World Gen?

package com.creativemd.randomadditions.common.world;

import com.creativemd.randomadditions.common.systems.ore.SubSystemOre;
import com.creativemd.randomadditions.core.CraftMaterial;
import com.creativemd.randomadditions.core.RandomAdditions;
import cpw.mods.fml.common.IWorldGenerator;
import java.util.ArrayList;
import java.util.Random;
import net.minecraft.block.Block;
import net.minecraft.init.Blocks;
import net.minecraft.world.World;
import net.minecraft.world.WorldProvider;
import net.minecraft.world.chunk.IChunkProvider;
import net.minecraft.world.gen.feature.WorldGenMinable;

public class WorldGenerator
  implements IWorldGenerator
{
  public static boolean generateCopper;
  public static boolean generateTin;
  public static boolean generateRuby;
  public static boolean generateTourmaline;

  public void generate(Random random, int chunkX, int chunkZ, World world, IChunkProvider chunkGenerator, IChunkProvider chunkProvider)
  {
    switch (world.field_73011_w.field_76574_g)
    {
    case -1:
      generateNether(world, random, chunkX * 16, chunkZ * 16);
    case 0:
      generateSurface(world, random, chunkX * 16, chunkZ * 16);
    }
  }

  public void generateSurface(World world, Random random, int blockX, int blockZ)
  {
    for (int i = 0; i < RandomAdditions.materials.size(); i++)
    {
      int meta = SubSystemOre.instance.getMetaByName(((CraftMaterial)RandomAdditions.materials.get(i)).name);
      switch (((CraftMaterial)RandomAdditions.materials.get(i)).generateOre)
      {
      case 1:
        addOreSpawn(meta, SubSystemOre.instance.block, world, random, blockX, blockZ, 0, 7, 1, 0, 16);
        break;
      case 2:
        addOreSpawn(meta, SubSystemOre.instance.block, world, random, blockX, blockZ, 0, 8, 2, 0, 32);
        break;
      case 3:
        addOreSpawn(meta, SubSystemOre.instance.block, world, random, blockX, blockZ, 0, 8, 20, 0, 64);
      }
    }
  }

  public void addOreSpawn(int meta, Block block, World world, Random random, int blockXPos, int blockZPos, int minVeinSize, int maxVeinSize, int chancesToSpawn, int minY, int maxY)
  {
    WorldGenMinable minable = new WorldGenMinable(block, meta, minVeinSize + random.nextInt(maxVeinSize - minVeinSize), Blocks.field_150348_b);
    for (int i = 0; i < chancesToSpawn; i++)
    {
      int posX = blockXPos + random.nextInt(16);
      int posY = minY + random.nextInt(maxY - minY);
      int posZ = blockZPos + random.nextInt(16);
      minable.func_76484_a(world, random, posX, posY, posZ);
    }
  }

  public void generateNether(World world, Random random, int blockX, int blockY) {}

  public String getName()
  {
    return "Random Additions";
  }
}