func (m *Map) printLayerStatus() {
n := C.mapnik_map_layer_count(m.m)
for i := 0; i < int(n); i++ {
fmt.Println(
C.GoString(C.mapnik_map_layer_name(m.m, C.size_t(i))),
C.mapnik_map_layer_is_active(m.m, C.size_t(i)),
)
}
}
// SelectLayers enables/disables single layers. LayerSelector or SelectorFunc gets called for each layer.
func (m *Map) SelectLayers(selector LayerSelector) {
m.storeLayerStatus()
n := C.mapnik_map_layer_count(m.m)
for i := 0; i < int(n); i++ {
layerName := C.GoString(C.mapnik_map_layer_name(m.m, C.size_t(i)))
switch selector.Select(layerName) {
case Include:
C.mapnik_map_layer_set_active(m.m, C.size_t(i), 1)
case Exclude:
C.mapnik_map_layer_set_active(m.m, C.size_t(i), 0)
case Default:
}
}
}