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r3138 | Plagman | 2012-11-09 14:31:02 -0800 (Fri, 09 Nov 2012) | 13 lines

Add automatic tracking to the sector[], wall[], sprite[] and tsprite[]
arrays; any write access to them will run the corresponding hook and write
to the [sector/wall/sprite/tsprite]clean array.

Note: tsprite and sprite use the same hook and require running a few more
instructions per access in order to disambiguiate; this could be made more
optimal (like the other arrays) by clearly separating the types in the game
code.

Note #2: taking a member's address currently marks it dirty because of tons
of helper functions across the editor code. I don't know how many read-only
accesses we have after taking a member address, but it could also be fixed
with some finessing of the code.
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