Choonster

You can also check which player died by checking their UUID. Usernames can change, it's best to compare UUIDs instead as they're constant and unique.

The client only needs Forge installed if the server's mods need to be installed on the client. If none of the server's mods are required on the client, a Vanilla client can join. In what context? If you have a MinecraftServer argument available, use that. If you have an object with a method that returns MinecraftServer (e.g. World#getMinecraftServer), use that. If all else fails, you can use FMLCommonHandler#getMinecraftServerInstance.

serverSideOnly just tells the client to skip loading the mod if it's installed, you need to set the acceptableRemoteVersions property to "*" as well. This tells it to accept any remote version, including none.

1.7.10 is no longer supported by Forge, which means it won't receive updates and you won't get any help with it on this forum.

ArmamentHaki's post. I'll edit in a quote. Edit: I don't think I can on mobile.

For the record, I'm not a moderator; I've just spent a lot of time on here.

Using the JSON system is the recommended way to add recipes (and should be used wherever possible), but you can instantiate and register the recipe from code during RegistryEvent.Register<IRecipe> if necessary.

You've told us what you're trying to do, but you haven't told us what's not working or what you need help with. I'd recommend splitting the active light and facing into two separate properties, which will allow you to use Forge's blockstates format to specify the model once, the texture for each active light and the rotation for each facing rather than having to make a model for each combination of active light and facing.

You need to specify the IRecipeFactory class in the _factories.json file and then create the individual recipe JSON files for any recipes that use the recipe class.

If you look at EntityHorse, you'll see that it registers its DataParameters with their default values in its override of Entity#entityInit (called when the entity is constructed, before its position has been set) and then sets their actual values in its override of EntityLiving#onInitialSpawn (called when the entity is first spawned, after its position has been set). You need to do the same thing.

Just for future reference, you linked to the 1.12.1 branch; which is currently 11 commits behind 1.12.2 (the branch with the latest changes on it). I also recommend linking to a file/folder in a specific commit rather than a branch so that the link will remain pointing to the same code in the future rather than pointing to code that's been changed/removed.

If you look at the implementation of NBTTagCompound#setUniqueId, you'll see that it doesn't use the key you give it directly; it uses two different keys based on it. This means that NBTTagCompound#hasKey will never return true for the key you passed to NBTTagCompound#setUniqueId, you need to use NBTTagCompound#hasUniqueId instead. ItemStack NBT is automatically synced to the client. If you're setting on the server but can't access it from Item#addInformation, you're doing something wrong. Post your code. To create your own API or implement an existing one like IItemHandler/IFluidHandler; or to store data without having to serialise it to/deserialise it from NBT every time you want to access/modify it.

You need to register an IItemColor implementation for your Item with Minecraft's ItemColors instance in init. You can get the instance from a getter in the Minecraft class.

It's one JSON file per recipe, yes. Ah, I missed the version in the thread title. JSON recipes and the recipe registry were added in 1.12, 1.11 still uses the old recipe list system. In 1.11 and earlier, recipes should be registered in init.

Recipes are now managed by a Forge registry, so IRecipe extends IForgeRegistryEntry and instances of it should be registered in RegistryEvent.Register. As Kokkie said, you should use JSON files wherever possible. You can register your own recipe, ingredient and condition factories to extend the JSON system.

NEI is broken.

Minecraft itself has several models that use overrides, e.g. the compass, bow, elytra and clock; though overrides only apply to item models, not to block models. I don't know of any mods that use the TextureAtlasSprite technique.

See the answers in this thread:

No. You'll need to look at the Forge source code, examples in other mods and forum threads where people have asked similar questions. I explain how to do this here:

Get the Item registry from the ForgeRegistries class, then use IForgeRegistry#getValue to get the Item with the specified registry name. You can then register this Item with the Ore Dictionary.

Create an implementation of IBlockColor that returns the appropriate grass colour based on the biome/season and then register it for Blocks.GRASS (and any other blocks you want to colour) by calling BlockColors#registerBlockColorHandler in init. You can get the BlockColors instance from Minecraft#getBlockColors.

The ItemStack(Item, int, int, NBTTagCompound) constructor doesn't do what you think it does. The NBTTagCompound argument is for the serialised capability data, not the ItemStack's compound tag. Use one of the constructors without an NBTTagCompound argument and then use ItemStack#setTagCompound to set the ItemStack's compound tag. You shouldn't be manually creating the potion NBT anyway. If the effects you want already have a PotionType, use PotionUtils.addPotionToItemStack to add that to the potion ItemStack. If the effects don't have a PotionType (and you don't want to create one for them), use PotionUtils.appendEffects to add them to the potion ItemStack instead. If you want a splash potion, use Items.SPLASH_POTION instead of Items.POTIONITEM.

How does the user log in? Do you launch the official launcher?

You should have the Minecraft and Forge source code available in the forgeSrc-<version> referenced library, so you can either browse to the Chunk class inside of it or use your IDE's Navigate To Class (IDEA, Ctrl+N)/Open Type (Eclipse, Ctrl+Shift+T) feature to open the Chunk class directly.

Use BlockStateContainer.Builder to create the BlockStateContainer, you can call BlockStateContainer.Builder#add once for each array of properties