Fix for incorrect scale/translate in ST_AsMVTGeom

git-svn-id: http://svn.osgeo.org/postgis/trunk@15326 b70326c6-7e19-0410-871a-916f4a2858ee

diff --git a/postgis/mvt.c b/postgis/mvt.c
index ee19248bef78fb027445df24e5b378b5e5948b22..e38a39cec38d0563dc5a1c45314ecfc78a19b692 100644 (file)
--- a/postgis/mvt.c
+++ b/postgis/mvt.c
@@ -444,55 +444,6 @@ static void parse_values(struct mvt_agg_context *ctx)
        ctx->feature->tags = tags;
 }
 
-static void ptarray_mirror_y(POINTARRAY *pa, uint32_t extent)
-{
-       int i;
-       POINT2D *p;
-
-       for (i = 0; i < pa->npoints; i++) {
-               p = (POINT2D *) getPoint_internal(pa, i);
-               p->y = extent - p->y;
-       }
-}
-
-static void lwgeom_mirror_y(LWGEOM *in, uint32_t extent)
-{
-       LWCOLLECTION *col;
-       LWPOLY *poly;
-       int i;
-
-       if ( (!in) || lwgeom_is_empty(in) ) return;
-
-       switch (in->type) {
-       case POINTTYPE:
-               ptarray_mirror_y(lwgeom_as_lwpoint(in)->point, extent);
-               break;
-       case LINETYPE:
-               ptarray_mirror_y(lwgeom_as_lwline(in)->points, extent);
-               break;
-       case POLYGONTYPE:
-               poly = (LWPOLY *) in;
-               for (i=0; i<poly->nrings; i++)
-                       ptarray_mirror_y(poly->rings[i], extent);
-               break;
-       case MULTIPOINTTYPE:
-       case MULTILINETYPE:
-       case MULTIPOLYGONTYPE:
-       case COLLECTIONTYPE:
-               col = (LWCOLLECTION *) in;
-               for (i=0; i<col->ngeoms; i++)
-                       lwgeom_mirror_y(col->geoms[i], extent);
-               break;
-       default:
-               lwerror("lwgeom_mirror_y: unsupported geometry type: %s",
-                       lwtype_name(in->type));
-               return;
-       }
-
-       lwgeom_drop_bbox(in);
-       lwgeom_add_bbox(in);
-}
-
 /**
  * Transform a geometry into vector tile coordinate space.
  *
@@ -506,6 +457,8 @@ LWGEOM *mvt_geom(LWGEOM *lwgeom, GBOX *gbox, uint32_t extent, uint32_t buffer,
        double height = gbox->ymax - gbox->ymin;
        double resx = width / extent;
        double resy = height / extent;
+       double fx = extent / width;
+       double fy = -(extent / height);
 
        if (width == 0 || height == 0)
                lwerror("mvt_geom: bounds width or height cannot be 0");
@@ -529,13 +482,15 @@ LWGEOM *mvt_geom(LWGEOM *lwgeom, GBOX *gbox, uint32_t extent, uint32_t buffer,
 #endif
        }
 
-       POINT4D factors;
-       factors.x = resx;
-       factors.y = resy;
-       factors.z = 1;
-       factors.m = 1;
+       AFFINE affine;
+       memset (&affine, 0, sizeof(affine));
+       affine.afac = fx;
+       affine.efac = fy;
+       affine.ifac = 1;
+       affine.xoff = -gbox->xmin * fx;
+       affine.yoff = -gbox->ymax * fy;
 
-       lwgeom_scale(lwgeom, &factors);
+       lwgeom_affine(lwgeom, &affine);
 
        gridspec grid;
        memset(&grid, 0, sizeof(gridspec));
@@ -550,7 +505,6 @@ LWGEOM *mvt_geom(LWGEOM *lwgeom, GBOX *gbox, uint32_t extent, uint32_t buffer,
                lwgeom_out = lwgeom_grid(lwgeom_centroid(lwgeom), &grid);
 
        lwgeom_force_clockwise(lwgeom_out);
-       lwgeom_mirror_y(lwgeom_out, extent);
        lwgeom_out = lwgeom_make_valid(lwgeom_out);
 
        return lwgeom_out;

diff --git a/regress/mvt.sql b/regress/mvt.sql
index ffa22c800544a99afdfaa5f2e28495fc0abba994..f5a5fca3473b52a8fded1a52d9658e2420551f3e 100644 (file)
--- a/regress/mvt.sql
+++ b/regress/mvt.sql
@@ -17,7 +17,11 @@ select 'PG4', ST_AsText(ST_AsMVTGeom(
        4096, 0, false));
 select 'PG5', ST_AsText(ST_AsMVTGeom(
        ST_GeomFromText('POLYGON ((0 0, 10 0, 10 5, 0 -5, 0 0))'),
-       ST_MakeBox2D(ST_Point(0, 0), ST_Point(1, 1)),
+       ST_MakeBox2D(ST_Point(0, 0), ST_Point(4096*4096, 4096*4096)),
+       4096, 0, false));
+select 'PG6', ST_AsText(ST_AsMVTGeom(
+       ST_GeomFromText('POLYGON ((762780 6474467, 717821 6797045, 1052826 6797045, 762780 6474467))'),
+       ST_MakeBox2D(ST_Point(626172.135625, 6261721.35625), ST_Point(1252344.27125, 6887893.49188)),
        4096, 0, false));
 
 -- geometry encoding tests

diff --git a/regress/mvt_expected b/regress/mvt_expected
index 2239f862956df28dfc0ba90fd87c8c731421121b..97e843d9e1bc633f005123a74c309036717d2181 100644 (file)
--- a/regress/mvt_expected
+++ b/regress/mvt_expected
@@ -1,16 +1,17 @@
 PG1|POINT(1 4094)
-PG2|POINT(2 4092)
-PG3|POINT(0 4095)
+PG2|POINT(0 4095)
+PG3|POINT(2 4092)
 PG4|MULTIPOLYGON(((5 4096,10 4096,10 4091,5 4096)),((0 4096,0 4101,5 4096,0 4096)))
 PG5|POINT(0 4096)
+PG6|POLYGON((894 2704,2791 594,600 594,894 2704))
 TG1|GiEKBHRlc3QSDBICAAAYASIECTLePxoCYzEiAigBKIAgeAI=
 TG2|GiMKBHRlc3QSDhICAAAYASIGETLePwIBGgJjMSICKAEogCB4Ag==
 TG3|GiYKBHRlc3QSERICAAAYAiIJCQCAQArQD88PGgJjMSICKAEogCB4Ag==
 TG4|GioKBHRlc3QSFRICAAAYAiINCQCAQBLoB+cH6AfnBxoCYzEiAigBKIAgeAI=
 TG5|GjgKBHRlc3QSIxICAAAYAiIbCQL+PxLoB+cH6AfnBwnND84PEugH5wfoB+cHGgJjMSICKAEogCB4
 Ag==
-TG6|GjIKBHRlc3QSHRICAAAYAyIVCUbsPxoxEwonPAkPCTEeEhQUCh0PGgJjMSICKAEogCB4Ag==
-TG7|Gj0KBHRlc3QSKBICAAAYAyIgCVCwPxIKFDEdDwkAFCIyHh0eJwkAJw8JKBQSEwkAFA8aAmMxIgIo
+TG6|GjIKBHRlc3QSHRICAAAYAyIVCUbsPxoURTsKCSgPCRQTEh4JCR4PGgJjMSICKAEogCB4Ag==
+TG7|Gj0KBHRlc3QSKBICAAAYAyIgCVCwPxInCTIeDwkxCSITCgAoKAoeHQ8JHQASEwoAEw8aAmMxIgIo
 ASiAIHgC
 TG8|GiEKBHRlc3QSDBICAAAYASIECTLePxoCYzEiAigBKIAgeAI=
 TG9|GiMKBHRlc3QSDhICAAAYASIGETLeP2VGGgJjMSICKAEogCB4Ag==