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Warning, /include/Geant4/tools/glutess/priorityq is written in an unsupported language. File is not indexed.

0001 // see license file for original license.
0002 
0003 #ifndef tools_glutess_priorityq
0004 #define tools_glutess_priorityq
0005 
0006 #include <climits>              /* LONG_MAX */
0007 #include "memalloc"
0008 
0009 /* Include all the code for the regular heap-based queue here. */
0010 
0011 /////////////////////////////////////////////////////////////////
0012 //#include "priorityq-heap.ic"
0013 //#include "priorityq-heap"
0014 
0015 /* Use #define's so that another heap implementation can use this one */
0016 
0017 #define PQkey                   PQHeapKey
0018 #define PQhandle                PQHeapHandle
0019 #define PriorityQ               PriorityQHeap
0020 
0021 #define pqNewPriorityQ(leq)     __gl_pqHeapNewPriorityQ(leq)
0022 #define pqDeletePriorityQ(pq)   __gl_pqHeapDeletePriorityQ(pq)
0023 
0024 /* The basic operations are insertion of a new key (pqInsert),
0025  * and examination/extraction of a key whose value is minimum
0026  * (pqMinimum/pqExtractMin).  Deletion is also allowed (pqDelete);
0027  * for this purpose pqInsert returns a "handle" which is supplied
0028  * as the argument.
0029  *
0030  * An initial heap may be created efficiently by calling pqInsert
0031  * repeatedly, then calling pqInit.  In any case pqInit must be called
0032  * before any operations other than pqInsert are used.
0033  *
0034  * If the heap is empty, pqMinimum/pqExtractMin will return a NULL key.
0035  * This may also be tested with pqIsEmpty.
0036  */
0037 #define pqInit(pq)              __gl_pqHeapInit(pq)
0038 #define pqInsert(pq,key)        __gl_pqHeapInsert(pq,key)
0039 #define pqMinimum(pq)           __gl_pqHeapMinimum(pq)
0040 #define pqExtractMin(pq)        __gl_pqHeapExtractMin(pq)
0041 #define pqDelete(pq,handle)     __gl_pqHeapDelete(pq,handle)
0042 #define pqIsEmpty(pq)           __gl_pqHeapIsEmpty(pq)
0043 
0044 /* Since we support deletion the data structure is a little more
0045  * complicated than an ordinary heap.  "nodes" is the heap itself;
0046  * active nodes are stored in the range 1..pq->size.  When the
0047  * heap exceeds its allocated size (pq->max), its size doubles.
0048  * The children of node i are nodes 2i and 2i+1.
0049  *
0050  * Each node stores an index into an array "handles".  Each handle
0051  * stores a key, plus a pointer back to the node which currently
0052  * represents that key (ie. nodes[handles[i].node].handle == i).
0053  */
0054 
0055 typedef void *PQkey;
0056 typedef long PQhandle;
0057 typedef struct PriorityQ PriorityQ;
0058 
0059 typedef struct { PQhandle handle; } PQnode;
0060 typedef struct { PQkey key; PQhandle node; } PQhandleElem;
0061 
0062 struct PriorityQ {
0063   PQnode        *nodes;
0064   PQhandleElem  *handles;
0065   long          size, max;
0066   PQhandle      freeList;
0067   int           initialized;
0068   int           (*leq)(PQkey key1, PQkey key2);
0069 };
0070   
0071 #define __gl_pqHeapMinimum(pq)  ((pq)->handles[(pq)->nodes[1].handle].key)
0072 #define __gl_pqHeapIsEmpty(pq)  ((pq)->size == 0)
0073 
0074 /////////////////////////////////////////////////////////////////
0075 /////////////////////////////////////////////////////////////////
0076 //#define INIT_SIZE 32
0077 inline long INIT_SIZE() {
0078   static const long s_value = 32;
0079   return s_value;
0080 }
0081 
0082 /* Violates modularity, but a little faster */
0083 #include "geom"
0084 #define LEQ(x,y)        VertLeq((GLUvertex *)x, (GLUvertex *)y)
0085 
0086 /* really __gl_pqHeapNewPriorityQ */
0087 inline PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) )
0088 {
0089   PriorityQ *pq = (PriorityQ *)memAlloc( sizeof( PriorityQ ));
0090   if (pq == NULL) return NULL;
0091 
0092   pq->size = 0;
0093   pq->max = INIT_SIZE();
0094   pq->nodes = (PQnode *)memAlloc( (INIT_SIZE() + 1) * sizeof(pq->nodes[0]) );
0095   if (pq->nodes == NULL) {
0096      memFree(pq);
0097      return NULL;
0098   }
0099 
0100   pq->handles = (PQhandleElem *)memAlloc( (INIT_SIZE() + 1) * sizeof(pq->handles[0]) );
0101   if (pq->handles == NULL) {
0102      memFree(pq->nodes);
0103      memFree(pq);
0104      return NULL;
0105   }
0106 
0107   pq->initialized = TOOLS_GLU_FALSE;
0108   pq->freeList = 0;
0109   pq->leq = leq;
0110 
0111   pq->nodes[1].handle = 1;      /* so that Minimum() returns NULL */
0112   pq->handles[1].key = NULL;
0113   return pq;
0114 }
0115 
0116 /* really __gl_pqHeapDeletePriorityQ */
0117 inline void pqDeletePriorityQ( PriorityQ *pq )
0118 {
0119   memFree( pq->handles );
0120   memFree( pq->nodes );
0121   memFree( pq );
0122 }
0123 
0124 
0125 inline/*static*/ void static_FloatDown( PriorityQ *pq, long curr )
0126 {
0127   PQnode *n = pq->nodes;
0128   PQhandleElem *h = pq->handles;
0129   PQhandle hCurr, hChild;
0130   long child;
0131 
0132   hCurr = n[curr].handle;
0133   for( ;; ) {
0134     child = curr << 1;
0135     if( child < pq->size && LEQ( h[n[child+1].handle].key,
0136                                  h[n[child].handle].key )) {
0137       ++child;
0138     }
0139 
0140     assert(child <= pq->max);
0141 
0142     hChild = n[child].handle;
0143     if( child > pq->size || LEQ( h[hCurr].key, h[hChild].key )) {
0144       n[curr].handle = hCurr;
0145       h[hCurr].node = curr;
0146       break;
0147     }
0148     n[curr].handle = hChild;
0149     h[hChild].node = curr;
0150     curr = child;
0151   }
0152 }
0153 
0154 
0155 inline/*static*/ void static_FloatUp( PriorityQ *pq, long curr )
0156 {
0157   PQnode *n = pq->nodes;
0158   PQhandleElem *h = pq->handles;
0159   PQhandle hCurr, hParent;
0160   long parent;
0161 
0162   hCurr = n[curr].handle;
0163   for( ;; ) {
0164     parent = curr >> 1;
0165     hParent = n[parent].handle;
0166     if( parent == 0 || LEQ( h[hParent].key, h[hCurr].key )) {
0167       n[curr].handle = hCurr;
0168       h[hCurr].node = curr;
0169       break;
0170     }
0171     n[curr].handle = hParent;
0172     h[hParent].node = curr;
0173     curr = parent;
0174   }
0175 }
0176 
0177 /* really __gl_pqHeapInit */
0178 inline void pqInit( PriorityQ *pq )
0179 {
0180   long i;
0181 
0182   /* This method of building a heap is O(n), rather than O(n lg n). */
0183 
0184   for( i = pq->size; i >= 1; --i ) {
0185     static_FloatDown( pq, i );
0186   }
0187   pq->initialized = TOOLS_GLU_TRUE;
0188 }
0189 
0190 /* really __gl_pqHeapInsert */
0191 /* returns LONG_MAX iff out of memory */
0192 inline PQhandle pqInsert( PriorityQ *pq, PQkey keyNew )
0193 {
0194   long curr;
0195   PQhandle free;
0196 
0197   curr = ++ pq->size;
0198   if( (curr*2) > pq->max ) {
0199     PQnode *saveNodes= pq->nodes;
0200     PQhandleElem *saveHandles= pq->handles;
0201 
0202     /* If the heap overflows, double its size. */
0203     pq->max <<= 1;
0204     pq->nodes = (PQnode *)memRealloc( pq->nodes, 
0205                                      (size_t) 
0206                                      ((pq->max + 1) * sizeof( pq->nodes[0] )));
0207     if (pq->nodes == NULL) {
0208        pq->nodes = saveNodes;   /* restore ptr to free upon return */
0209        return LONG_MAX;
0210     }
0211     pq->handles = (PQhandleElem *)memRealloc( pq->handles,
0212                                              (size_t)
0213                                               ((pq->max + 1) * 
0214                                                sizeof( pq->handles[0] )));
0215     if (pq->handles == NULL) {
0216        pq->handles = saveHandles; /* restore ptr to free upon return */
0217        return LONG_MAX;
0218     }
0219   }
0220 
0221   if( pq->freeList == 0 ) {
0222     free = curr;
0223   } else {
0224     free = pq->freeList;
0225     pq->freeList = pq->handles[free].node;
0226   }
0227 
0228   pq->nodes[curr].handle = free;
0229   pq->handles[free].node = curr;
0230   pq->handles[free].key = keyNew;
0231 
0232   if( pq->initialized ) {
0233     static_FloatUp( pq, curr );
0234   }
0235   assert(free != LONG_MAX);
0236   return free;
0237 }
0238 
0239 /* really __gl_pqHeapExtractMin */
0240 inline PQkey pqExtractMin( PriorityQ *pq )
0241 {
0242   PQnode *n = pq->nodes;
0243   PQhandleElem *h = pq->handles;
0244   PQhandle hMin = n[1].handle;
0245   PQkey min = h[hMin].key;
0246 
0247   if( pq->size > 0 ) {
0248     n[1].handle = n[pq->size].handle;
0249     h[n[1].handle].node = 1;
0250 
0251     h[hMin].key = NULL;
0252     h[hMin].node = pq->freeList;
0253     pq->freeList = hMin;
0254 
0255     if( -- pq->size > 0 ) {
0256       static_FloatDown( pq, 1 );
0257     }
0258   }
0259   return min;
0260 }
0261 
0262 /* really __gl_pqHeapDelete */
0263 inline void pqDelete( PriorityQ *pq, PQhandle hCurr )
0264 {
0265   PQnode *n = pq->nodes;
0266   PQhandleElem *h = pq->handles;
0267   long curr;
0268 
0269   assert( hCurr >= 1 && hCurr <= pq->max && h[hCurr].key != NULL );
0270 
0271   curr = h[hCurr].node;
0272   n[curr].handle = n[pq->size].handle;
0273   h[n[curr].handle].node = curr;
0274 
0275   if( curr <= -- pq->size ) {
0276     if( curr <= 1 || LEQ( h[n[curr>>1].handle].key, h[n[curr].handle].key )) {
0277       static_FloatDown( pq, curr );
0278     } else {
0279       static_FloatUp( pq, curr );
0280     }
0281   }
0282   h[hCurr].key = NULL;
0283   h[hCurr].node = pq->freeList;
0284   pq->freeList = hCurr;
0285 }
0286 
0287 /* Now redefine all the function names to map to their "Sort" versions. */
0288 
0289 /////////////////////////////////////////////////////////////////
0290 //#include "priorityq-sort"
0291 
0292 #undef PQkey
0293 #undef PQhandle
0294 #undef PriorityQ
0295 #undef pqNewPriorityQ
0296 #undef pqDeletePriorityQ
0297 #undef pqInit
0298 #undef pqInsert
0299 #undef pqMinimum
0300 #undef pqExtractMin
0301 #undef pqDelete
0302 #undef pqIsEmpty
0303 
0304 /* Use #define's so that another heap implementation can use this one */
0305 
0306 #define PQkey                   PQSortKey
0307 #define PQhandle                PQSortHandle
0308 #define PriorityQ               PriorityQSort
0309 
0310 #define pqNewPriorityQ(leq)     __gl_pqSortNewPriorityQ(leq)
0311 #define pqDeletePriorityQ(pq)   __gl_pqSortDeletePriorityQ(pq)
0312 
0313 /* The basic operations are insertion of a new key (pqInsert),
0314  * and examination/extraction of a key whose value is minimum
0315  * (pqMinimum/pqExtractMin).  Deletion is also allowed (pqDelete);
0316  * for this purpose pqInsert returns a "handle" which is supplied
0317  * as the argument.
0318  *
0319  * An initial heap may be created efficiently by calling pqInsert
0320  * repeatedly, then calling pqInit.  In any case pqInit must be called
0321  * before any operations other than pqInsert are used.
0322  *
0323  * If the heap is empty, pqMinimum/pqExtractMin will return a NULL key.
0324  * This may also be tested with pqIsEmpty.
0325  */
0326 #define pqInit(pq)              __gl_pqSortInit(pq)
0327 #define pqInsert(pq,key)        __gl_pqSortInsert(pq,key)
0328 #define pqMinimum(pq)           __gl_pqSortMinimum(pq)
0329 #define pqExtractMin(pq)        __gl_pqSortExtractMin(pq)
0330 #define pqDelete(pq,handle)     __gl_pqSortDelete(pq,handle)
0331 #define pqIsEmpty(pq)           __gl_pqSortIsEmpty(pq)
0332 
0333 
0334 /* Since we support deletion the data structure is a little more
0335  * complicated than an ordinary heap.  "nodes" is the heap itself;
0336  * active nodes are stored in the range 1..pq->size.  When the
0337  * heap exceeds its allocated size (pq->max), its size doubles.
0338  * The children of node i are nodes 2i and 2i+1.
0339  *
0340  * Each node stores an index into an array "handles".  Each handle
0341  * stores a key, plus a pointer back to the node which currently
0342  * represents that key (ie. nodes[handles[i].node].handle == i).
0343  */
0344 
0345 typedef PQHeapKey PQkey;
0346 typedef PQHeapHandle PQhandle;
0347 typedef struct PriorityQ PriorityQ;
0348 
0349 struct PriorityQ {
0350   PriorityQHeap *heap;
0351   PQkey         *keys;
0352   PQkey         **order;
0353   PQhandle      size, max;
0354   int           initialized;
0355   int           (*leq)(PQkey key1, PQkey key2);
0356 };
0357   
0358 /* really __gl_pqSortNewPriorityQ */
0359 inline PriorityQ *pqNewPriorityQ( int (*leq)(PQkey key1, PQkey key2) )
0360 {
0361   PriorityQ *pq = (PriorityQ *)memAlloc( sizeof( PriorityQ ));
0362   if (pq == NULL) return NULL;
0363 
0364   pq->heap = __gl_pqHeapNewPriorityQ( leq );
0365   if (pq->heap == NULL) {
0366      memFree(pq);
0367      return NULL;
0368   }
0369 
0370   pq->keys = (PQHeapKey *)memAlloc( INIT_SIZE() * sizeof(pq->keys[0]) );
0371   if (pq->keys == NULL) {
0372      __gl_pqHeapDeletePriorityQ(pq->heap);
0373      memFree(pq);
0374      return NULL;
0375   }
0376 
0377   pq->size = 0;
0378   pq->max = INIT_SIZE();
0379   pq->initialized = TOOLS_GLU_FALSE;
0380   pq->leq = leq;
0381   return pq;
0382 }
0383 
0384 /* really __gl_pqSortDeletePriorityQ */
0385 inline void pqDeletePriorityQ( PriorityQ *pq )
0386 {
0387   assert(pq != NULL); 
0388   if (pq->heap != NULL) __gl_pqHeapDeletePriorityQ( pq->heap );
0389   if (pq->order != NULL) memFree( pq->order );
0390   if (pq->keys != NULL) memFree( pq->keys );
0391   memFree( pq );
0392 }
0393 
0394 
0395 #define LT(x,y)         (! LEQ(y,x))
0396 #define GT(x,y)         (! LEQ(x,y))
0397 //#define pq_Swap(a,b)  if(1){PQkey *tmp = *a; *a = *b; *b = tmp;}else
0398 #define pq_Swap(a,b)    do{PQkey *tmp = *a; *a = *b; *b = tmp;} while(false)
0399 
0400 /* really __gl_pqSortInit */
0401 inline int pqInit( PriorityQ *pq )
0402 {
0403   PQkey **p, **r, **i, **j, *piv;
0404   struct { PQkey **p, **r; } Stack[50], *top = Stack;
0405   unsigned long seed = 2016473283;
0406 
0407   /* Create an array of indirect pointers to the keys, so that we
0408    * the handles we have returned are still valid.
0409    */
0410 /*
0411   pq->order = (PQHeapKey **)memAlloc( (size_t)
0412                                   (pq->size * sizeof(pq->order[0])) );
0413 */
0414   pq->order = (PQHeapKey **)memAlloc( (size_t)
0415                                   ((pq->size+1) * sizeof(pq->order[0])) );
0416 /* the previous line is a patch to compensate for the fact that IBM */
0417 /* machines return a null on a malloc of zero bytes (unlike SGI),   */
0418 /* so we have to put in this defense to guard against a memory      */
0419 /* fault four lines down. from fossum@austin.ibm.com.               */
0420   if (pq->order == NULL) return 0;
0421 
0422   p = pq->order;
0423   r = p + pq->size - 1;
0424   for( piv = pq->keys, i = p; i <= r; ++piv, ++i ) {
0425     *i = piv;
0426   }
0427 
0428   /* Sort the indirect pointers in descending order,
0429    * using randomized Quicksort
0430    */
0431   top->p = p; top->r = r; ++top;
0432   while( --top >= Stack ) {
0433     p = top->p;
0434     r = top->r;
0435     while( r > p + 10 ) {
0436       seed = seed * 1539415821 + 1;
0437       i = p + seed % (r - p + 1);
0438       piv = *i;
0439       *i = *p;
0440       *p = piv;
0441       i = p - 1;
0442       j = r + 1;
0443       do {
0444         do { ++i; } while( GT( **i, *piv ));
0445         do { --j; } while( LT( **j, *piv ));
0446         pq_Swap( i, j );
0447       } while( i < j );
0448       pq_Swap( i, j );  /* Undo last swap */
0449       if( i - p < r - j ) {
0450         top->p = j+1; top->r = r; ++top;
0451         r = i-1;
0452       } else {
0453         top->p = p; top->r = i-1; ++top;
0454         p = j+1;
0455       }
0456     }
0457     /* Insertion sort small lists */
0458     for( i = p+1; i <= r; ++i ) {
0459       piv = *i;
0460       for( j = i; j > p && LT( **(j-1), *piv ); --j ) {
0461         *j = *(j-1);
0462       }
0463       *j = piv;
0464     }
0465   }
0466   pq->max = pq->size;
0467   pq->initialized = TOOLS_GLU_TRUE;
0468   __gl_pqHeapInit( pq->heap );  /* always succeeds */
0469 
0470 #ifndef NDEBUG
0471   p = pq->order;
0472   r = p + pq->size - 1;
0473   for( i = p; i < r; ++i ) {
0474     assert( LEQ( **(i+1), **i ));
0475   }
0476 #endif
0477 
0478   return 1;
0479 }
0480 
0481 /* really __gl_pqSortInsert */
0482 /* returns LONG_MAX iff out of memory */ 
0483 inline PQhandle pqInsert( PriorityQ *pq, PQkey keyNew )
0484 {
0485   long curr;
0486 
0487   if( pq->initialized ) {
0488     return __gl_pqHeapInsert( pq->heap, keyNew );
0489   }
0490   curr = pq->size;
0491   if( ++ pq->size >= pq->max ) {
0492     PQkey *saveKey= pq->keys;
0493 
0494     /* If the heap overflows, double its size. */
0495     pq->max <<= 1;
0496     pq->keys = (PQHeapKey *)memRealloc( pq->keys, 
0497                                         (size_t)
0498                                          (pq->max * sizeof( pq->keys[0] )));
0499     if (pq->keys == NULL) {     
0500        pq->keys = saveKey;      /* restore ptr to free upon return */
0501        return LONG_MAX;
0502     }
0503   }
0504   assert(curr != LONG_MAX);     
0505   pq->keys[curr] = keyNew;
0506 
0507   /* Negative handles index the sorted array. */
0508   return -(curr+1);
0509 }
0510 
0511 /* really __gl_pqSortExtractMin */
0512 inline PQkey pqExtractMin( PriorityQ *pq )
0513 {
0514   PQkey sortMin, heapMin;
0515 
0516   if( pq->size == 0 ) {
0517     return __gl_pqHeapExtractMin( pq->heap );
0518   }
0519   sortMin = *(pq->order[pq->size-1]);
0520   if( ! __gl_pqHeapIsEmpty( pq->heap )) {
0521     heapMin = __gl_pqHeapMinimum( pq->heap );
0522     if( LEQ( heapMin, sortMin )) {
0523       return __gl_pqHeapExtractMin( pq->heap );
0524     }
0525   }
0526   do {
0527     -- pq->size;
0528   } while( pq->size > 0 && *(pq->order[pq->size-1]) == NULL );
0529   return sortMin;
0530 }
0531 
0532 /* really __gl_pqSortMinimum */
0533 inline PQkey pqMinimum( PriorityQ *pq )
0534 {
0535   PQkey sortMin, heapMin;
0536 
0537   if( pq->size == 0 ) {
0538     return __gl_pqHeapMinimum( pq->heap );
0539   }
0540   sortMin = *(pq->order[pq->size-1]);
0541   if( ! __gl_pqHeapIsEmpty( pq->heap )) {
0542     heapMin = __gl_pqHeapMinimum( pq->heap );
0543     if( LEQ( heapMin, sortMin )) {
0544       return heapMin;
0545     }
0546   }
0547   return sortMin;
0548 }
0549 
0550 /* really __gl_pqSortIsEmpty */
0551 inline int pqIsEmpty( PriorityQ *pq )
0552 {
0553   return (pq->size == 0) && __gl_pqHeapIsEmpty( pq->heap );
0554 }
0555 
0556 /* really __gl_pqSortDelete */
0557 inline void pqDelete( PriorityQ *pq, PQhandle curr )
0558 {
0559   if( curr >= 0 ) {
0560     __gl_pqHeapDelete( pq->heap, curr );
0561     return;
0562   }
0563   curr = -(curr+1);
0564   assert( curr < pq->max && pq->keys[curr] != NULL );
0565 
0566   pq->keys[curr] = NULL;
0567   while( pq->size > 0 && *(pq->order[pq->size-1]) == NULL ) {
0568     -- pq->size;
0569   }
0570 }
0571 
0572 #endif