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Overview
Comment: | Preliminary tests show geopoly_overlap() is working. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | geojson |
Files: | files | file ages | folders |
SHA3-256: |
77bb7b7d7278725e4e02935d485c3540 |
User & Date: | drh 2018-05-12 20:28:51.628 |
Context
2018-05-12
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21:09 | Add the geopoly_svg() SQL function. (check-in: 318ba5f0c5 user: drh tags: geojson) | |
20:28 | Preliminary tests show geopoly_overlap() is working. (check-in: 77bb7b7d72 user: drh tags: geojson) | |
16:05 | An initial attempt at an overlap function in the geopoly extension. (check-in: c857976efb user: drh tags: geojson) | |
Changes
Changes to ext/misc/geopoly.c.
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16 17 18 19 20 21 22 23 24 25 26 27 28 29 | #include "sqlite3ext.h" SQLITE_EXTENSION_INIT1 #include <assert.h> #include <string.h> #include <stdlib.h> #include <stdio.h> #define SQLITE_HAVE_GEOPLOY 1 #ifndef JSON_NULL /* The following stuff repeats things found in json1 */ /* ** Versions of isspace(), isalnum() and isdigit() to which it is safe ** to pass signed char values. */ #ifdef sqlite3Isdigit | > > > > > > > > | 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 | #include "sqlite3ext.h" SQLITE_EXTENSION_INIT1 #include <assert.h> #include <string.h> #include <stdlib.h> #include <stdio.h> #define SQLITE_HAVE_GEOPLOY 1 /* Enable -DGEOPOLY_ENABLE_DEBUG for debugging facilities */ #ifdef GEOPOLY_ENABLE_DEBUG static int geo_debug = 0; # define GEODEBUG(X) if(geo_debug)printf X #else # define GEODEBUG(X) #endif #ifndef JSON_NULL /* The following stuff repeats things found in json1 */ /* ** Versions of isspace(), isalnum() and isdigit() to which it is safe ** to pass signed char values. */ #ifdef sqlite3Isdigit |
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635 636 637 638 639 640 641 642 643 644 645 646 647 648 | static int geopolyOverlap(GeoPoly *p1, GeoPoly *p2){ int nVertex = p1->nVertex + p2->nVertex + 2; GeoOverlap *p; int nByte; GeoEvent *pThisEvent; double rX; int rc = 0; GeoSegment *pActive = 0; GeoSegment *pSeg; unsigned char aOverlap[4]; nByte = sizeof(GeoEvent)*nVertex*2 + sizeof(GeoSegment)*nVertex + sizeof(GeoOverlap); | > | 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 | static int geopolyOverlap(GeoPoly *p1, GeoPoly *p2){ int nVertex = p1->nVertex + p2->nVertex + 2; GeoOverlap *p; int nByte; GeoEvent *pThisEvent; double rX; int rc = 0; int needSort = 0; GeoSegment *pActive = 0; GeoSegment *pSeg; unsigned char aOverlap[4]; nByte = sizeof(GeoEvent)*nVertex*2 + sizeof(GeoSegment)*nVertex + sizeof(GeoOverlap); |
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656 657 658 659 660 661 662 | pThisEvent = geopolySortEventsByX(p->aEvent, p->nEvent); rX = pThisEvent->x==0.0 ? -1.0 : 0.0; memset(aOverlap, 0, sizeof(aOverlap)); while( pThisEvent ){ if( pThisEvent->x!=rX ){ GeoSegment *pPrev = 0; int iMask = 0; | | > > > > > > > > > > > > > > | | | | | | > | 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 | pThisEvent = geopolySortEventsByX(p->aEvent, p->nEvent); rX = pThisEvent->x==0.0 ? -1.0 : 0.0; memset(aOverlap, 0, sizeof(aOverlap)); while( pThisEvent ){ if( pThisEvent->x!=rX ){ GeoSegment *pPrev = 0; int iMask = 0; GEODEBUG(("Distinct X: %g\n", pThisEvent->x)); rX = pThisEvent->x; if( needSort ){ pActive = geopolySortSegmentsByYAndC(pActive); needSort = 0; } for(pSeg=pActive; pSeg; pSeg=pSeg->pNext){ if( pPrev ){ if( pPrev->y!=pSeg->y ){ GEODEBUG(("MASK: %d\n", iMask)); aOverlap[iMask] = 1; } } iMask ^= pSeg->side; pPrev = pSeg; } pPrev = 0; for(pSeg=pActive; pSeg; pSeg=pSeg->pNext){ double y = pSeg->C*rX + pSeg->B; GEODEBUG(("Segment %d.%d %g->%g\n", pSeg->side, pSeg->idx, pSeg->y, y)); pSeg->y = y; if( pPrev ){ if( pPrev->y>pSeg->y ){ rc = 1; GEODEBUG(("Crossing: %d.%d and %d.%d\n", pPrev->side, pPrev->idx, pSeg->side, pSeg->idx)); goto geopolyOverlapDone; }else if( pPrev->y!=pSeg->y ){ GEODEBUG(("MASK: %d\n", iMask)); aOverlap[iMask] = 1; } } iMask ^= pSeg->side; pPrev = pSeg; } } GEODEBUG(("%s %d.%d C=%g B=%g\n", pThisEvent->eType ? "RM " : "ADD", pThisEvent->pSeg->side, pThisEvent->pSeg->idx, pThisEvent->pSeg->C, pThisEvent->pSeg->B)); if( pThisEvent->eType==0 ){ /* Add a segment */ pSeg = pThisEvent->pSeg; pSeg->y = pSeg->C*rX + pSeg->B; pSeg->pNext = pActive; pActive = pSeg; needSort = 1; }else{ /* Remove a segment */ if( pActive==pThisEvent->pSeg ){ pActive = pActive->pNext; }else{ for(pSeg=pActive; pSeg; pSeg=pSeg->pNext){ if( pSeg->pNext==pThisEvent->pSeg ){ |
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753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 | sqlite3_result_int(context, x); } } sqlite3_free(p1); sqlite3_free(p2); } #ifdef _WIN32 __declspec(dllexport) #endif int sqlite3_geopoly_init( sqlite3 *db, char **pzErrMsg, const sqlite3_api_routines *pApi ){ int rc = SQLITE_OK; static const struct { void (*xFunc)(sqlite3_context*,int,sqlite3_value**); int nArg; const char *zName; } aFunc[] = { { geopolyAreaFunc, 1, "geopoly_area" }, { geopolyBlobFunc, 1, "geopoly_blob" }, { geopolyJsonFunc, 1, "geopoly_json" }, { geopolyWithinFunc, 3, "geopoly_within" }, { geopolyOverlapFunc, 2, "geopoly_overlap" }, }; int i; SQLITE_EXTENSION_INIT2(pApi); (void)pzErrMsg; /* Unused parameter */ for(i=0; i<sizeof(aFunc)/sizeof(aFunc[0]) && rc==SQLITE_OK; i++){ rc = sqlite3_create_function(db, aFunc[i].zName, aFunc[i].nArg, SQLITE_UTF8, 0, aFunc[i].xFunc, 0, 0); } return rc; } | > > > > > > > > > > > > > | 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 | sqlite3_result_int(context, x); } } sqlite3_free(p1); sqlite3_free(p2); } /* ** Enable or disable debugging output */ static void geopolyDebugFunc( sqlite3_context *context, int argc, sqlite3_value **argv ){ #ifdef GEOPOLY_ENABLE_DEBUG geo_debug = sqlite3_value_int(argv[0]); #endif } #ifdef _WIN32 __declspec(dllexport) #endif int sqlite3_geopoly_init( sqlite3 *db, char **pzErrMsg, const sqlite3_api_routines *pApi ){ int rc = SQLITE_OK; static const struct { void (*xFunc)(sqlite3_context*,int,sqlite3_value**); int nArg; const char *zName; } aFunc[] = { { geopolyAreaFunc, 1, "geopoly_area" }, { geopolyBlobFunc, 1, "geopoly_blob" }, { geopolyJsonFunc, 1, "geopoly_json" }, { geopolyWithinFunc, 3, "geopoly_within" }, { geopolyOverlapFunc, 2, "geopoly_overlap" }, { geopolyDebugFunc, 1, "geopoly_debug" }, }; int i; SQLITE_EXTENSION_INIT2(pApi); (void)pzErrMsg; /* Unused parameter */ for(i=0; i<sizeof(aFunc)/sizeof(aFunc[0]) && rc==SQLITE_OK; i++){ rc = sqlite3_create_function(db, aFunc[i].zName, aFunc[i].nArg, SQLITE_UTF8, 0, aFunc[i].xFunc, 0, 0); } return rc; } |