[docs] Add info about Distance sensor settings and usage

Author: rajat2004

docs/sensors.md

@@ -35,7 +35,7 @@ Behind the scenes, `createDefaultSensorSettings` method in [AirSimSettings.hpp](
 
 The default sensor list can be configured in settings json:
 
-```JSON
+```json
 "DefaultSensors": {
     "Barometer": {
          "SensorType": 1,
@@ -72,7 +72,7 @@ If a vehicle provides its sensor list, it **must** provide the whole list. Selec
 A vehicle specific sensor list can be specified in the vehicle settings part of the json.
 e.g.,
 
-```
+```json
     "Vehicles": {
 
         "Drone1": {
@@ -105,6 +105,42 @@ e.g.,
 Each sensor-type has its own set of settings as well.
 Please see [lidar](lidar.md) for example of Lidar specific settings.
 
+#### Distance Sensor
+
+By default, Distance Sensor points to the front of the vehicle. It can be pointed in any direction by modifying the settings
+
+Configurable Parameters -
+
+Parameter        | Description
+-----------------|------------
+X Y Z            | Position of the sensor relative to the vehicle (in NED, in meters) (Default (0,0,0))
+Yaw Pitch Roll   | Orientation of the sensor relative to the vehicle (degrees) (Default (0,0,0))
+MinDistance      | Minimum distance measured by distance sensor (metres, only used to fill Mavlink message for PX4) (Default 0.2m)
+MaxDistance      | Maximum distance measured by distance sensor (metres) (Default 40.0m)
+
+For example, to make the sensor point towards the ground (for altitude measurement similar to barometer), the orientation can be modified as follows -
+
+```json
+"Distance": {
+    "SensorType": 5,
+    "Enabled" : true,
+    "Yaw": 0, "Pitch": -90, "Roll": 0
+}
+```
+
+##### Server side visualization for debugging
+
+Be default, the points hit by distance sensor are not drawn on the viewport. To enable the drawing of hit points on the viewport, please enable setting `DrawDebugPoints` via settings json. E.g. -
+
+```json
+"Distance": {
+    "SensorType": 5,
+    "Enabled" : true,
+    ...
+    "DrawDebugPoints": true
+}
+```
+
 ## Sensor APIs
 Jump straight to [`hello_drone.py`](https://github.com/Microsoft/AirSim/blob/master/PythonClient/multirotor/hello_drone.py) or [`hello_drone.cpp`](https://github.com/Microsoft/AirSim/blob/master/HelloDrone/main.cpp) for example usage, or see follow below for the full API.
 
@@ -117,7 +153,7 @@ Jump straight to [`hello_drone.py`](https://github.com/Microsoft/AirSim/blob/mas
 
     Python
     ```python
-    barometer_data = getBarometerData(barometer_name = "", vehicle_name = "")
+    barometer_data = client.getBarometerData(barometer_name = "", vehicle_name = "")
     ```
 
 - IMU
@@ -129,7 +165,7 @@ Jump straight to [`hello_drone.py`](https://github.com/Microsoft/AirSim/blob/mas
 
     Python
     ```python
-    imu_data = getImuData(imu_name = "", vehicle_name = "")
+    imu_data = client.getImuData(imu_name = "", vehicle_name = "")
     ```
 
 - GPS
@@ -140,7 +176,7 @@ Jump straight to [`hello_drone.py`](https://github.com/Microsoft/AirSim/blob/mas
     ```
     Python
     ```python
-    gps_data = getGpsData(gps_name = "", vehicle_name = "")
+    gps_data = client.getGpsData(gps_name = "", vehicle_name = "")
     ```
 
 - Magnetometer
@@ -151,18 +187,18 @@ Jump straight to [`hello_drone.py`](https://github.com/Microsoft/AirSim/blob/mas
     ```
     Python
     ```python
-    magnetometer_data = getMagnetometerData(magnetometer_name = "", vehicle_name = "")
+    magnetometer_data = client.getMagnetometerData(magnetometer_name = "", vehicle_name = "")
     ```
 
 - Distance sensor
 
     C++
     ```cpp
-    msr::airlib::DistanceBase::Output getDistanceSensorData(const std::string& distance_sensor_name = "", const std::string& vehicle_name = "");
+    msr::airlib::DistanceSensorData getDistanceSensorData(const std::string& distance_sensor_name = "", const std::string& vehicle_name = "");
     ```
     Python
     ```python
-    distance_sensor_name = getDistanceSensorData(distance_sensor_name = "", vehicle_name = "")
+    distance_sensor_data = client.getDistanceSensorData(distance_sensor_name = "", vehicle_name = "")
     ```
 
 - Lidar