Bukkit

package com.gmail.labuff.shane.UltimateSkyGrid;


import java.util.Arrays;
import java.util.List;
import java.util.Random;
import org.bukkit.Location;
import org.bukkit.Material;
import org.bukkit.World;
import org.bukkit.generator.BlockPopulator;
import org.bukkit.generator.ChunkGenerator;


public class UltimateSkyGridGenerator extends ChunkGenerator {
	
	public int worldHeight;
	
	public boolean canSpawn(World world, int x, int z){
		
		return true;
	}
	
	
	static void setBlock(byte[][] result, int x, int y, int z, byte blkid){
		
		if (result[(y >> 4)] == null) {
			
			result[(y >> 4)] = new byte[4096];
		}
		
		result[(y >> 4)][((y & 0xF) << 8 | z << 4 | x)] = blkid;
	}
	
	public byte[][] generateBlockSections(World world, Random random, int chunkX, int chunkZ, ChunkGenerator.BiomeGrid biomes)
	{
		
		
		if(world.getEnvironment() == World.Environment.NETHER){
			
			worldHeight = UltimateSkyGrid.cNetherHeight;
		}
		else if(world.getEnvironment() == World.Environment.NORMAL){
			
			worldHeight = UltimateSkyGrid.cHeight;
		}
		else{
			
			worldHeight = UltimateSkyGrid.cEndHeight;
		}
		
		byte[][] result = new byte[worldHeight / 16][];
		if (UltimateSkyGrid.genGlass){
			for (int x = 0; x < 16; x++) {
				for (int y = 0; y < worldHeight; y++) {
					for (int z = 0; z < 16; z++) {
						if (x % 4 == 0 && y % 4 == 0 && z % 4 == 0){
							
							int ID = getRandBlockID(world, random, UltimateSkyGrid.allBlocksOneWorld);
							setBlock(result, x, y, z, (byte)ID);
						}						
						else{
							if (y < (UltimateSkyGrid.cHeight - 3)){
								
								int ID = Material.GLASS.getId();
								setBlock(result, x, y, z, (byte)ID);
							}
						}
					}	
				}
			}
		}
		else{
			
			for (int x = 0; x < 16; x += 4) {
				for (int y = 0; y < UltimateSkyGrid.cHeight; y += 4) {
					for (int z = 0; z < 16; z += 4) {
						
						int ID = getRandBlockID(world, random, UltimateSkyGrid.allBlocksOneWorld);
						setBlock(result, x, y, z, (byte)ID);
					}
				}
			}
		}
		return result;
	}
	
	@Override
	public Location getFixedSpawnLocation(World world, Random random){
		
	    return new Location(world, 0.5D,(double) worldHeight, 0.5D);
	}

	
	public List<BlockPopulator> getDefaultPopulators(World world){

		return Arrays.asList(new BlockPopulator[] { new UltimateSkyGridPopulator() });
	}
	
	public int getRandBlockID(World world, Random random, boolean allBlocks){
		
		int randID;
		int r;
		if(world.getEnvironment() == World.Environment.NORMAL){
			if(allBlocks){
				
				r = random.nextInt(10000);
				
				if (r < UltimateSkyGrid.cMythic){
					randID = UltimateSkyGrid.iMythic[random.nextInt(UltimateSkyGrid.iMythic.length)];
					return randID;
				}
				else if (r < UltimateSkyGrid.cUnique){
					randID = UltimateSkyGrid.iUnique[random.nextInt(UltimateSkyGrid.iUnique.length)];
					return randID;
				}
				else if (r < UltimateSkyGrid.cRare){
					randID = UltimateSkyGrid.iRare[random.nextInt(UltimateSkyGrid.iRare.length)];
					return randID;
				}
				else if (r < UltimateSkyGrid.cUncommon){
					randID = UltimateSkyGrid.iUncommon[random.nextInt(UltimateSkyGrid.iUncommon.length)];
					return randID;
				}
				else {
					randID = UltimateSkyGrid.iAbundant[random.nextInt(UltimateSkyGrid.iAbundant.length)];
					return randID;
				}
			}
			else{
				
				r = random.nextInt(10000);
				
				if (r < UltimateSkyGrid.cMythic){
					randID = UltimateSkyGrid.iNormMythic[random.nextInt(UltimateSkyGrid.iNormMythic.length)];
					return randID;
				}
				else if (r < UltimateSkyGrid.cUnique){
					randID = UltimateSkyGrid.iNormUnique[random.nextInt(UltimateSkyGrid.iNormUnique.length)];
					return randID;
				}
				else if (r < UltimateSkyGrid.cRare){
					randID = UltimateSkyGrid.iNormRare[random.nextInt(UltimateSkyGrid.iNormRare.length)];
					return randID;
				}
				else if (r < UltimateSkyGrid.cUncommon){
					randID = UltimateSkyGrid.iNormUncommon[random.nextInt(UltimateSkyGrid.iNormUncommon.length)];
					return randID;
				}
				else {
					randID = UltimateSkyGrid.iNormAbundant[random.nextInt(UltimateSkyGrid.iNormAbundant.length)];
					return randID;
				}
			}
		}
		else if(world.getEnvironment() == World.Environment.NETHER){
			
			r = random.nextInt(100);

			if (r < UltimateSkyGrid.cNethRare){
				randID = UltimateSkyGrid.iNethBlkRare[random.nextInt(UltimateSkyGrid.iNethBlkRare.length)];
				return randID;
			}
			else {
				randID = UltimateSkyGrid.iNethBlkNorm[random.nextInt(UltimateSkyGrid.iNethBlkNorm.length)];
				return randID;
			}
		}
		else{
			
			r = random.nextInt(100);

			if (r < UltimateSkyGrid.cEndRare){
				randID = UltimateSkyGrid.iEndBlkRare[random.nextInt(UltimateSkyGrid.iEndBlkRare.length)];
				return randID;
			}
			else {
				randID = UltimateSkyGrid.iEndBlkNorm[random.nextInt(UltimateSkyGrid.iEndBlkNorm.length)];
				return randID;
			}
		}
	}
}