int geos_buffer(struct Map_info *In, struct Map_info *Out,
struct Map_info *Buf, int id, int type, double da,
struct spatial_index *si,
struct line_cats *Cats,
struct buf_contours **arr_bc,
int *buffers_count, int *arr_bc_alloc, int flat, int no_caps)
{
GEOSGeometry *IGeom = NULL;
GEOSGeometry *OGeom = NULL;
G_debug(3, "geos_buffer(): id=%d", id);
if (type == GV_AREA)
IGeom = Vect_read_area_geos(In, id);
else
IGeom = Vect_read_line_geos(In, id, &type);
/* GEOS code comment on the number of quadrant segments:
* A value of 8 gives less than 2% max error in the buffer distance.
* For a max error of < 1%, use QS = 12.
* For a max error of < 0.1%, use QS = 18. */
#ifdef GEOS_3_3
if (flat || no_caps) {
GEOSBufferParams* geos_params = GEOSBufferParams_create();
GEOSBufferParams_setEndCapStyle(geos_params,
no_caps ? GEOSBUF_CAP_FLAT : GEOSBUF_CAP_SQUARE);
OGeom = GEOSBufferWithParams(IGeom, geos_params, da);
GEOSBufferParams_destroy(geos_params);
}
else {
OGeom = GEOSBuffer(IGeom, da, 12);
}
#else
OGeom = GEOSBuffer(IGeom, da, 12);
#endif
if (!OGeom) {
G_fatal_error(_("Buffering failed (feature %d)"), id);
}
geom2ring(OGeom, Out, Buf, si, Cats, arr_bc, buffers_count, arr_bc_alloc);
if (IGeom)
GEOSGeom_destroy(IGeom);
if (OGeom)
GEOSGeom_destroy(OGeom);
return 1;
}
void object::test<1>
()
{
numcalls = 0;
initGEOS(notice, notice);
GEOS_interruptRegisterCallback(countCalls);
ensure_equals(numcalls, 0);
GEOSGeometry* geom1 = GEOSGeomFromWKT("LINESTRING(0 0, 1 0)");
ensure("GEOSGeomFromWKT failed", nullptr != geom1);
GEOSGeometry* geom2 = GEOSBuffer(geom1, 1, 8);
ensure("GEOSBufferWithStyle failed", nullptr != geom2);
ensure("interrupt callback never called", numcalls > 0);
GEOSGeom_destroy(geom1);
GEOSGeom_destroy(geom2);
GEOS_interruptRegisterCallback(nullptr); /* unregister */
finishGEOS();
}
Handle<Value> Geometry::Buffer(const Arguments& args)
{
HandleScope scope;
double width;
int quadsegs = 8;
if (args.Length() < 1)
return ThrowException(String::New("requires width argument"));
if (!args[0]->IsNumber())
return ThrowException(Exception::TypeError(String::New("width argument must be a number")));
Geometry *geom = ObjectWrap::Unwrap<Geometry>(args.This());
width = args[0]->NumberValue();
if (args.Length() == 2)
quadsegs = args[1]->Int32Value();
GEOSGeometry *buffer = GEOSBuffer(geom->geos_geom_, width, quadsegs);
if (buffer == NULL)
return ThrowException(String::New("couldn't buffer geometry"));
Handle<Object> buffer_obj = WrapNewGEOSGeometry(buffer);
return scope.Close(buffer_obj);
}
void object::test<4>
()
{
initGEOS(notice, notice);
GEOSGeometry* geom1 = GEOSGeomFromWKT("LINESTRING(0 0, 1 0)");
ensure("GEOSGeomFromWKT failed", nullptr != geom1);
GEOS_interruptRegisterCallback(interruptNow);
GEOSGeometry* geom2 = GEOSBuffer(geom1, 1, 8);
ensure("GEOSBuffer wasn't interrupted", nullptr == geom2);
GEOS_interruptRegisterCallback(nullptr); /* unregister */
// TODO: check the actual exception ? (sent to notice() callback)
GEOSGeom_destroy(geom1);
finishGEOS();
}
shapeObj *msGEOSBuffer(shapeObj *shape, double width)
{
#ifdef USE_GEOS
GEOSGeom g1, g2;
if(!shape)
return NULL;
if(!shape->geometry) /* if no geometry for the shape then build one */
shape->geometry = (GEOSGeom) msGEOSShape2Geometry(shape);
g1 = (GEOSGeom) shape->geometry;
if(!g1) return NULL;
g2 = GEOSBuffer(g1, width, 30);
return msGEOSGeometry2Shape(g2);
#else
msSetError(MS_GEOSERR, "GEOS support is not available.", "msGEOSBuffer()");
return NULL;
#endif
}
char *msudf_buffer(UDF_INIT *initid,UDF_ARGS *args, char *buf,
unsigned long *length, char *is_null, char *error)
{
char *result;
GEOSGeom geom1,geom2;
double buffer;
int quadsegs;
DEBUG("msudf_buffer");
geom1 = msudf_getGeometry((unsigned char *)args->args[0],args->lengths[0]);
if (geom1 == NULL) {
strcpy(error,"Invalid geometry.");
*is_null = 1;
return NULL;
}
buffer = *((double*) args->args[1]);
if (args->arg_count > 2 && args->arg_type[2] == INT_RESULT) {
quadsegs = *((int *)args->args[2]);
} else {
quadsegs = 8;
}
geom2 = GEOSBuffer(geom1,buffer,quadsegs);
if (geom2 != NULL) {
GEOSSetSRID(geom2,GEOSGetSRID(geom1));
result = msudf_returnGeometry(initid,length,geom2);
GEOSGeom_destroy(geom1);
GEOSGeom_destroy(geom2);
return result;
} else {
GEOSGeom_destroy(geom1);
*is_null = 1;
return NULL;
}
}
void object::test<5>
()
{
numcalls = 0;
initGEOS(notice, notice);
GEOSGeometry* geom1 = GEOSGeomFromWKT("LINESTRING(0 0, 1 0)");
ensure("GEOSGeomFromWKT failed", nullptr != geom1);
GEOS_interruptRegisterCallback(interruptNow);
nextcb = GEOS_interruptRegisterCallback(countCalls);
GEOSGeometry* geom2 = GEOSBuffer(geom1, 1, 8);
ensure("GEOSBuffer wasn't interrupted", nullptr == geom2);
ensure_equals(numcalls, 1);
GEOS_interruptRegisterCallback(nullptr); /* unregister */
nextcb = nullptr;
GEOSGeom_destroy(geom1);
finishGEOS();
}
