Add relative humidity to environment data

Author: pmai

osi_environment.proto

@@ -16,7 +16,7 @@ message EnvironmentalConditions
 
     // The time of day.
     //
-    optional TimeOfDay time_of_day = 2;  
+    optional TimeOfDay time_of_day = 2;
 
     // Atmospheric pressure in Pascal at z=0.0 in world frame (about 101325
     // [Pa]).
@@ -29,18 +29,27 @@ message EnvironmentalConditions
     // Unit: [K]
     optional double temperature = 4;
 
+    // Relative humidity in at z=0.0 in world frame.
+    //
+    // Note that physically more relevant measures, like absolute or specific
+    // humidity can be easily derived from relative_humidity, given that the
+    // temperature and atmospheric_pressure are known.
+    //
+    // Unit: [%]
+    optional double relative_humidity = 5;
+
     // Description of the precipitation.
     //
-    optional Precipitation precipitation = 5;
+    optional Precipitation precipitation = 6;
 
     // Description of the fog.
     //
-    optional Fog fog = 6;
-    
+    optional Fog fog = 7;
+
     // Definition of discretized precipitation states according to [1].
     // (I = Intensity of precipitation in mm per hour [mm/h])
     //
-    // \par References: 
+    // \par References:
     // [1] PAULAT, Marcus, et al. A gridded dataset of hourly precipitation in Germany: Its construction, climatology and application. Meteorologische Zeitschrift, 2008, 17. Jg. Nr. 6, S. 719-732.
     enum Precipitation
     {
@@ -82,19 +91,19 @@ message EnvironmentalConditions
     }
 
     // Definition of discretized fog states according to [2].
-    // The bandwidth of thick and dense fog was adjusted to fit the German StVO 
+    // The bandwidth of thick and dense fog was adjusted to fit the German StVO
     // regarding rear fog lights [3].
-    // (V = Visibility in meters [m]) 
+    // (V = Visibility in meters [m])
     //
-    // Visibility is defined as the length of the atmosphere over which a beam 
-    // of light travels before its luminous flux is reduced to 5% of its 
-    // original value (definition used by the Meteorological Office [4]). 
-    // This is approximately equivalent to visibility measured in terms of the 
+    // Visibility is defined as the length of the atmosphere over which a beam
+    // of light travels before its luminous flux is reduced to 5% of its
+    // original value (definition used by the Meteorological Office [4]).
+    // This is approximately equivalent to visibility measured in terms of the
     // contrast of a distant object against its background.
     //
-    // \par References: 
+    // \par References:
     // [2] SHEPARD, Frank D. Reduced visibility due to fog on the highway. Transportation Research Board, 1996.
-    // [3] [StVO §17 chapter 3](https://www.stvo.de/strassenverkehrsordnung/101-17-beleuchtung) 
+    // [3] [StVO §17 chapter 3](https://www.stvo.de/strassenverkehrsordnung/101-17-beleuchtung)
     // [4] [Homepage of the Meteorological Office](http://www.metoffice.gov.uk/guide/weather/observations-guide/how-we-measure-visibility)
     enum Fog
     {
@@ -143,18 +152,18 @@ message EnvironmentalConditions
     // Ambient light is any light in the vehicle's environment that is not
     // emitted by the vehicle itself. It can include sun/moon light, light from
     // other cars, street  lights, etc.
-    // 
+    //
     // Lux [lx] is the SI unit of luminance or illumination of an area of exact
-    // one square metre, which is equal to one lumen per square meter 1 [lx] = 
+    // one square metre, which is equal to one lumen per square meter 1 [lx] =
     // 1 [lm/m^2] [5].
     // The lumen [lm] is the SI derived unit of luminous flux and a measure of
-    // the total quantity of visible light emitted by a source. The lumen is 
-    // defined in relation to the candela [cd] as 1 [lm] =1 [cd sr] where [sr] 
-    // denotes steradian, the unit of solid angle used in 3D geometry analogous 
-    // to the radian. 
+    // the total quantity of visible light emitted by a source. The lumen is
+    // defined in relation to the candela [cd] as 1 [lm] =1 [cd sr] where [sr]
+    // denotes steradian, the unit of solid angle used in 3D geometry analogous
+    // to the radian.
     //
-    // Categorization is done based on natural day/night time illuminance levels 
-    // [6] and standards for required lighting levels on roads [6, 7, 8, 9]. 
+    // Categorization is done based on natural day/night time illuminance levels
+    // [6] and standards for required lighting levels on roads [6, 7, 8, 9].
     //
     // \par References:
     // [5] [The NIST Reference on Constants, Units, and Uncertainty](https://physics.nist.gov/cuu/Units/units.html)
@@ -183,23 +192,23 @@ message EnvironmentalConditions
         AMBIENT_ILLUMINATION_LEVEL2 = 3;
 
         // Level 3 illumination in [1, 3[ [lx]
-        // E.g. Deep to average twilight / Minimum lighting on local low 
+        // E.g. Deep to average twilight / Minimum lighting on local low
         // pedestrian conflict roads.
         AMBIENT_ILLUMINATION_LEVEL3 = 4;
 
         // Level 4 illumination in [3, 10[ [lx]
         // E.g. Average to full twilight / Minimum lighting on collector roads /
-        // Minimum lighting on major and expressway roads with low to average 
+        // Minimum lighting on major and expressway roads with low to average
         // pedestrian conflict.
         AMBIENT_ILLUMINATION_LEVEL4 = 5;
 
         // Level 5 illumination in [10, 20[ [lx]
-        // E.g. Minimum lighting on major and expressway roads with high 
+        // E.g. Minimum lighting on major and expressway roads with high
         // pedestrian conflict.
         AMBIENT_ILLUMINATION_LEVEL5 = 6;
 
         // Level 6 illumination in [20, 400[ [lx]
-        // E.g. Roads with more lighting / Very dark overcast day to sunrise or 
+        // E.g. Roads with more lighting / Very dark overcast day to sunrise or
         // sunset on a clear day.
         AMBIENT_ILLUMINATION_LEVEL6 = 7;
 
@@ -225,10 +234,10 @@ message EnvironmentalConditions
     message TimeOfDay
     {
         // The number of seconds [s] that have passed since midnight local time.
-        // Used for determining the current state of the circadian rhythm of a 
+        // Used for determining the current state of the circadian rhythm of a
         // driver.
         //
-        // \note No changes of daylight saving time or time zones are 
+        // \note No changes of daylight saving time or time zones are
         // considered.
         optional uint32 seconds_since_midnight = 1;
     }