[Bf-taskforce25] Operator standardization

[Blender Institute]

Hi,

We've got now over 250 operators defined, time for some thoughts about 
what good standards are for naming, flags, and property definitions.

Campbell did interesting test with epydoc output, see here:

Operators
http://www.graphicall.org/ftp/ideasman42/html/bpyoperator-module.html
RNA
http://www.graphicall.org/ftp/ideasman42/html/class-tree.html

Some issues we noted;

- operator names should try to keep in mind the part after _OT_ should 
fit as a useful api name. (not MESH_OT_mesh_delete, but MESH_OT_delete)

- selection operators should use default boolean for 'extend' and for 
'deselect' ?

- toggle operators (editmode, vpaint) should get standard enum "set, 
clear, toggle", so the op->invoke() can check for this enum, and 
optionally then handle toggle.

- add a tooltip/doc string to operators, describing the intended 
operation well?

- classify operators well that heavily rely on mouse input, or cannot 
be redone or cannot be used for the py api.

- standard border-select or circle-select ops should not return 'event 
type' property, but some other standard like the default booleans 
'extend' and 'deselect'. Those then can later always become configured 
with modal keymaps.

- in order to make a nice UI after operator executed, the used 
properties should be useful in UI too. When an operator uses internal 
props it should be set as such.

- Transform is currently the most gigantic one... how can we extract 
from a transform operator the useful (used?) ones, and how to 
communicate the api well?

So! I guess people can name more issues, let's get them listed and work 
to a proposal of some kind?

-Ton-

------------------------------------------------------------------------
Ton Roosendaal  Blender Foundation   ton at blender.org    www.blender.org
Blender Institute BV  Entrepotdok 57A  1018AD Amsterdam The Netherlands