mc-1.12.2/client/src/main/java/net/minecraft/block/BlockBush.java

package net.minecraft.block;

import java.util.Random;
import javax.annotation.Nullable;
import net.minecraft.block.material.MapColor;
import net.minecraft.block.material.Material;
import net.minecraft.block.state.BlockFaceShape;
import net.minecraft.block.state.IBlockState;
import net.minecraft.creativetab.CreativeTabs;
import net.minecraft.init.Blocks;
import net.minecraft.util.BlockRenderLayer;
import net.minecraft.util.EnumFacing;
import net.minecraft.util.math.AxisAlignedBB;
import net.minecraft.util.math.BlockPos;
import net.minecraft.world.IBlockAccess;
import net.minecraft.world.World;

public class BlockBush extends Block
{
    protected static final AxisAlignedBB BUSH_AABB = new AxisAlignedBB(0.30000001192092896D, 0.0D, 0.30000001192092896D, 0.699999988079071D, 0.6000000238418579D, 0.699999988079071D);

    protected BlockBush()
    {
        this(Material.PLANTS);
    }

    protected BlockBush(Material materialIn)
    {
        this(materialIn, materialIn.getMaterialMapColor());
    }

    protected BlockBush(Material materialIn, MapColor mapColorIn)
    {
        super(materialIn, mapColorIn);
        this.setTickRandomly(true);
        this.setCreativeTab(CreativeTabs.DECORATIONS);
    }

    /**
     * Checks if this block can be placed exactly at the given position.
     */
    public boolean canPlaceBlockAt(World worldIn, BlockPos pos)
    {
        return super.canPlaceBlockAt(worldIn, pos) && this.canSustainBush(worldIn.getBlockState(pos.down()));
    }

    /**
     * Return true if the block can sustain a Bush
     */
    protected boolean canSustainBush(IBlockState state)
    {
        return state.getBlock() == Blocks.GRASS || state.getBlock() == Blocks.DIRT || state.getBlock() == Blocks.FARMLAND;
    }

    /**
     * Called when a neighboring block was changed and marks that this state should perform any checks during a neighbor
     * change. Cases may include when redstone power is updated, cactus blocks popping off due to a neighboring solid
     * block, etc.
     */
    public void neighborChanged(IBlockState state, World worldIn, BlockPos pos, Block blockIn, BlockPos fromPos)
    {
        super.neighborChanged(state, worldIn, pos, blockIn, fromPos);
        this.checkAndDropBlock(worldIn, pos, state);
    }

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

    protected void checkAndDropBlock(World worldIn, BlockPos pos, IBlockState state)
    {
        if (!this.canBlockStay(worldIn, pos, state))
        {
            this.dropBlockAsItem(worldIn, pos, state, 0);
            worldIn.setBlockState(pos, Blocks.AIR.getDefaultState(), 3);
        }
    }

    public boolean canBlockStay(World worldIn, BlockPos pos, IBlockState state)
    {
        return this.canSustainBush(worldIn.getBlockState(pos.down()));
    }

    /**
     * @deprecated call via {@link IBlockState#getBoundingBox(IBlockAccess,BlockPos)} whenever possible.
     * Implementing/overriding is fine.
     */
    public AxisAlignedBB getBoundingBox(IBlockState state, IBlockAccess source, BlockPos pos)
    {
        return BUSH_AABB;
    }

    @Nullable

    /**
     * @deprecated call via {@link IBlockState#getCollisionBoundingBox(IBlockAccess,BlockPos)} whenever possible.
     * Implementing/overriding is fine.
     */
    public AxisAlignedBB getCollisionBoundingBox(IBlockState blockState, IBlockAccess worldIn, BlockPos pos)
    {
        return NULL_AABB;
    }

    /**
     * Used to determine ambient occlusion and culling when rebuilding chunks for render
     * @deprecated call via {@link IBlockState#isOpaqueCube()} whenever possible. Implementing/overriding is fine.
     */
    public boolean isOpaqueCube(IBlockState state)
    {
        return false;
    }

    /**
     * @deprecated call via {@link IBlockState#isFullCube()} whenever possible. Implementing/overriding is fine.
     */
    public boolean isFullCube(IBlockState state)
    {
        return false;
    }

    /**
     * Gets the render layer this block will render on. SOLID for solid blocks, CUTOUT or CUTOUT_MIPPED for on-off
     * transparency (glass, reeds), TRANSLUCENT for fully blended transparency (stained glass)
     */
    public BlockRenderLayer getBlockLayer()
    {
        return BlockRenderLayer.CUTOUT;
    }

    /**
     * Get the geometry of the queried face at the given position and state. This is used to decide whether things like
     * buttons are allowed to be placed on the face, or how glass panes connect to the face, among other things.
     * <p>
     * Common values are {@code SOLID}, which is the default, and {@code UNDEFINED}, which represents something that
     * does not fit the other descriptions and will generally cause other things not to connect to the face.

     * @return an approximation of the form of the given face
     * @deprecated call via {@link IBlockState#getBlockFaceShape(IBlockAccess,BlockPos,EnumFacing)} whenever possible.
     * Implementing/overriding is fine.
     */
    public BlockFaceShape getBlockFaceShape(IBlockAccess worldIn, IBlockState state, BlockPos pos, EnumFacing face)
    {
        return BlockFaceShape.UNDEFINED;
    }
}