Best Way to Give Blocks "Health"

[1SDAN]

I would like to add "health" to all blocks in the game, where breaking a block lowers it's "health", drops its drops but does not remove it from the world unless the "health" is now at or lower than zero.

 

I am able to add a event listener to replace the block when broken while still dropping its drops, but I am having trouble figuring out what would be the best method of adding a "health" value to all blocks in the game.

 

What do you suggest I do?

[Draco18s]

All blocks in the game?

You won't be able to do this easily. Add it to your own blocks? Fairly easily. I did this with my own ores.

[Animefan8888]

3 hours ago, 1SDAN said:

What do you suggest I do?

If you are dead set on this idea you will have to create a BlockPos to int Map kinda thing and save it to the world yourself.

[1SDAN]

1 hour ago, Animefan8888 said:

If you are dead set on this idea you will have to create a BlockPos to int Map kinda thing and save it to the world yourself.

Is there no way to store it as a variable within blocks?

3 hours ago, Draco18s said:

All blocks in the game?

You won't be able to do this easily. Add it to your own blocks? Fairly easily. I did this with my own ores.

I assume it's a limitation in Minecraft's implementation of blocks?

Edited August 31, 2018 by 1SDAN

[1SDAN]

1 minute ago, diesieben07 said:

Block objects are singletons, they are more like block types. An actual placed block in the world is represented by a number in a big array, for efficiency. If additional data is required for a location, the block type must explicitly be configured to have a tile entity, this cannot be done for blocks that "are not yours" or after the fact and it comes with performance implications, which is why it is an opt-in thing.

 

You will need to use a capability attached to Chunk to store this additional data.

Thank you very much.

[Animefan8888]

4 hours ago, 1SDAN said:

Is there no way to store it as a variable within blocks?

No, you cannot. 

[1SDAN]

On 8/31/2018 at 5:18 PM, diesieben07 said:

Block objects are singletons, they are more like block types. An actual placed block in the world is represented by a number in a big array, for efficiency. If additional data is required for a location, the block type must explicitly be configured to have a tile entity, this cannot be done for blocks that "are not yours" or after the fact and it comes with performance implications, which is why it is an opt-in thing.

 

You will need to use a capability attached to Chunk to store this additional data.

Am I correct in that this means I will have to create a 3D array in order to store per-block values?

[Animefan8888]

8 minutes ago, 1SDAN said:

Am I correct in that this means I will have to create a 3D array in order to store per-block values?

No, you could create a Map<BlockPos, Float/Integer> which will map a x,y,z to a health value.

[1SDAN]

8 minutes ago, Animefan8888 said:

No, you could create a Map<BlockPos, Float/Integer> which will map a x,y,z to a health value.

If my understanding of Chunk Capabilities (based on the example mod) is correct, I need an IStorage, which requires the use of an NBT tag matching the type of the variable. However there's no NBTTagMap class. Did I do something wrong? Must I make my own?

[Animefan8888]

1 minute ago, 1SDAN said:

Did I do something wrong?

No

 

1 minute ago, 1SDAN said:

Must I make my own?

No, use the default NBT stuff, you can convert the BlockPos to a string and use that as the key for the health value, either by directly changing the xyz to some string and parsing it, or by converting it to a long via BlockPos#toLong and converting that to a string.

[Animefan8888]

5 minutes ago, 1SDAN said:

NBT tag matching the type of the variable

Use an NBTTagCompound or an NBTTagList

[1SDAN]

40 minutes ago, Animefan8888 said:

Use an NBTTagCompound or an NBTTagList

I'm having trouble finding a method of iterating through an NBTTagCompound. It seems like I'm finding this a lot more difficult than it should be. I'm trying to use it in the following code:

public static class QubHealthStorage implements Capability.IStorage<IQubHealth>
    {
        @Nullable
        @Override
        public NBTBase writeNBT(Capability<IQubHealth> capability, IQubHealth instance, EnumFacing side) {
            return new NBTTagInt(instance.get());
        }
        @Override
        public void readNBT(Capability<IQubHealth> capability, IQubHealth instance, EnumFacing side, NBTBase nbt) {
            if (nbt instanceof NBTTagInt)
            {
                // The state is being loaded and not updated. We set the value silently to avoid unnecessary dirty chunks
                instance.set(((NBTTagInt) nbt).getInt(), false);
            }
        }
    }

 

That's the int implementation.

 

This is what I have in my current Map implementation

public static class QubHealthStorage implements Capability.IStorage<IQubHealth>
    {
        @Nullable
        @Override
        public NBTBase writeNBT(Capability<IQubHealth> capability, IQubHealth instance, EnumFacing side) {
            NBTTagCompound compound = new NBTTagCompound();
        	for (Entry<BlockPos, Integer> entry : instance.get().entrySet())
            {
            	compound.setInteger(entry.getKey().toString(), entry.getValue());
            }
            return compound;
        }
        @Override
        public void readNBT(Capability<IQubHealth> capability, IQubHealth instance, EnumFacing side, NBTBase nbt) {
            if (nbt instanceof NBTTagCompound)
            {
            	//iterate through compound and set values
            }
        }
    }

3 minutes ago, diesieben07 said:

I don't recommend using a Map<BlockPos,Float>, especially if you plan on giving this property to a lot of blocks.

Since you are storing positions per chunk (x and z 0 through 15, y 0 through 255), you can easily derive a single short for the position of a block in this chunk:

short uniqueKey = y << 8 | x << 4 | z

Then throw a Short2FloatMap on it and you should have something quite workable.

Seems like it'll end up being a lot less hassle, thanks.

Edited September 3, 2018 by 1SDAN

[Animefan8888]

2 minutes ago, 1SDAN said:

This is what I have in my current Map implementation

NBTTagCompound#getKeySet OR you could use an NBTTagList which may be easier.

Edited September 3, 2018 by Animefan8888

[1SDAN]

27 minutes ago, diesieben07 said:

I don't recommend using a Map<BlockPos,Float>, especially if you plan on giving this property to a lot of blocks.

Since you are storing positions per chunk (x and z 0 through 15, y 0 through 255), you can easily derive a single short for the position of a block in this chunk:

short uniqueKey = y << 8 | x << 4 | z

Then throw a Short2FloatMap on it and you should have something quite workable.

Your comment is a bit vague, are you saying I should use a Map<Short,Int> or a series of Longs/Strings/Shorts that when combined contain 16x256x16 X digit integers?

Edited September 3, 2018 by 1SDAN

[Animefan8888]

8 minutes ago, 1SDAN said:

Your comment is a bit vague, are you saying I should use a Map<Short,Int> or a series of Longs/Strings/Shorts that when combined contain 16x256x16 X digit integers?

He means a Map<Short, Float/Integer>

[1SDAN]

I just noticed I typed String instead of Integer. (Short/String/Long instead of Short/Integer/Long)...

 

*faceplam*

[jabelar]

As diesieben07 is pointing out, performance is key for such an implementation. You need to understand the performance implications of the various collections and the iterations thereof.

 

One thing that might help performance -- I think you probably only need to store information on blocks that have been interacted with. So potentially your map could be a lot smaller than containing all blockpos positions in the chunk, with the assumption that any block not in the map is full health. 

[1SDAN]

3 hours ago, jabelar said:

As diesieben07 is pointing out, performance is key for such an implementation. You need to understand the performance implications of the various collections and the iterations thereof.

 

One thing that might help performance -- I think you probably only need to store information on blocks that have been interacted with. So potentially your map could be a lot smaller than containing all blockpos positions in the chunk, with the assumption that any block not in the map is full health. 

Funny enough, this is the exact implementation I went with.

4 hours ago, diesieben07 said:

No, I specifically mean to use the Fastutil one, which will not incur the boxing overhead.

Since starting this thread I've moved from Short, Integer maps to Short, Integer[] maps, does fastutil support something like this? I'm looking at the shorts package and can't find anything of the like.

Edited September 4, 2018 by 1SDAN

[1SDAN]

2 minutes ago, diesieben07 said:

Never, ever use Integer[], it's terrible. Use int[]. int[] is just an Object, so you can use Short2ReferenceMap<int[]>.

Understood. I would normally have used int[] but animefan advised using Float or Integer so I was misled to thinking it'd be better.