
/* magic number for octree files */ |
65 |
#define OCTMAGIC (275+sizeof(OBJECT)) |
66 |
/* octree node types */ |
67 |
#define OT_EMPTY 0 |
68 |
#define OT_FULL 1 |
69 |
#define OT_TREE 2 |
70 |
/* return values for surface functions */ |
71 |
#define O_MISS 0 /* no intersection */ |
72 |
#define O_HIT 1 /* intersection */ |
73 |
#define O_IN 2 /* cube contained entirely */ |