•Adding ores or other blocks to world generation
Atm it supports adding/changing default ore generation via C#. I'd like to extend that to XML.
•Adding in HUD elements, (in the fashion of say the hotbar, or other various game HUD pieces)
Yes, via C#
•Adding script commands, and what would be feasible with it
Not yet
•Adding loot to cave chest loot table
No
•Adding different types of random spawn chests with unique loot tables to the vanilla game
No
•Adding in world gen things like the caves that cave chests spawn in, or little pools of liquid for modded in liquids, or trees/other various flora, or structures like small buildings or castles
Not yet
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Regarding the first item on the list. Say I want to add an ore, will I be able to have them spawn naturally? What if I want to add other stone types to spawn in layers like marble or granite do, but I don't want to remove any of the default stone layers? Can I do that?
Yes via C#
What about if I want a different kind of grass to spawn in along side normal grass, not patchy like if grassy stone and grass shaded are, sort of like maybe a... makeshift biome thing?
Not yet
Are the no's going to stay a no? It seems like it'd be a useful feature to be able to add loot to the cave chest loot table and create your own random loot chests that have different types of weapins/blocks/armours.
The ones listed as not yet. Are they going to be possible via XML?
The ones listed as yes,C#. Will they be extended to XML.
Basically, I'm asking how much will be capable in XML. XML seems pretty convenient.