implement function to set integer position precision in bits

src/utils/position_util.js

@@ -1,5 +1,27 @@
 class PositionUtil {
 
+    /**
+     * Obfuscates the provided latitude or longitude down to the provided precision in bits.
+     * This is based on the same logic in the official meshtastic firmware.
+     * https://github.com/meshtastic/firmware/blob/0a93261c0646f93aea518cc0599e547e9dc0e997/src/modules/PositionModule.cpp#L187
+     */
+    static setPositionPrecision(latitudeOrLongitudeInteger, precision) {
+
+        // check if we should use the provided precision
+        if(precision > 0 && precision < 32){
+
+            // apply bitmask to reduce precision of position to wanted bits
+            latitudeOrLongitudeInteger = latitudeOrLongitudeInteger & (0xFFFFFFFF << (32 - precision));
+
+            // we want the imprecise position to be the middle of the possible location
+            latitudeOrLongitudeInteger += (1 << (31 - precision));
+
+        }
+
+        return latitudeOrLongitudeInteger;
+
+    }
+
     /**
      * Truncates the provided latitude or longitude to a maximum of x decimal places
      * e.g: 12.3456789 with 2 decimal places would be 12.34