| 1 |
/****************************************************************************** |
| 2 |
* $Id$ |
| 3 |
* |
| 4 |
* Project: Shapelib |
| 5 |
* Purpose: Implementation of quadtree building and searching functions. |
| 6 |
* Author: Frank Warmerdam, [email protected] |
| 7 |
* |
| 8 |
****************************************************************************** |
| 9 |
* Copyright (c) 1999, Frank Warmerdam |
| 10 |
* |
| 11 |
* This software is available under the following "MIT Style" license, |
| 12 |
* or at the option of the licensee under the LGPL (see LICENSE.LGPL). This |
| 13 |
* option is discussed in more detail in shapelib.html. |
| 14 |
* |
| 15 |
* -- |
| 16 |
* |
| 17 |
* Permission is hereby granted, free of charge, to any person obtaining a |
| 18 |
* copy of this software and associated documentation files (the "Software"), |
| 19 |
* to deal in the Software without restriction, including without limitation |
| 20 |
* the rights to use, copy, modify, merge, publish, distribute, sublicense, |
| 21 |
* and/or sell copies of the Software, and to permit persons to whom the |
| 22 |
* Software is furnished to do so, subject to the following conditions: |
| 23 |
* |
| 24 |
* The above copyright notice and this permission notice shall be included |
| 25 |
* in all copies or substantial portions of the Software. |
| 26 |
* |
| 27 |
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS |
| 28 |
* OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| 29 |
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL |
| 30 |
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| 31 |
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
| 32 |
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER |
| 33 |
* DEALINGS IN THE SOFTWARE. |
| 34 |
****************************************************************************** |
| 35 |
* |
| 36 |
* $Log$ |
| 37 |
* Revision 1.2 2003/10/02 15:15:16 bh |
| 38 |
* Update to shapelib 1.2.10 |
| 39 |
* |
| 40 |
* Revision 1.9 2003/01/28 15:53:41 warmerda |
| 41 |
* Avoid build warnings. |
| 42 |
* |
| 43 |
* Revision 1.8 2002/05/07 13:07:45 warmerda |
| 44 |
* use qsort() - patch from Bernhard Herzog |
| 45 |
* |
| 46 |
* Revision 1.7 2002/01/15 14:36:07 warmerda |
| 47 |
* updated email address |
| 48 |
* |
| 49 |
* Revision 1.6 2001/05/23 13:36:52 warmerda |
| 50 |
* added use of SHPAPI_CALL |
| 51 |
* |
| 52 |
* Revision 1.5 1999/11/05 14:12:05 warmerda |
| 53 |
* updated license terms |
| 54 |
* |
| 55 |
* Revision 1.4 1999/06/02 18:24:21 warmerda |
| 56 |
* added trimming code |
| 57 |
* |
| 58 |
* Revision 1.3 1999/06/02 17:56:12 warmerda |
| 59 |
* added quad'' subnode support for trees |
| 60 |
* |
| 61 |
* Revision 1.2 1999/05/18 19:11:11 warmerda |
| 62 |
* Added example searching capability |
| 63 |
* |
| 64 |
* Revision 1.1 1999/05/18 17:49:20 warmerda |
| 65 |
* New |
| 66 |
* |
| 67 |
*/ |
| 68 |
|
| 69 |
static char rcsid[] = |
| 70 |
"$Id$"; |
| 71 |
|
| 72 |
#include "shapefil.h" |
| 73 |
|
| 74 |
#include <math.h> |
| 75 |
#include <assert.h> |
| 76 |
#include <stdlib.h> |
| 77 |
#include <string.h> |
| 78 |
|
| 79 |
#ifndef TRUE |
| 80 |
# define TRUE 1 |
| 81 |
# define FALSE 0 |
| 82 |
#endif |
| 83 |
|
| 84 |
|
| 85 |
/* -------------------------------------------------------------------- */ |
| 86 |
/* If the following is 0.5, nodes will be split in half. If it */ |
| 87 |
/* is 0.6 then each subnode will contain 60% of the parent */ |
| 88 |
/* node, with 20% representing overlap. This can be help to */ |
| 89 |
/* prevent small objects on a boundary from shifting too high */ |
| 90 |
/* up the tree. */ |
| 91 |
/* -------------------------------------------------------------------- */ |
| 92 |
|
| 93 |
#define SHP_SPLIT_RATIO 0.55 |
| 94 |
|
| 95 |
/************************************************************************/ |
| 96 |
/* SfRealloc() */ |
| 97 |
/* */ |
| 98 |
/* A realloc cover function that will access a NULL pointer as */ |
| 99 |
/* a valid input. */ |
| 100 |
/************************************************************************/ |
| 101 |
|
| 102 |
static void * SfRealloc( void * pMem, int nNewSize ) |
| 103 |
|
| 104 |
{ |
| 105 |
if( pMem == NULL ) |
| 106 |
return( (void *) malloc(nNewSize) ); |
| 107 |
else |
| 108 |
return( (void *) realloc(pMem,nNewSize) ); |
| 109 |
} |
| 110 |
|
| 111 |
/************************************************************************/ |
| 112 |
/* SHPTreeNodeInit() */ |
| 113 |
/* */ |
| 114 |
/* Initialize a tree node. */ |
| 115 |
/************************************************************************/ |
| 116 |
|
| 117 |
static SHPTreeNode *SHPTreeNodeCreate( double * padfBoundsMin, |
| 118 |
double * padfBoundsMax ) |
| 119 |
|
| 120 |
{ |
| 121 |
SHPTreeNode *psTreeNode; |
| 122 |
|
| 123 |
psTreeNode = (SHPTreeNode *) malloc(sizeof(SHPTreeNode)); |
| 124 |
|
| 125 |
psTreeNode->nShapeCount = 0; |
| 126 |
psTreeNode->panShapeIds = NULL; |
| 127 |
psTreeNode->papsShapeObj = NULL; |
| 128 |
|
| 129 |
psTreeNode->nSubNodes = 0; |
| 130 |
|
| 131 |
if( padfBoundsMin != NULL ) |
| 132 |
memcpy( psTreeNode->adfBoundsMin, padfBoundsMin, sizeof(double) * 4 ); |
| 133 |
|
| 134 |
if( padfBoundsMax != NULL ) |
| 135 |
memcpy( psTreeNode->adfBoundsMax, padfBoundsMax, sizeof(double) * 4 ); |
| 136 |
|
| 137 |
return psTreeNode; |
| 138 |
} |
| 139 |
|
| 140 |
|
| 141 |
/************************************************************************/ |
| 142 |
/* SHPCreateTree() */ |
| 143 |
/************************************************************************/ |
| 144 |
|
| 145 |
SHPTree SHPAPI_CALL1(*) |
| 146 |
SHPCreateTree( SHPHandle hSHP, int nDimension, int nMaxDepth, |
| 147 |
double *padfBoundsMin, double *padfBoundsMax ) |
| 148 |
|
| 149 |
{ |
| 150 |
SHPTree *psTree; |
| 151 |
|
| 152 |
if( padfBoundsMin == NULL && hSHP == NULL ) |
| 153 |
return NULL; |
| 154 |
|
| 155 |
/* -------------------------------------------------------------------- */ |
| 156 |
/* Allocate the tree object */ |
| 157 |
/* -------------------------------------------------------------------- */ |
| 158 |
psTree = (SHPTree *) malloc(sizeof(SHPTree)); |
| 159 |
|
| 160 |
psTree->hSHP = hSHP; |
| 161 |
psTree->nMaxDepth = nMaxDepth; |
| 162 |
psTree->nDimension = nDimension; |
| 163 |
|
| 164 |
/* -------------------------------------------------------------------- */ |
| 165 |
/* If no max depth was defined, try to select a reasonable one */ |
| 166 |
/* that implies approximately 8 shapes per node. */ |
| 167 |
/* -------------------------------------------------------------------- */ |
| 168 |
if( psTree->nMaxDepth == 0 && hSHP != NULL ) |
| 169 |
{ |
| 170 |
int nMaxNodeCount = 1; |
| 171 |
int nShapeCount; |
| 172 |
|
| 173 |
SHPGetInfo( hSHP, &nShapeCount, NULL, NULL, NULL ); |
| 174 |
while( nMaxNodeCount*4 < nShapeCount ) |
| 175 |
{ |
| 176 |
psTree->nMaxDepth += 1; |
| 177 |
nMaxNodeCount = nMaxNodeCount * 2; |
| 178 |
} |
| 179 |
} |
| 180 |
|
| 181 |
/* -------------------------------------------------------------------- */ |
| 182 |
/* Allocate the root node. */ |
| 183 |
/* -------------------------------------------------------------------- */ |
| 184 |
psTree->psRoot = SHPTreeNodeCreate( padfBoundsMin, padfBoundsMax ); |
| 185 |
|
| 186 |
/* -------------------------------------------------------------------- */ |
| 187 |
/* Assign the bounds to the root node. If none are passed in, */ |
| 188 |
/* use the bounds of the provided file otherwise the create */ |
| 189 |
/* function will have already set the bounds. */ |
| 190 |
/* -------------------------------------------------------------------- */ |
| 191 |
if( padfBoundsMin == NULL ) |
| 192 |
{ |
| 193 |
SHPGetInfo( hSHP, NULL, NULL, |
| 194 |
psTree->psRoot->adfBoundsMin, |
| 195 |
psTree->psRoot->adfBoundsMax ); |
| 196 |
} |
| 197 |
|
| 198 |
/* -------------------------------------------------------------------- */ |
| 199 |
/* If we have a file, insert all it's shapes into the tree. */ |
| 200 |
/* -------------------------------------------------------------------- */ |
| 201 |
if( hSHP != NULL ) |
| 202 |
{ |
| 203 |
int iShape, nShapeCount; |
| 204 |
|
| 205 |
SHPGetInfo( hSHP, &nShapeCount, NULL, NULL, NULL ); |
| 206 |
|
| 207 |
for( iShape = 0; iShape < nShapeCount; iShape++ ) |
| 208 |
{ |
| 209 |
SHPObject *psShape; |
| 210 |
|
| 211 |
psShape = SHPReadObject( hSHP, iShape ); |
| 212 |
SHPTreeAddShapeId( psTree, psShape ); |
| 213 |
SHPDestroyObject( psShape ); |
| 214 |
} |
| 215 |
} |
| 216 |
|
| 217 |
return psTree; |
| 218 |
} |
| 219 |
|
| 220 |
/************************************************************************/ |
| 221 |
/* SHPDestroyTreeNode() */ |
| 222 |
/************************************************************************/ |
| 223 |
|
| 224 |
static void SHPDestroyTreeNode( SHPTreeNode * psTreeNode ) |
| 225 |
|
| 226 |
{ |
| 227 |
int i; |
| 228 |
|
| 229 |
for( i = 0; i < psTreeNode->nSubNodes; i++ ) |
| 230 |
{ |
| 231 |
if( psTreeNode->apsSubNode[i] != NULL ) |
| 232 |
SHPDestroyTreeNode( psTreeNode->apsSubNode[i] ); |
| 233 |
} |
| 234 |
|
| 235 |
if( psTreeNode->panShapeIds != NULL ) |
| 236 |
free( psTreeNode->panShapeIds ); |
| 237 |
|
| 238 |
if( psTreeNode->papsShapeObj != NULL ) |
| 239 |
{ |
| 240 |
for( i = 0; i < psTreeNode->nShapeCount; i++ ) |
| 241 |
{ |
| 242 |
if( psTreeNode->papsShapeObj[i] != NULL ) |
| 243 |
SHPDestroyObject( psTreeNode->papsShapeObj[i] ); |
| 244 |
} |
| 245 |
|
| 246 |
free( psTreeNode->papsShapeObj ); |
| 247 |
} |
| 248 |
|
| 249 |
free( psTreeNode ); |
| 250 |
} |
| 251 |
|
| 252 |
/************************************************************************/ |
| 253 |
/* SHPDestroyTree() */ |
| 254 |
/************************************************************************/ |
| 255 |
|
| 256 |
void SHPAPI_CALL |
| 257 |
SHPDestroyTree( SHPTree * psTree ) |
| 258 |
|
| 259 |
{ |
| 260 |
SHPDestroyTreeNode( psTree->psRoot ); |
| 261 |
free( psTree ); |
| 262 |
} |
| 263 |
|
| 264 |
/************************************************************************/ |
| 265 |
/* SHPCheckBoundsOverlap() */ |
| 266 |
/* */ |
| 267 |
/* Do the given boxes overlap at all? */ |
| 268 |
/************************************************************************/ |
| 269 |
|
| 270 |
int SHPAPI_CALL |
| 271 |
SHPCheckBoundsOverlap( double * padfBox1Min, double * padfBox1Max, |
| 272 |
double * padfBox2Min, double * padfBox2Max, |
| 273 |
int nDimension ) |
| 274 |
|
| 275 |
{ |
| 276 |
int iDim; |
| 277 |
|
| 278 |
for( iDim = 0; iDim < nDimension; iDim++ ) |
| 279 |
{ |
| 280 |
if( padfBox2Max[iDim] < padfBox1Min[iDim] ) |
| 281 |
return FALSE; |
| 282 |
|
| 283 |
if( padfBox1Max[iDim] < padfBox2Min[iDim] ) |
| 284 |
return FALSE; |
| 285 |
} |
| 286 |
|
| 287 |
return TRUE; |
| 288 |
} |
| 289 |
|
| 290 |
/************************************************************************/ |
| 291 |
/* SHPCheckObjectContained() */ |
| 292 |
/* */ |
| 293 |
/* Does the given shape fit within the indicated extents? */ |
| 294 |
/************************************************************************/ |
| 295 |
|
| 296 |
static int SHPCheckObjectContained( SHPObject * psObject, int nDimension, |
| 297 |
double * padfBoundsMin, double * padfBoundsMax ) |
| 298 |
|
| 299 |
{ |
| 300 |
if( psObject->dfXMin < padfBoundsMin[0] |
| 301 |
|| psObject->dfXMax > padfBoundsMax[0] ) |
| 302 |
return FALSE; |
| 303 |
|
| 304 |
if( psObject->dfYMin < padfBoundsMin[1] |
| 305 |
|| psObject->dfYMax > padfBoundsMax[1] ) |
| 306 |
return FALSE; |
| 307 |
|
| 308 |
if( nDimension == 2 ) |
| 309 |
return TRUE; |
| 310 |
|
| 311 |
if( psObject->dfZMin < padfBoundsMin[2] |
| 312 |
|| psObject->dfZMax < padfBoundsMax[2] ) |
| 313 |
return FALSE; |
| 314 |
|
| 315 |
if( nDimension == 3 ) |
| 316 |
return TRUE; |
| 317 |
|
| 318 |
if( psObject->dfMMin < padfBoundsMin[3] |
| 319 |
|| psObject->dfMMax < padfBoundsMax[3] ) |
| 320 |
return FALSE; |
| 321 |
|
| 322 |
return TRUE; |
| 323 |
} |
| 324 |
|
| 325 |
/************************************************************************/ |
| 326 |
/* SHPTreeSplitBounds() */ |
| 327 |
/* */ |
| 328 |
/* Split a region into two subregion evenly, cutting along the */ |
| 329 |
/* longest dimension. */ |
| 330 |
/************************************************************************/ |
| 331 |
|
| 332 |
void SHPAPI_CALL |
| 333 |
SHPTreeSplitBounds( double *padfBoundsMinIn, double *padfBoundsMaxIn, |
| 334 |
double *padfBoundsMin1, double * padfBoundsMax1, |
| 335 |
double *padfBoundsMin2, double * padfBoundsMax2 ) |
| 336 |
|
| 337 |
{ |
| 338 |
/* -------------------------------------------------------------------- */ |
| 339 |
/* The output bounds will be very similar to the input bounds, */ |
| 340 |
/* so just copy over to start. */ |
| 341 |
/* -------------------------------------------------------------------- */ |
| 342 |
memcpy( padfBoundsMin1, padfBoundsMinIn, sizeof(double) * 4 ); |
| 343 |
memcpy( padfBoundsMax1, padfBoundsMaxIn, sizeof(double) * 4 ); |
| 344 |
memcpy( padfBoundsMin2, padfBoundsMinIn, sizeof(double) * 4 ); |
| 345 |
memcpy( padfBoundsMax2, padfBoundsMaxIn, sizeof(double) * 4 ); |
| 346 |
|
| 347 |
/* -------------------------------------------------------------------- */ |
| 348 |
/* Split in X direction. */ |
| 349 |
/* -------------------------------------------------------------------- */ |
| 350 |
if( (padfBoundsMaxIn[0] - padfBoundsMinIn[0]) |
| 351 |
> (padfBoundsMaxIn[1] - padfBoundsMinIn[1]) ) |
| 352 |
{ |
| 353 |
double dfRange = padfBoundsMaxIn[0] - padfBoundsMinIn[0]; |
| 354 |
|
| 355 |
padfBoundsMax1[0] = padfBoundsMinIn[0] + dfRange * SHP_SPLIT_RATIO; |
| 356 |
padfBoundsMin2[0] = padfBoundsMaxIn[0] - dfRange * SHP_SPLIT_RATIO; |
| 357 |
} |
| 358 |
|
| 359 |
/* -------------------------------------------------------------------- */ |
| 360 |
/* Otherwise split in Y direction. */ |
| 361 |
/* -------------------------------------------------------------------- */ |
| 362 |
else |
| 363 |
{ |
| 364 |
double dfRange = padfBoundsMaxIn[1] - padfBoundsMinIn[1]; |
| 365 |
|
| 366 |
padfBoundsMax1[1] = padfBoundsMinIn[1] + dfRange * SHP_SPLIT_RATIO; |
| 367 |
padfBoundsMin2[1] = padfBoundsMaxIn[1] - dfRange * SHP_SPLIT_RATIO; |
| 368 |
} |
| 369 |
} |
| 370 |
|
| 371 |
/************************************************************************/ |
| 372 |
/* SHPTreeNodeAddShapeId() */ |
| 373 |
/************************************************************************/ |
| 374 |
|
| 375 |
static int |
| 376 |
SHPTreeNodeAddShapeId( SHPTreeNode * psTreeNode, SHPObject * psObject, |
| 377 |
int nMaxDepth, int nDimension ) |
| 378 |
|
| 379 |
{ |
| 380 |
int i; |
| 381 |
|
| 382 |
/* -------------------------------------------------------------------- */ |
| 383 |
/* If there are subnodes, then consider wiether this object */ |
| 384 |
/* will fit in them. */ |
| 385 |
/* -------------------------------------------------------------------- */ |
| 386 |
if( nMaxDepth > 1 && psTreeNode->nSubNodes > 0 ) |
| 387 |
{ |
| 388 |
for( i = 0; i < psTreeNode->nSubNodes; i++ ) |
| 389 |
{ |
| 390 |
if( SHPCheckObjectContained(psObject, nDimension, |
| 391 |
psTreeNode->apsSubNode[i]->adfBoundsMin, |
| 392 |
psTreeNode->apsSubNode[i]->adfBoundsMax)) |
| 393 |
{ |
| 394 |
return SHPTreeNodeAddShapeId( psTreeNode->apsSubNode[i], |
| 395 |
psObject, nMaxDepth-1, |
| 396 |
nDimension ); |
| 397 |
} |
| 398 |
} |
| 399 |
} |
| 400 |
|
| 401 |
/* -------------------------------------------------------------------- */ |
| 402 |
/* Otherwise, consider creating four subnodes if could fit into */ |
| 403 |
/* them, and adding to the appropriate subnode. */ |
| 404 |
/* -------------------------------------------------------------------- */ |
| 405 |
#if MAX_SUBNODE == 4 |
| 406 |
else if( nMaxDepth > 1 && psTreeNode->nSubNodes == 0 ) |
| 407 |
{ |
| 408 |
double adfBoundsMinH1[4], adfBoundsMaxH1[4]; |
| 409 |
double adfBoundsMinH2[4], adfBoundsMaxH2[4]; |
| 410 |
double adfBoundsMin1[4], adfBoundsMax1[4]; |
| 411 |
double adfBoundsMin2[4], adfBoundsMax2[4]; |
| 412 |
double adfBoundsMin3[4], adfBoundsMax3[4]; |
| 413 |
double adfBoundsMin4[4], adfBoundsMax4[4]; |
| 414 |
|
| 415 |
SHPTreeSplitBounds( psTreeNode->adfBoundsMin, |
| 416 |
psTreeNode->adfBoundsMax, |
| 417 |
adfBoundsMinH1, adfBoundsMaxH1, |
| 418 |
adfBoundsMinH2, adfBoundsMaxH2 ); |
| 419 |
|
| 420 |
SHPTreeSplitBounds( adfBoundsMinH1, adfBoundsMaxH1, |
| 421 |
adfBoundsMin1, adfBoundsMax1, |
| 422 |
adfBoundsMin2, adfBoundsMax2 ); |
| 423 |
|
| 424 |
SHPTreeSplitBounds( adfBoundsMinH2, adfBoundsMaxH2, |
| 425 |
adfBoundsMin3, adfBoundsMax3, |
| 426 |
adfBoundsMin4, adfBoundsMax4 ); |
| 427 |
|
| 428 |
if( SHPCheckObjectContained(psObject, nDimension, |
| 429 |
adfBoundsMin1, adfBoundsMax1) |
| 430 |
|| SHPCheckObjectContained(psObject, nDimension, |
| 431 |
adfBoundsMin2, adfBoundsMax2) |
| 432 |
|| SHPCheckObjectContained(psObject, nDimension, |
| 433 |
adfBoundsMin3, adfBoundsMax3) |
| 434 |
|| SHPCheckObjectContained(psObject, nDimension, |
| 435 |
adfBoundsMin4, adfBoundsMax4) ) |
| 436 |
{ |
| 437 |
psTreeNode->nSubNodes = 4; |
| 438 |
psTreeNode->apsSubNode[0] = SHPTreeNodeCreate( adfBoundsMin1, |
| 439 |
adfBoundsMax1 ); |
| 440 |
psTreeNode->apsSubNode[1] = SHPTreeNodeCreate( adfBoundsMin2, |
| 441 |
adfBoundsMax2 ); |
| 442 |
psTreeNode->apsSubNode[2] = SHPTreeNodeCreate( adfBoundsMin3, |
| 443 |
adfBoundsMax3 ); |
| 444 |
psTreeNode->apsSubNode[3] = SHPTreeNodeCreate( adfBoundsMin4, |
| 445 |
adfBoundsMax4 ); |
| 446 |
|
| 447 |
/* recurse back on this node now that it has subnodes */ |
| 448 |
return( SHPTreeNodeAddShapeId( psTreeNode, psObject, |
| 449 |
nMaxDepth, nDimension ) ); |
| 450 |
} |
| 451 |
} |
| 452 |
#endif /* MAX_SUBNODE == 4 */ |
| 453 |
|
| 454 |
/* -------------------------------------------------------------------- */ |
| 455 |
/* Otherwise, consider creating two subnodes if could fit into */ |
| 456 |
/* them, and adding to the appropriate subnode. */ |
| 457 |
/* -------------------------------------------------------------------- */ |
| 458 |
#if MAX_SUBNODE == 2 |
| 459 |
else if( nMaxDepth > 1 && psTreeNode->nSubNodes == 0 ) |
| 460 |
{ |
| 461 |
double adfBoundsMin1[4], adfBoundsMax1[4]; |
| 462 |
double adfBoundsMin2[4], adfBoundsMax2[4]; |
| 463 |
|
| 464 |
SHPTreeSplitBounds( psTreeNode->adfBoundsMin, psTreeNode->adfBoundsMax, |
| 465 |
adfBoundsMin1, adfBoundsMax1, |
| 466 |
adfBoundsMin2, adfBoundsMax2 ); |
| 467 |
|
| 468 |
if( SHPCheckObjectContained(psObject, nDimension, |
| 469 |
adfBoundsMin1, adfBoundsMax1)) |
| 470 |
{ |
| 471 |
psTreeNode->nSubNodes = 2; |
| 472 |
psTreeNode->apsSubNode[0] = SHPTreeNodeCreate( adfBoundsMin1, |
| 473 |
adfBoundsMax1 ); |
| 474 |
psTreeNode->apsSubNode[1] = SHPTreeNodeCreate( adfBoundsMin2, |
| 475 |
adfBoundsMax2 ); |
| 476 |
|
| 477 |
return( SHPTreeNodeAddShapeId( psTreeNode->apsSubNode[0], psObject, |
| 478 |
nMaxDepth - 1, nDimension ) ); |
| 479 |
} |
| 480 |
else if( SHPCheckObjectContained(psObject, nDimension, |
| 481 |
adfBoundsMin2, adfBoundsMax2) ) |
| 482 |
{ |
| 483 |
psTreeNode->nSubNodes = 2; |
| 484 |
psTreeNode->apsSubNode[0] = SHPTreeNodeCreate( adfBoundsMin1, |
| 485 |
adfBoundsMax1 ); |
| 486 |
psTreeNode->apsSubNode[1] = SHPTreeNodeCreate( adfBoundsMin2, |
| 487 |
adfBoundsMax2 ); |
| 488 |
|
| 489 |
return( SHPTreeNodeAddShapeId( psTreeNode->apsSubNode[1], psObject, |
| 490 |
nMaxDepth - 1, nDimension ) ); |
| 491 |
} |
| 492 |
} |
| 493 |
#endif /* MAX_SUBNODE == 2 */ |
| 494 |
|
| 495 |
/* -------------------------------------------------------------------- */ |
| 496 |
/* If none of that worked, just add it to this nodes list. */ |
| 497 |
/* -------------------------------------------------------------------- */ |
| 498 |
psTreeNode->nShapeCount++; |
| 499 |
|
| 500 |
psTreeNode->panShapeIds = |
| 501 |
SfRealloc( psTreeNode->panShapeIds, |
| 502 |
sizeof(int) * psTreeNode->nShapeCount ); |
| 503 |
psTreeNode->panShapeIds[psTreeNode->nShapeCount-1] = psObject->nShapeId; |
| 504 |
|
| 505 |
if( psTreeNode->papsShapeObj != NULL ) |
| 506 |
{ |
| 507 |
psTreeNode->papsShapeObj = |
| 508 |
SfRealloc( psTreeNode->papsShapeObj, |
| 509 |
sizeof(void *) * psTreeNode->nShapeCount ); |
| 510 |
psTreeNode->papsShapeObj[psTreeNode->nShapeCount-1] = NULL; |
| 511 |
} |
| 512 |
|
| 513 |
return TRUE; |
| 514 |
} |
| 515 |
|
| 516 |
/************************************************************************/ |
| 517 |
/* SHPTreeAddShapeId() */ |
| 518 |
/* */ |
| 519 |
/* Add a shape to the tree, but don't keep a pointer to the */ |
| 520 |
/* object data, just keep the shapeid. */ |
| 521 |
/************************************************************************/ |
| 522 |
|
| 523 |
int SHPAPI_CALL |
| 524 |
SHPTreeAddShapeId( SHPTree * psTree, SHPObject * psObject ) |
| 525 |
|
| 526 |
{ |
| 527 |
return( SHPTreeNodeAddShapeId( psTree->psRoot, psObject, |
| 528 |
psTree->nMaxDepth, psTree->nDimension ) ); |
| 529 |
} |
| 530 |
|
| 531 |
/************************************************************************/ |
| 532 |
/* SHPTreeCollectShapesIds() */ |
| 533 |
/* */ |
| 534 |
/* Work function implementing SHPTreeFindLikelyShapes() on a */ |
| 535 |
/* tree node by tree node basis. */ |
| 536 |
/************************************************************************/ |
| 537 |
|
| 538 |
void SHPAPI_CALL |
| 539 |
SHPTreeCollectShapeIds( SHPTree *hTree, SHPTreeNode * psTreeNode, |
| 540 |
double * padfBoundsMin, double * padfBoundsMax, |
| 541 |
int * pnShapeCount, int * pnMaxShapes, |
| 542 |
int ** ppanShapeList ) |
| 543 |
|
| 544 |
{ |
| 545 |
int i; |
| 546 |
|
| 547 |
/* -------------------------------------------------------------------- */ |
| 548 |
/* Does this node overlap the area of interest at all? If not, */ |
| 549 |
/* return without adding to the list at all. */ |
| 550 |
/* -------------------------------------------------------------------- */ |
| 551 |
if( !SHPCheckBoundsOverlap( psTreeNode->adfBoundsMin, |
| 552 |
psTreeNode->adfBoundsMax, |
| 553 |
padfBoundsMin, |
| 554 |
padfBoundsMax, |
| 555 |
hTree->nDimension ) ) |
| 556 |
return; |
| 557 |
|
| 558 |
/* -------------------------------------------------------------------- */ |
| 559 |
/* Grow the list to hold the shapes on this node. */ |
| 560 |
/* -------------------------------------------------------------------- */ |
| 561 |
if( *pnShapeCount + psTreeNode->nShapeCount > *pnMaxShapes ) |
| 562 |
{ |
| 563 |
*pnMaxShapes = (*pnShapeCount + psTreeNode->nShapeCount) * 2 + 20; |
| 564 |
*ppanShapeList = (int *) |
| 565 |
SfRealloc(*ppanShapeList,sizeof(int) * *pnMaxShapes); |
| 566 |
} |
| 567 |
|
| 568 |
/* -------------------------------------------------------------------- */ |
| 569 |
/* Add the local nodes shapeids to the list. */ |
| 570 |
/* -------------------------------------------------------------------- */ |
| 571 |
for( i = 0; i < psTreeNode->nShapeCount; i++ ) |
| 572 |
{ |
| 573 |
(*ppanShapeList)[(*pnShapeCount)++] = psTreeNode->panShapeIds[i]; |
| 574 |
} |
| 575 |
|
| 576 |
/* -------------------------------------------------------------------- */ |
| 577 |
/* Recurse to subnodes if they exist. */ |
| 578 |
/* -------------------------------------------------------------------- */ |
| 579 |
for( i = 0; i < psTreeNode->nSubNodes; i++ ) |
| 580 |
{ |
| 581 |
if( psTreeNode->apsSubNode[i] != NULL ) |
| 582 |
SHPTreeCollectShapeIds( hTree, psTreeNode->apsSubNode[i], |
| 583 |
padfBoundsMin, padfBoundsMax, |
| 584 |
pnShapeCount, pnMaxShapes, |
| 585 |
ppanShapeList ); |
| 586 |
} |
| 587 |
} |
| 588 |
|
| 589 |
/************************************************************************/ |
| 590 |
/* SHPTreeFindLikelyShapes() */ |
| 591 |
/* */ |
| 592 |
/* Find all shapes within tree nodes for which the tree node */ |
| 593 |
/* bounding box overlaps the search box. The return value is */ |
| 594 |
/* an array of shapeids terminated by a -1. The shapeids will */ |
| 595 |
/* be in order, as hopefully this will result in faster (more */ |
| 596 |
/* sequential) reading from the file. */ |
| 597 |
/************************************************************************/ |
| 598 |
|
| 599 |
/* helper for qsort */ |
| 600 |
static int |
| 601 |
compare_ints( const void * a, const void * b) |
| 602 |
{ |
| 603 |
return (*(int*)a) - (*(int*)b); |
| 604 |
} |
| 605 |
|
| 606 |
int SHPAPI_CALL1(*) |
| 607 |
SHPTreeFindLikelyShapes( SHPTree * hTree, |
| 608 |
double * padfBoundsMin, double * padfBoundsMax, |
| 609 |
int * pnShapeCount ) |
| 610 |
|
| 611 |
{ |
| 612 |
int *panShapeList=NULL, nMaxShapes = 0; |
| 613 |
|
| 614 |
/* -------------------------------------------------------------------- */ |
| 615 |
/* Perform the search by recursive descent. */ |
| 616 |
/* -------------------------------------------------------------------- */ |
| 617 |
*pnShapeCount = 0; |
| 618 |
|
| 619 |
SHPTreeCollectShapeIds( hTree, hTree->psRoot, |
| 620 |
padfBoundsMin, padfBoundsMax, |
| 621 |
pnShapeCount, &nMaxShapes, |
| 622 |
&panShapeList ); |
| 623 |
|
| 624 |
/* -------------------------------------------------------------------- */ |
| 625 |
/* Sort the id array */ |
| 626 |
/* -------------------------------------------------------------------- */ |
| 627 |
|
| 628 |
qsort(panShapeList, *pnShapeCount, sizeof(int), compare_ints); |
| 629 |
|
| 630 |
return panShapeList; |
| 631 |
} |
| 632 |
|
| 633 |
/************************************************************************/ |
| 634 |
/* SHPTreeNodeTrim() */ |
| 635 |
/* */ |
| 636 |
/* This is the recurve version of SHPTreeTrimExtraNodes() that */ |
| 637 |
/* walks the tree cleaning it up. */ |
| 638 |
/************************************************************************/ |
| 639 |
|
| 640 |
static int SHPTreeNodeTrim( SHPTreeNode * psTreeNode ) |
| 641 |
|
| 642 |
{ |
| 643 |
int i; |
| 644 |
|
| 645 |
/* -------------------------------------------------------------------- */ |
| 646 |
/* Trim subtrees, and free subnodes that come back empty. */ |
| 647 |
/* -------------------------------------------------------------------- */ |
| 648 |
for( i = 0; i < psTreeNode->nSubNodes; i++ ) |
| 649 |
{ |
| 650 |
if( SHPTreeNodeTrim( psTreeNode->apsSubNode[i] ) ) |
| 651 |
{ |
| 652 |
SHPDestroyTreeNode( psTreeNode->apsSubNode[i] ); |
| 653 |
|
| 654 |
psTreeNode->apsSubNode[i] = |
| 655 |
psTreeNode->apsSubNode[psTreeNode->nSubNodes-1]; |
| 656 |
|
| 657 |
psTreeNode->nSubNodes--; |
| 658 |
|
| 659 |
i--; /* process the new occupant of this subnode entry */ |
| 660 |
} |
| 661 |
} |
| 662 |
|
| 663 |
/* -------------------------------------------------------------------- */ |
| 664 |
/* We should be trimmed if we have no subnodes, and no shapes. */ |
| 665 |
/* -------------------------------------------------------------------- */ |
| 666 |
return( psTreeNode->nSubNodes == 0 && psTreeNode->nShapeCount == 0 ); |
| 667 |
} |
| 668 |
|
| 669 |
/************************************************************************/ |
| 670 |
/* SHPTreeTrimExtraNodes() */ |
| 671 |
/* */ |
| 672 |
/* Trim empty nodes from the tree. Note that we never trim an */ |
| 673 |
/* empty root node. */ |
| 674 |
/************************************************************************/ |
| 675 |
|
| 676 |
void SHPAPI_CALL |
| 677 |
SHPTreeTrimExtraNodes( SHPTree * hTree ) |
| 678 |
|
| 679 |
{ |
| 680 |
SHPTreeNodeTrim( hTree->psRoot ); |
| 681 |
} |
| 682 |
|
Parent Directory
| 
Revision Log