GenLayer.java

package net.minecraft.world.gen.layer;

import net.minecraft.world.WorldType;

import net.minecraftforge.common.*;
import net.minecraftforge.event.terraingen.*;

public abstract class GenLayer
{
    /** seed from World#getWorldSeed that is used in the LCG prng */
    private long worldGenSeed;

    /** parent GenLayer that was provided via the constructor */
    protected GenLayer parent;

    /**
     * final part of the LCG prng that uses the chunk X, Z coords along with the other two seeds to generate
     * pseudorandom numbers
     */
    private long chunkSeed;

    /** base seed to the LCG prng provided via the constructor */
    private long baseSeed;

    /**
     * the first array item is a linked list of the bioms, the second is the zoom function, the third is the same as the
     * first.
     */
    public static GenLayer[] initializeAllBiomeGenerators(long par0, WorldType par2WorldType)
    {
        GenLayerIsland genlayerisland = new GenLayerIsland(1L);
        GenLayerFuzzyZoom genlayerfuzzyzoom = new GenLayerFuzzyZoom(2000L, genlayerisland);
        GenLayerAddIsland genlayeraddisland = new GenLayerAddIsland(1L, genlayerfuzzyzoom);
        GenLayerZoom genlayerzoom = new GenLayerZoom(2001L, genlayeraddisland);
        genlayeraddisland = new GenLayerAddIsland(2L, genlayerzoom);
        GenLayerAddSnow genlayeraddsnow = new GenLayerAddSnow(2L, genlayeraddisland);
        genlayerzoom = new GenLayerZoom(2002L, genlayeraddsnow);
        genlayeraddisland = new GenLayerAddIsland(3L, genlayerzoom);
        genlayerzoom = new GenLayerZoom(2003L, genlayeraddisland);
        genlayeraddisland = new GenLayerAddIsland(4L, genlayerzoom);
        GenLayerAddMushroomIsland genlayeraddmushroomisland = new GenLayerAddMushroomIsland(5L, genlayeraddisland);
        byte b0 = 4;

        if (par2WorldType == WorldType.LARGE_BIOMES)
        {
            b0 = 6;
        }
        b0 = getModdedBiomeSize(par2WorldType, b0);

        GenLayer genlayer = GenLayerZoom.magnify(1000L, genlayeraddmushroomisland, 0);
        GenLayerRiverInit genlayerriverinit = new GenLayerRiverInit(100L, genlayer);
        genlayer = GenLayerZoom.magnify(1000L, genlayerriverinit, b0 + 2);
        GenLayerRiver genlayerriver = new GenLayerRiver(1L, genlayer);
        GenLayerSmooth genlayersmooth = new GenLayerSmooth(1000L, genlayerriver);
        GenLayer genlayer1 = GenLayerZoom.magnify(1000L, genlayeraddmushroomisland, 0);
        GenLayerBiome genlayerbiome = new GenLayerBiome(200L, genlayer1, par2WorldType);
        genlayer1 = GenLayerZoom.magnify(1000L, genlayerbiome, 2);
        Object object = new GenLayerHills(1000L, genlayer1);

        for (int j = 0; j < b0; ++j)
        {
            object = new GenLayerZoom((long)(1000 + j), (GenLayer)object);

            if (j == 0)
            {
                object = new GenLayerAddIsland(3L, (GenLayer)object);
            }

            if (j == 1)
            {
                object = new GenLayerShore(1000L, (GenLayer)object);
            }

            if (j == 1)
            {
                object = new GenLayerSwampRivers(1000L, (GenLayer)object);
            }
        }

        GenLayerSmooth genlayersmooth1 = new GenLayerSmooth(1000L, (GenLayer)object);
        GenLayerRiverMix genlayerrivermix = new GenLayerRiverMix(100L, genlayersmooth1, genlayersmooth);
        GenLayerVoronoiZoom genlayervoronoizoom = new GenLayerVoronoiZoom(10L, genlayerrivermix);
        genlayerrivermix.initWorldGenSeed(par0);
        genlayervoronoizoom.initWorldGenSeed(par0);
        return new GenLayer[] {genlayerrivermix, genlayervoronoizoom, genlayerrivermix};
    }

    public GenLayer(long par1)
    {
        this.baseSeed = par1;
        this.baseSeed *= this.baseSeed * 6364136223846793005L + 1442695040888963407L;
        this.baseSeed += par1;
        this.baseSeed *= this.baseSeed * 6364136223846793005L + 1442695040888963407L;
        this.baseSeed += par1;
        this.baseSeed *= this.baseSeed * 6364136223846793005L + 1442695040888963407L;
        this.baseSeed += par1;
    }

    /**
     * Initialize layer's local worldGenSeed based on its own baseSeed and the world's global seed (passed in as an
     * argument).
     */
    public void initWorldGenSeed(long par1)
    {
        this.worldGenSeed = par1;

        if (this.parent != null)
        {
            this.parent.initWorldGenSeed(par1);
        }

        this.worldGenSeed *= this.worldGenSeed * 6364136223846793005L + 1442695040888963407L;
        this.worldGenSeed += this.baseSeed;
        this.worldGenSeed *= this.worldGenSeed * 6364136223846793005L + 1442695040888963407L;
        this.worldGenSeed += this.baseSeed;
        this.worldGenSeed *= this.worldGenSeed * 6364136223846793005L + 1442695040888963407L;
        this.worldGenSeed += this.baseSeed;
    }

    /**
     * Initialize layer's current chunkSeed based on the local worldGenSeed and the (x,z) chunk coordinates.
     */
    public void initChunkSeed(long par1, long par3)
    {
        this.chunkSeed = this.worldGenSeed;
        this.chunkSeed *= this.chunkSeed * 6364136223846793005L + 1442695040888963407L;
        this.chunkSeed += par1;
        this.chunkSeed *= this.chunkSeed * 6364136223846793005L + 1442695040888963407L;
        this.chunkSeed += par3;
        this.chunkSeed *= this.chunkSeed * 6364136223846793005L + 1442695040888963407L;
        this.chunkSeed += par1;
        this.chunkSeed *= this.chunkSeed * 6364136223846793005L + 1442695040888963407L;
        this.chunkSeed += par3;
    }

    /**
     * returns a LCG pseudo random number from [0, x). Args: int x
     */
    protected int nextInt(int par1)
    {
        int j = (int)((this.chunkSeed >> 24) % (long)par1);

        if (j < 0)
        {
            j += par1;
        }

        this.chunkSeed *= this.chunkSeed * 6364136223846793005L + 1442695040888963407L;
        this.chunkSeed += this.worldGenSeed;
        return j;
    }

    /**
     * Returns a list of integer values generated by this layer. These may be interpreted as temperatures, rainfall
     * amounts, or biomeList[] indices based on the particular GenLayer subclass.
     */
    public abstract int[] getInts(int i, int j, int k, int l);

    public static byte getModdedBiomeSize(WorldType worldType, byte original)
    {
        WorldTypeEvent.BiomeSize event = new WorldTypeEvent.BiomeSize(worldType, original);
        MinecraftForge.TERRAIN_GEN_BUS.post(event);
        return event.newSize;
    }
}