    001    package net.minecraft.block;
    002
    003    import java.util.Random;
    004    import net.minecraft.block.material.Material;
    005    import net.minecraft.creativetab.CreativeTabs;
    006    import net.minecraft.entity.item.EntityFallingSand;
    007    import net.minecraft.world.World;
    008
    009    public class BlockSand extends Block
    010    {
    011        /** Do blocks fall instantly to where they stop or do they fall over time */
    012        public static boolean fallInstantly = false;
    013
    014        public BlockSand(int par1, int par2)
    015        {
    016            super(par1, par2, Material.sand);
    017            this.setCreativeTab(CreativeTabs.tabBlock);
    018        }
    019
    020        public BlockSand(int par1, int par2, Material par3Material)
    021        {
    022            super(par1, par2, par3Material);
    023        }
    024
    025        /**
    026         * Called whenever the block is added into the world. Args: world, x, y, z
    027         */
    028        public void onBlockAdded(World par1World, int par2, int par3, int par4)
    029        {
    030            par1World.scheduleBlockUpdate(par2, par3, par4, this.blockID, this.tickRate());
    031        }
    032
    033        /**
    034         * Lets the block know when one of its neighbor changes. Doesn't know which neighbor changed (coordinates passed are
    035         * their own) Args: x, y, z, neighbor blockID
    036         */
    037        public void onNeighborBlockChange(World par1World, int par2, int par3, int par4, int par5)
    038        {
    039            par1World.scheduleBlockUpdate(par2, par3, par4, this.blockID, this.tickRate());
    040        }
    041
    042        /**
    043         * Ticks the block if it's been scheduled
    044         */
    045        public void updateTick(World par1World, int par2, int par3, int par4, Random par5Random)
    046        {
    047            if (!par1World.isRemote)
    048            {
    049                this.tryToFall(par1World, par2, par3, par4);
    050            }
    051        }
    052
    053        /**
    054         * If there is space to fall below will start this block falling
    055         */
    056        private void tryToFall(World par1World, int par2, int par3, int par4)
    057        {
    058            if (canFallBelow(par1World, par2, par3 - 1, par4) && par3 >= 0)
    059            {
    060                byte var8 = 32;
    061
    062                if (!fallInstantly && par1World.checkChunksExist(par2 - var8, par3 - var8, par4 - var8, par2 + var8, par3 + var8, par4 + var8))
    063                {
    064                    if (!par1World.isRemote)
    065                    {
    066                        EntityFallingSand var9 = new EntityFallingSand(par1World, (double)((float)par2 + 0.5F), (double)((float)par3 + 0.5F), (double)((float)par4 + 0.5F), this.blockID, par1World.getBlockMetadata(par2, par3, par4));
    067                        this.onStartFalling(var9);
    068                        par1World.spawnEntityInWorld(var9);
    069                    }
    070                }
    071                else
    072                {
    073                    par1World.setBlockWithNotify(par2, par3, par4, 0);
    074
    075                    while (canFallBelow(par1World, par2, par3 - 1, par4) && par3 > 0)
    076                    {
    077                        --par3;
    078                    }
    079
    080                    if (par3 > 0)
    081                    {
    082                        par1World.setBlockWithNotify(par2, par3, par4, this.blockID);
    083                    }
    084                }
    085            }
    086        }
    087
    088        /**
    089         * Called when the falling block entity for this block is created
    090         */
    091        protected void onStartFalling(EntityFallingSand par1EntityFallingSand) {}
    092
    093        /**
    094         * How many world ticks before ticking
    095         */
    096        public int tickRate()
    097        {
    098            return 5;
    099        }
    100
    101        /**
    102         * Checks to see if the sand can fall into the block below it
    103         */
    104        public static boolean canFallBelow(World par0World, int par1, int par2, int par3)
    105        {
    106            int var4 = par0World.getBlockId(par1, par2, par3);
    107
    108            if (var4 == 0)
    109            {
    110                return true;
    111            }
    112            else if (var4 == Block.fire.blockID)
    113            {
    114                return true;
    115            }
    116            else
    117            {
    118                Material var5 = Block.blocksList[var4].blockMaterial;
    119                return var5 == Material.water ? true : var5 == Material.lava;
    120            }
    121        }
    122
    123        /**
    124         * Called when the falling block entity for this block hits the ground and turns back into a block
    125         */
    126        public void onFinishFalling(World par1World, int par2, int par3, int par4, int par5) {}
    127    }