Method updateTick

src/main/java/net/minecraft/block/BlockPortal.java:35–59

(World worldIn, BlockPos pos, IBlockState state, Random rand)

    }

    public void updateTick(World worldIn, BlockPos pos, IBlockState state, Random rand)
    {
        super.updateTick(worldIn, pos, state, rand);

        if (worldIn.provider.isSurfaceWorld() && worldIn.getGameRules().getGameRuleBooleanValue("doMobSpawning") && rand.nextInt(2000) < worldIn.getDifficulty().getDifficultyId())
        {
            int i = pos.getY();
            BlockPos blockpos;

            for (blockpos = pos; !World.doesBlockHaveSolidTopSurface(worldIn, blockpos) && blockpos.getY() > 0; blockpos = blockpos.down())
            {
                ;
            }

            if (i > 0 && !worldIn.getBlockState(blockpos.up()).getBlock().isNormalCube())
            {
                Entity entity = ItemMonsterPlacer.spawnCreature(worldIn, 57, (double)blockpos.getX() + 0.5D, (double)blockpos.getY() + 1.1D, (double)blockpos.getZ() + 0.5D);

                if (entity != null)
                {
                    entity.timeUntilPortal = entity.getPortalCooldown();
                }
            }
        }
    }

    public AxisAlignedBB getCollisionBoundingBox(World worldIn, BlockPos pos, IBlockState state)
    {