/*
{ok, DataSource} = lgeo_ogr:open("test/polygon.shp"),
{ok, Layer} = lgeo_ogr:ds_get_layer(DataSource, 0),
{ok, Feature} = lgeo_ogr:l_get_feature(Layer, 0),
{ok, Fields} = lgeo_ogr:f_get_fields(Feature).
{1,"first"}
*/
static ERL_NIF_TERM
f_get_fields(ErlNifEnv* env, int argc, const ERL_NIF_TERM argv[])
{
EnvFeature_t **feature;
ERL_NIF_TERM eterm;
if (argc != 1) {
return enif_make_badarg(env);
}
if(!enif_get_resource(env, argv[0], OGR_F_RESOURCE, (void**)&feature)) {
return enif_make_badarg(env);
}
OGRFeatureDefnH feature_defn = OGR_F_GetDefnRef((**feature).obj);
int count = OGR_FD_GetFieldCount(feature_defn);
ERL_NIF_TERM *arr = (ERL_NIF_TERM *) malloc(sizeof(ERL_NIF_TERM)*count);
int index;
for(index=0; index<count; index++)
{
OGRFieldDefnH field_defn = OGR_FD_GetFieldDefn(feature_defn, index);
if(OGR_Fld_GetType(field_defn) == OFTInteger) {
arr[index] = enif_make_int(env,
OGR_F_GetFieldAsInteger((**feature).obj, index));
} else if(OGR_Fld_GetType(field_defn) == OFTReal) {
arr[index] = enif_make_double(env,
OGR_F_GetFieldAsDouble((**feature).obj, index));
} else if(OGR_Fld_GetType(field_defn) == OFTString) {
arr[index] = enif_make_string(env,
OGR_F_GetFieldAsString((**feature).obj, index),
ERL_NIF_LATIN1);
} else {
arr[index] = enif_make_string(env,
OGR_F_GetFieldAsString((**feature).obj, index),
ERL_NIF_LATIN1);
}
}
eterm = enif_make_tuple_from_array(env, arr, index);
free(arr);
return enif_make_tuple2(env, enif_make_atom(env, "ok"), eterm);
}
// Create and add a placement to the current lithograph if it doesn't overlap
// with current labels.
void
simplet_lithograph_add_placement(simplet_lithograph_t *litho,
OGRFeatureH feature, simplet_list_t *styles, cairo_t *proj_ctx) {
simplet_style_t *field = simplet_lookup_style(styles, "text-field");
if(!field) return;
OGRFeatureDefnH defn;
if(!(defn = OGR_F_GetDefnRef(feature))) return;
int idx = OGR_FD_GetFieldIndex(defn, (const char*) field->arg);
if(idx < 0) return;
// Find the largest sub geometry of a particular multi-geometry.
OGRGeometryH super = OGR_F_GetGeometryRef(feature);
OGRGeometryH geom = super;
double area = 0.0;
switch(wkbFlatten(OGR_G_GetGeometryType(super))) {
case wkbMultiPolygon:
case wkbGeometryCollection:
for(int i = 0; i < OGR_G_GetGeometryCount(super); i++) {
OGRGeometryH subgeom = OGR_G_GetGeometryRef(super, i);
if(subgeom == NULL) continue;
double ar = OGR_G_Area(subgeom);
if(ar > area) {
geom = subgeom;
area = ar;
}
}
break;
default:
;
}
// Find the center of our geometry. This sometimes throws an invalid geometry
// error, so there is a slight bug here somehow.
OGRGeometryH center;
if(!(center = OGR_G_CreateGeometry(wkbPoint))) return;
if(OGR_G_Centroid(geom, center) == OGRERR_FAILURE) {
OGR_G_DestroyGeometry(center);
return;
}
// Turn font hinting off
cairo_font_options_t *opts;
if(!(opts = cairo_font_options_create())){
OGR_G_DestroyGeometry(center);
return;
}
cairo_font_options_set_hint_style(opts, CAIRO_HINT_STYLE_NONE);
cairo_font_options_set_hint_metrics(opts, CAIRO_HINT_METRICS_OFF);
pango_cairo_context_set_font_options(litho->pango_ctx, opts);
cairo_font_options_destroy(opts);
// Get the field containing the text for the label.
char *txt = simplet_copy_string(OGR_F_GetFieldAsString(feature, idx));
PangoLayout *layout = pango_layout_new(litho->pango_ctx);
pango_layout_set_text(layout, txt, -1);
free(txt);
// Grab the font to use and apply tracking.
simplet_style_t *font = simplet_lookup_style(styles, "font");
simplet_apply_styles(layout, styles, "letter-spacing", NULL);
const char *font_family;
if(!font)
font_family = "helvetica 12px";
else
font_family = font->arg;
PangoFontDescription *desc = pango_font_description_from_string(font_family);
pango_layout_set_font_description(layout, desc);
pango_font_description_free(desc);
double x = OGR_G_GetX(center, 0), y = OGR_G_GetY(center, 0);
cairo_user_to_device(proj_ctx, &x, &y);
// Finally try the placement and test for overlaps.
try_and_insert_placement(litho, layout, x, y);
OGR_G_DestroyGeometry(center);
}
bool QgsShapeFile::scanGeometries()
{
QProgressDialog *sg = new QProgressDialog();
sg->setMinimum( 0 );
sg->setMaximum( 0 );
QString label = tr( "Scanning " );
label += fileName;
sg->setLabel( new QLabel( label ) );
sg->show();
qApp->processEvents();
OGRFeatureH feat;
OGRwkbGeometryType currentType = wkbUnknown;
bool multi = false;
while (( feat = OGR_L_GetNextFeature( ogrLayer ) ) )
{
qApp->processEvents();
// feat->DumpReadable(NULL);
OGRGeometryH geom = OGR_F_GetGeometryRef( feat );
if ( geom )
{
QString gml = OGR_G_ExportToGML( geom );
// QgsDebugMsg(gml);
if ( gml.indexOf( "gml:Multi" ) > -1 )
{
// QgsDebugMsg("MULTI Part Feature detected");
multi = true;
}
OGRFeatureDefnH fDef = OGR_F_GetDefnRef( feat );
OGRwkbGeometryType gType = OGR_FD_GetGeomType( fDef );
// QgsDebugMsg(gType);
if ( gType > currentType )
{
currentType = gType;
}
if ( gType < currentType )
{
QgsDebugMsg( QString( "Encountered inconsistent geometry type %1" ).arg( gType ) );
}
}
}
// a hack to support 2.5D geometries (their wkb is equivalent to 2D variants
// except that the highest bit is set also). For now we will ignore 3rd coordinate.
hasMoreDimensions = false;
if ( currentType & wkb25DBit )
{
QgsDebugMsg( "Got a shapefile with 2.5D geometry." );
currentType = wkbFlatten( currentType );
hasMoreDimensions = true;
}
OGR_L_ResetReading( ogrLayer );
geom_type = geometries[currentType];
if ( multi && ( geom_type.indexOf( "MULTI" ) == -1 ) )
{
geom_type = "MULTI" + geom_type;
}
delete sg;
// QgsDebugMsg(QString("Geometry type is %1 (%2)").arg(currentType).arg(geometries[currentType]));
return multi;
}
