Add PC_MakePatch(pcid integer, values float8[])

Add PC_MakePatch to create a patch from a pcid and an array of float8 values.

Author: tsl-karlp

README.md

@@ -251,6 +251,18 @@ Now that you have created two tables, you'll see entries for them in the `pointc
 >     INSERT INTO patches (pa)
 >     SELECT PC_Patch(pt) FROM points GROUP BY id/10;
 
+
+**PC_MakePatch(pcid integer, vals float8[])** returns **pcpatch**
+
+> Given a valid `pcid` schema number and an array of doubles that matches the schema, construct a new `pcpatch`.
+> Array size must be a multiple of the number of dimensions.
+>
+>     SELECT PC_AsText(PC_MakePatch(1, ARRAY[-126.99,45.01,1,0, -126.98,45.02,2,0, -126.97,45.03,3,0]));
+
+>     {"pcid":1,"pts":[
+>      [-126.99,45.01,1,0],[-126.98,45.02,2,0],[-126.97,45.03,3,0]
+>     ]}
+
 **PC_NumPoints(p pcpatch)** returns **integer**
 
 > Return the number of points in this patch.

lib/cunit/cu_pc_patch.c

@@ -187,8 +187,8 @@ test_patch_hex_out()
 	double d0[4] = { 0.02, 0.03, 0.05, 6 };
 	double d1[4] = { 0.02, 0.03, 0.05, 8 };
 
-	PCPOINT *pt0 = pc_point_from_double_array(simpleschema, d0, 4);
-	PCPOINT *pt1 = pc_point_from_double_array(simpleschema, d1, 4);
+	PCPOINT *pt0 = pc_point_from_double_array(simpleschema, d0, 0, 4);
+	PCPOINT *pt1 = pc_point_from_double_array(simpleschema, d1, 0, 4);
 
 	PCPATCH_UNCOMPRESSED *pa;
 	uint8_t *wkb;

lib/pc_api.h

@@ -322,8 +322,8 @@ PCPOINT* pc_point_make(const PCSCHEMA *s);
 /** Create a new readonly PCPOINT on top of a data buffer */
 PCPOINT* pc_point_from_data(const PCSCHEMA *s, const uint8_t *data);
 
-/** Create a new read/write PCPOINT from a double array */
-PCPOINT* pc_point_from_double_array(const PCSCHEMA *s, double *array, uint32_t nelems);
+/** Create a new read/write PCPOINT from a double array  with an offset */
+PCPOINT* pc_point_from_double_array(const PCSCHEMA *s, double *array, uint32_t offset, uint32_t stride);
 
 /**
 * Return an allocated double array of doubles representing point values

lib/pc_point.c

@@ -217,8 +217,9 @@ pc_point_to_string(const PCPOINT *pt)
 	return str;
 }
 
+
 PCPOINT *
-pc_point_from_double_array(const PCSCHEMA *s, double *array, uint32_t nelems)
+pc_point_from_double_array(const PCSCHEMA *s, double *array, uint32_t offset, uint32_t stride)
 {
 	int i;
 	PCPOINT *pt;
@@ -229,9 +230,9 @@ pc_point_from_double_array(const PCSCHEMA *s, double *array, uint32_t nelems)
 		return NULL;
 	}
 
-	if ( s->ndims != nelems )
+	if ( stride != s->ndims )
 	{
-		pcerror("number of elements in schema and array differ in pc_point_from_double_array");
+		pcerror("number of elements in schema and array do not match in pc_point_from_double_array");
 		return NULL;
 	}
 
@@ -241,9 +242,9 @@ pc_point_from_double_array(const PCSCHEMA *s, double *array, uint32_t nelems)
 	pt->schema = s;
 	pt->readonly = PC_FALSE;
 
-	for ( i = 0; i < nelems; i++ )
+	for ( i = 0; i < stride; i++ )
 	{
-		if ( PC_FAILURE == pc_point_set_double_by_index(pt, i, array[i]) )
+		if ( PC_FAILURE == pc_point_set_double_by_index(pt, i, array[offset + i]) )
 		{
 			pcerror("failed to write value into dimension %d in pc_point_from_double_array", i);
 			return NULL;

pgsql/expected/pointcloud.out

@@ -728,4 +728,11 @@ FROM ( SELECT PC_Patch(PC_MakePoint(1, ARRAY[-1,0,4862413,1])) p ) foo;
  {"pcid":10,"pts":[[-1,0,1,1,1,1,1]]} | "none"
 (1 row)
 
+-- test PC_Patch from float8 array
+SELECT pc_astext(PC_MakePatch(1, ARRAY[-1,0,5,1, -1,0,6,1, -1,0,7,1]));
+                      pc_astext                      
+-----------------------------------------------------
+ {"pcid":1,"pts":[[-1,0,5,1],[-1,0,6,1],[-1,0,7,1]]}
+(1 row)
+
 TRUNCATE pointcloud_formats;

pgsql/pc_access.c

@@ -23,6 +23,7 @@ void pc_cstring_array_free(const char **array, int nelems);
 Datum pcpoint_get_value(PG_FUNCTION_ARGS);
 Datum pcpoint_get_values(PG_FUNCTION_ARGS);
 Datum pcpatch_from_pcpoint_array(PG_FUNCTION_ARGS);
+Datum pcpatch_from_float_array(PG_FUNCTION_ARGS);
 Datum pcpatch_from_pcpatch_array(PG_FUNCTION_ARGS);
 Datum pcpatch_uncompress(PG_FUNCTION_ARGS);
 Datum pcpatch_compress(PG_FUNCTION_ARGS);
@@ -329,6 +330,60 @@ Datum pcpatch_from_pcpoint_array(PG_FUNCTION_ARGS)
 	PG_RETURN_POINTER(serpa);
 }
 
+
+PG_FUNCTION_INFO_V1(pcpatch_from_float_array);
+Datum pcpatch_from_float_array(PG_FUNCTION_ARGS)
+{
+	int i, ndims, nelems, npoints;
+	float8 *vals;
+	PCPATCH *pa;
+	PCPOINTLIST *pl;
+	SERIALIZED_PATCH *serpa;
+	uint32 pcid = PG_GETARG_INT32(0);
+	ArrayType *arrptr = PG_GETARG_ARRAYTYPE_P(1);
+	PCSCHEMA *schema = pc_schema_from_pcid(pcid, fcinfo);
+
+	if ( ! schema )
+		elog(ERROR, "unable to load schema for pcid = %d", pcid);
+
+	if ( ARR_ELEMTYPE(arrptr) != FLOAT8OID )
+		elog(ERROR, "array must be of float8[]");
+
+	if ( ARR_NDIM(arrptr) != 1 )
+		elog(ERROR, "float8[] must have one dimension");
+
+	if ( ARR_HASNULL(arrptr) )
+		elog(ERROR, "float8[] must not have null elements");
+
+	ndims = schema->ndims;
+	nelems = ARR_DIMS(arrptr)[0];
+
+	if ( nelems % ndims != 0 ) {
+		elog(ERROR, "array dimensions do not match schema dimensions of pcid = %d", pcid);
+	}
+
+	npoints = nelems / ndims;
+
+	vals = (float8*) ARR_DATA_PTR(arrptr);
+	pl = pc_pointlist_make(nelems);
+
+	for ( i = 0; i < npoints; ++i ) {
+
+		PCPOINT* pt = pc_point_from_double_array(schema, vals, i * ndims, ndims);
+		pc_pointlist_add_point(pl, pt);
+	}
+
+	pa = pc_patch_from_pointlist(pl);
+	pc_pointlist_free(pl);
+	if ( ! pa )
+		PG_RETURN_NULL();
+
+	serpa = pc_patch_serialize(pa, NULL);
+
+	pc_patch_free(pa);
+	PG_RETURN_POINTER(serpa);
+}
+
 typedef struct
 {
 	ArrayBuildState *s;

pgsql/pc_inout.c

@@ -224,7 +224,7 @@ Datum pcpoint_from_double_array(PG_FUNCTION_ARGS)
 		elog(ERROR, "array dimensions do not match schema dimensions of pcid = %d", pcid);
 
 	vals = (float8*) ARR_DATA_PTR(arrptr);
-	pt = pc_point_from_double_array(schema, vals, nelems);
+	pt = pc_point_from_double_array(schema, vals, 0, nelems);
 
 	serpt = pc_point_serialize(pt);
 	pc_point_free(pt);

pgsql/pointcloud.sql.in

@@ -229,6 +229,11 @@ CREATE OR REPLACE FUNCTION PC_AsBinary(p pcpoint)
 --  PCPATCH
 -------------------------------------------------------------------
 
+
+CREATE OR REPLACE FUNCTION PC_MakePatch(pcid integer, vals float8[])
+	RETURNS pcpatch AS 'MODULE_PATHNAME', 'pcpatch_from_float_array'
+	LANGUAGE 'c' IMMUTABLE STRICT;
+
 CREATE OR REPLACE FUNCTION pcpatch_in(cstring)
 	RETURNS pcpatch AS 'MODULE_PATHNAME', 'pcpatch_in'
 	LANGUAGE 'c' IMMUTABLE STRICT;

pgsql/sql/pointcloud.sql

@@ -451,4 +451,9 @@ SELECT
   PC_AsText(PC_Transform(p, 10, 1.0)) t, PC_Summary(PC_Transform(p, 10, 1.0))::json->'compr' c
 FROM ( SELECT PC_Patch(PC_MakePoint(1, ARRAY[-1,0,4862413,1])) p ) foo;
 
+
+-- test PC_Patch from float8 array
+SELECT pc_astext(PC_MakePatch(1, ARRAY[-1,0,5,1, -1,0,6,1, -1,0,7,1]));
+
+
 TRUNCATE pointcloud_formats;