PostGIS 3.7.0dev-r@@SVN_REVISION@@
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◆ RASTER_getPixelPolygons()

Datum RASTER_getPixelPolygons ( PG_FUNCTION_ARGS  )

Definition at line 355 of file rtpg_geometry.c.

356{
357 FuncCallContext *funcctx;
358 TupleDesc tupdesc;
359 rt_pixel pix = NULL;
360 rt_pixel pix2;
361 int call_cntr;
362 int max_calls;
363 int i = 0;
364
365 /* stuff done only on the first call of the function */
366 if (SRF_IS_FIRSTCALL()) {
367 MemoryContext oldcontext;
368 rt_pgraster *pgraster = NULL;
369 rt_raster raster = NULL;
370 rt_band band = NULL;
371 int nband = 1;
372 int numbands;
373 bool hasband = TRUE;
374 bool exclude_nodata_value = TRUE;
375 bool nocolumnx = FALSE;
376 bool norowy = FALSE;
377 int x = 0;
378 int y = 0;
379 int bounds[4] = {0};
380 int pixcount = 0;
381 double value = 0;
382 int isnodata = 0;
383
384 LWPOLY *poly;
385
386 POSTGIS_RT_DEBUG(3, "RASTER_getPixelPolygons first call");
387
388 /* create a function context for cross-call persistence */
389 funcctx = SRF_FIRSTCALL_INIT();
390
391 /* switch to memory context appropriate for multiple function calls */
392 oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
393
394 if (PG_ARGISNULL(0)) {
395 MemoryContextSwitchTo(oldcontext);
396 SRF_RETURN_DONE(funcctx);
397 }
398 pgraster = (rt_pgraster *) PG_DETOAST_DATUM(PG_GETARG_DATUM(0));
399
400 /* band */
401 if (PG_ARGISNULL(1))
402 hasband = FALSE;
403 else {
404 nband = PG_GETARG_INT32(1);
405 hasband = TRUE;
406 }
407
408 /* column */
409 if (PG_ARGISNULL(2))
410 nocolumnx = TRUE;
411 else {
412 bounds[0] = PG_GETARG_INT32(2);
413 bounds[1] = bounds[0];
414 }
415
416 /* row */
417 if (PG_ARGISNULL(3))
418 norowy = TRUE;
419 else {
420 bounds[2] = PG_GETARG_INT32(3);
421 bounds[3] = bounds[2];
422 }
423
424 /* exclude NODATA */
425 if (!PG_ARGISNULL(4))
426 exclude_nodata_value = PG_GETARG_BOOL(4);
427
428 raster = rt_raster_deserialize(pgraster, FALSE);
429 if (!raster) {
430 PG_FREE_IF_COPY(pgraster, 0);
431 ereport(ERROR, (
432 errcode(ERRCODE_OUT_OF_MEMORY),
433 errmsg("Could not deserialize raster")
434 ));
435 MemoryContextSwitchTo(oldcontext);
436 SRF_RETURN_DONE(funcctx);
437 }
438
439 /* raster empty, return empty set */
440 if (rt_raster_is_empty(raster)) {
441 elog(NOTICE, "Raster is empty. Returning empty set");
442 rt_raster_destroy(raster);
443 PG_FREE_IF_COPY(pgraster, 0);
444 MemoryContextSwitchTo(oldcontext);
445 SRF_RETURN_DONE(funcctx);
446 }
447
448 /* band specified, load band and info */
449 if (hasband) {
450 numbands = rt_raster_get_num_bands(raster);
451 POSTGIS_RT_DEBUGF(3, "band %d", nband);
452 POSTGIS_RT_DEBUGF(3, "# of bands %d", numbands);
453
454 if (nband < 1 || nband > numbands) {
455 elog(NOTICE, "Invalid band index (must use 1-based). Returning empty set");
456 rt_raster_destroy(raster);
457 PG_FREE_IF_COPY(pgraster, 0);
458 MemoryContextSwitchTo(oldcontext);
459 SRF_RETURN_DONE(funcctx);
460 }
461
462 band = rt_raster_get_band(raster, nband - 1);
463 if (!band) {
464 elog(NOTICE, "Could not find band at index %d. Returning empty set", nband);
465 rt_raster_destroy(raster);
466 PG_FREE_IF_COPY(pgraster, 0);
467 MemoryContextSwitchTo(oldcontext);
468 SRF_RETURN_DONE(funcctx);
469 }
470
471 if (!rt_band_get_hasnodata_flag(band))
472 exclude_nodata_value = FALSE;
473 }
474
475 /* set bounds if columnx, rowy not set */
476 if (nocolumnx) {
477 bounds[0] = 1;
478 bounds[1] = rt_raster_get_width(raster);
479 }
480 if (norowy) {
481 bounds[2] = 1;
482 bounds[3] = rt_raster_get_height(raster);
483 }
484 POSTGIS_RT_DEBUGF(3, "bounds (min x, max x, min y, max y) = (%d, %d, %d, %d)",
485 bounds[0], bounds[1], bounds[2], bounds[3]);
486
487 /* rowy */
488 pixcount = 0;
489 for (y = bounds[2]; y <= bounds[3]; y++) {
490 /* columnx */
491 for (x = bounds[0]; x <= bounds[1]; x++) {
492
493 value = 0;
494 isnodata = TRUE;
495
496 if (hasband) {
497 if (rt_band_get_pixel(band, x - 1, y - 1, &value, &isnodata) != ES_NONE) {
498
499 for (i = 0; i < pixcount; i++)
500 lwgeom_free(pix[i].geom);
501 if (pixcount) pfree(pix);
502
503 rt_band_destroy(band);
504 rt_raster_destroy(raster);
505 PG_FREE_IF_COPY(pgraster, 0);
506
507 MemoryContextSwitchTo(oldcontext);
508 elog(ERROR, "RASTER_getPixelPolygons: Could not get pixel value");
509 SRF_RETURN_DONE(funcctx);
510 }
511
512 /* don't continue if pixel is NODATA and to exclude NODATA */
513 if (isnodata && exclude_nodata_value) {
514 POSTGIS_RT_DEBUG(5, "pixel value is NODATA and exclude_nodata_value = TRUE");
515 continue;
516 }
517 }
518
519 /* geometry */
520 poly = rt_raster_pixel_as_polygon(raster, x - 1, y - 1);
521 if (!poly) {
522 for (i = 0; i < pixcount; i++)
523 lwgeom_free(pix[i].geom);
524 if (pixcount) pfree(pix);
525
526 if (hasband) rt_band_destroy(band);
527 rt_raster_destroy(raster);
528 PG_FREE_IF_COPY(pgraster, 0);
529
530 MemoryContextSwitchTo(oldcontext);
531 elog(ERROR, "RASTER_getPixelPolygons: Could not get pixel polygon");
532 SRF_RETURN_DONE(funcctx);
533 }
534
535 if (!pixcount)
536 pix = palloc(sizeof(struct rt_pixel_t) * (pixcount + 1));
537 else
538 pix = repalloc(pix, sizeof(struct rt_pixel_t) * (pixcount + 1));
539 if (pix == NULL) {
540
541 lwpoly_free(poly);
542 if (hasband) rt_band_destroy(band);
543 rt_raster_destroy(raster);
544 PG_FREE_IF_COPY(pgraster, 0);
545
546 MemoryContextSwitchTo(oldcontext);
547 elog(ERROR, "RASTER_getPixelPolygons: Could not allocate memory for storing pixel polygons");
548 SRF_RETURN_DONE(funcctx);
549 }
550 pix[pixcount].geom = (LWGEOM *) poly;
551 POSTGIS_RT_DEBUGF(5, "poly @ %p", poly);
552 POSTGIS_RT_DEBUGF(5, "geom @ %p", pix[pixcount].geom);
553
554 /* x, y */
555 pix[pixcount].x = x;
556 pix[pixcount].y = y;
557
558 /* value */
559 pix[pixcount].value = value;
560
561 /* NODATA */
562 if (hasband) {
563 if (exclude_nodata_value)
564 pix[pixcount].nodata = isnodata;
565 else
566 pix[pixcount].nodata = FALSE;
567 }
568 else {
569 pix[pixcount].nodata = isnodata;
570 }
571
572 pixcount++;
573 }
574 }
575
576 if (hasband) rt_band_destroy(band);
577 rt_raster_destroy(raster);
578 PG_FREE_IF_COPY(pgraster, 0);
579
580 /* shortcut if no pixcount */
581 if (pixcount < 1) {
582 elog(NOTICE, "No pixels found for band %d", nband);
583 MemoryContextSwitchTo(oldcontext);
584 SRF_RETURN_DONE(funcctx);
585 }
586
587 /* Store needed information */
588 funcctx->user_fctx = pix;
589
590 /* total number of tuples to be returned */
591 funcctx->max_calls = pixcount;
592 POSTGIS_RT_DEBUGF(3, "pixcount = %d", pixcount);
593
594 /* Build a tuple descriptor for our result type */
595 if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE) {
596 ereport(ERROR, (
597 errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
598 errmsg("function returning record called in context that cannot accept type record")
599 ));
600 }
601
602 BlessTupleDesc(tupdesc);
603 funcctx->tuple_desc = tupdesc;
604
605 MemoryContextSwitchTo(oldcontext);
606 }
607
608 /* stuff done on every call of the function */
609 funcctx = SRF_PERCALL_SETUP();
610
611 call_cntr = funcctx->call_cntr;
612 max_calls = funcctx->max_calls;
613 tupdesc = funcctx->tuple_desc;
614 pix2 = funcctx->user_fctx;
615
616 /* do when there is more left to send */
617 if (call_cntr < max_calls) {
618 Datum values[VALUES_LENGTH];
619 bool nulls[VALUES_LENGTH];
620 HeapTuple tuple;
621 Datum result;
622
623 GSERIALIZED *gser = NULL;
624 size_t gser_size = 0;
625
626 POSTGIS_RT_DEBUGF(3, "call number %d", call_cntr);
627
628 memset(nulls, FALSE, sizeof(bool) * VALUES_LENGTH);
629
630 /* convert LWGEOM to GSERIALIZED */
631 gser = gserialized_from_lwgeom(pix2[call_cntr].geom, &gser_size);
632 lwgeom_free(pix2[call_cntr].geom);
633
634 values[0] = PointerGetDatum(gser);
635 if (pix2[call_cntr].nodata)
636 nulls[1] = TRUE;
637 else
638 values[1] = Float8GetDatum(pix2[call_cntr].value);
639 values[2] = Int32GetDatum(pix2[call_cntr].x);
640 values[3] = Int32GetDatum(pix2[call_cntr].y);
641
642 /* build a tuple */
643 tuple = heap_form_tuple(tupdesc, values, nulls);
644
645 /* make the tuple into a datum */
646 result = HeapTupleGetDatum(tuple);
647
648 SRF_RETURN_NEXT(funcctx, result);
649 }
650 /* do when there is no more left */
651 else {
652 pfree(pix2);
653 SRF_RETURN_DONE(funcctx);
654 }
655}
result
char result[OUT_DOUBLE_BUFFER_SIZE]
Definition cu_print.c:267
TRUE
#define TRUE
Definition dbfopen.c:73
FALSE
#define FALSE
Definition dbfopen.c:72
gserialized_from_lwgeom
GSERIALIZED * gserialized_from_lwgeom(LWGEOM *geom, size_t *size)
Allocate a new GSERIALIZED from an LWGEOM.
Definition gserialized.c:251
lwgeom_free
void lwgeom_free(LWGEOM *geom)
Definition lwgeom.c:1246
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:608
rt_band_get_hasnodata_flag
int rt_band_get_hasnodata_flag(rt_band band)
Get hasnodata flag value.
Definition rt_band.c:833
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:1551
rt_raster_destroy
void rt_raster_destroy(rt_raster raster)
Release memory associated to a raster.
Definition rt_raster.c:86
ES_NONE
@ ES_NONE
Definition librtcore.h:182
rt_band_destroy
void rt_band_destroy(rt_band band)
Destroy a raster band.
Definition rt_band.c:499
rt_raster_get_num_bands
uint16_t rt_raster_get_num_bands(rt_raster raster)
Definition rt_raster.c:376
rt_raster_get_height
uint16_t rt_raster_get_height(rt_raster raster)
Definition rt_raster.c:133
rt_raster_get_width
uint16_t rt_raster_get_width(rt_raster raster)
Definition rt_raster.c:125
rt_raster_deserialize
rt_raster rt_raster_deserialize(void *serialized, int header_only)
Return a raster from a serialized form.
Definition rt_serialize.c:732
rt_raster_is_empty
int rt_raster_is_empty(rt_raster raster)
Return TRUE if the raster is empty.
Definition rt_raster.c:1240
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:385
genraster.value
int value
Definition genraster.py:62
pixval.nband
nband
Definition pixval.py:56
rtrowdump.raster
raster
Be careful!! Zeros function's input parameter can be a (height x width) array, not (width x height): ...
Definition rtrowdump.py:125
VALUES_LENGTH
#define VALUES_LENGTH
Definition rtpg_geometry.c:191
POSTGIS_RT_DEBUG
#define POSTGIS_RT_DEBUG(level, msg)
Definition rtpostgis.h:65
POSTGIS_RT_DEBUGF
#define POSTGIS_RT_DEBUGF(level, msg,...)
Definition rtpostgis.h:69
rt_band_t
Definition librtcore.h:2515
rt_pixel_t::y
int y
Definition librtcore.h:2537
rt_pixel_t::geom
LWGEOM * geom
Definition librtcore.h:2542
rt_pixel_t::value
double value
Definition librtcore.h:2540
rt_pixel_t::nodata
uint8_t nodata
Definition librtcore.h:2539
rt_pixel_t::x
int x
Definition librtcore.h:2536
rt_pixel_t
Definition librtcore.h:2535
rt_raster_serialized_t
Struct definitions.
Definition librtcore.h:2452
rt_raster_t
Definition librtcore.h:2486

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, result, 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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