update block please!

    public boolean onBlockActivated(World world, int x, int y, int z, EntityPlayer player, int side, float faceX, float faceY, float faceZ)
    {
        if (!world.isRemote && player.getHeldItem() == null && !player.isSneaking())
        {
            Logger.Info(String.format("onBlockActivated (%d,%d,%d)", x, y, z));
            //world.setBlockMetadataWithNotify(x, y, z, 1, 3);
            //this.setLightLevel(15);

            TileEntity te = world.getTileEntity(x,y,z);

            if (te instanceof TileEntityScreen)
            {
                TileEntityScreen screen = (TileEntityScreen)te;
                float fDepth = screen.Depth;

                fDepth = fDepth-0.1f < 0.1f ? 1.0f : fDepth-0.1f;

                screen.Depth = fDepth;
                setBlockBoundsBasedOnState(world, x, y, z);
                world.markBlockForUpdate(x, y, z);
            }

            return true;
        }
        else
            return false;
    }