Wind & Turbulence updates from Liberation

Tune turbulence values.

Modify the range of values used to choose a wind speed.

Wind speed at high elevation IRL can range from 20 to 160 knots around the globe.
You may see wind speed generated here up to 100+ knots, but generally around 40 or so.
IRL wind speed appears to depend on the latitude of the sun, not in this implementation.

Note increased wind speeds in the changelog.

Limit wind speed to 97 knots.

Made minor adjustments to wind speed calculation.

Calculate turbulance.

Turbulance is based off time of day, and day of year.
Each theatre may adjust their turbulance parameters.

Spell turbulence correctly.

changelog.md

@@ -41,6 +41,8 @@ Saves from 5.x are not compatible with 6.0.
 * **[Mission Generation]** Added performance option to not cull IADS when culling would affect how mission is played at target area.
 * **[Mission Generation]** Reworked the ground object generation which now uses a new layout system
 * **[Mission Generation]** Added information about the modulation (AM/FM) of the assigned frequencies to the kneeboard and assign AM modulation instead of FM for JTAC.
+* **[Mission Generation]** Adjusted wind speeds.  Wind speeds at high altitude are generally higher now.
+* **[Mission Generation]** Added turbulence.  Higher in Summer and Winter, also higher at day time than at night time.
 * **[Factions]** Updated the Faction file structure. Older custom faction files will not work correctly and have to be updated to the new structure.
 * **[Flight Planning]**  Added preset formations for different flight types at hold, join, ingress, and split waypoints.  Air to Air flights will tend toward line-abreast and spread-four formations.  Air to ground flights will tend towards trail formation.
 * **[Flight Planning]** Added the ability to plan tankers for recovery on package flights.  AI does not plan.

game/missiongenerator/environmentgenerator.py

@@ -17,6 +17,7 @@ class EnvironmentGenerator:
     def set_atmospheric(self, atmospheric: AtmosphericConditions) -> None:
         self.mission.weather.qnh = atmospheric.qnh.mm_hg
         self.mission.weather.season_temperature = atmospheric.temperature_celsius
+        self.mission.weather.turbulence_at_ground = int(atmospheric.turbulence_per_10cm)
 
     def set_clouds(self, clouds: Optional[Clouds]) -> None:
         if clouds is None:

game/missiongenerator/kneeboard.py

@@ -400,6 +400,9 @@ class BriefingPage(KneeboardPage):
             f"Temperature: {round(self.weather.atmospheric.temperature_celsius)} °C at sea level"
         )
         writer.text(f"QNH: {qnh_in_hg} inHg / {qnh_mm_hg} mmHg / {qnh_hpa} hPa")
+        writer.text(
+            f"Turbulence: {round(self.weather.atmospheric.turbulence_per_10cm)} per 10cm at ground level."
+        )
 
         fl = self.flight
 

game/theater/seasonalconditions.py

@@ -45,4 +45,9 @@ class SeasonalConditions:
     winter_avg_temperature: float
     temperature_day_night_difference: float
 
+    high_avg_yearly_turbulence_per_10cm: float
+    low_avg_yearly_turbulence_per_10cm: float
+    solar_noon_turbulence_per_10cm: float
+    midnight_turbulence_per_10cm: float
+
     weather_type_chances: dict[Season, WeatherTypeChances]

game/theater/theaterloader.py

@@ -57,6 +57,23 @@ class SeasonData:
         )
 
 
+@dataclass(frozen=True)
+class TurbulenceData:
+    high_avg_yearly_turbulence_per_10cm: float | None
+    low_avg_yearly_turbulence_per_10cm: float | None
+    solar_noon_turbulence_per_10cm: float | None
+    midnight_turbulence_per_10cm: float | None
+
+    @staticmethod
+    def from_yaml(data: dict[str, Any]) -> TurbulenceData:
+        return TurbulenceData(
+            data.get("high_avg_yearly_turbulence_per_10cm"),
+            data.get("low_avg_yearly_turbulence_per_10cm"),
+            data.get("solar_noon_turbulence_per_10cm"),
+            data.get("midnight_turbulence_per_10cm"),
+        )
+
+
 class TheaterLoader:
     THEATER_RESOURCE_DIR = Path("resources/theaters")
 
@@ -113,6 +130,7 @@ class TheaterLoader:
         spring = SeasonData.from_yaml(climate_data["seasons"]["spring"])
         summer = SeasonData.from_yaml(climate_data["seasons"]["summer"])
         fall = SeasonData.from_yaml(climate_data["seasons"]["fall"])
+        turbulence = TurbulenceData.from_yaml(climate_data["turbulence"])
         if summer.average_pressure is None:
             raise RuntimeError(
                 f"{self.descriptor_path} does not define a summer average pressure"
@@ -129,12 +147,32 @@ class TheaterLoader:
             raise RuntimeError(
                 f"{self.descriptor_path} does not define a winter average temperature"
             )
+        if turbulence.high_avg_yearly_turbulence_per_10cm is None:
+            raise RuntimeError(
+                f"{self.descriptor_path} does not define a yearly average high turbulence"
+            )
+        if turbulence.low_avg_yearly_turbulence_per_10cm is None:
+            raise RuntimeError(
+                f"{self.descriptor_path} does not define a yearly average low turbulence"
+            )
+        if turbulence.solar_noon_turbulence_per_10cm is None:
+            raise RuntimeError(
+                f"{self.descriptor_path} does not define a solar noon turbulence"
+            )
+        if turbulence.midnight_turbulence_per_10cm is None:
+            raise RuntimeError(
+                f"{self.descriptor_path} does not define a midnight turbulence"
+            )
         return SeasonalConditions(
             summer.average_pressure,
             winter.average_pressure,
             summer.average_temperature,
             winter.average_temperature,
             climate_data["day_night_temperature_difference"],
+            turbulence.high_avg_yearly_turbulence_per_10cm,
+            turbulence.low_avg_yearly_turbulence_per_10cm,
+            turbulence.solar_noon_turbulence_per_10cm,
+            turbulence.midnight_turbulence_per_10cm,
             {
                 Season.Winter: winter.weather,
                 Season.Spring: spring.weather,

game/weather.py

@@ -2,6 +2,7 @@ from __future__ import annotations
 
 import datetime
 import logging
+import math
 import random
 from dataclasses import dataclass, field
 from typing import Optional, TYPE_CHECKING
@@ -11,7 +12,15 @@ from dcs.weather import CloudPreset, Weather as PydcsWeather, Wind
 
 from game.theater.seasonalconditions import determine_season
 from game.timeofday import TimeOfDay
-from game.utils import Distance, Heading, Pressure, inches_hg, interpolate, meters
+from game.utils import (
+    Distance,
+    Heading,
+    Pressure,
+    inches_hg,
+    interpolate,
+    knots,
+    meters,
+)
 
 if TYPE_CHECKING:
     from game.settings import Settings
@@ -27,6 +36,9 @@ class AtmosphericConditions:
     #: Temperature at sea level in Celcius.
     temperature_celsius: float
 
+    #: Turbulence per 10 cm.
+    turbulence_per_10cm: float
+
 
 @dataclass(frozen=True)
 class WindConditions:
@@ -99,18 +111,38 @@ class Weather:
             day,
         )
 
+        seasonal_turbulence = self.interpolate_seasonal_turbulence(
+            seasonal_conditions.high_avg_yearly_turbulence_per_10cm,
+            seasonal_conditions.low_avg_yearly_turbulence_per_10cm,
+            day,
+        )
+
+        day_turbulence = seasonal_conditions.solar_noon_turbulence_per_10cm
+        night_turbulence = seasonal_conditions.midnight_turbulence_per_10cm
+        time_of_day_turbulence = self.interpolate_solar_activity(
+            time_of_day, day_turbulence, night_turbulence
+        )
+
+        random_turbulence = random.normalvariate(mu=0, sigma=0.5)
+
+        turbulence = abs(
+            seasonal_turbulence + time_of_day_turbulence + random_turbulence
+        )
+
         if time_of_day == TimeOfDay.Day:
             temperature += seasonal_conditions.temperature_day_night_difference / 2
         if time_of_day == TimeOfDay.Night:
             temperature -= seasonal_conditions.temperature_day_night_difference / 2
         pressure += self.pressure_adjustment
         temperature += self.temperature_adjustment
+        turbulence += self.turbulence_adjustment
         logging.debug(
             "Weather: Before random: temp {} press {}".format(temperature, pressure)
         )
         conditions = AtmosphericConditions(
             qnh=self.random_pressure(pressure),
             temperature_celsius=self.random_temperature(temperature),
+            turbulence_per_10cm=turbulence,
         )
         logging.debug(
             "Weather: After random: temp {} press {}".format(
@@ -127,6 +159,10 @@ class Weather:
     def temperature_adjustment(self) -> float:
         raise NotImplementedError
 
+    @property
+    def turbulence_adjustment(self) -> float:
+        raise NotImplementedError
+
     def generate_clouds(self) -> Optional[Clouds]:
         raise NotImplementedError
 
@@ -147,15 +183,52 @@ class Weather:
         wind_direction_2000m = wind_direction + Heading.random(-90, 90)
         wind_direction_8000m = wind_direction + Heading.random(-90, 90)
         at_0m_factor = 1
-        at_2000m_factor = 2
-        at_8000m_factor = 3
+        at_2000m_factor = 3 + random.choice([0, 0, 0, 0, 0, 1, 1])
+
+        high_alt_variation = random.choice(
+            [
+                -3,
+                -3,
+                -2,
+                -2,
+                -2,
+                -2,
+                -2,
+                -2,
+                -1,
+                -1,
+                -1,
+                -1,
+                -1,
+                -1,
+                -1,
+                0,
+                0,
+                0,
+                1,
+                1,
+                2,
+                3,
+            ]
+        )
+        at_8000m_factor = at_2000m_factor + 5 + high_alt_variation
+
         base_wind = random.randint(minimum, maximum)
 
+        # DCS is limited to 97 knots wind speed.
+        max_supported_wind_speed = knots(97).meters_per_second
+
         return WindConditions(
             # Always some wind to make the smoke move a bit.
             at_0m=Wind(wind_direction.degrees, max(1, base_wind * at_0m_factor)),
-            at_2000m=Wind(wind_direction_2000m.degrees, base_wind * at_2000m_factor),
-            at_8000m=Wind(wind_direction_8000m.degrees, base_wind * at_8000m_factor),
+            at_2000m=Wind(
+                wind_direction_2000m.degrees,
+                min(max_supported_wind_speed, base_wind * at_2000m_factor),
+            ),
+            at_8000m=Wind(
+                wind_direction_8000m.degrees,
+                min(max_supported_wind_speed, base_wind * at_8000m_factor),
+            ),
         )
 
     @staticmethod
@@ -198,6 +271,42 @@ class Weather:
         winter_factor = distance_from_peak_summer / day_of_year_peak_summer
         return interpolate(summer_value, winter_value, winter_factor, clamp=True)
 
+    @staticmethod
+    def interpolate_seasonal_turbulence(
+        high_value: float, low_value: float, day: datetime.date
+    ) -> float:
+        day_of_year = day.timetuple().tm_yday
+        day_of_year_peak_summer = 183
+        distance_from_peak_summer = -day_of_year_peak_summer + day_of_year
+
+        amplitude = 0.5 * (high_value - low_value)
+        offset = amplitude + low_value
+
+        # A high peak in summer and winter, between high_value and low_value.
+        return (
+            amplitude * math.cos(4 * math.pi * distance_from_peak_summer / 365.25)
+            + offset
+        )
+
+    @staticmethod
+    def interpolate_solar_activity(
+        time_of_day: TimeOfDay, high: float, low: float
+    ) -> float:
+
+        scale: float = 0
+
+        match time_of_day:
+            case TimeOfDay.Dawn:
+                scale = 0.4
+            case TimeOfDay.Day:
+                scale = 1
+            case TimeOfDay.Dusk:
+                scale = 0.6
+            case TimeOfDay.Night:
+                scale = 0
+
+        return interpolate(value1=low, value2=high, factor=scale, clamp=True)
+
 
 class ClearSkies(Weather):
     @property
@@ -208,6 +317,10 @@ class ClearSkies(Weather):
     def temperature_adjustment(self) -> float:
         return 3.0
 
+    @property
+    def turbulence_adjustment(self) -> float:
+        return 0.0
+
     def generate_clouds(self) -> Optional[Clouds]:
         return None
 
@@ -227,6 +340,10 @@ class Cloudy(Weather):
     def temperature_adjustment(self) -> float:
         return 0.0
 
+    @property
+    def turbulence_adjustment(self) -> float:
+        return 0.75
+
     def generate_clouds(self) -> Optional[Clouds]:
         return Clouds.random_preset(rain=False)
 
@@ -247,6 +364,10 @@ class Raining(Weather):
     def temperature_adjustment(self) -> float:
         return -3.0
 
+    @property
+    def turbulence_adjustment(self) -> float:
+        return 1.5
+
     def generate_clouds(self) -> Optional[Clouds]:
         return Clouds.random_preset(rain=True)
 
@@ -255,7 +376,7 @@ class Raining(Weather):
         return None
 
     def generate_wind(self) -> WindConditions:
-        return self.random_wind(1, 6)
+        return self.random_wind(2, 6)
 
 
 class Thunderstorm(Weather):
@@ -267,6 +388,10 @@ class Thunderstorm(Weather):
     def temperature_adjustment(self) -> float:
         return -3.0
 
+    @property
+    def turbulence_adjustment(self) -> float:
+        return 3.0
+
     def generate_clouds(self) -> Optional[Clouds]:
         return Clouds(
             base=self.random_cloud_base(),

resources/theaters/caucasus/info.yaml

@@ -37,3 +37,8 @@ climate:
         raining: 30
         cloudy: 50
         clear: 20
+  turbulence:
+    high_avg_yearly_turbulence_per_10cm: 9
+    low_avg_yearly_turbulence_per_10cm: 3.5
+    solar_noon_turbulence_per_10cm: 3.5
+    midnight_turbulence_per_10cm: -3

resources/theaters/falklands/info.yaml

@@ -46,3 +46,8 @@ climate:
         raining: 30
         cloudy: 45
         clear: 25
+  turbulence:
+    high_avg_yearly_turbulence_per_10cm: 8
+    low_avg_yearly_turbulence_per_10cm: 4.5
+    solar_noon_turbulence_per_10cm: 3
+    midnight_turbulence_per_10cm: -2

resources/theaters/marianaislands/info.yaml

@@ -38,3 +38,8 @@ climate:
         raining: 45
         cloudy: 30
         clear: 20
+  turbulence:
+    high_avg_yearly_turbulence_per_10cm: 6.5
+    low_avg_yearly_turbulence_per_10cm: 4.5
+    solar_noon_turbulence_per_10cm: 2
+    midnight_turbulence_per_10cm: -1

resources/theaters/nevada/info.yaml

@@ -37,3 +37,8 @@ climate:
         raining: 10
         cloudy: 45
         clear: 45
+  turbulence:
+    high_avg_yearly_turbulence_per_10cm: 17
+    low_avg_yearly_turbulence_per_10cm: 3.5
+    solar_noon_turbulence_per_10cm: 3.5
+    midnight_turbulence_per_10cm: -3

resources/theaters/normandy/info.yaml

@@ -37,3 +37,8 @@ climate:
         raining: 30
         cloudy: 50
         clear: 20
+  turbulence:
+    high_avg_yearly_turbulence_per_10cm: 9
+    low_avg_yearly_turbulence_per_10cm: 3.5
+    solar_noon_turbulence_per_10cm: 3.5
+    midnight_turbulence_per_10cm: -3

resources/theaters/persian gulf/info.yaml

@@ -38,3 +38,8 @@ climate:
         raining: 2
         cloudy: 28
         clear: 70
+  turbulence:
+    high_avg_yearly_turbulence_per_10cm: 9
+    low_avg_yearly_turbulence_per_10cm: 4.5
+    solar_noon_turbulence_per_10cm: 5.5
+    midnight_turbulence_per_10cm: -2

resources/theaters/syria/info.yaml

@@ -37,3 +37,8 @@ climate:
         raining: 15
         cloudy: 35
         clear: 50
+  turbulence:
+    high_avg_yearly_turbulence_per_10cm: 9
+    low_avg_yearly_turbulence_per_10cm: 3.5
+    solar_noon_turbulence_per_10cm: 3.5
+    midnight_turbulence_per_10cm: -3

resources/theaters/the channel/info.yaml

@@ -38,3 +38,8 @@ climate:
         raining: 30
         cloudy: 50
         clear: 20
+  turbulence:
+    high_avg_yearly_turbulence_per_10cm: 9
+    low_avg_yearly_turbulence_per_10cm: 3.5
+    solar_noon_turbulence_per_10cm: 3.5
+    midnight_turbulence_per_10cm: -3