get layer name of Dwg_Object

[WaldoJr24]

Hey,
I am trying to filter entities based on their layer names.

Using layers = dwg_get_layers(&dwg);, I have retrieved all the layers. The user can select the layers they want to convert. After the user selects the layers, I need to sort the entities according to their layer names.

This way, only the entities on the user-selected layers will be saved. However, I don't know how to retrieve the layer name of an entity.

I attempted the following approach:

const char* get_layer_name(Dwg_Data *dwg, Dwg_Object *obj) {
    // Use the layer handle to find the actual layer object
    Dwg_Object_Ref *layer_ref = obj->tio.entity->layer;
    if (!layer_ref) {
        printf("Layer reference is NULL\n");
        return NULL;
    }

    Dwg_Object *layer_obj = layer_ref->obj;
    if (!layer_obj) {
        printf("Layer object is NULL\n");
        return NULL;
    }
    Dwg_Object_LAYER *layer = (Dwg_Object_LAYER *)layer_obj;
    if (!layer->name) {
        printf("Layer name is NULL\n");
        return NULL;
    }

    return layer->name;
}

However, I keep encountering a segmentation fault (core dumped) every time I try to access the value in layer->name.

[rurban]

See programs/dwglayers.c

[WaldoJr24]

Thank you!

This is how it works now:

    Dwg_Object* obj = get_first_owned_entity(block_header_ref->obj);
    Dwg_Object_Entity *entity = obj->tio.entity; 
    Dwg_Object_LAYER *entity_layer = dwg_get_entity_layer(entity);
    const char* entity_layer_name = entity_layer->name;