add apart of comment in Chunk.java

src/minecraft/App.java

@@ -0,0 +1,16 @@
+import net.minecraft.util.math.MathHelper;
+
+/**
+ * @author WangTingZheng
+ * @date 2020/7/20 20:43
+ * @features
+ */
+public class App {
+
+    public static void main(String[] args) {
+        byte[] te = new byte[255];
+        for (int i = 0; i < 255; i++) {
+            System.out.println("i="+i+" i >> 4 = "+(i>>4)+"| i & 15 = "+(i&15));
+        }
+    }
+}