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/* Copyright (c) 1998 Silicon Graphics, Inc. */ |
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/* SCCSid "$SunId$ SGI" */ |
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/* |
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* sm_qtree.h - header file for routines using spherical quadtrees. |
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* |
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* adapted from octree.h |
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*/ |
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/* |
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* An quadtree is expressed as an integer which is either |
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* an index to 4 other nodes, the empty tree, or an index |
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* to a set of objects. If the quadtree has a value: |
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* |
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* > -1: it is an index to four other nodes. |
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* |
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* -1: it is empty |
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* |
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* < -1: it is an index to a set of objects |
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*/ |
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#define QUADTREE int |
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#define EMPTY (-1) |
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#define QT_IS_EMPTY(qt) ((qt) == EMPTY) |
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#define QT_IS_LEAF(qt) ((qt) < EMPTY) |
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#define QT_IS_TREE(qt) ((qt) > EMPTY) |
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#define QT_INDEX(qt) (-(qt)-2) /* quadtree node from set */ |
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#define QT_SET_INDEX(i) (-((i)+2)) /* object set from node */ |
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#define QT_BLOCK(qt) ((qt)>>8) /* quadtree block index */ |
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#define QT_BLOCK_INDEX(qt) (((qt)&0377)<<2) /* quadtree index in block */ |
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#ifndef QT_MAX_BLK |
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#ifdef BIGMEM |
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#define QT_MAX_BLK 65535 /* maximum quadtree block */ |
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#else |
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#define QT_MAX_BLK 8191 /* maximum quadtree block */ |
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#endif |
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#endif |
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#define QT_NTH_CHILD(qt,br) (quad_block[QT_BLOCK(qt)][QT_BLOCK_INDEX(qt)+br]) |
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#define QT_NTH_CHILD_PTR(qt,br) \ |
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(&(quad_block[QT_BLOCK(qt)][QT_BLOCK_INDEX(qt)+br])) |
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#define QT_CLEAR_CHILDREN(qt) (QT_NTH_CHILD(qt,0)=EMPTY, \ |
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QT_NTH_CHILD(qt,1)=EMPTY,QT_NTH_CHILD(qt,2)=EMPTY,QT_NTH_CHILD(qt,3)=EMPTY) |
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#if 0 |
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#define QT_EMPTY 0 |
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#define QT_FULL 1 |
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#define QT_TREE 2 |
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#endif |
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/* OBJECT SET CODE */ |
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#define QT_SET_CNT(s) ((s)[0]) |
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#define QT_SET_NTH_ELEM(s,n) ((s)[(n)]) |
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#define QT_CLEAR_SET(s) ((s)[0] = 0) |
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#define QT_SET_NEXT_ELEM(p) (*(p)++) |
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#define QT_SET_PTR(s) (&((s)[1])) |
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#define QT_MAX_SET MAXSET |
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#define MAXCSET MAXSET*2 |
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#ifndef QT_SET_THRESHOLD |
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#define QT_SET_THRESHOLD 30 |
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#endif |
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#ifndef QT_MAX_LEVELS |
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#define QT_MAX_LEVELS 17 |
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#endif |
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#define QT_BLOCK_SIZE 256 |
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extern QUADTREE qtnewleaf(), qtaddelem(), qtdelelem(); |
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extern QUADTREE *quad_block[QT_MAX_BLK]; /* quadtree blocks */ |
