20121207

20121207
========

Work continues on the UI systems :

- Migrated requpdate() calls to req_update().
- Various fixes and implementation tweaks to filter override items.
Some remaining bugs to be ironed out.
- Disabling direct calls to set the override item list to nil or
set_o_items. The associated array ought to deal with this.
- More code clean-up to simplify overrides list handling in case of
multi-selection, etc.

20121206
========

Brace yourself. Here's the big set of UI changes related to filtering
the override items listbox based on selected override type, and to
making the code less aggravating to read. Many thanks to both Lernie
and Matt for their help in showing me where I was going wrong in the
original attempt to implement the listbox filtering based on a
selection elsewhere in the UI. I wasn't far off, but overlooked the
multi-selection aware nature of the listboxes and a couple of other
issues.

- Changed the obscure c3 listbox references to
'gad_SceneItems_forPasses_Listview'
- Changed the obscure c3_5 listbox references to
'gad_SceneItems_forOverrides_Listview'
- Changed all other obscure UI references to explicit labels; more
readable/understandable than 'c0_5'
- Removing lots of tempNumber usage that confuses intent of code.
- Added debug state button to UI. Intent is to enable developer to
block rendering and to have scene files open for inspection during
development of new support in PP. Only shown in dev mode.
 - Render functions now respect this setting.
 - Setting retained across sessions. Default is off.
- Switched dev and debug handling to integers to make handling easier.
0 is off, 1 is on.
- Split Passes and Overrides UDFs out of main file to two separate ones.
- Reworked the override item list generation code - much simpler.
- Fixed bug p0012 - hadn't yet hooked up the override lists in the
reprocess UI code.
- Initial migration of override items listbox code to new filtered
list. This will be bringing breakage aplenty.... There's some
additional subtlety in tracking selected items, it seems.
- Scene Master special item gets an internal genus type of 0 to filter
against the type6 override.