PostGIS 3.0.6dev-r@@SVN_REVISION@@
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◆ RASTER_getPixelPolygons()

Datum RASTER_getPixelPolygons ( PG_FUNCTION_ARGS  )

Definition at line 352 of file rtpg_geometry.c.

353{
354 FuncCallContext *funcctx;
355 TupleDesc tupdesc;
356 rt_pixel pix = NULL;
357 rt_pixel pix2;
358 int call_cntr;
359 int max_calls;
360 int i = 0;
361
362 /* stuff done only on the first call of the function */
363 if (SRF_IS_FIRSTCALL()) {
364 MemoryContext oldcontext;
365 rt_pgraster *pgraster = NULL;
366 rt_raster raster = NULL;
367 rt_band band = NULL;
368 int nband = 1;
369 int numbands;
370 bool hasband = TRUE;
371 bool exclude_nodata_value = TRUE;
372 bool nocolumnx = FALSE;
373 bool norowy = FALSE;
374 int x = 0;
375 int y = 0;
376 int bounds[4] = {0};
377 int pixcount = 0;
378 double value = 0;
379 int isnodata = 0;
380
381 LWPOLY *poly;
382
383 POSTGIS_RT_DEBUG(3, "RASTER_getPixelPolygons first call");
384
385 /* create a function context for cross-call persistence */
386 funcctx = SRF_FIRSTCALL_INIT();
387
388 /* switch to memory context appropriate for multiple function calls */
389 oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
390
391 if (PG_ARGISNULL(0)) {
392 MemoryContextSwitchTo(oldcontext);
393 SRF_RETURN_DONE(funcctx);
394 }
395 pgraster = (rt_pgraster *) PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
396
397 /* band */
398 if (PG_ARGISNULL(1))
399 hasband = FALSE;
400 else {
401 nband = PG_GETARG_INT32(1);
402 hasband = TRUE;
403 }
404
405 /* column */
406 if (PG_ARGISNULL(2))
407 nocolumnx = TRUE;
408 else {
409 bounds[0] = PG_GETARG_INT32(2);
410 bounds[1] = bounds[0];
411 }
412
413 /* row */
414 if (PG_ARGISNULL(3))
415 norowy = TRUE;
416 else {
417 bounds[2] = PG_GETARG_INT32(3);
418 bounds[3] = bounds[2];
419 }
420
421 /* exclude NODATA */
422 if (!PG_ARGISNULL(4))
423 exclude_nodata_value = PG_GETARG_BOOL(4);
424
425 raster = rt_raster_deserialize(pgraster, FALSE);
426 if (!raster) {
427 PG_FREE_IF_COPY(pgraster, 0);
428 ereport(ERROR, (
429 errcode(ERRCODE_OUT_OF_MEMORY),
430 errmsg("Could not deserialize raster")
431 ));
432 MemoryContextSwitchTo(oldcontext);
433 SRF_RETURN_DONE(funcctx);
434 }
435
436 /* raster empty, return NULL */
437 if (rt_raster_is_empty(raster)) {
438 elog(NOTICE, "Raster is empty. Returning NULL");
439 rt_raster_destroy(raster);
440 PG_FREE_IF_COPY(pgraster, 0);
441 MemoryContextSwitchTo(oldcontext);
442 SRF_RETURN_DONE(funcctx);
443 }
444
445 /* band specified, load band and info */
446 if (hasband) {
447 numbands = rt_raster_get_num_bands(raster);
448 POSTGIS_RT_DEBUGF(3, "band %d", nband);
449 POSTGIS_RT_DEBUGF(3, "# of bands %d", numbands);
450
451 if (nband < 1 || nband > numbands) {
452 elog(NOTICE, "Invalid band index (must use 1-based). Returning NULL");
453 rt_raster_destroy(raster);
454 PG_FREE_IF_COPY(pgraster, 0);
455 MemoryContextSwitchTo(oldcontext);
456 SRF_RETURN_DONE(funcctx);
457 }
458
459 band = rt_raster_get_band(raster, nband - 1);
460 if (!band) {
461 elog(NOTICE, "Could not find band at index %d. Returning NULL", nband);
462 rt_raster_destroy(raster);
463 PG_FREE_IF_COPY(pgraster, 0);
464 MemoryContextSwitchTo(oldcontext);
465 SRF_RETURN_DONE(funcctx);
466 }
467
468 if (!rt_band_get_hasnodata_flag(band))
469 exclude_nodata_value = FALSE;
470 }
471
472 /* set bounds if columnx, rowy not set */
473 if (nocolumnx) {
474 bounds[0] = 1;
475 bounds[1] = rt_raster_get_width(raster);
476 }
477 if (norowy) {
478 bounds[2] = 1;
479 bounds[3] = rt_raster_get_height(raster);
480 }
481 POSTGIS_RT_DEBUGF(3, "bounds (min x, max x, min y, max y) = (%d, %d, %d, %d)",
482 bounds[0], bounds[1], bounds[2], bounds[3]);
483
484 /* rowy */
485 pixcount = 0;
486 for (y = bounds[2]; y <= bounds[3]; y++) {
487 /* columnx */
488 for (x = bounds[0]; x <= bounds[1]; x++) {
489
490 value = 0;
491 isnodata = TRUE;
492
493 if (hasband) {
494 if (rt_band_get_pixel(band, x - 1, y - 1, &value, &isnodata) != ES_NONE) {
495
496 for (i = 0; i < pixcount; i++)
497 lwgeom_free(pix[i].geom);
498 if (pixcount) pfree(pix);
499
500 rt_band_destroy(band);
501 rt_raster_destroy(raster);
502 PG_FREE_IF_COPY(pgraster, 0);
503
504 MemoryContextSwitchTo(oldcontext);
505 elog(ERROR, "RASTER_getPixelPolygons: Could not get pixel value");
506 SRF_RETURN_DONE(funcctx);
507 }
508
509 /* don't continue if pixel is NODATA and to exclude NODATA */
510 if (isnodata && exclude_nodata_value) {
511 POSTGIS_RT_DEBUG(5, "pixel value is NODATA and exclude_nodata_value = TRUE");
512 continue;
513 }
514 }
515
516 /* geometry */
517 poly = rt_raster_pixel_as_polygon(raster, x - 1, y - 1);
518 if (!poly) {
519 for (i = 0; i < pixcount; i++)
520 lwgeom_free(pix[i].geom);
521 if (pixcount) pfree(pix);
522
523 if (hasband) rt_band_destroy(band);
524 rt_raster_destroy(raster);
525 PG_FREE_IF_COPY(pgraster, 0);
526
527 MemoryContextSwitchTo(oldcontext);
528 elog(ERROR, "RASTER_getPixelPolygons: Could not get pixel polygon");
529 SRF_RETURN_DONE(funcctx);
530 }
531
532 if (!pixcount)
533 pix = palloc(sizeof(struct rt_pixel_t) * (pixcount + 1));
534 else
535 pix = repalloc(pix, sizeof(struct rt_pixel_t) * (pixcount + 1));
536 if (pix == NULL) {
537
538 lwpoly_free(poly);
539 if (hasband) rt_band_destroy(band);
540 rt_raster_destroy(raster);
541 PG_FREE_IF_COPY(pgraster, 0);
542
543 MemoryContextSwitchTo(oldcontext);
544 elog(ERROR, "RASTER_getPixelPolygons: Could not allocate memory for storing pixel polygons");
545 SRF_RETURN_DONE(funcctx);
546 }
547 pix[pixcount].geom = (LWGEOM *) poly;
548 POSTGIS_RT_DEBUGF(5, "poly @ %p", poly);
549 POSTGIS_RT_DEBUGF(5, "geom @ %p", pix[pixcount].geom);
550
551 /* x, y */
552 pix[pixcount].x = x;
553 pix[pixcount].y = y;
554
555 /* value */
556 pix[pixcount].value = value;
557
558 /* NODATA */
559 if (hasband) {
560 if (exclude_nodata_value)
561 pix[pixcount].nodata = isnodata;
562 else
563 pix[pixcount].nodata = FALSE;
564 }
565 else {
566 pix[pixcount].nodata = isnodata;
567 }
568
569 pixcount++;
570 }
571 }
572
573 if (hasband) rt_band_destroy(band);
574 rt_raster_destroy(raster);
575 PG_FREE_IF_COPY(pgraster, 0);
576
577 /* shortcut if no pixcount */
578 if (pixcount < 1) {
579 elog(NOTICE, "No pixels found for band %d", nband);
580 MemoryContextSwitchTo(oldcontext);
581 SRF_RETURN_DONE(funcctx);
582 }
583
584 /* Store needed information */
585 funcctx->user_fctx = pix;
586
587 /* total number of tuples to be returned */
588 funcctx->max_calls = pixcount;
589 POSTGIS_RT_DEBUGF(3, "pixcount = %d", pixcount);
590
591 /* Build a tuple descriptor for our result type */
592 if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE) {
593 ereport(ERROR, (
594 errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
595 errmsg("function returning record called in context that cannot accept type record")
596 ));
597 }
598
599 BlessTupleDesc(tupdesc);
600 funcctx->tuple_desc = tupdesc;
601
602 MemoryContextSwitchTo(oldcontext);
603 }
604
605 /* stuff done on every call of the function */
606 funcctx = SRF_PERCALL_SETUP();
607
608 call_cntr = funcctx->call_cntr;
609 max_calls = funcctx->max_calls;
610 tupdesc = funcctx->tuple_desc;
611 pix2 = funcctx->user_fctx;
612
613 /* do when there is more left to send */
614 if (call_cntr < max_calls) {
615 Datum values[VALUES_LENGTH];
616 bool nulls[VALUES_LENGTH];
617 HeapTuple tuple;
618 Datum result;
619
620 GSERIALIZED *gser = NULL;
621 size_t gser_size = 0;
622
623 POSTGIS_RT_DEBUGF(3, "call number %d", call_cntr);
624
625 memset(nulls, FALSE, sizeof(bool) * VALUES_LENGTH);
626
627 /* convert LWGEOM to GSERIALIZED */
628 gser = gserialized_from_lwgeom(pix2[call_cntr].geom, &gser_size);
629 lwgeom_free(pix2[call_cntr].geom);
630
631 values[0] = PointerGetDatum(gser);
632 if (pix2[call_cntr].nodata)
633 nulls[1] = TRUE;
634 else
635 values[1] = Float8GetDatum(pix2[call_cntr].value);
636 values[2] = Int32GetDatum(pix2[call_cntr].x);
637 values[3] = Int32GetDatum(pix2[call_cntr].y);
638
639 /* build a tuple */
640 tuple = heap_form_tuple(tupdesc, values, nulls);
641
642 /* make the tuple into a datum */
643 result = HeapTupleGetDatum(tuple);
644
645 SRF_RETURN_NEXT(funcctx, result);
646 }
647 /* do when there is no more left */
648 else {
649 pfree(pix2);
650 SRF_RETURN_DONE(funcctx);
651 }
652}
TRUE
#define TRUE
Definition dbfopen.c:169
FALSE
#define FALSE
Definition dbfopen.c:168
gserialized_from_lwgeom
GSERIALIZED * gserialized_from_lwgeom(LWGEOM *geom, size_t *size)
Allocate a new GSERIALIZED from an LWGEOM.
Definition gserialized.c:222
lwgeom_free
void lwgeom_free(LWGEOM *geom)
Definition lwgeom.c:1138
lwpoly_free
void lwpoly_free(LWPOLY *poly)
Definition lwpoly.c:175
rt_raster_pixel_as_polygon
LWPOLY * rt_raster_pixel_as_polygon(rt_raster raster, int x, int y)
Get a raster pixel as a polygon.
Definition rt_geometry.c:610
rt_band_get_hasnodata_flag
int rt_band_get_hasnodata_flag(rt_band band)
Get hasnodata flag value.
Definition rt_band.c:674
rt_band_get_pixel
rt_errorstate rt_band_get_pixel(rt_band band, int x, int y, double *value, int *nodata)
Get pixel value.
Definition rt_band.c:1221
rt_raster_destroy
void rt_raster_destroy(rt_raster raster)
Release memory associated to a raster.
Definition rt_raster.c:82
ES_NONE
@ ES_NONE
Definition librtcore.h:180
rt_band_destroy
void rt_band_destroy(rt_band band)
Destroy a raster band.
Definition rt_band.c:340
rt_raster_get_num_bands
uint16_t rt_raster_get_num_bands(rt_raster raster)
Definition rt_raster.c:372
rt_raster_get_height
uint16_t rt_raster_get_height(rt_raster raster)
Definition rt_raster.c:129
rt_raster_get_width
uint16_t rt_raster_get_width(rt_raster raster)
Definition rt_raster.c:121
rt_raster_deserialize
rt_raster rt_raster_deserialize(void *serialized, int header_only)
Return a raster from a serialized form.
Definition rt_serialize.c:725
rt_raster_is_empty
int rt_raster_is_empty(rt_raster raster)
Return TRUE if the raster is empty.
Definition rt_raster.c:1329
rt_raster_get_band
rt_band rt_raster_get_band(rt_raster raster, int bandNum)
Return Nth band, or NULL if unavailable.
Definition rt_raster.c:381
genraster.value
int value
Definition genraster.py:62
pixval.nband
nband
Definition pixval.py:53
rtrowdump.raster
raster
Be careful!! Zeros function's input parameter can be a (height x width) array, not (width x height): ...
Definition rtrowdump.py:121
VALUES_LENGTH
#define VALUES_LENGTH
Definition rtpg_geometry.c:188
POSTGIS_RT_DEBUG
#define POSTGIS_RT_DEBUG(level, msg)
Definition rtpostgis.h:61
POSTGIS_RT_DEBUGF
#define POSTGIS_RT_DEBUGF(level, msg,...)
Definition rtpostgis.h:65
rt_band_t
Definition librtcore.h:2314
rt_pixel_t::y
int y
Definition librtcore.h:2336
rt_pixel_t::geom
LWGEOM * geom
Definition librtcore.h:2341
rt_pixel_t::value
double value
Definition librtcore.h:2339
rt_pixel_t::nodata
uint8_t nodata
Definition librtcore.h:2338
rt_pixel_t::x
int x
Definition librtcore.h:2335
rt_pixel_t
Definition librtcore.h:2334
rt_raster_serialized_t
Struct definitions.
Definition librtcore.h:2251
rt_raster_t
Definition librtcore.h:2285

References ES_NONE, FALSE, rt_pixel_t::geom, gserialized_from_lwgeom(), lwgeom_free(), lwpoly_free(), rt_pixel_t::nodata, POSTGIS_RT_DEBUG, POSTGIS_RT_DEBUGF, rt_band_destroy(), rt_band_get_hasnodata_flag(), rt_band_get_pixel(), rt_raster_deserialize(), rt_raster_destroy(), rt_raster_get_band(), rt_raster_get_height(), rt_raster_get_num_bands(), rt_raster_get_width(), rt_raster_is_empty(), rt_raster_pixel_as_polygon(), TRUE, rt_pixel_t::value, VALUES_LENGTH, rt_pixel_t::x, and rt_pixel_t::y.

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