Java 类net.minecraft.block.BlockBanner 实例源码

public static ItemStack getBannerItemFromBlock(World world, BlockPos pos)
{
    IBlockState blockstate = world.getBlockState(pos);
    if (blockstate.getBlock() instanceof BlockBanner) {
        BlockBanner bannerblock = (BlockBanner) blockstate.getBlock();
        return bannerblock.getItem(world, pos, blockstate);
    }
    return ItemStack.EMPTY;
}

private boolean checkSupposedPoweredState()
{
    final ItemStack filter = bannerInventory.getStackInSlot(0);

    IBlockState blockState = world.getBlockState(pos);
    EnumFacing facing = blockState.getValue(BlockBannerDetector.FACING);

    boolean detected = false;
    BlockPos lastPos = null;

    if(!filter.isEmpty() && filter.getItem() instanceof ItemBanner) {
        for (int i = 1; i <= maxdist; i++) {
            BlockPos nextPos = new BlockPos(pos.offset(facing, i));
            lastPos = nextPos;

            if (world.isBlockLoaded(nextPos)) {
                IBlockState nextState = world.getBlockState(nextPos);
                if (nextState.isOpaqueCube()) break;
                detected = checkBanner(nextPos,filter,BlockBanner.class);
                if(!detected) detected = checkBanner(nextPos.up(), filter, BlockBanner.BlockBannerHanging.class);
                if(!detected) detected = checkBanner(nextPos.down(), filter, BlockBanner.BlockBannerStanding.class);

                if(detected) break;
            }
        }

        if (!detected && maxdist > 0) {
            List<Entity> entityList = world.getEntitiesWithinAABB(Entity.class, new AxisAlignedBB(this.pos, lastPos.add(1,1,1)), new Predicate<Entity>() {
                @Override
                public boolean apply(Entity input) {
                    return BannerUtil.isSameBanner(filter, input);
                }
            });
            detected = entityList != null && entityList.size() > 0;
        }
    }

    return detected;
}

private boolean checkBanner(BlockPos pos, ItemStack filter, Class type)
{
    IBlockState state = world.getBlockState(pos);
    if (type.isInstance(state.getBlock())) {
        BlockBanner bannerblock = (BlockBanner) state.getBlock();
        ItemStack banner = bannerblock.getItem(world, pos, state);
        return BannerUtil.isSameBanner(filter,banner);
    }

    return false;
}