[1.11.X] Compass to point to your personal spawn point

[gibraltar]

I've written a compass that I believe should point to your personal spawn point, if it's been set. It looks a lot like the regular compass code, but instead of pointing to world spawn it gets the bed location for the current user and points to that. The issue I'm seeing is that when I sleep in a new place, the compass doesn't start pointing to the new location. But I've checked that the player's spawn is changing, and the same method, getBedLocation returns a different value when called within other events, so I'm not sure what the problem is. Any help would be appreciated.

 

public class ItemPersonalCompass extends Item {
    public ItemPersonalCompass() {
        addPropertyOverride(new ResourceLocation("angle"), new IItemPropertyGetter() {
            @SideOnly(Side.CLIENT)
            double rotation;
            @SideOnly(Side.CLIENT)
            double rota;
            @SideOnly(Side.CLIENT)
            long lastUpdateTick;

            @SideOnly(Side.CLIENT)
            public float apply(ItemStack stack, @Nullable World worldIn, @Nullable EntityLivingBase entityIn) {
                if (entityIn == null && !stack.isOnItemFrame()) {
                    return 0.0F;
                }
                else {
                    boolean flag = entityIn != null;
                    Entity entity = flag ? entityIn : stack.getItemFrame();

                    if (worldIn == null) {
                        worldIn = entity.worldObj;
                    }

                    BlockPos destinationPos = new BlockPos(0, 0, 0);
                    if (entity instanceof EntityPlayer) {
                        destinationPos = ((EntityPlayer) entity).getBedLocation(0);
                        if (destinationPos == null) {
                            return 0;
                        }
                    }
                    else {
                        return 0F;
                    }

                    double d0;

                    if (destinationPos != null) {
                        double d1 = flag ? (double) entity.rotationYaw : getFrameRotation((EntityItemFrame) entity);
                        d1 = d1 % 360.0D;
                        double d2 = getPosToAngle(worldIn, entity, destinationPos);
                        d0 = Math.PI - ((d1 - 90.0D) * 0.01745329238474369D - d2);
                    } else {
                        d0 = Math.random() * (Math.PI * 2D);
                    }

                    if (flag) {
                        d0 = wobble(worldIn, d0);
                    }

                    float f = (float) (d0 / (Math.PI * 2D));
                    return MathHelper.positiveModulo(f, 1.0F);
                }
            }

            @SideOnly(Side.CLIENT)
            private double wobble(World p_185093_1_, double p_185093_2_) {
                if (p_185093_1_.getTotalWorldTime() != lastUpdateTick) {
                    lastUpdateTick = p_185093_1_.getTotalWorldTime();
                    double d0 = p_185093_2_ - rotation;
                    d0 = d0 % (Math.PI * 2D);
                    d0 = MathHelper.clamp_double(d0, -1.0D, 1.0D);
                    rota += d0 * 0.1D;
                    rota *= 0.8D;
                    rotation += rota;
                }

                return rotation;
            }

            @SideOnly(Side.CLIENT)
            private double getFrameRotation(EntityItemFrame itemFrame) {
                return (double) MathHelper.clampAngle(180 + itemFrame.facingDirection.getHorizontalIndex() * 90);
            }

            @SideOnly(Side.CLIENT)
            private double getPosToAngle(World world, Entity entity, BlockPos blockpos) {
                return Math.atan2((double) blockpos.getZ() - entity.posZ, (double) blockpos.getX() - entity.posX);
            }
        });

        setUnlocalizedName("compass_personal");
        setCreativeTab(CreativeTabs.TOOLS);
        setRegistryName(Reference.MOD_PREFIX + "compass_personal");

        GameRegistry.register(this);
        GameRegistry.addRecipe(new ItemStack(this), " I ", "IRI", " I ", 'I', Items.IRON_INGOT, 'R', Items.REDSTONE);
        ModelLoader.setCustomModelResourceLocation(this, 0, new ModelResourceLocation("iberia:compass_personal", "inventory"));
    }
}

[Animefan8888]

It is because you are using the IItemPropertyGetter inside your constructor, so the players spawn point wont change, because the constructor is only called once.

[Draco18s]

It is because you are using the IItemPropertyGetter inside your constructor, so the players spawn point wont change, because the constructor is only called once.

 

This is literally gibberish. The IItemPropertyGetter interface sets up a callback method which is invoked when the item is rendered, all the time, every time.

 

Unless you somehow think that during preInit (before! The title screen) there is a player object and a world to look at...

[gibraltar]

Right, I'm setting up the IItemPropertyGetter the same way it is set up in the vanilla compass class, so I feel good about that. But I think there must be some difference between the EntityPlayer being passed into the apply method and the EntityPlayer being passed to the PlayerSetSpawn event

[gibraltar]

Ok, here's my current theory, after further investigation. The EntityPlayer that gets passed to the IItemPropertyGetter.apply is an AbstractClientPlayer and thus on the client side. I believe that EntityPlayer never has it's spawnChunk field updated when the player's spawn is set (that happens on the server), and the EntityPlayer object on the server side that does have it's spawnChunk set is never communicating that information to the client side.

 

So it appears I need some way, given an AbstractClientPlayer, to ask the server for that player's bed location / spawnChunk. Once that's in place, I'll need a way of caching that info on the client side associated with the AbstractClientPlayer so I'm not asking for it every time we render a compass. I'll be investigating how to do that next, but any tips/pointers to get me started would be awesome.

[Draco18s]

Packets, basically.  The client asks the server "hey, were's my bed?" when it logs in.

When asked, or when the bed is set, the server sends that client the information.

 

You don't need to do anything with the AbstractClientPlayer because when the client asks the server, the server already knows which non-abstract player is asking (due to the message context).