return result;
}
+int
+lwgeom_empty_length(int SRID)
+{
+ int size = 5;
+ if ( SRID != 1 ) size += 4;
+ return size;
+}
+
+// construct the empty geometry (GEOMETRYCOLLECTION(EMPTY))
+// writing it into the provided buffer.
+void
+lwgeom_constructempty_buf(int SRID, int ndims, char *buf, int *retsize)
+{
+ int ngeoms = 0;
+
+ buf[0] =(unsigned char) lwgeom_makeType( ndims, SRID != -1, COLLECTIONTYPE);
+ if (SRID != -1)
+ {
+ memcpy(&buf[1],&SRID,4);
+ buf += 5;
+ }
+ else
+ buf += 1;
+
+ memcpy(buf, &ngeoms, 4);
+
+ *retsize = lwgeom_empty_length(SRID);
+}
+
// helper function (not for general use)
// find the size a geometry (or a sub-geometry)
// 1st geometry has geom_number = 0
result->SRID = -1;
result->ndims = 0;
pfree_inspected(inspected);
- elog(NOTICE, "lwgeom_explode: no geometries");
+ //elog(NOTICE, "lwgeom_explode: no geometries");
return result;
}
return expcoll;
}
-
/*
* Serialized a LWGEOM_EXPLODED structure
*/
char *
lwexploded_serialize(LWGEOM_EXPLODED *exploded, int wantbbox)
+{
+ int sizecom = 0;
+ int size = lwexploded_findlength(exploded, wantbbox);
+ char *result = palloc(size);
+ lwexploded_serialize_buf(exploded, wantbbox, result, &sizecom);
+ elog(NOTICE, "findlength:%d, serialize_buf:%d", size, sizecom);
+ return result;
+}
+
+/*
+ * Serialized a LWGEOM_EXPLODED structure into a
+ * pre-allocated memory space.
+ * Use lwexploded_findlength to know the required size
+ * of the provided buffer.
+ */
+void
+lwexploded_serialize_buf(LWGEOM_EXPLODED *exploded, int wantbbox,
+ char *buf, int *retsize)
{
unsigned int size=0;
int i;
int ntypes = 0;
int ngeoms = 0;
- char *result, *loc;
+ char *loc;
int outtype = 0;
LWPOLY *poly;
LWLINE *line;
LWPOINT *point;
BOX2DFLOAT4 *box2d;
BOX3D *box3d;
- char *ser;
-
- if ( exploded->npoints + exploded->nlines + exploded->npolys == 0 )
- {
- return lwgeom_constructempty(exploded->SRID, exploded->ndims);
- }
- // find size of all geoms.
- // If BBOX and SRID are included this size could be
- // larger then needed, but that should not be a problem
- for (i=0; i<exploded->npoints; i++)
- size += lwpoint_findlength(exploded->points[i]);
- for (i=0; i<exploded->nlines; i++)
- size += lwline_findlength(exploded->lines[i]);
- for (i=0; i<exploded->npolys; i++)
- size += lwpoly_findlength(exploded->polys[i]);
+ ngeoms = exploded->npoints + exploded->nlines + exploded->npolys;
- if ( exploded->npoints )
- {
- ntypes++;
- outtype = (exploded->npoints>1) ? MULTIPOINTTYPE : POINTTYPE;
- }
- if ( exploded->nlines )
- {
- ntypes++;
- if ( outtype ) outtype = COLLECTIONTYPE;
- else outtype = (exploded->nlines>1) ? MULTILINETYPE : LINETYPE;
- }
- if ( exploded->npolys )
+ if ( ngeoms == 0 )
{
- ntypes++;
- if ( outtype ) outtype = COLLECTIONTYPE;
- else outtype = (exploded->npolys>1) ? MULTIPOLYGONTYPE : POLYGONTYPE;
+ lwgeom_constructempty_buf(exploded->SRID, exploded->ndims,
+ buf, retsize);
+ return;
}
- ngeoms = exploded->npoints + exploded->nlines + exploded->npolys;
-
-#ifdef DEBUG
- elog(NOTICE, " computed outtype: %d, ngeoms: %d", outtype, ngeoms);
-#endif
// For a single geometry just set SRID and BBOX (if requested)
- if ( ngeoms < 2 )
+ if ( ngeoms == 1 )
{
- if ( exploded->npoints )
- {
+ loc = buf;
+
+ if ( exploded->npoints ) {
+
+ if ( wantbbox && !
+ lwgeom_hasBBOX(exploded->points[0][0]) )
+ {
+ loc += sizeof(BOX2DFLOAT4);
+ }
point = lwpoint_deserialize(exploded->points[0]);
point->SRID = exploded->SRID;
- ser = lwpoint_serialize(point);
+ lwpoint_serialize_buf(point, loc, &size);
pfree_point(point);
- size = lwpoint_findlength(ser);
}
- else if ( exploded->nlines )
- {
+ else if ( exploded->nlines ) {
+ if ( wantbbox && !
+ lwgeom_hasBBOX(exploded->lines[0][0]) )
+ {
+ loc += sizeof(BOX2DFLOAT4);
+ }
line = lwline_deserialize(exploded->lines[0]);
line->SRID = exploded->SRID;
- ser = lwline_serialize(line);
+ lwline_serialize_buf(line, loc, &size);
pfree_line(line);
- size = lwline_findlength(ser);
}
- else if ( exploded->npolys )
- {
+ else if ( exploded->npolys ) {
+ if ( wantbbox && !
+ lwgeom_hasBBOX(exploded->polys[0][0]) )
+ {
+ loc += sizeof(BOX2DFLOAT4);
+ }
poly = lwpoly_deserialize(exploded->polys[0]);
poly->SRID = exploded->SRID;
- ser = lwpoly_serialize(poly);
+ lwpoly_serialize_buf(poly, loc, &size);
pfree_polygon(poly);
- size = lwpoly_findlength(ser);
+
+ }
+ else {
+ *retsize = 0;
+ return; // ERROR !!
}
- else return NULL;
- if ( wantbbox && ! lwgeom_hasBBOX(ser[0]) )
+
+
+ // Now compute the bounding box and write it
+ if ( wantbbox && ! lwgeom_hasBBOX(loc[0]) )
{
- result = palloc(size+4);
- result[0] = TYPE_SETHASBBOX(ser[0], 1);
- loc = result+1;
- box3d = lw_geom_getBB_simple(ser);
+ buf[0] = TYPE_SETHASBBOX(loc[0], 1);
+ box3d = lw_geom_getBB_simple(loc);
box2d = box3d_to_box2df(box3d);
+ loc = buf+1;
memcpy(loc, box2d, sizeof(BOX2DFLOAT4));
- loc += sizeof(BOX2DFLOAT4);
- memcpy(loc, (ser+1), size-1);
- pfree(ser);
-#ifdef DEBUG_EXPLODED
-checkexplodedsize(result, exploded, size+4, wantbbox);
-#endif
- return result;
- }
- else
- {
-#ifdef DEBUG_EXPLODED
-checkexplodedsize(ser, exploded, -1, wantbbox);
-#endif
- return ser;
+ size += sizeof(BOX2DFLOAT4);
}
+
+ *retsize = size;
+ return;
}
- // Add size for 3 multigeoms + root geom + bbox and srid.
- // Also in this case we are considering worst case.
- size += 24+sizeof(BOX2DFLOAT4);
+ if ( exploded->npoints ) {
+ ntypes++;
+ outtype = (exploded->npoints>1) ? MULTIPOINTTYPE : POINTTYPE;
+ }
+ if ( exploded->nlines ) {
+ ntypes++;
+ if ( outtype ) outtype = COLLECTIONTYPE;
+ else outtype = (exploded->nlines>1) ? MULTILINETYPE : LINETYPE;
+ }
+ if ( exploded->npolys ) {
+ ntypes++;
+ if ( outtype ) outtype = COLLECTIONTYPE;
+ else outtype = (exploded->npolys>1) ? MULTIPOLYGONTYPE : POLYGONTYPE;
+ }
#ifdef DEBUG
- elog(NOTICE, " computed totsize: %d", size);
+ elog(NOTICE, " computed outtype: %d, ngeoms: %d", outtype, ngeoms);
#endif
- result = palloc(size*2);
- loc = result+1; // skip type
+
+ loc = buf+1; // skip type
if ( wantbbox ) loc += sizeof(BOX2DFLOAT4); // skip box
if ( exploded->SRID != -1 ) loc += 4; // skip SRID
// If we have more then one type of geom
// write that number in the 'ngeoms' field of the
- // output serialized form (internal geoms would be multi themself)
- if ( ntypes > 1 )
- {
+ // output serialized form (internal geoms would be multi themself).
+ // Else rewind location pointer so to overwrite result type.
+ if ( ntypes > 1 ) {
memcpy(loc, &ntypes, 4);
loc += 4;
- }
-
- else
- {
+ } else {
loc--; // let the type be specified later.
}
for (i=0; i<exploded->npoints; i++)
{
int subsize;
-
point = lwpoint_deserialize(exploded->points[i]);
point->SRID = -1;
- ser = lwpoint_serialize(point);
- subsize = lwpoint_findlength(ser);
- memcpy(loc, ser, subsize);
+ lwpoint_serialize_buf(point, loc, &subsize);
+ pfree_point(point);
loc += subsize;
}
// Serialize lines stripping BBOX and SRID if any
for (i=0; i<exploded->nlines; i++)
{
- char *ser;
int subsize;
line = lwline_deserialize(exploded->lines[i]);
if ( line == NULL )
{
elog(ERROR, "Error deserializing %dnt line from exploded geom", i);
- return NULL;
+ return;
}
line->SRID = -1;
- ser = lwline_serialize(line);
+ lwline_serialize_buf(line, loc, &subsize);
pfree_line(line);
- subsize = lwline_findlength(ser);
- memcpy(loc, ser, subsize);
- pfree(ser);
loc += subsize;
}
// Serialize polys stripping BBOX and SRID if any
for (i=0; i<exploded->npolys; i++)
{
- char *ser;
int subsize;
poly = lwpoly_deserialize(exploded->polys[i]);
if ( poly == NULL )
{
elog(ERROR, "Error deserializing %dnt polygon from exploded geom", i);
- return NULL;
+ return;
}
poly->SRID = -1;
- ser = lwpoly_serialize(poly);
+ lwpoly_serialize_buf(poly, loc, &subsize);
pfree_polygon(poly);
- subsize = lwpoly_findlength(ser);
-#ifdef DEBUG
- elog(NOTICE, "size of polygon %d: %d", i, subsize);
-#endif
- memcpy(loc, ser, subsize);
- pfree(ser);
loc += subsize;
}
+ // Register now the number of written bytes
+ *retsize = (loc-buf);
+
// Ok. now we need to add type, SRID and bbox
- result[0] = lwgeom_makeType_full(exploded->ndims,
+ buf[0] = lwgeom_makeType_full(exploded->ndims,
(exploded->SRID!=-1), outtype, wantbbox);
- loc = result+1;
+ loc = buf+1;
if ( wantbbox )
{
- box3d = lw_geom_getBB_simple(result);
+ box3d = lw_geom_getBB_simple(buf);
box2d = box3d_to_box2df(box3d);
memcpy(loc, box2d, sizeof(BOX2DFLOAT4));
loc += sizeof(BOX2DFLOAT4);
#ifdef DEBUG
elog(NOTICE, "lwexploded_serialize finished");
- elog(NOTICE, " type: %d", lwgeom_getType(result[0]));
- elog(NOTICE, " SRID: %d", lwgeom_getsrid(result));
- if ( lwgeom_hasBBOX(result[0]) )
+ elog(NOTICE, " type: %d", lwgeom_getType(buf[0]));
+ elog(NOTICE, " SRID: %d", lwgeom_getsrid(buf));
+ if ( lwgeom_hasBBOX(buf[0]) )
{
{
BOX2DFLOAT4 boxbuf;
- getbox2d_p(result, &boxbuf);
+ getbox2d_p(buf, &boxbuf);
elog(NOTICE, " BBOX: %f,%f %f,%f",
boxbuf.xmin, boxbuf.ymin,
boxbuf.xmax, boxbuf.ymax);
}
}
- elog(NOTICE, " numgeoms: %d", lwgeom_getnumgeometries(result));
-#endif
-
-#ifdef DEBUG_EXPLODED
-checkexplodedsize(result, exploded, size*2, wantbbox);
+ elog(NOTICE, " numgeoms: %d", lwgeom_getnumgeometries(buf));
#endif
- return result;
+ return;
}
#ifdef DEBUG_EXPLODED
}
/* structure is empty */
- if ( ! ntypes ) return 0;
+ if ( ! ntypes ) return lwgeom_empty_length(exploded->SRID);
/* multi-typed geom (collection), add collection header */
if ( ntypes > 1 )
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