[1.10.2] Help with getStateFromMeta/getMetaFromState

[DeadSix27]

So I have experience in other languages and a little in Java.

But no experience in Forge / Minecraft modding.

 

And I came to an issue I am unable to solve:

 

I worked mostly of the examples made by https://github.com/TheGreyGhost/MinecraftByExample/

 

I nailed my issue down to the overridden functions getStateFromMeta and getMetaFromState.

 

So the issue is:

 

My code crashes with the following stacktrace:

 

net.minecraftforge.fml.common.LoaderExceptionModCrash: Caught exception from Test (testmod)
Caused by: java.lang.ArrayIndexOutOfBoundsException: 18
at net.minecraftforge.fml.common.registry.GameData$BlockCallbacks.onAdd(GameData.java:303)
at net.minecraftforge.fml.common.registry.GameData$BlockCallbacks.onAdd(GameData.java:284)
at net.minecraftforge.fml.common.registry.FMLControlledNamespacedRegistry.addObjectRaw(FMLControlledNamespacedRegistry.java:584)
at net.minecraftforge.fml.common.registry.FMLControlledNamespacedRegistry.add(FMLControlledNamespacedRegistry.java:482)
at net.minecraftforge.fml.common.registry.FMLControlledNamespacedRegistry.register(FMLControlledNamespacedRegistry.java:829)
at net.minecraftforge.fml.common.registry.GameData.register_impl(GameData.java:254)
at net.minecraftforge.fml.common.registry.GameRegistry.register(GameRegistry.java:153)

at my.testmod.StartupCommon.preInitCommon(StartupCommon.java:27) <---

 

First problem is, the stacktrace is not detailed enough, all it points me to is:

 

GameRegistry.register(testBlockVariant);

 

Is there a way to get more out of the stacktrace in Java/Forge/Minecraft?

 

But I was able to find what is possibly the cause of the crash, its somewhere in the Meta/State functions.

 

Here is the full BlockTestBlockVariants.java

 

https://gist.github.com/DeadSix27/3f508233175d7e5874ce18aa32698053

 

and StartupCommon.java

 

https://gist.github.com/DeadSix27/2997707637f59db7c81d82ee7c7e5159

 

If you need any more information or files, tell me.

 

 

[Animefan8888]

Meta cannot be greater than 15.

[DeadSix27]

So in short the example is wrong?

 

Meaning

 

    @Override
    public int getMetaFromState(IBlockState state)
    {
        EnumFacing facing = (EnumFacing)state.getValue(PROPERTYFACING);
        EnumColour colour = (EnumColour)state.getValue(PROPERTYCOLOUR);

        int facingbits = facing.getHorizontalIndex();
        int colourbits = colour.getMetadata() << 2;
        return facingbits | colourbits;
    }

 

would return a number bigger than 15?

[larsgerrits]

You have 2 properties: one for the horizontal directions (4 directions) and one for the colors, which are right now 7 values, because you commented out the rest. 4*7=28 possible states, which is more than the 16 values metadata can handle (0-15). If you need more than 16 different values, you have to use another way of storing data, most likely a

TileEntity

.

[Animefan8888]

So in short the example is wrong?

 

Meaning

 

    @Override
    public int getMetaFromState(IBlockState state)
    {
        EnumFacing facing = (EnumFacing)state.getValue(PROPERTYFACING);
        EnumColour colour = (EnumColour)state.getValue(PROPERTYCOLOUR);

        int facingbits = facing.getHorizontalIndex();
        int colourbits = colour.getMetadata() << 2;
        return facingbits | colourbits;
    }

 

would return a number bigger than 15?

Yes it would return a bigger value than 15, but the tutorial is not wrong. You used the wrong bit shift "<<" instead of ">>"

[DeadSix27]

I figured it has something to do with that, the whole bit code there is a  little beyond my experience, never worked with bitshifting, I will have to read more into that.

 

EDIT: However I should also look at Tile Entities, I guess, I read about people using the tile data for colour and the state for facing, which would allow for a bigger range of colours too.

[DeadSix27]

Yes it would return a bigger value than 15, but the tutorial is not wrong. You used the wrong bit shift "<<" instead of ">>"

 

What could cause the facing and colour to be wrong upon world load though? I got it working but only until I save and close the world.

 

Then when it loads the world data the states are wrong.

[larsgerrits]

If you are still using more than 16 metadata values, that's probably what's causing the issue. If you want to have 4 facings, and the full 16 colors, you have 64 different states, which metadata can't handle. You should really use a

TileEntity

for this.

[jeffryfisher]

BTW, using a TE will not get you away from states and properties. It only serves to truncate the metadata value stored with a block.

 

Another dodge is if one of your properties can be calculated from looking at neighboring blocks (the way walls connect). If for instance your facing depended on neighboring blocks, then it need not be stored in meta.

 

PS: Does vanilla already have a BlockHorizontal class from which you can subclass?

[DeadSix27]

BTW, using a TE will not get you away from states and properties. It only serves to truncate the metadata value stored with a block.

 

Another dodge is if one of your properties can be calculated from looking at neighboring blocks (the way walls connect). If for instance your facing depended on neighboring blocks, then it need not be stored in meta.

 

PS: Does vanilla already have a BlockHorizontal class from which you can subclass?

 

Unfortunately the neighboring blocks idea doesn't work in my case, as for example, it can be on any of the 3 sides in a corner of 3 blocks.