This patch adds support for PBVH drawing in EEVEE. Notes: # PBVH_FACES only. For Multires we'll need an API to get/cache attributes. DynTopo support will be merged in later with sculpt-dev's DynTopo implementation. # Supports vertex color and UV attributes only; other types can be added fairly easily though. # Workbench only sends the active vertex color and UV layers to the GPU. # Added a new draw engine API method, DRW_cdlayer_attr_aliases_add. Please review. # The vertex format object is now stored in the pbvh. Reviewed By: Clément Foucault & Brecht Van Lommel & Jeroen Bakker Differential Revision: https://developer.blender.org/D13897 Ref D13897