Draco18s

You didn't tell the parent class what your gui width and height are, so it assumes the default values, which are out of an assumed total of 256 when calculating UVs (which are what's actually used when drawing the gui).

IStateMapper "serializes" a BlockState into a json string. For example, see this implementation I used in order to use different json files based on the two values of a boolean property: https://github.com/Draco18s/ReasonableRealism/blob/1.12.1/src/main/java/com/draco18s/flowers/states/StateMapperFlowers.java

Correct. 1.12 and 1.15 is so radically different that it is fundamentally impossible.

I've never done it, so I don't know the specific process. But also be aware that multiple faces (or none!) could match that normal vector for an arbitrary block model.

You need to figure out which face of the model you're interested in.

GUI-Slots are, yes. But your button doesn't hook into those mechanisms. You must send a packet. See this (old, 1.12) code: https://github.com/Draco18s/ReasonableRealism/blob/1.12.1/src/main/java/com/draco18s/ores/client/gui/GuiContainerOreCart.java#L77

I am pretty sure this is not what you meant.

Also Forge. https://github.com/MinecraftForge/Documentation

DeferredRegister is newer than @ObjectHolder

Also, look at the creative inventory gui for doing scrolling stuff.

What if some other mod wants to override your item's class with a new class in order to add functionality? Now your mod would think that your item is one thing and the game would think your item was another thing, because it was overwritten in the registry. @ObjectHolder synchronizes those things so that your mod gets the correct reference. What if you want to reference an item from another mod, but don't know if that mod is loaded or not? @ObjectHolder, check it for null.

Static is for things that are members of the class, not to an instance of the class. Math.PI and Math.Pow() are examples. There is no need to call new Math() in order to access those.

You have 14 items in your inventory. All of them have working textures. Mind providing more detail?

A client cannot know it's own external IP address. It has to ask someone else "reply back to me the address this message came from"

I'm not sure what part of YOU DO NOT REQUIRE JAVA CODE was not made painfully clear. You do not need java. No java. No code. Only data json files. Put the json files in the right place and it will be loaded automatically FOR you. You do not need to do anything.

Override the data json files.

Dude. This isn't that hard. Loot tables are json files. Put the json files in the right location and it happens automagically.

Cool. But not relevant. This does not require java code.

You never assign the objects in your BlocksList class to anything.

I doubt it. All of those properties are final, now.

Do that.

1) We support people who make mods, not the people who use them 2) Complain to whomeever put that together 3) 1.7.10 is 5 years, 8 months old. Fucking update already. We don't give a shit what mod you're using that has no modern counter part, we can't support software indefinitely.

Can you please edit your post and click this button next time: Because without doing that your spoiler blocks are 4000 pixels tall and completely useless.

Those are graphical assets, but they are not in the UI. Draw what the player will see when they open their inventory.

I have never said it's not possible, I've said that you have to replicate the behavior yourself in an event handler because the vanilla code cannot be used.