[B18] Unbuilt walls get cancelled during save/load if wall tile contains an item

[Calahan]

1. What the circumstances were & 2. What happened.

If there are partially completed wall tiles (ie. they have the materials delivered to them) with items occupying the same tile when the game is saved, then when the game is reloaded the wall construction is cancelled and the materials deposited to the tile south of the wall tile. Seemingly irrespective of what was originally occupying that tile. eg. (following text diagrams summarise my testing)
(w= partially completed wall tile, W completed wall tile, M= Mountain tile)

- If there is a mountain tile to the south,

www
MMM

then the mountain tiles simple disappear and is replaced by the 5X materials that were previously assigned to the partially completed wall tiles.

- If there is a completed wall tile to the south,

www
WWW

then the completed wall tiles also disappear and the respective 5X materials from those completed wall tiles get deposited to their south. If there are then mountain tiles to the south of the completed tiles,

www
WWW
MMM

then once again those mountain tiles disappear and are replaced by the 5X materials from the completed wall tiles.

- I couldn't get an unlimited chain reaction to work though, as if there are two layers of completed walls then only some of the wall tiles disappear, and the materials either group together or squirt out to the side, thereby preventing a chain reaction. (maybe having the layer of walls of different materials would prevent grouping an continue the reaction?)

- I haven't done extensive testing to see what other objects this might apply to. Although some brief testing of partially constructed:

--- plant pots (for 1x1 objects) and workbenches (for object larger than 1x1) do retain their materials when saving/loading.
--- But NPD's don't retain their materials, and like wall tiles the construction is cancelled upon loading the game. But unlike wall tiles there is no displacement of mountain tiles etc. (presumably because of the size of the NPD meaning no shortage of space, so no need to "create" space for the materials).
--- But Campfire's do retain their materials, which was a surprise actually, as Pawns can't walk on them, nor can items be dropped on them, so I assumed they'd have the same bug. So perhaps it's only objects that have wall-like properties, such as (obviously) walls and NPD's etc.

 
Besides the obviously bugged behaviour here, this is also a pretty exploitable way to quickly remove any wall or mountain tile (such as to reduce the temp when combating an indoor fire). And a good way to deconstruct walls without losing the 1-2 materials you lose during deconstruction. It's also a great way to lose your entire meat supply in a day when you don't notice your under construction freezer suddenly has a hole in the wall, and 5 blocks sitting where a mountain tile used to be. Doh! (which is exactly how I discovered this bug).


3. What you expected to happen.

None of the above. Or simply, I'd expect partially constructed wall tiles to retain their materials (not get cancelled) when saving/loading.


4. Steps to reproduce the bug.

Without the save:

Arrange the following setup (P= Pawn, w= partially completed wall tile, M= Mountain tile). (or see the attached image for how the save game was setup).

P
w
M

Then have the Pawn either drop what they are hauling (by drafting them), or drop something from their inventory/wearing so that said item lands on the partially completed wall tile.


5. Savegame file

From the following save file: http://www103.zippyshare.com/v/QXsE2nrL/file.html (please let me know if it needs reuploading)

1 - Draft the three Pawns (causing them to drop what they were hauling to their south where there are three partially constructed wall tiles).
2 - Save the game.
3 - Load the game you just saved.
4 - Notice how the three partially completed wall tiles have been cancelled, and the three lot of 5X materials from the partially completed wall tiles are now located to their south where there were previously three mountain tiles.


Thank you for your time in reading this.

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