Making it difficult to manage which classes are being loaded and when.Blender is a free and open-source 3D computer graphics software product used for creating animated films, visual effects, art, 3D printed models, interactive 3D applications and video games. This becomes problematic when a script imports classes from another module Meaning there would be no distinction between importing a module or loading its classes into Blender. If the register calls were placed in the body of the script, registration would be called on import, The register/unregister calls are used so it’s possible to toggle add-ons and reload scripts while Blender runs. Since register won’t re-run when a new blend file is loaded. You can also use them for internal purposes setting up data for your own tools but take care These functions usually appear at the bottom of the script containing class registration sometimes adding menu items. unregister_class ( SimpleOperator ) if _name_ = '_main_' : register () register_class ( SimpleOperator ) def unregister (): bpy. Operator ): ''' See example above ''' def register (): bpy. The registration checks will use attributes and functions defined in parent classes. Regarding inheritance, Blender doesn’t impose restrictions on the kinds of class inheritance used, Lastly the register function is called, this takes the class and loads it into Blender. Next see the execute function, which takes an instance of the operator and the current context.Ī common prefix is not used for functions. This is a convention used to distinguish Blender properties from those you add yourself. Used so we know if this is an Operator and not a Panel when registering.īoth class properties start with a bl_ prefix. This is common for all classes which can be integrated with Blender and register_class ( SimpleOperator )įirst note that we subclass a member of bpy.types,

Operator ): bl_idname = 'object.simple_operator' bl_label = 'Tool Name' def execute ( self, context ): print ( 'Hello World' ) return bpy.

Blender 2.79 b