Item Investigation Log

[default-kramer]

Gonna keep track of everything I investigate here.

[default-kramer]

Placed some items in Seawater (from the bucket):

Using the Chunk Editor, I could see that the blockdata IDs were as follows:

• Coneconut Tree 2027
• Gladiolus 2027
• Stone Handrail 1226
• Wooden Fencing 1226
• Seaweed 2027
• Pebbles 2027
• Splinters 2027

I used the Chunk Editor to change the Seaweed and Pebbles to 1226 (in the blockdata only; didn't update any item data). As a result, the Seaweed and Pebbles can now form rooms!

I was hoping that the Seaweed and Pebbles would also gain the collision detection, but it remained unchanged.

The edited items could still be destroyed with the hammer as normal.

Hypothesis: Any item can be made to form rooms by changing its blockdata value. For surface/deep (not full) seawater the magic value is 1226; it will be different if the item is not submerged, or submerged in a different liquid.

Hypothesis: Collision detection is determined from itemdata and not blockdata. This would make sense since there are many different hitboxes based on the shape of the item. Just consider how the builder walks over different items: roofing, coffers, tables, fences, stairs, etc...

[default-kramer]

Next I made a room using the Stone Handrail and the Wooden Fencing. I used the Chunk Editor to change the Stone Handrail's block value from 1226 to 2027. As expected, the room disappeared as soon as I loaded the save:

Simply picking up the Stone Handrail with the gloves and setting it back down was enough to cause it to become a room again.

Also for the record, the Stone Doormat (submerged in Seawater) uses 1760 in the blockdata.

Hypothesis: Any item that normally forms rooms can be made to not form rooms by changing its blockdata value.

[default-kramer]

Using the Chunk Editor's list of liquids and assuming that any value < 1158 is "simple" (not an item), we can see that each kind of liquid appears in runs of 11 consecutive values. The 11 values appear to indicate the shape of the liquid - they always go in this order:

1. Full
2. Shallow
3. Surface
4. Small
5. Surface
6. Surface
7. Surface
8. Surface
9. Surface
10. Surface
11. Full

(Presumably there is detail here not captured in the name. For example, the various "Surface" blocks are probably for different types of corners that occur at the edge of the liquid's extent.)

Each liquid has 10 "banks" of 11 values, the inclusive ranges for Seawater are:

• 1224-1234
• 1313-1323
• 1402-1412
• 1491-1501
• 1580-1590
• 1669-1679
• 1758-1768
• 1847-1857
• 1936-1946
• 2025-2035

Hypothesis: The "bank" is what defines properties like "does it form a room or not". So while the Stone Handrail I mentioned earlier used 1226, any value in the "bank" of 1224-1234 would exhibit the same "forms a room" property, while just rendering the liquid a bit differently.

[default-kramer]

Also note that there is 1 value of separation between each bank of Plasma and the next bank of Clear Water. For example:

• 1235-1245 the first Plasma bank
• 1246 is not a liquid
• 1247-1257 the second Clear Water bank

Hypothesis: Each bank contains 11 values per liquid times 8 liquids, plus one more value for when the item is not submerged. This means each bank contains 11*8+1 = 89 values. All values in each bank will share the same properties (e.g. "does it form a room?"). Because each bank is 89 values and there are 10 banks, we get a total of 890 item IDs. This matches perfectly with 1158 being the first item ID and 2047 being the last, because 1158+890 = 2048.

[default-kramer]

A few results to confirm the theory. The "Seawater" and "Plasma" entries that follow mean the item was submerged in that liquid from the pot in normal (not shallow) mode. You can see that Seawater is always "not submerged minus 20" and Plasma is always "not submerged minus 9".

Bank 1, 1158-1246

• not submerged: 1246
• Seawater: 1226
• Plasma: 1237
• Items tested: Stone Handrail, Wooden Fencing

Bank 7, 1692-1780

• not submerged ID: 1780
• Seawater ID: 1760
• Plasma ID: 1771
• Items tested: Stone Doormat, Connecting Window, Plane-Pane Leadlight, Adobe Window
• NOTE: The following items always get ID 1780; they cannot be submerged: Connecting Window, Plane-Pane Leadlight, Adobe Window

Bank 10, 1959-2047

• not submerged: 2047
• Seawater: 2027
• Plasma: 2038
• Items tested: Coneconut Tree, Gladiolus, Seaweed, Pebbles, Splinters, Pampas Grass, Big Palm Tree, Palm Tree, Silver Birch Stump, Community Chest, Storage Bay, Wardrobe, Wooden Cabinet, Wooden Steps, Stone Steps, Citadel Steps, Coloured Cup, Simple Supper Set, Salad Plate, Simple Bed, Rustic Bed, Straw Mattress, Straw Bedding

[Sapphire645]

I looked at the blockitems (what I'm gonna call Item Shell) a while back and I've forgotten some of it, but the gist is: There are 10 shells:
1246 -> Fence shell
1335 -> Cooking pan shell
1424 -> Rail track shell
1513 -> Roof shell
1602 -> Table shell
1691 -> Light shell
1780 -> Block shell
1869 -> Door shell
1958 -> Door (again? Its what I have, but maybe I wrote it wrong...)
2047 -> Air shell

The structure on IDs works like this:
· 11 IDs per liquid.
->Full, Shallow, Surface, Small, Surface, Surface, Surface, Surface, Surface, Surface, Full (From what I have written)
· For all 8 liquids.
-> Clear, Hot, Poison, Lava, Bottomless, Muddy, Sea and Plasma.
Then the last ID is for air.
Do this for all 10 shells, starting at ID 1158.

What the differences between the shells could be I speculate to be:

1158 - 1246 : Fence shell -> For room detection (1 block tall)
1247 - 1335 : Cooking pan shell -> Beats me...
1336 - 1424 : Rail track shell -> For rail detection?
1425 - 1513 : Roof shell -> Ramp????
1514 - 1602 : Table shell -> For lowering items to the table model
1603 - 1691 : Light shell -> To handle turning on/off when water appears (blocklight does not use this shell, it uses the air shell)
1692 - 1780 : Block shell -> For room detection (2 block tall)
1781 - 1869 : Door shell -> For room detection
1870 - 1958 : Door shell -> For room detection
1959 - 2047 : Air shell -> For room detection

Something interesting is that when placing doors and blocks under liquid, the liquid shells are not used, the air ones are used. So ranges 1781 -1868, 1870 - 1957 and 1959 - 2046 may go unused.