added spawnpoint data

src/main/java/kaptainwutax/seedcracker/cracker/SpawnPointData.java

@@ -0,0 +1,38 @@
+package kaptainwutax.seedcracker.cracker;
+
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.util.math.ChunkPos;
+import net.minecraft.world.biome.Biome;
+
+import java.util.List;
+import java.util.Random;
+
+public class SpawnPointData {
+
+	private BlockPos center;
+	private int distanceSquared;
+
+	public SpawnPointData(BlockPos center, int maxDistance) {
+		this.center = center;
+		this.distanceSquared = maxDistance * maxDistance;
+	}
+
+	public boolean test(FakeBiomeSource source) {
+		BlockPos spawnPos = getSpawnPoint(source);
+
+		int distanceX = spawnPos.getX() - this.center.getX();
+		distanceX *= distanceX;
+		int distanceZ = spawnPos.getZ() - this.center.getZ();
+		distanceZ *= distanceZ;
+		return distanceX + distanceZ <= this.distanceSquared;
+	}
+
+	public static BlockPos getSpawnPoint(FakeBiomeSource source) {
+		List<Biome> spawnBiomes = source.getSpawnBiomes();
+		Random random = new Random(source.getSeed());
+		BlockPos spawnPos = source.locateBiome(0, 63, 0, 256, spawnBiomes, random);
+		ChunkPos chunkPos = spawnPos == null ? new ChunkPos(0, 0) : new ChunkPos(spawnPos);
+		return chunkPos.getCenterBlockPos().add(0, 64, 0);
+	}
+
+}