Worldgen and random changes

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diff --git a/src/main/java/gregtech/api/objects/XSTR.java b/src/main/java/gregtech/api/objects/XSTR.java
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+package gregtech.api.objects;
+/**
+ * A subclass of java.util.random that implements the Xorshift random number
+ * generator
+ *
+ * - it is 30% faster than the generator from Java's library - it produces
+ * random sequences of higher quality than java.util.Random - this class also
+ * provides a clone() function
+ *
+ * Usage: XSRandom rand = new XSRandom(); //Instantiation x = rand.nextInt();
+ * //pull a random number
+ *
+ * To use the class in legacy code, you may also instantiate an XSRandom object
+ * and assign it to a java.util.Random object: java.util.Random rand = new
+ * XSRandom();
+ *
+ * for an explanation of the algorithm, see
+ * http://demesos.blogspot.com/2011/09/pseudo-random-number-generators.html
+ *
+ * @author Wilfried Elmenreich University of Klagenfurt/Lakeside Labs
+ * http://www.elmenreich.tk
+ *
+ * This code is released under the GNU Lesser General Public License Version 3
+ * http://www.gnu.org/licenses/lgpl-3.0.txt
+ */
+
+import java.util.Random;
+import java.util.concurrent.atomic.AtomicLong;
+
+/**
+ * XSTR - Xorshift ThermiteRandom
+ * Modified by Bogdan-G
+ * 03.06.2016
+ * version 0.0.4
+ */
+public class XSTR extends Random {
+
+    private static final long serialVersionUID = 6208727693524452904L;
+    private long seed;
+    private long last;
+    private static final long GAMMA = 0x9e3779b97f4a7c15L;
+    private static final int PROBE_INCREMENT = 0x9e3779b9;
+    private static final long SEEDER_INCREMENT = 0xbb67ae8584caa73bL;
+    private static final double DOUBLE_UNIT = 0x1.0p-53;  // 1.0  / (1L << 53)
+    private static final float  FLOAT_UNIT  = 0x1.0p-24f; // 1.0f / (1 << 24)
+
+    /*
+     MODIFIED BY: Robotia
+     Modification: Implemented Random class seed generator
+     */
+    /**
+     * Creates a new pseudo random number generator. The seed is initialized to
+     * the current time, as if by
+     * <code>setSeed(System.currentTimeMillis());</code>.
+     */
+    public XSTR() {
+        this(seedUniquifier() ^ System.nanoTime());
+    }
+    private static final AtomicLong seedUniquifier
+            = new AtomicLong(8682522807148012L);
+
+    private static long seedUniquifier() {
+        // L'Ecuyer, "Tables of Linear Congruential Generators of
+        // Different Sizes and Good Lattice Structure", 1999
+        for (;;) {
+            long current = seedUniquifier.get();
+            long next = current * 181783497276652981L;
+            if (seedUniquifier.compareAndSet(current, next)) {
+                return next;
+            }
+        }
+    }
+
+    /**
+     * Creates a new pseudo random number generator, starting with the specified
+     * seed, using <code>setSeed(seed);</code>.
+     *
+     * @param seed the initial seed
+     */
+    public XSTR(long seed) {
+        this.seed = seed;
+    }
+    public boolean nextBoolean() {
+        return next(1) != 0;
+    }
+
+    public double nextDouble() {
+        return (((long)(next(26)) << 27) + next(27)) * DOUBLE_UNIT;
+    }
+    /**
+     * Returns the current state of the seed, can be used to clone the object
+     *
+     * @return the current seed
+     */
+    public synchronized long getSeed() {
+        return seed;
+    }
+
+    /**
+     * Sets the seed for this pseudo random number generator. As described
+     * above, two instances of the same random class, starting with the same
+     * seed, produce the same results, if the same methods are called.
+     *
+     * @param seed the new seed
+     */
+    public synchronized void setSeed(long seed) {
+        this.seed = seed;
+    }
+
+    /**
+     * @return Returns an XSRandom object with the same state as the original
+     */
+    @Override
+    public XSTR clone() {
+        return new XSTR(getSeed());
+    }
+
+    /**
+     * Implementation of George Marsaglia's elegant Xorshift random generator
+     * 30% faster and better quality than the built-in java.util.random see also
+     * see http://www.javamex.com/tutorials/random_numbers/xorshift.shtml
+     *
+     * @param nbits
+     * @return
+     */
+    public int next(int nbits) {
+        long x = seed;
+        x ^= (x << 21);
+        x ^= (x >>> 35);
+        x ^= (x << 4);
+        seed = x;
+        x &= ((1L << nbits) - 1);
+        return (int) x;
+    }
+    boolean haveNextNextGaussian = false;
+    double nextNextGaussian = 0;
+    synchronized public double nextGaussian() {
+        // See Knuth, ACP, Section 3.4.1 Algorithm C.
+        if (haveNextNextGaussian) {
+            haveNextNextGaussian = false;
+            return nextNextGaussian;
+        } else {
+            double v1, v2, s;
+            do {
+                v1 = 2 * nextDouble() - 1; // between -1 and 1
+                v2 = 2 * nextDouble() - 1; // between -1 and 1
+                s = v1 * v1 + v2 * v2;
+            } while (s >= 1 || s == 0);
+            double multiplier = StrictMath.sqrt(-2 * StrictMath.log(s)/s);
+            nextNextGaussian = v2 * multiplier;
+            haveNextNextGaussian = true;
+            return v1 * multiplier;
+        }
+    }
+    /**
+     * Returns a pseudorandom, uniformly distributed {@code int} value between 0
+     * (inclusive) and the specified value (exclusive), drawn from this random
+     * number generator's sequence. The general contract of {@code nextInt} is
+     * that one {@code int} value in the specified range is pseudorandomly
+     * generated and returned. All {@code bound} possible {@code int} values are
+     * produced with (approximately) equal probability. The method
+     * {@code nextInt(int bound)} is implemented by class {@code Random} as if
+     * by:
+     * <pre> {@code
+     * public int nextInt(int bound) {
+     *   if (bound <= 0)
+     *     throw new IllegalArgumentException("bound must be positive");
+     *
+     *   if ((bound & -bound) == bound)  // i.e., bound is a power of 2
+     *     return (int)((bound * (long)next(31)) >> 31);
+     *
+     *   int bits, val;
+     *   do {
+     *       bits = next(31);
+     *       val = bits % bound;
+     *   } while (bits - val + (bound-1) < 0);
+     *   return val;
+     * }}</pre>
+     *
+     * <p>The hedge "approx
+     * imately" is used in the foregoing description only because the next
+     * method is only approximately an unbiased source of independently chosen
+     * bits. If it were a perfect source of randomly chosen bits, then the
+     * algorithm shown would choose {@code int} values from the stated range
+     * with perfect uniformity.
+     * <p>
+     * The algorithm is slightly tricky. It rejects values that would result in
+     * an uneven distribution (due to the fact that 2^31 is not divisible by n).
+     * The probability of a value being rejected depends on n. The worst case is
+     * n=2^30+1, for which the probability of a reject is 1/2, and the expected
+     * number of iterations before the loop terminates is 2.
+     * <p>
+     * The algorithm treats the case where n is a power of two specially: it
+     * returns the correct number of high-order bits from the underlying
+     * pseudo-random number generator. In the absence of special treatment, the
+     * correct number of <i>low-order</i> bits would be returned. Linear
+     * congruential pseudo-random number generators such as the one implemented
+     * by this class are known to have short periods in the sequence of values
+     * of their low-order bits. Thus, this special case greatly increases the
+     * length of the sequence of values returned by successive calls to this
+     * method if n is a small power of two.
+     *
+     * @param bound the upper bound (exclusive). Must be positive.
+     * @return the next pseudorandom, uniformly distributed {@code int} value
+     * between zero (inclusive) and {@code bound} (exclusive) from this random
+     * number generator's sequence
+     * @throws IllegalArgumentException if bound is not positive
+     * @since 1.2
+     */
+    public int nextInt(int bound) {
+        //if (bound <= 0) {
+        //throw new RuntimeException("BadBound");
+        //}
+
+        /*int r = next(31);
+        int m = bound - 1;
+        if ((bound & m) == 0) // i.e., bound is a power of 2
+        {
+            r = (int) ((bound * (long) r) >> 31);
+        } else {
+            for (int u = r;
+                    u - (r = u % bound) + m < 0;
+                    u = next(31))
+                ;
+        }
+        return r;*/
+        //speedup, new nextInt ~+40%
+        last = seed ^ (seed << 21);
+        last ^= (last >>> 35);
+        last ^= (last << 4);
+        seed = last;
+        int out = (int) last % bound;
+        return (out < 0) ? -out : out;
+    }
+    public int nextInt() {
+        return next(32);
+    }
+
+    public float nextFloat() {
+        return next(24) * FLOAT_UNIT;
+    }
+
+    public long nextLong() {
+        // it's okay that the bottom word remains signed.
+        return ((long)(next(32)) << 32) + next(32);
+    }
+
+    public void nextBytes(byte[] bytes_arr) {
+        for (int iba = 0, lenba = bytes_arr.length; iba < lenba; )
+            for (int rndba = nextInt(),
+                 nba = Math.min(lenba - iba, Integer.SIZE/Byte.SIZE);
+                 nba-- > 0; rndba >>= Byte.SIZE)
+                bytes_arr[iba++] = (byte)rndba;
+    }
+}
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