src/hd/sm_stree.h

/* Copyright (c) 1998 Silicon Graphics, Inc. */

/* SCCSid "$SunId$ SGI" */

/*
 *  sm_stree.h - header file for spherical quadtree code:
 *             
 */

#define STR_INDEX(s)  (stRoot_indices[(s)])
#define STR_NTH_INDEX(s,n)  (stRoot_indices[(s)][(n)])

#define ST_NUM_ROOT_NODES 8


/* The base is an octahedron: Each face contains a planar quadtree. At
 the root level, the "top" (positive y) four faces, and bottom four faces
 are stored together:forming two root quadtree nodes
 */

typedef struct _STREE {
  QUADTREE   qt[2];  /* root[0]= top four faces, root[1]=bottom 4 faces*/

}STREE;


#define ST_BASEI(n)            ((n)>>2)     /* root index: top or bottom */
#define ST_INDEX(n)            ((n) & 0x3) /* which child in root */
#define ST_QT(s,i)           ((s)->qt[ST_BASEI(i)]) /* top or bottom root*/
#define ST_QT_PTR(s,i)       (&ST_QT(s,i)) /* ptr to top(0)/bottom(1)root*/
#define ST_TOP_QT(s)         ((s)->qt[0])  /* top root (y>0)*/
#define ST_BOTTOM_QT(s)      ((s)->qt[1])  /* bottom qt (y <= 0)*/
#define ST_TOP_QT_PTR(s)     (&ST_TOP_QT(s)) /* ptr to top qt */
#define ST_BOTTOM_QT_PTR(s)  (&ST_BOTTOM_QT(s)) /* ptr to bottom qt*/

#define ST_NTH_V(s,n,w)        (stDefault_base[stBase_verts[n][w]])
#define ST_ROOT_QT(s,n)        QT_NTH_CHILD(ST_QT(s,n),ST_INDEX(n))

#define ST_CLEAR_QT(st)      (ST_TOP_QT(st)=EMPTY,ST_BOTTOM_QT(st)=EMPTY)
#define ST_INIT_QT(st)      (QT_CLEAR_CHILDREN(ST_TOP_QT(st)), \
                                QT_CLEAR_CHILDREN(ST_BOTTOM_QT(st)))

#define ST_CLEAR_FLAGS(s)       qtClearAllFlags()

/* Point location based on coordinate signs */ 
#define stLocate_root(p) (((p)[2]>0.0?0:4)|((p)[1]>0.0?0:2)|((p)[0]>0.0?0:1))
#define stClear(st)    stInit(st)

#define ST_CLIP_VERTS 16
/* STREE functions
void stInit(STREE *st,FVECT  center)
          Initializes an stree structure with origin 'center': 
          Frees existing quadtrees hanging off of the roots

STREE *stAlloc(STREE *st)
         Allocates a stree structure  and creates octahedron base 

         
QUADTREE stPoint_locate(STREE *st,FVECT p)
         Returns quadtree leaf node containing point 'p'. 

int stAdd_tri(STREE *st,int id,FVECT t0,t1,t2)
         Add triangle 'id' with coordinates 't0,t1,t2' to the stree: returns
         FALSE on error, TRUE otherwise
         
int stRemove_tri(STREE *st,int id,FVECT t0,t1,t2)
         Removes triangle 'id' with coordinates 't0,t1,t2' from stree: returns
         FALSE on error, TRUE otherwise
         
int stTrace_ray(STREE *st,FVECT orig,dir,int (*func)(),int *arg1,*arg2)
        Trace ray 'orig-dir' through stree and apply 'func(arg1,arg2)' at each
        node that it intersects

int stApply_to_tri(STREE *st,FVECT t0,t1,t2,int (*edge_func)(),
        (*tri_func)(),int arg1,*arg2)   
   Visit nodes intersected by tri 't0,t1,t2'.Apply 'edge_func(arg1,arg2,arg3)',
   to those nodes intersected by edges, and interior_func to ALL nodes:
   ie some Nodes  will be visited more than once
*/

extern int stBase_verts[8][3];
extern FVECT stDefault_base[6];
extern STREE *stAlloc();
extern QUADTREE stPoint_locate();


Revision:	3.5
Committed:	Thu Jun 10 15:22:24 1999 UTC (24 years, 10 months ago) by gwlarson
Content type:	text/plain
Branch:	MAIN
Changes since 3.4:	+3 -36 lines
Log Message:	Implemented sample quadtree in place of triangle quadtree Made geometric predicates more robust Added #define LORES which utilizes a single precision floating point sample array, the default is a double sample array Added topology DEBUG commands (for DEBUG > 1) Made code optimizations
#	User	Rev	Content
1	gwlarson	3.1	/* Copyright (c) 1998 Silicon Graphics, Inc. */
2
3			/* SCCSid "$SunId$ SGI" */
4
5			/*
6			* sm_stree.h - header file for spherical quadtree code:
7			*
8			*/
9
10	gwlarson	3.4	#define STR_INDEX(s) (stRoot_indices[(s)])
11			#define STR_NTH_INDEX(s,n) (stRoot_indices[(s)][(n)])
12	gwlarson	3.1
13	gwlarson	3.3	#define ST_NUM_ROOT_NODES 8
14	gwlarson	3.1
15	gwlarson	3.4
16
17	gwlarson	3.3	/* The base is an octahedron: Each face contains a planar quadtree. At
18			the root level, the "top" (positive y) four faces, and bottom four faces
19			are stored together:forming two root quadtree nodes
20			*/
21	gwlarson	3.1
22			typedef struct _STREE {
23	gwlarson	3.4	QUADTREE qt[2]; /* root[0]= top four faces, root[1]=bottom 4 faces*/
24
25	gwlarson	3.1	}STREE;
26
27
28	gwlarson	3.3	#define ST_BASEI(n) ((n)>>2) /* root index: top or bottom */
29			#define ST_INDEX(n) ((n) & 0x3) /* which child in root */
30	gwlarson	3.4	#define ST_QT(s,i) ((s)->qt[ST_BASEI(i)]) /* top or bottom root*/
31			#define ST_QT_PTR(s,i) (&ST_QT(s,i)) /* ptr to top(0)/bottom(1)root*/
32			#define ST_TOP_QT(s) ((s)->qt[0]) /* top root (y>0)*/
33			#define ST_BOTTOM_QT(s) ((s)->qt[1]) /* bottom qt (y <= 0)*/
34			#define ST_TOP_QT_PTR(s) (&ST_TOP_QT(s)) /* ptr to top qt */
35			#define ST_BOTTOM_QT_PTR(s) (&ST_BOTTOM_QT(s)) /* ptr to bottom qt*/
36
37	gwlarson	3.5	#define ST_NTH_V(s,n,w) (stDefault_base[stBase_verts[n][w]])
38	gwlarson	3.4	#define ST_ROOT_QT(s,n) QT_NTH_CHILD(ST_QT(s,n),ST_INDEX(n))
39
40			#define ST_CLEAR_QT(st) (ST_TOP_QT(st)=EMPTY,ST_BOTTOM_QT(st)=EMPTY)
41			#define ST_INIT_QT(st) (QT_CLEAR_CHILDREN(ST_TOP_QT(st)), \
42			QT_CLEAR_CHILDREN(ST_BOTTOM_QT(st)))
43
44	gwlarson	3.2	#define ST_CLEAR_FLAGS(s) qtClearAllFlags()
45	gwlarson	3.3
46			/* Point location based on coordinate signs */
47	gwlarson	3.4	#define stLocate_root(p) (((p)[2]>0.0?0:4)\|((p)[1]>0.0?0:2)\|((p)[0]>0.0?0:1))
48	gwlarson	3.5	#define stClear(st) stInit(st)
49	gwlarson	3.3
50	gwlarson	3.4	#define ST_CLIP_VERTS 16
51	gwlarson	3.1	/* STREE functions
52	gwlarson	3.3	void stInit(STREE *st,FVECT center)
53			Initializes an stree structure with origin 'center':
54			Frees existing quadtrees hanging off of the roots
55	gwlarson	3.1
56	gwlarson	3.3	STREE stAlloc(STREE st)
57			Allocates a stree structure and creates octahedron base
58	gwlarson	3.1
59	gwlarson	3.3
60			QUADTREE stPoint_locate(STREE *st,FVECT p)
61			Returns quadtree leaf node containing point 'p'.
62	gwlarson	3.1
63	gwlarson	3.3	int stAdd_tri(STREE *st,int id,FVECT t0,t1,t2)
64			Add triangle 'id' with coordinates 't0,t1,t2' to the stree: returns
65			FALSE on error, TRUE otherwise
66
67			int stRemove_tri(STREE *st,int id,FVECT t0,t1,t2)
68			Removes triangle 'id' with coordinates 't0,t1,t2' from stree: returns
69			FALSE on error, TRUE otherwise
70
71			int stTrace_ray(STREE st,FVECT orig,dir,int (func)(),int arg1,arg2)
72			Trace ray 'orig-dir' through stree and apply 'func(arg1,arg2)' at each
73			node that it intersects
74	gwlarson	3.1
75	gwlarson	3.3	int stApply_to_tri(STREE st,FVECT t0,t1,t2,int (edge_func)(),
76			(tri_func)(),int arg1,arg2)
77			Visit nodes intersected by tri 't0,t1,t2'.Apply 'edge_func(arg1,arg2,arg3)',
78			to those nodes intersected by edges, and interior_func to ALL nodes:
79			ie some Nodes will be visited more than once
80	gwlarson	3.1	*/
81
82	gwlarson	3.3	extern int stBase_verts[8][3];
83	gwlarson	3.5	extern FVECT stDefault_base[6];
84	gwlarson	3.2	extern STREE *stAlloc();
85	gwlarson	3.3	extern QUADTREE stPoint_locate();
86	gwlarson	3.1
87
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90