From 8c44793228750537c08ea7b19fc18df0138f9501 Mon Sep 17 00:00:00 2001 From: Sergey Sharybin Date: Wed, 23 Mar 2022 12:05:47 +0100 Subject: Implement C++ methods for DNA structures This change makes it possible to add implementation of common C++ methods for DNA structures which helps ensuring unsafe operations like shallow copy are done explicitly. For example, creating a shallow copy used to be: Object temp_object = *input_object; In the C++ context it was seen like the temp_object is properly decoupled from the input object, while in the reality is it not. Now this code becomes: Object temp_object = blender::dna::shallow_copy(*input_object); The copy and move constructor and assignment operators are now explicitly disabled. Other than a more explicit resource management this change also solves a lot of warnings generated by the implicitly defined copy constructors w.r.t dealing with deprecated fields. These warnings were generated by Apple Clang when a shallow object copy was created via implicitly defined copy constructor. In order to enable C++ methods for DNA structures a newly added macro `DNA_DEFINE_CXX_METHODS()` is to be used: tpyedef struct Object { DNA_DEFINE_CXX_METHODS(Object) ... } Object; For the shallow copy use `blender::dna::shallow_copy()`. The implementation of the memcpy is hidden via an internal DNA function to avoid pulling `string.h` into every DNA header. This means that the solution does not affect on the headers dependencies. --- Ideally `DNA_shallow_copy` would be defined in a more explicit header, but don;t think we have a suitable one already. Maybe we can introduce `DNA_access.h` ? Differential Revision: https://developer.blender.org/D14427 --- source/blender/depsgraph/intern/depsgraph_query_iter.cc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'source/blender/depsgraph') diff --git a/source/blender/depsgraph/intern/depsgraph_query_iter.cc b/source/blender/depsgraph/intern/depsgraph_query_iter.cc index 5788e8efa07..d5566e4be98 100644 --- a/source/blender/depsgraph/intern/depsgraph_query_iter.cc +++ b/source/blender/depsgraph/intern/depsgraph_query_iter.cc @@ -167,7 +167,7 @@ bool deg_iterator_duplis_step(DEGObjectIterData *data) /* Temporary object to evaluate. */ Object *dupli_parent = data->dupli_parent; Object *temp_dupli_object = &data->temp_dupli_object; - *temp_dupli_object = *dob->ob; + *temp_dupli_object = blender::dna::shallow_copy(*dob->ob); temp_dupli_object->base_flag = dupli_parent->base_flag | BASE_FROM_DUPLI; temp_dupli_object->base_local_view_bits = dupli_parent->base_local_view_bits; temp_dupli_object->runtime.local_collections_bits = -- cgit v1.2.3