Merge remote-tracking branch 'effin/new-weather' into new-weather-rework

src/weather_gen.cpp

@@ -5,8 +5,7 @@
 #include <sstream>
 #include <fstream>
 
-const double pi = std::acos(-1);
-const double tau = pi * 2.0;
+const double tau = 2 * std::acos(-1);
 
 weather_generator::weather_generator(unsigned seed) : SEED(seed), Temperature(SEED), Humidity(SEED + 101), Pressure(SEED + 211) { }
 
@@ -20,36 +19,48 @@ w_point weather_generator::get_weather(double x, double y, calendar t) {
     double H2(Humidity.noise(x, y, z) / 4);
     double P(Pressure.noise(x, y, z / 3) * 70);
 
-    // temperature variation
     const double now((double)t.turn_of_year() / (double)calendar::year_turns()); // [0,1)
     const double ctn(cos(tau * now));
-    const double mod_t = 0; // TODO: make this depend on latitude and altitude?
-    const double current_t = this->base_t + mod_t; // Current baseline temperature. Degrees Celsius.
-    const double seasonal_variation = ctn * -1; // Start and end at -1 going up to 1 in summer.
-    const double season_atenuation = ctn / 2 + 1; // Harsh winter nights, hot summers.
-    const double season_dispersion = pow(2, ctn * -1 + 1) - 2.3; // Make summers peak faster and winters not perma-frozen.
-    const double daily_variation = cos( tau * dayFraction ) * season_atenuation + season_dispersion; // Day-night temperature variation.
-
+    // Temperature variation
+    const double mod_t(0); // TODO: make this depend on latitude and altitude?
+    const double current_t(this->base_t + mod_t); // Current baseline temperature. Degrees Celsius.
+    const double seasonal_variation(ctn * -1); // Start and end at -1 going up to 1 in summer.
+    const double season_atenuation(ctn / 2 + 1); // Harsh winter nights, hot summers.
+    const double season_dispersion(pow(2, ctn * -1 + 1) - 2.3); // Make summers peak faster and winters not perma-frozen.
+    double daily_variation(cos( tau * dayFraction ) * season_atenuation + season_dispersion); // Day-night temperature variation.
     T += current_t; // Add baseline to the noise.
-
-    const double D(seasonal_variation * 12 * exp(-pow(current_t * 2.7 / 20 - 0.5, 2)));
-    T += D; // Add season curve offset to account for the winter-summer difference in day-night difference.
-
+    T += seasonal_variation * 12 * exp(-pow(current_t * 2.7 / 20 - 0.5, 2)); // Add season curve offset to account for the winter-summer difference in day-night difference.
     T += daily_variation * 10 * exp(-pow(current_t / 30, 2)); //((4000 / (current_t + 115) - 24) + seasonal_variation); // Add daily variation scaled to the inverse of the current baseline. A very specific and finicky adjustment curve.
-
-    // humidity variation
-    const double mod_h = 0;
-    const double current_h = this->base_h + mod_h;
+    // Humidity variation
+    double mod_h(0);
+    double current_h(this->base_h + mod_h);
     H = std::max(std::min((ctn / 10.0 + (-pow(H, 2)*3 + H2)) * current_h/2.0 + current_h, 100.0), 0.0); // Humidity stays mostly at the mean level, but has low peaks rarely. It's a percentage.
 
-    // pressure variation
-    const double mod_p = 0;
-    const double current_p = this->base_p + mod_p;
     P += seasonal_variation * 20 + current_p; // Pressure is mostly random, but a bit higher on summer and lower on winter. In millibars.
 
     return w_point(T, H, P);
 }
 
+weather_type weather_generator::get_weather_conditions(double x, double y, calendar t) {
+    w_point w(get_weather(x, y , t));
+    weather_type r(WEATHER_CLEAR);
+    if (w.pressure > 1030 && w.humidity < 70) r = WEATHER_SUNNY;
+    if (w.pressure < 1030 && w.humidity > 40) r = WEATHER_CLOUDY;
+    if (r == WEATHER_CLOUDY && (w.humidity > 60 || w.pressure < 1010)) r = WEATHER_DRIZZLE;
+    if (r == WEATHER_DRIZZLE && (w.humidity > 70 || w.pressure < 1000)) r = WEATHER_RAINY;
+    if (r == WEATHER_RAINY && w.pressure < 950) r = WEATHER_THUNDER;
+    if (r == WEATHER_THUNDER && w.pressure < 900) r = WEATHER_LIGHTNING;
+    // TODO: Acid rain needs a different layer or method of determining acidity.
+    if (r == WEATHER_DRIZZLE && w.temperature > 30) r = WEATHER_ACID_DRIZZLE;
+    if (r > WEATHER_DRIZZLE && w.temperature > 30) r = WEATHER_ACID_RAIN;
+    if (w.temperature <= 0) {
+        if (r == WEATHER_DRIZZLE) {r = WEATHER_FLURRIES;}
+        else if (r > WEATHER_DRIZZLE) {r = WEATHER_SNOW;}
+        else if (r > WEATHER_THUNDER) {r = WEATHER_SNOWSTORM;}
+    }
+    return r;
+}
+
 void weather_generator::test_weather() {
     // Outputs a Cata year's worth of weather data to a csv file.
     // Usage:
@@ -59,8 +70,8 @@ void weather_generator::test_weather() {
     std::ostringstream ss;
     testfile.open("weather.output", std::ofstream::trunc);
     testfile << "turn,temperature(C),humidity(%),pressure(mB)\n";
+
     for (calendar i(0); i.get_turn() < 14400 * calendar::year_length(); i+=200) {
-//    for (calendar i(0); i.get_turn() < 1000; i.increment()) {
         ss.str("");
         w_point w = get_weather(0.5,0.5,i);
         ss << i.get_turn() << "," << w.temperature << "," << w.humidity << "," << w.pressure;

src/weather_gen.h

@@ -1,6 +1,7 @@
 #ifndef _WEATHER_GEN_H_
 #define _WEATHER_GEN_H_
 
+#include "weather.h"
 #include "calendar.h"
 #include "PerlinNoise.hpp"
 
@@ -20,7 +21,6 @@ class PerlinNoise;
 
 class weather_generator
 {
-//friend class calendar;
     unsigned SEED;
     // Data source: Wolfram Alpha
     const double base_t = 6.5; // Average temperature of New England
@@ -32,6 +32,7 @@ class weather_generator
 public:
     weather_generator(unsigned seed);
     w_point get_weather(double x, double y, calendar t);
+    weather_type get_weather_conditions(double x, double y, calendar t);
     void test_weather();
 };
 #endif