[1.8.0] [Solved] Metadata Slabs

[Eractnod]

It has taken a few days to finally get my meta data version of slabs to work in 1.8.0.  However, when I place the slabs as a half block all is fine, but when I place as a double slab, they all revert to the setDefautState enumtype.  In my case TELVARITE_COBBLE.  When you break the block, you get two telvarite cobble half slabs, so it is not a texture issue.  If I change the default enumtype to AMATITE_COBBLE, then all double slabs are of that type.  I am not sure if it is a registration problem as the block used to find the iblockstate is always null.

 

Any help would be greatly appreciated.

 

Declaration and registration

//Slabs
public static BlockTEStoneSlab te_stone_slab;
public static BlockTEStoneSlab te_stone_slab_double;

te_stone_slab = new BlockTEStoneSlab(Material.rock, "slabStoneS", 2.0f, 15.0f);
	te_stone_slab_double = new BlockTEStoneSlabDouble(Material.rock, "slabStoneD", 2.0f, 15.0f);
	registerSlab("te_stone_slab", "te_stone_slab_double", te_stone_slab, te_stone_slab_double);

public static void registerSlab(String name, String name2, Block one, Block two){
	GameRegistry.registerBlock(two, ItemBlockModTEStoneSlab.class, name2, new Object[]{one, two});
	GameRegistry.registerBlock(one, ItemBlockModTEStoneSlab.class, name, new Object[]{one, two});
        blockList.add(name);
}

 

Itemblock class

package com.eractnod.telvarianexpanse.itemblocks;


import com.eractnod.telvarianexpanse.blocks.BlockTEStoneSlab;
import com.eractnod.telvarianexpanse.blocks.BlockTEStoneSlabDouble;

import net.minecraft.block.Block;
import net.minecraft.block.BlockSlab;
import net.minecraft.block.state.IBlockState;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.item.ItemBlock;
import net.minecraft.item.ItemSlab;
import net.minecraft.item.ItemStack;
import net.minecraft.util.BlockPos;
import net.minecraft.util.EnumFacing;
import net.minecraft.world.World;
import net.minecraftforge.fml.relauncher.Side;
import net.minecraftforge.fml.relauncher.SideOnly;

public class ItemBlockModTEStoneSlab extends ItemBlock{

private final BlockSlab single;
    private final BlockSlab twoOf;

public ItemBlockModTEStoneSlab(Block block, BlockTEStoneSlab single, BlockTEStoneSlabDouble twoOf) {
	super(block);
       this.single = single;
       this.twoOf = twoOf;
       this.setMaxDamage(0);
       this.setHasSubtypes(true);
    }

    /**
     * Converts the given ItemStack damage value into a metadata value to be placed in the world when this Item is
     * placed as a Block (mostly used with ItemBlocks).
     */
    public int getMetadata(int damage)
    {
        return damage;
    }

    /**
     * Returns the unlocalized name of this item. This version accepts an ItemStack so different stacks can have
     * different names based on their damage or NBT.
     */
    public String getUnlocalizedName(ItemStack stack)
    {
        return this.single.getFullSlabName(stack.getMetadata());
    }

    /**
     * Called when a Block is right-clicked with this Item
     *  
     * @param pos The block being right-clicked
     * @param side The side being right-clicked
     */
    public boolean onItemUse(ItemStack stack, EntityPlayer playerIn, World worldIn, BlockPos pos, EnumFacing side, float hitX, float hitY, float hitZ)
    {
        if (stack.stackSize == 0)
        {
            return false;
        }
        else if (!playerIn.func_175151_a(pos.offset(side), side, stack))
        {
            return false;
        }
        else
        {
            Object object = this.single.func_176553_a(stack);
            IBlockState iblockstate = worldIn.getBlockState(pos);

            if (iblockstate.getBlock() == this.single)
            {
                BlockSlab.EnumBlockHalf enumblockhalf = (BlockSlab.EnumBlockHalf)iblockstate.getValue(BlockSlab.HALF_PROP);

                if ((side == EnumFacing.UP && enumblockhalf == BlockSlab.EnumBlockHalf.BOTTOM || side == EnumFacing.DOWN && enumblockhalf == BlockSlab.EnumBlockHalf.TOP))
                {
                    IBlockState iblockstate1 = this.twoOf.getDefaultState();

                    if (worldIn.checkNoEntityCollision(this.twoOf.getCollisionBoundingBox(worldIn, pos, iblockstate1)) && worldIn.setBlockState(pos, iblockstate1, 3))
                    {
                        worldIn.playSoundEffect((double)((float)pos.getX() + 0.5F), (double)((float)pos.getY() + 0.5F), (double)((float)pos.getZ() + 0.5F), this.twoOf.stepSound.getPlaceSound(), (this.twoOf.stepSound.getVolume() + 1.0F) / 2.0F, this.twoOf.stepSound.getFrequency() * 0.8F);
                        --stack.stackSize;
                    }

                    return true;
                }
            }

            return this.placeDouble(stack, worldIn, pos.offset(side), object) ? true : super.onItemUse(stack, playerIn, worldIn, pos, side, hitX, hitY, hitZ);
        }
    }

    @SideOnly(Side.CLIENT)
    public boolean canPlaceBlockOnSide(World worldIn, BlockPos pos, EnumFacing facing, EntityPlayer player, ItemStack stack)
    {
        BlockPos blockpos1 = pos;
        Object object = this.single.func_176553_a(stack);
        IBlockState iblockstate = worldIn.getBlockState(pos);

        if (iblockstate.getBlock() == this.single)
        {
            boolean flag = iblockstate.getValue(BlockSlab.HALF_PROP) == BlockSlab.EnumBlockHalf.TOP;

            if ((facing == EnumFacing.UP && !flag || facing == EnumFacing.DOWN && flag))
            {
                return true;
            }
        }

        pos = pos.offset(facing);
        IBlockState iblockstate1 = worldIn.getBlockState(pos);
        return iblockstate1.getBlock() == this.single ? true : super.canPlaceBlockOnSide(worldIn, blockpos1, facing, player, stack);
    }

    private boolean placeDouble(ItemStack stack, World worldIn, BlockPos pos, Object obj)
    {
        IBlockState iblockstate = worldIn.getBlockState(pos);

        if (iblockstate.getBlock() == this.single)
        {
                IBlockState iblockstate1 = this.twoOf.getDefaultState();

                if (worldIn.checkNoEntityCollision(this.twoOf.getCollisionBoundingBox(worldIn, pos, iblockstate1)) && worldIn.setBlockState(pos, iblockstate1, 3))
                {
                    worldIn.playSoundEffect((double)((float)pos.getX() + 0.5F), (double)((float)pos.getY() + 0.5F), (double)((float)pos.getZ() + 0.5F), this.twoOf.stepSound.getPlaceSound(), (this.twoOf.stepSound.getVolume() + 1.0F) / 2.0F, this.twoOf.stepSound.getFrequency() * 0.8F);
                    --stack.stackSize;
                }

                return true;
        }

        return false;
    }
}

 

Slab block class

package com.eractnod.telvarianexpanse.blocks;

import java.util.List;
import java.util.Random;

import net.minecraft.block.Block;
import net.minecraft.block.BlockSlab;
import net.minecraft.block.BlockStoneSlab;
import net.minecraft.block.material.Material;
import net.minecraft.block.properties.IProperty;
import net.minecraft.block.properties.PropertyBool;
import net.minecraft.block.properties.PropertyEnum;
import net.minecraft.block.state.BlockState;
import net.minecraft.block.state.IBlockState;
import net.minecraft.creativetab.CreativeTabs;
import net.minecraft.init.Blocks;
import net.minecraft.item.Item;
import net.minecraft.item.ItemStack;
import net.minecraft.util.BlockPos;
import net.minecraft.util.IStringSerializable;
import net.minecraft.world.World;
import net.minecraftforge.fml.relauncher.Side;
import net.minecraftforge.fml.relauncher.SideOnly;

public class BlockTEStoneSlab extends BlockSlab
{
    public static final PropertyBool seamlessBool = PropertyBool.create("seamless");
    public static final PropertyEnum typeVar = PropertyEnum.create("variant", BlockTEStoneSlab.EnumType.class);

    public BlockTEStoneSlab(Material mat, String name, float hardness, float resistance)
    {
        super(Material.rock);
        IBlockState iblockstate = this.blockState.getBaseState();
        if (this.isDouble())
        {
            iblockstate = iblockstate.withProperty(seamlessBool, Boolean.valueOf(false));
        }
        else
        {
            iblockstate = iblockstate.withProperty(HALF_PROP, BlockSlab.EnumBlockHalf.BOTTOM);
        }
        this.setDefaultState(iblockstate.withProperty(typeVar, BlockTEStoneSlab.EnumType.TELVARITE_COBBLE));
        this.setCreativeTab(CreativeTabs.tabBlock);
        this.setHardness(hardness);
        this.setResistance(resistance);
    }

    public Item getItemDropped(IBlockState state, Random rand, int fortune)
    {
        return Item.getItemFromBlock(TEBlocks.te_stone_slab);
    }

    @SideOnly(Side.CLIENT)
    public Item getItem(World worldIn, BlockPos pos)
    {
    	
        return Item.getItemFromBlock(TEBlocks.te_stone_slab);
    }

    public String getFullSlabName(int meta)
    {
        return super.getUnlocalizedName() + "." + BlockTEStoneSlab.EnumType.func_176625_a(meta).func_176627_c();
    }

    public IProperty func_176551_l()
    {
        return typeVar;
    }

    public Object func_176553_a(ItemStack stack)
    {
        return BlockTEStoneSlab.EnumType.func_176625_a(stack.getMetadata() & 7);
    }

    @SideOnly(Side.CLIENT)
    public void getSubBlocks(Item itemIn, CreativeTabs tab, List list)
    {
        if (itemIn != Item.getItemFromBlock(TEBlocks.te_stone_slab_double))
        {
            BlockTEStoneSlab.EnumType[] aenumtype = BlockTEStoneSlab.EnumType.values();
            int i = aenumtype.length;

            for (int j = 0; j < i; ++j)
            {
                BlockTEStoneSlab.EnumType enumtype = aenumtype[j];

                    list.add(new ItemStack(itemIn, 1, enumtype.func_176624_a()));
               
            }
        }
    }

    public IBlockState getStateFromMeta(int meta)
    {
        IBlockState iblockstate = this.getDefaultState().withProperty(typeVar, BlockTEStoneSlab.EnumType.func_176625_a(meta & 7));

        if (this.isDouble())
        {
            iblockstate = iblockstate.withProperty(seamlessBool, Boolean.valueOf((meta &  != 0));
        }
        else
        {
            iblockstate = iblockstate.withProperty(HALF_PROP, (meta &  == 0 ? BlockSlab.EnumBlockHalf.BOTTOM : BlockSlab.EnumBlockHalf.TOP);
        }

        return iblockstate;
    }

    public int getMetaFromState(IBlockState state)
    {
        byte b0 = 0;
        int i = b0 | ((BlockTEStoneSlab.EnumType)state.getValue(typeVar)).func_176624_a();

        if (this.isDouble())
        {
            if (((Boolean)state.getValue(seamlessBool)).booleanValue())
            {
                i |= 8;
            }
        }
        else if (state.getValue(HALF_PROP) == BlockSlab.EnumBlockHalf.TOP)
        {
            i |= 8;
        }

        return i;
    }

    protected BlockState createBlockState()
    {
        return this.isDouble() ? new BlockState(this, new IProperty[] {seamlessBool, typeVar}): new BlockState(this, new IProperty[] {HALF_PROP, typeVar});
    }

    public int damageDropped(IBlockState state)
    {
        return ((BlockTEStoneSlab.EnumType)state.getValue(typeVar)).func_176624_a();
    }

    public static enum EnumType implements IStringSerializable
    {
    	TELVARITE_COBBLE(0, "te_stone_slab", "telvarite_cobble"),
        AMATITE_COBBLE(1, "amatite_te_stone_slab", "amatite_cobble"),
        VARIANITE_COBBLE(2, "varianite_te_stone_slab", "varianite_cobble"),
        ORAMIRITE_COBBLE(3, "oramirite_te_stone_slab", "oramirite_cobble"),
        TELVARITE_BRICK(4, "telvarite_brick_te_stone_slab", "telvarite_brick"),
        AMATITE_BRICK(5, "amatite_brick_te_stone_slab", "amatite_brick"),
        VARIANITE_BRICK(6, "varianite_brick_te_stone_slab", "varianite_brick"),
        ORAMIRITE_BRICK(7, "oramirite_brick_te_stone_slab", "oramirite_brick");

        private static final BlockTEStoneSlab.EnumType[] field_176640_i = new BlockTEStoneSlab.EnumType[values().length];
        private final int meta;
        private final String variantName;
        private final String name;


        private EnumType(int meta, String name)
        {
            this(meta, name, name);
        }

        private EnumType(int meta, String variantName, String name)
        {
            this.meta = meta;
            this.variantName = variantName;
            this.name = name;
        }

        public int func_176624_a()
        {
            return this.meta;
        }

        public String toString()
        {
            return this.variantName;
        }

        public static BlockTEStoneSlab.EnumType func_176625_a(int meta)
        {
            if (meta < 0 || meta >= field_176640_i.length)
            {
                meta = 0;
            }

            return field_176640_i[meta];
        }

        public String getName()
        {
            return this.variantName;
        }

        public String func_176627_c()
        {
            return this.name;
        }

        static
        {
            BlockTEStoneSlab.EnumType[] var0 = values();
            int var1 = var0.length;

            for (int var2 = 0; var2 < var1; ++var2)
            {
                BlockTEStoneSlab.EnumType var3 = var0[var2];
                field_176640_i[var3.func_176624_a()] = var3;
            }
        }
    }

@Override
public boolean isDouble() {
	return false;
}

}

 

Double slab block class

package com.eractnod.telvarianexpanse.blocks;

import net.minecraft.block.Block;
import net.minecraft.block.material.Material;
import net.minecraft.block.properties.IProperty;
import net.minecraft.init.Blocks;
import net.minecraft.item.Item;
import net.minecraft.util.BlockPos;
import net.minecraft.world.World;
import net.minecraftforge.fml.relauncher.Side;
import net.minecraftforge.fml.relauncher.SideOnly;

public class BlockTEStoneSlabDouble extends BlockTEStoneSlab{

public BlockTEStoneSlabDouble(Material mat, String name, float hardness, float resistance) {
	super(mat, name, hardness, resistance);
	setCreativeTab(null);
}

@Override
public boolean isDouble(){
	return true;
}


}

 

Client Proxy

package com.eractnod.telvarianexpanse.client;

import com.eractnod.telvarianexpanse.TelvarianExpanse;
import com.eractnod.telvarianexpanse.blocks.TEBlocks;
import com.eractnod.telvarianexpanse.items.TEItems;
import com.eractnod.telvarianexpanse.lamps.TileEntityChandelier;
import com.eractnod.telvarianexpanse.lamps.TileEntityChandelierRenderer;
import com.eractnod.telvarianexpanse.lamps.TileEntityFloorLamp;
import com.eractnod.telvarianexpanse.lamps.TileEntityFloorLampRenderer;
import com.eractnod.telvarianexpanse.lamps.TileEntityStreetLamp;
import com.eractnod.telvarianexpanse.lamps.TileEntityStreetLampRenderer;
import com.eractnod.telvarianexpanse.machines.TEMachines;

import net.minecraft.block.Block;
import net.minecraft.client.Minecraft;
import net.minecraft.client.renderer.ItemModelMesher;
import net.minecraft.client.resources.model.ModelBakery;
import net.minecraft.client.resources.model.ModelResourceLocation;
import net.minecraft.item.Item;
import net.minecraftforge.fml.client.registry.ClientRegistry;
import net.minecraftforge.fml.common.registry.GameRegistry;
import net.minecraftforge.fml.relauncher.Side;
import net.minecraftforge.fml.relauncher.SideOnly;


@SideOnly(Side.CLIENT)
public class ClientProxy {

public static void init(){

	for(String name : TEItems.itemList){
		System.out.println("real item&&&&&&&&&&&&&&&&&&& " + name);
	    registerItem(GameRegistry.findItem(TelvarianExpanse.MODID, name), TelvarianExpanse.MODID + ":" + name);
	}

	for(String name : TEBlocks.blockList){
		Item i = GameRegistry.findItem(TelvarianExpanse.MODID, name);
		System.out.println("Item********************* " + name);
		registerItem(i, TelvarianExpanse.MODID + ":" + name);
	}

	for(String name : TEMachines.machineList){
		Item i = GameRegistry.findItem(TelvarianExpanse.MODID, name);
		System.out.println("Item********************* " + name);
		registerItem(i, TelvarianExpanse.MODID + ":" + name);
	}




	Item te_stone_slab = GameRegistry.findItem(TelvarianExpanse.MODID, "te_stone_slab");
	registerItem(te_stone_slab, 0, TelvarianExpanse.MODID + ":te_stone_slab");
	registerItem(te_stone_slab, 1, TelvarianExpanse.MODID + ":amatite_te_stone_slab");
	registerItem(te_stone_slab, 2, TelvarianExpanse.MODID + ":varianite_te_stone_slab");
	registerItem(te_stone_slab, 3, TelvarianExpanse.MODID + ":oramirite_te_stone_slab");
	registerItem(te_stone_slab, 4, TelvarianExpanse.MODID + ":telvarite_brick_te_stone_slab");
	registerItem(te_stone_slab, 5, TelvarianExpanse.MODID + ":amatite_brick_te_stone_slab");
	registerItem(te_stone_slab, 6, TelvarianExpanse.MODID + ":varianite_brick_te_stone_slab");
	registerItem(te_stone_slab, 7, TelvarianExpanse.MODID + ":oramirite_brick_te_stone_slab");


	Item te_stone_slab_double = GameRegistry.findItem(TelvarianExpanse.MODID, "te_stone_slab_double");
	registerItem(te_stone_slab_double, 0, TelvarianExpanse.MODID + ":te_stone_slab_double");
	registerItem(te_stone_slab_double, 1, TelvarianExpanse.MODID + ":amatite_te_stone_slab_double");
	registerItem(te_stone_slab_double, 2, TelvarianExpanse.MODID + ":varianite_te_stone_slab_double");
	registerItem(te_stone_slab_double, 3, TelvarianExpanse.MODID + ":oramirite_te_stone_slab_double");
	registerItem(te_stone_slab_double, 4, TelvarianExpanse.MODID + ":telvarite_brick_te_stone_slab_double");
	registerItem(te_stone_slab_double, 5, TelvarianExpanse.MODID + ":amatite_brick_te_stone_slab_double");
	registerItem(te_stone_slab_double, 6, TelvarianExpanse.MODID + ":varianite_brick_te_stone_slab_double");
	registerItem(te_stone_slab_double, 7, TelvarianExpanse.MODID + ":oramirite_brick_te_stone_slab_double");




}

public static void preInit(){
	ModelBakery.addVariantName(Item.getItemFromBlock(TEBlocks.te_stone_slab), new String[]{TelvarianExpanse.MODID + ":te_stone_slab", TelvarianExpanse.MODID + ":amatite_te_stone_slab", TelvarianExpanse.MODID + ":varianite_te_stone_slab", TelvarianExpanse.MODID + ":oramirite_te_stone_slab", TelvarianExpanse.MODID + ":telvarite_brick_te_stone_slab", TelvarianExpanse.MODID + ":amatite_brick_te_stone_slab", TelvarianExpanse.MODID + ":varianite_brick_te_stone_slab", TelvarianExpanse.MODID + ":oramirite_brick_te_stone_slab"});


}

public static void registerItem(Item item, int metadata, String itemName)
    {
        ItemModelMesher mesher = Minecraft.getMinecraft().getRenderItem().getItemModelMesher();
        mesher.register(item, metadata, new ModelResourceLocation(itemName, "inventory"));
    }

    public static void registerBlock(Block block, int metadata, String blockName)
    {
        registerItem(Item.getItemFromBlock(block), metadata, blockName);
    }

    public static void registerBlock(Block block, String blockName)
    {
        registerBlock(block, 0, blockName);
    }

    public static void registerItem(Item item, String itemName)
    {
        registerItem(item, 0, itemName);
    }
}

[Eractnod]

As always, the issue turned out to be me.  I was using my single slab Itemblock which defaults to the default blockstate.  Made changes to the Itemblock class, and now doubles are placing correctly.  Code listed below.

 

ItemBlock

package com.eractnod.telvarianexpanse.itemblocks;


import com.eractnod.telvarianexpanse.blocks.BlockTEStoneSlab;
import com.eractnod.telvarianexpanse.blocks.BlockTEStoneSlabDouble;

import net.minecraft.block.Block;
import net.minecraft.block.BlockSlab;
import net.minecraft.block.properties.IProperty;
import net.minecraft.block.state.IBlockState;
import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.item.ItemBlock;
import net.minecraft.item.ItemSlab;
import net.minecraft.item.ItemStack;
import net.minecraft.util.BlockPos;
import net.minecraft.util.EnumFacing;
import net.minecraft.world.World;
import net.minecraftforge.fml.relauncher.Side;
import net.minecraftforge.fml.relauncher.SideOnly;

public class ItemBlockModTEStoneSlab extends ItemBlock{

private final BlockSlab single;
    private final BlockSlab twoOf;

public ItemBlockModTEStoneSlab(Block block, BlockTEStoneSlab single, BlockTEStoneSlabDouble twoOf) {
	super(block);
       this.single = single;
       this.twoOf = twoOf;
       this.setMaxDamage(0);
       this.setHasSubtypes(true);
    }

    /**
     * Converts the given ItemStack damage value into a metadata value to be placed in the world when this Item is
     * placed as a Block (mostly used with ItemBlocks).
     */
    public int getMetadata(int damage)
    {
        return damage;
    }

    /**
     * Returns the unlocalized name of this item. This version accepts an ItemStack so different stacks can have
     * different names based on their damage or NBT.
     */
    public String getUnlocalizedName(ItemStack stack)
    {
        return this.single.getFullSlabName(stack.getMetadata());
    }

    /**
     * Called when a Block is right-clicked with this Item
     *  
     * @param pos The block being right-clicked
     * @param side The side being right-clicked
     */
    public boolean onItemUse(ItemStack stack, EntityPlayer playerIn, World worldIn, BlockPos pos, EnumFacing side, float hitX, float hitY, float hitZ)
    {
        if (stack.stackSize == 0)
        {
            return false;
        }
        else if (!playerIn.func_175151_a(pos.offset(side), side, stack))
        {
            return false;
        }
        else
        {
            Object object = this.single.func_176553_a(stack);
            IBlockState iblockstate = worldIn.getBlockState(pos);

            if (iblockstate.getBlock() == this.single)
            {
                IProperty iproperty = this.single.func_176551_l();
                Comparable comparable = iblockstate.getValue(iproperty);
                BlockSlab.EnumBlockHalf enumblockhalf = (BlockSlab.EnumBlockHalf)iblockstate.getValue(BlockSlab.HALF_PROP);

                if ((side == EnumFacing.UP && enumblockhalf == BlockSlab.EnumBlockHalf.BOTTOM || side == EnumFacing.DOWN && enumblockhalf == BlockSlab.EnumBlockHalf.TOP) && comparable == object)
                {
                    IBlockState iblockstate1 = this.twoOf.getDefaultState().withProperty(iproperty, comparable);

                    if (worldIn.checkNoEntityCollision(this.twoOf.getCollisionBoundingBox(worldIn, pos, iblockstate1)) && worldIn.setBlockState(pos, iblockstate1, 3))
                    {
                        worldIn.playSoundEffect((double)((float)pos.getX() + 0.5F), (double)((float)pos.getY() + 0.5F), (double)((float)pos.getZ() + 0.5F), this.twoOf.stepSound.getPlaceSound(), (this.twoOf.stepSound.getVolume() + 1.0F) / 2.0F, this.twoOf.stepSound.getFrequency() * 0.8F);
                        --stack.stackSize;
                    }

                    return true;
                }
            }

            return this.placeDouble(stack, worldIn, pos.offset(side), object) ? true : super.onItemUse(stack, playerIn, worldIn, pos, side, hitX, hitY, hitZ);
        }
    }

    @SideOnly(Side.CLIENT)
    public boolean canPlaceBlockOnSide(World worldIn, BlockPos pos, EnumFacing facing, EntityPlayer player, ItemStack stack)
    {
        BlockPos blockpos1 = pos;
        IProperty iproperty = this.single.func_176551_l();
        Object object = this.single.func_176553_a(stack);
        IBlockState iblockstate = worldIn.getBlockState(pos);

        if (iblockstate.getBlock() == this.single)
        {
            boolean flag = iblockstate.getValue(BlockSlab.HALF_PROP) == BlockSlab.EnumBlockHalf.TOP;

            if ((facing == EnumFacing.UP && !flag || facing == EnumFacing.DOWN && flag) && object == iblockstate.getValue(iproperty))
            {
                return true;
            }
        }

        pos = pos.offset(facing);
        IBlockState iblockstate1 = worldIn.getBlockState(pos);
        return iblockstate1.getBlock() == this.single && object == iblockstate1.getValue(iproperty) ? true : super.canPlaceBlockOnSide(worldIn, blockpos1, facing, player, stack);
    }

    private boolean placeDouble(ItemStack stack, World worldIn, BlockPos pos, Object obj)
    {
        IBlockState iblockstate = worldIn.getBlockState(pos);

        if (iblockstate.getBlock() == this.single)
        {
            Comparable comparable = iblockstate.getValue(this.single.func_176551_l());

            if (comparable == obj)
            {
                IBlockState iblockstate1 = this.twoOf.getDefaultState().withProperty(this.single.func_176551_l(), comparable);

                if (worldIn.checkNoEntityCollision(this.twoOf.getCollisionBoundingBox(worldIn, pos, iblockstate1)) && worldIn.setBlockState(pos, iblockstate1, 3))
                {
                    worldIn.playSoundEffect((double)((float)pos.getX() + 0.5F), (double)((float)pos.getY() + 0.5F), (double)((float)pos.getZ() + 0.5F), this.twoOf.stepSound.getPlaceSound(), (this.twoOf.stepSound.getVolume() + 1.0F) / 2.0F, this.twoOf.stepSound.getFrequency() * 0.8F);
                    --stack.stackSize;
                }

                return true;
            }
        }

        return false;
    }
}

[nokel81]

May I adapt your code to make slabs in my mod?