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package net.minecraft.src;

public class mod_Block extends BaseMod
{
public static final Block nameHere= new BlockName(160, 0).setBlockName("anyNameHere").setHardness(3F).setResistance(4F).setLightValue(1F);

	public void load()
	{
		nameHere.blockIndexInTexture = ModLoader.addOverride("/terrain.png", "/image.png");
		ModLoader.registerBlock(nameHere);
		ModLoader.addName(nameHere, "In-Game Name Here");
		ModLoader.addRecipe(new ItemStack(nameHere, 1), new Object [] {"#", Character.valueOf('#'), Block.dirt});
	}

	public String getVersion()
	 {
			 return "1.4.7";
	}
}

package net.minecraft.src;

public class BlockNameHere extends Block
{
	public BlockNameHere(int i, int j)
	{
		super(i, j, Material.wood);
	}
	
	public boolean isOpaqueCube()
	{
		return false;
	}
}

package net.minecraft.src;
public class mod_Stairs extends BaseMod
{
	 public static final Block nameHere= new BlockNameHereStairs(170, Block.leaves, 0).setBlockName("stairsNameHere").setHardness(3F).setResistance(4F);
			
	 public void load()
	 {
			 nameHere.blockIndexInTexture = ModLoader.addOverride("/terrain.png", "/imageblock.png");
			 ModLoader.registerBlock(nameHere);
			 ModLoader.addName(nameHere, "In-Game Name Here");
			 ModLoader.addRecipe(new ItemStack(nameHere, 1), new Object [] {"# ", "## ", "###", Character.valueOf('#'), Block.dirt});
	 }
	 public String getVersion()
	 {
			 return "1.4.7";
	 }
}

package net.minecraft.src;

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

public class BlockNameHereStairs extends Block
{
private static final int[][] field_72159_a = new int[][] {{2, 6}, {3, 7}, {2, 3}, {6, 7}, {0, 4}, {1, 5}, {0, 1}, {4, 5}};
private static final int[] field_82545_b = new int[] {1, -1, 0, 0};
private static final int[] field_82546_c = new int[] {0, 0, 1, -1};

/** The block that is used as model for the stair. */
private final Block modelBlock;
private final int field_72158_c;
private boolean field_72156_cr = false;
private int field_72160_cs = 0;

protected BlockNameHereStairs(int par1, Block par2Block, int par3)
{
super(par1, par2Block.blockIndexInTexture, par2Block.blockMaterial);
this.modelBlock = par2Block;
this.field_72158_c = par3;
this.setHardness(par2Block.blockHardness);
this.setResistance(par2Block.blockResistance / 3.0F);
this.setStepSound(par2Block.stepSound);
this.setCreativeTab(CreativeTabs.tabBlock);
}

/**
* Updates the blocks bounds based on its current state. Args: world, x, y, z
*/
public void setBlockBoundsBasedOnState(IBlockAccess par1IBlockAccess, int par2, int par3, int par4)
{
if (this.field_72156_cr)
{
this.setBlockBounds(0.5F * (float)(this.field_72160_cs % 2), 0.5F * (float)(this.field_72160_cs / 2 % 2), 0.5F * (float)(this.field_72160_cs / 4 % 2), 0.5F + 0.5F * (float)(this.field_72160_cs % 2), 0.5F + 0.5F * (float)(this.field_72160_cs / 2 % 2), 0.5F + 0.5F * (float)(this.field_72160_cs / 4 % 2));
}
else
{
this.setBlockBounds(0.0F, 0.0F, 0.0F, 1.0F, 1.0F, 1.0F);
}
}

/**
* Is this block (a) opaque and (B) a full 1m cube? This determines whether or not to render the shared face of two
* adjacent blocks and also whether the player can attach torches, redstone wire, etc to this block.
*/
public boolean isOpaqueCube()
{
return false;
}

/**
* If this block doesn't render as an ordinary block it will return False (examples: signs, buttons, stairs, etc)
*/
public boolean renderAsNormalBlock()
{
return false;
}

/**
* The type of render function that is called for this block
*/
public int getRenderType()
{
return 10;
}

public void func_82541_d(IBlockAccess par1IBlockAccess, int par2, int par3, int par4)
{
int var5 = par1IBlockAccess.getBlockMetadata(par2, par3, par4);

if ((var5 & 4) != 0)
{
this.setBlockBounds(0.0F, 0.5F, 0.0F, 1.0F, 1.0F, 1.0F);
}
else
{
this.setBlockBounds(0.0F, 0.0F, 0.0F, 1.0F, 0.5F, 1.0F);
}
}

public static boolean func_82543_e(int par0)
{
return par0 > 0 && Block.blocksList[par0] instanceof BlockNameHereStairs;
}

private boolean func_82540_f(IBlockAccess par1IBlockAccess, int par2, int par3, int par4, int par5)
{
int var6 = par1IBlockAccess.getBlockId(par2, par3, par4);
return func_82543_e(var6) && par1IBlockAccess.getBlockMetadata(par2, par3, par4) == par5;
}

public boolean func_82542_g(IBlockAccess par1IBlockAccess, int par2, int par3, int par4)
{
int var5 = par1IBlockAccess.getBlockMetadata(par2, par3, par4);
int var6 = var5 & 3;
float var7 = 0.5F;
float var8 = 1.0F;

if ((var5 & 4) != 0)
{
var7 = 0.0F;
var8 = 0.5F;
}

float var9 = 0.0F;
float var10 = 1.0F;
float var11 = 0.0F;
float var12 = 0.5F;
boolean var13 = true;
int var14;
int var15;
int var16;

if (var6 == 0)
{
var9 = 0.5F;
var12 = 1.0F;
var14 = par1IBlockAccess.getBlockId(par2 + 1, par3, par4);
var15 = par1IBlockAccess.getBlockMetadata(par2 + 1, par3, par4);

if (func_82543_e(var14) && (var5 & 4) == (var15 & 4))
{
var16 = var15 & 3;

if (var16 == 3 && !this.func_82540_f(par1IBlockAccess, par2, par3, par4 + 1, var5))
{
var12 = 0.5F;
var13 = false;
}
else if (var16 == 2 && !this.func_82540_f(par1IBlockAccess, par2, par3, par4 - 1, var5))
{
var11 = 0.5F;
var13 = false;
}
}
}
else if (var6 == 1)
{
var10 = 0.5F;
var12 = 1.0F;
var14 = par1IBlockAccess.getBlockId(par2 - 1, par3, par4);
var15 = par1IBlockAccess.getBlockMetadata(par2 - 1, par3, par4);

if (func_82543_e(var14) && (var5 & 4) == (var15 & 4))
{
var16 = var15 & 3;

if (var16 == 3 && !this.func_82540_f(par1IBlockAccess, par2, par3, par4 + 1, var5))
{
var12 = 0.5F;
var13 = false;
}
else if (var16 == 2 && !this.func_82540_f(par1IBlockAccess, par2, par3, par4 - 1, var5))
{
var11 = 0.5F;
var13 = false;
}
}
}
else if (var6 == 2)
{
var11 = 0.5F;
var12 = 1.0F;
var14 = par1IBlockAccess.getBlockId(par2, par3, par4 + 1);
var15 = par1IBlockAccess.getBlockMetadata(par2, par3, par4 + 1);

if (func_82543_e(var14) && (var5 & 4) == (var15 & 4))
{
var16 = var15 & 3;

if (var16 == 1 && !this.func_82540_f(par1IBlockAccess, par2 + 1, par3, par4, var5))
{
var10 = 0.5F;
var13 = false;
}
else if (var16 == 0 && !this.func_82540_f(par1IBlockAccess, par2 - 1, par3, par4, var5))
{
var9 = 0.5F;
var13 = false;
}
}
}
else if (var6 == 3)
{
var14 = par1IBlockAccess.getBlockId(par2, par3, par4 - 1);
var15 = par1IBlockAccess.getBlockMetadata(par2, par3, par4 - 1);

if (func_82543_e(var14) && (var5 & 4) == (var15 & 4))
{
var16 = var15 & 3;

if (var16 == 1 && !this.func_82540_f(par1IBlockAccess, par2 + 1, par3, par4, var5))
{
var10 = 0.5F;
var13 = false;
}
else if (var16 == 0 && !this.func_82540_f(par1IBlockAccess, par2 - 1, par3, par4, var5))
{
var9 = 0.5F;
var13 = false;
}
}
}

this.setBlockBounds(var9, var7, var11, var10, var8, var12);
return var13;
}

public boolean func_82544_h(IBlockAccess par1IBlockAccess, int par2, int par3, int par4)
{
int var5 = par1IBlockAccess.getBlockMetadata(par2, par3, par4);
int var6 = var5 & 3;
float var7 = 0.5F;
float var8 = 1.0F;

if ((var5 & 4) != 0)
{
var7 = 0.0F;
var8 = 0.5F;
}

float var9 = 0.0F;
float var10 = 0.5F;
float var11 = 0.5F;
float var12 = 1.0F;
boolean var13 = false;
int var14;
int var15;
int var16;

if (var6 == 0)
{
var14 = par1IBlockAccess.getBlockId(par2 - 1, par3, par4);
var15 = par1IBlockAccess.getBlockMetadata(par2 - 1, par3, par4);

if (func_82543_e(var14) && (var5 & 4) == (var15 & 4))
{
var16 = var15 & 3;

if (var16 == 3 && !this.func_82540_f(par1IBlockAccess, par2, par3, par4 - 1, var5))
{
var11 = 0.0F;
var12 = 0.5F;
var13 = true;
}
else if (var16 == 2 && !this.func_82540_f(par1IBlockAccess, par2, par3, par4 + 1, var5))
{
var11 = 0.5F;
var12 = 1.0F;
var13 = true;
}
}
}
else if (var6 == 1)
{
var14 = par1IBlockAccess.getBlockId(par2 + 1, par3, par4);
var15 = par1IBlockAccess.getBlockMetadata(par2 + 1, par3, par4);

if (func_82543_e(var14) && (var5 & 4) == (var15 & 4))
{
var9 = 0.5F;
var10 = 1.0F;
var16 = var15 & 3;

if (var16 == 3 && !this.func_82540_f(par1IBlockAccess, par2, par3, par4 - 1, var5))
{
var11 = 0.0F;
var12 = 0.5F;
var13 = true;
}
else if (var16 == 2 && !this.func_82540_f(par1IBlockAccess, par2, par3, par4 + 1, var5))
{
var11 = 0.5F;
var12 = 1.0F;
var13 = true;
}
}
}
else if (var6 == 2)
{
var14 = par1IBlockAccess.getBlockId(par2, par3, par4 - 1);
var15 = par1IBlockAccess.getBlockMetadata(par2, par3, par4 - 1);

if (func_82543_e(var14) && (var5 & 4) == (var15 & 4))
{
var11 = 0.0F;
var12 = 0.5F;
var16 = var15 & 3;

if (var16 == 1 && !this.func_82540_f(par1IBlockAccess, par2 - 1, par3, par4, var5))
{
var13 = true;
}
else if (var16 == 0 && !this.func_82540_f(par1IBlockAccess, par2 + 1, par3, par4, var5))
{
var9 = 0.5F;
var10 = 1.0F;
var13 = true;
}
}
}
else if (var6 == 3)
{
var14 = par1IBlockAccess.getBlockId(par2, par3, par4 + 1);
var15 = par1IBlockAccess.getBlockMetadata(par2, par3, par4 + 1);

if (func_82543_e(var14) && (var5 & 4) == (var15 & 4))
{
var16 = var15 & 3;

if (var16 == 1 && !this.func_82540_f(par1IBlockAccess, par2 - 1, par3, par4, var5))
{
var13 = true;
}
else if (var16 == 0 && !this.func_82540_f(par1IBlockAccess, par2 + 1, par3, par4, var5))
{
var9 = 0.5F;
var10 = 1.0F;
var13 = true;
}
}
}

if (var13)
{
this.setBlockBounds(var9, var7, var11, var10, var8, var12);
}

return var13;
}

/**
* if the specified block is in the given AABB, add its collision bounding box to the given list
*/
public void addCollidingBlockToList(World par1World, int par2, int par3, int par4, AxisAlignedBB par5AxisAlignedBB, List par6List, Entity par7Entity)
{
this.func_82541_d(par1World, par2, par3, par4);
super.addCollidingBlockToList(par1World, par2, par3, par4, par5AxisAlignedBB, par6List, par7Entity);
boolean var8 = this.func_82542_g(par1World, par2, par3, par4);
super.addCollidingBlockToList(par1World, par2, par3, par4, par5AxisAlignedBB, par6List, par7Entity);

if (var8 && this.func_82544_h(par1World, par2, par3, par4))
{
super.addCollidingBlockToList(par1World, par2, par3, par4, par5AxisAlignedBB, par6List, par7Entity);
}

this.setBlockBounds(0.0F, 0.0F, 0.0F, 1.0F, 1.0F, 1.0F);
}

/**
* A randomly called display update to be able to add particles or other items for display
*/
public void randomDisplayTick(World par1World, int par2, int par3, int par4, Random par5Random)
{
this.modelBlock.randomDisplayTick(par1World, par2, par3, par4, par5Random);
}

/**
* Called when the block is clicked by a player. Args: x, y, z, entityPlayer
*/
public void onBlockClicked(World par1World, int par2, int par3, int par4, EntityPlayer par5EntityPlayer)
{
this.modelBlock.onBlockClicked(par1World, par2, par3, par4, par5EntityPlayer);
}

/**
* Called right before the block is destroyed by a player. Args: world, x, y, z, metaData
*/
public void onBlockDestroyedByPlayer(World par1World, int par2, int par3, int par4, int par5)
{
this.modelBlock.onBlockDestroyedByPlayer(par1World, par2, par3, par4, par5);
}

/**
* Goes straight to getLightBrightnessForSkyBlocks for Blocks, does some fancy computing for Fluids
*/
public int getMixedBrightnessForBlock(IBlockAccess par1IBlockAccess, int par2, int par3, int par4)
{
return this.modelBlock.getMixedBrightnessForBlock(par1IBlockAccess, par2, par3, par4);
}

/**
* How bright to render this block based on the light its receiving. Args: iBlockAccess, x, y, z
*/
public float getBlockBrightness(IBlockAccess par1IBlockAccess, int par2, int par3, int par4)
{
return this.modelBlock.getBlockBrightness(par1IBlockAccess, par2, par3, par4);
}

/**
* Returns how much this block can resist explosions from the passed in entity.
*/
public float getExplosionResistance(Entity par1Entity)
{
return this.modelBlock.getExplosionResistance(par1Entity);
}

/**
* Returns which pass should this block be rendered on. 0 for solids and 1 for alpha
*/
public int getRenderBlockPass()
{
return this.modelBlock.getRenderBlockPass();
}

/**
* From the specified side and block metadata retrieves the blocks texture. Args: side, metadata
*/
public int getBlockTextureFromSideAndMetadata(int par1, int par2)
{
return this.modelBlock.getBlockTextureFromSideAndMetadata(par1, this.field_72158_c);
}

/**
* Returns the block texture based on the side being looked at. Args: side
*/
public int getBlockTextureFromSide(int par1)
{
return this.modelBlock.getBlockTextureFromSideAndMetadata(par1, this.field_72158_c);
}

/**
* How many world ticks before ticking
*/
public int tickRate()
{
return this.modelBlock.tickRate();
}

/**
* Returns the bounding box of the wired rectangular prism to render.
*/
public AxisAlignedBB getSelectedBoundingBoxFromPool(World par1World, int par2, int par3, int par4)
{
return this.modelBlock.getSelectedBoundingBoxFromPool(par1World, par2, par3, par4);
}

/**
* Can add to the passed in vector for a movement vector to be applied to the entity. Args: x, y, z, entity, vec3d
*/
public void velocityToAddToEntity(World par1World, int par2, int par3, int par4, Entity par5Entity, Vec3 par6Vec3)
{
this.modelBlock.velocityToAddToEntity(par1World, par2, par3, par4, par5Entity, par6Vec3);
}

/**
* Returns if this block is collidable (only used by Fire). Args: x, y, z
*/
public boolean isCollidable()
{
return this.modelBlock.isCollidable();
}

/**
* Returns whether this block is collideable based on the arguments passed in Args: blockMetaData, unknownFlag
*/
public boolean canCollideCheck(int par1, boolean par2)
{
return this.modelBlock.canCollideCheck(par1, par2);
}

/**
* Checks to see if its valid to put this block at the specified coordinates. Args: world, x, y, z
*/
public boolean canPlaceBlockAt(World par1World, int par2, int par3, int par4)
{
return this.modelBlock.canPlaceBlockAt(par1World, par2, par3, par4);
}

/**
* Called whenever the block is added into the world. Args: world, x, y, z
*/
public void onBlockAdded(World par1World, int par2, int par3, int par4)
{
this.onNeighborBlockChange(par1World, par2, par3, par4, 0);
this.modelBlock.onBlockAdded(par1World, par2, par3, par4);
}

/**
* ejects contained items into the world, and notifies neighbours of an update, as appropriate
*/
public void breakBlock(World par1World, int par2, int par3, int par4, int par5, int par6)
{
this.modelBlock.breakBlock(par1World, par2, par3, par4, par5, par6);
}

/**
* Called whenever an entity is walking on top of this block. Args: world, x, y, z, entity
*/
public void onEntityWalking(World par1World, int par2, int par3, int par4, Entity par5Entity)
{
this.modelBlock.onEntityWalking(par1World, par2, par3, par4, par5Entity);
}

/**
* Ticks the block if it's been scheduled
*/
public void updateTick(World par1World, int par2, int par3, int par4, Random par5Random)
{
this.modelBlock.updateTick(par1World, par2, par3, par4, par5Random);
}

/**
* Called upon block activation (right click on the block.)
*/
public boolean onBlockActivated(World par1World, int par2, int par3, int par4, EntityPlayer par5EntityPlayer, int par6, float par7, float par8, float par9)
{
return this.modelBlock.onBlockActivated(par1World, par2, par3, par4, par5EntityPlayer, 0, 0.0F, 0.0F, 0.0F);
}

/**
* Called upon the block being destroyed by an explosion
*/
public void onBlockDestroyedByExplosion(World par1World, int par2, int par3, int par4)
{
this.modelBlock.onBlockDestroyedByExplosion(par1World, par2, par3, par4);
}

/**
* Called when the block is placed in the world.
*/
public void onBlockPlacedBy(World par1World, int par2, int par3, int par4, EntityLiving par5EntityLiving)
{
int var6 = MathHelper.floor_double((double)(par5EntityLiving.rotationYaw * 4.0F / 360.0F) + 0.5D) & 3;
int var7 = par1World.getBlockMetadata(par2, par3, par4) & 4;

if (var6 == 0)
{
par1World.setBlockMetadataWithNotify(par2, par3, par4, 2 | var7);
}

if (var6 == 1)
{
par1World.setBlockMetadataWithNotify(par2, par3, par4, 1 | var7);
}

if (var6 == 2)
{
par1World.setBlockMetadataWithNotify(par2, par3, par4, 3 | var7);
}

if (var6 == 3)
{
par1World.setBlockMetadataWithNotify(par2, par3, par4, 0 | var7);
}
}

public int func_85104_a(World par1World, int par2, int par3, int par4, int par5, float par6, float par7, float par8, int par9)
{
return par5 != 0 && (par5 == 1 || (double)par7 <= 0.5D) ? par9 : par9 | 4;
}

/**
* Ray traces through the blocks collision from start vector to end vector returning a ray trace hit. Args: world,
* x, y, z, startVec, endVec
*/
public MovingObjectPosition collisionRayTrace(World par1World, int par2, int par3, int par4, Vec3 par5Vec3, Vec3 par6Vec3)
{
MovingObjectPosition[] var7 = new MovingObjectPosition[8];
int var8 = par1World.getBlockMetadata(par2, par3, par4);
int var9 = var8 & 3;
boolean var10 = (var8 & 4) == 4;
int[] var11 = field_72159_a[var9 + (var10 ? 4 : 0)];
this.field_72156_cr = true;
int var14;
int var15;
int var16;

for (int var12 = 0; var12 < 8; ++var12)
{
this.field_72160_cs = var12;
int[] var13 = var11;
var14 = var11.length;

for (var15 = 0; var15 < var14; ++var15)
{
var16 = var13[var15];

if (var16 == var12)
{
;
}
}

var7[var12] = super.collisionRayTrace(par1World, par2, par3, par4, par5Vec3, par6Vec3);
}

int[] var21 = var11;
int var24 = var11.length;

for (var14 = 0; var14 < var24; ++var14)
{
var15 = var21[var14];
var7[var15] = null;
}

MovingObjectPosition var23 = null;
double var22 = 0.0D;
MovingObjectPosition[] var25 = var7;
var16 = var7.length;

for (int var17 = 0; var17 < var16; ++var17)
{
MovingObjectPosition var18 = var25[var17];

if (var18 != null)
{
double var19 = var18.hitVec.squareDistanceTo(par6Vec3);

if (var19 > var22)
{
var23 = var18;
var22 = var19;
}
}
}

return var23;
}
}

• The only change here is that the second argument is a Block and the texture argument is now the third. Set the Block argument to what ever block you want the stairs to get their attributes(texture and material) from. Just leave the texture argument as 0.

• The addCollidingBlockToList method adds the collision box for the block. The 'else if' statements change the collision box depending on the direction that the block is facing.
• All the 'if' statements in the onBlockPlacedBy method just make the block face the player's direction when placed.
• The isOpaqueCube, getRenderType, renderAsNormalBlock and the other methods in the class are well explained in Javadoc comments in the code.

package net.minecraft.src;
public class mod_Slab extends BaseMod
{
public static final Block nameHereSingleSlab = new BlockNameHereSlab(250, false).setBlockName("anyNameHereSlabSingle").setHardness(3F).setResistance(4F);
public static final Block nameHereDoubleSlab = new BlockNameHereSlab(251, true).setBlockName("anyNameHereSlabDouble").setHardness(3F).setResistance(4F);
public void load()
{
nameHereSingleSlab.blockIndexInTexture = ModLoader.addOverride("/terrain.png", "/imageslab2.png");
ModLoader.registerBlock(nameHereSingleSlab);
ModLoader.addName(nameHereSingleSlab, "In-Game Name Here");
ModLoader.addRecipe(new ItemStack(nameHereSingleSlab, 1), new Object [] {"#", Character.valueOf('#'), Block.cobblestone});

nameHereDoubleSlab.blockIndexInTexture = ModLoader.addOverride("/terrain.png", "/imageslab.png");
ModLoader.registerBlock(nameHereDoubleSlab);
ModLoader.addName(nameHereDoubleSlab, "In-Game Name Here");
ModLoader.addRecipe(new ItemStack(nameHereDoubleSlab, 1), new Object [] {"#", Character.valueOf('#'), Block.cobblestone});
}
public String getVersion()
{
return "1.4.7";
}
}

package net.minecraft.src;
import java.util.List;
import java.util.Random;
public class BlockNameHereSlab extends BlockHalfSlab
{
/** The list of the types of step blocks. */
public BlockNameHereSlab(int par1, boolean par2)
{
super(par1, par2, Material.wood);
this.setCreativeTab(CreativeTabs.tabBlock);
setLightOpacity(0);
}
/**
* Returns the block texture based on the side being looked at. Args: side
*/
public int getBlockTextureFromSide(int par1)
{
return blockIndexInTexture;
}
/**
* Returns the ID of the items to drop on destruction.
*/
public int idDropped(int par1, Random par2Random, int par3)
{
return mod_Slab.nameHereSingleSlab.blockID;
}
public void onBlockPlacedBy(World par1World, int par2, int par3, int par4, EntityLiving par5EntityLiving)
{
if(par1World.getBlockId(par2, par3 - 1, par4) == mod_Slab.nameHereSingleSlab.blockID)
{
par1World.setBlockWithNotify(par2, par3, par4, 0);
par1World.setBlockWithNotify(par2, par3 - 1, par4, mod_Slab.nameHereDoubleSlab.blockID);
}
}
/**
* Returns an item stack containing a single instance of the current block type. 'par1' is the block's subtype/damage
* and is ignored for blocks which do not support subtypes. Blocks which cannot be harvested should return null.
*/
protected ItemStack createStackedBlock(int par1)
{
return new ItemStack(mod_Slab.nameHereSingleSlab.blockID, 2, par1 & 7);
}

public String getFullSlabName(int var1)
{
return null;
}
}

• In this tutorial, we are actually adding two blocks. One is a single slab. One is the double version of that slab.
• There are two parameters we need to have for the slab blocks. The first, as always, is the id of the block. The second is a boolean instead of an int. This boolean is whether or not the block is a double slab. Obviously we make it false here for only a single slab and true here for a double slab.

• The block class extends BlockHalfSlab. This does most of the work for us in setting the block bounds and other similar things.
• We set the light opacity to 0 to stop most lighting bugs.
• Even though the getBlockTextureFromSide method is unused you need to leave it in the code otherwise you will get Stack Traces.
• The idDropped method is exactly the same as is used in normal blocks.
• The onBlockPlacedBy method is something I have added myself. It allows slabs to be stacked like Vanilla slabs. It is a bit of a shortcut but it works pretty much flawlessly.
• The onBlockPlacedBy method has 5 parameters. They are the World; par2, par3 and par4 are all the X, Y, Z coordinates in the world, respectively. The final parameter is EntityLiving. It is the entity that places the block. We don't use it at all in what we're doing.
• The if statement checks if the block below where we are placing is equal to a single slab. If it is true then it sets the block that was just placed to air and sets the single slab below to a double slab block. Take a look at the world generation tutorials for more details.
• The createStackedBlock method is explained in the Javadoc comment in the code.
• The getFullSlabName method is used in the Vanilla slabs to give them the correct name. We aren't using it in this as we don't have any metadata subtypes.