The problem was that the particle system modifier was reading ob->derivedDeform
during modifier stack evaluation. Due to the mesh -> DM conversion this was no
longer set leading to wrong results.
In fact we don't really need the deformed mesh, just the original mesh topology
for face/poly index remapping. So the solution is to use that instead.
Just as with my earlier fix for bones (0492e56fec),
here we're reading evaluated object values into the "i" versions of each transform
property, and using the original/non-evaluated data for the pointers.
XXX:
What's not clear though is what we should be doing with the "BKE_object_where_is_calc()"
calls here. They currently use ob, but that probably shouldn't happen... and ob_eval
should in theory have a more up-to-date version of what it would need to evaluate!
* Added BKE_object_get_evaluated_mesh, which can also be used outside of
Modifier context.
* BKE_modifier_get_evaluated_mesh_from_object is now a dummy wrapper
around BKE_object_get_evaluated_mesh, we do not need anything special
anymore for RENDER quality option, since this is supposed to be handled
at depsgraph level... Maybe we can get rid of it at some point, but kind
of like the idea of keeping it for now, sounds more consitent.
* Always use BKE_id_new, unless you have a very good reason to use
lower-level code!
* Prefer to pass actual ID user pointer to functions like id_us_plus & co,
rather than 'floating' ID pointer, when possible. It makes it more clear
who is the user we increase count for!
Don't store pointers to ViewLayer in the workspace, only names. Add specific
relation type since the generic mechanism makes the code hard to follow.
Integrate with pointer restore for undo and library remapping code to avoid
data going out of sync.
Also add relation automatically if there doesn't exists one yet in
BKE_workspace_view_layer_get, because in general it's really hard to ensure
it will exist when making arbitrary scene changes.
Differential Revision: https://developer.blender.org/D3432
