Use std::chrono for worldTimeHEADmain

Defines a world time type alias, a game time scale factor (the rate at
which world time progresses compare to real time) and display the world
time on the status bar.

2 files changed, 13 insertions, 7 deletions

diff --git a/game/environment.cpp b/game/environment.cpp
index f8da316..58a5b53 100644
--- a/game/environment.cpp
+++ b/game/environment.cpp
@@ -5,15 +5,17 @@
 
 constexpr Direction2D DONCASTER = {-1.1_degrees, 53.5_degrees};
 
-Environment::Environment() : worldTime {"2026-06-01T12:00:00"_time_t}, earthPos {DONCASTER} { }
+Environment::Environment() : worldTime {"2026-06-01T12:00:00"_seconds}, gameTimeScaleFactor {1440}, earthPos {DONCASTER}
+{
+}
 
 void
-Environment::tick(TickDuration)
+Environment::tick(TickDuration elapsed)
 {
-	worldTime += 50;
+	worldTime += std::chrono::duration_cast<WorldTime::duration>(elapsed * gameTimeScaleFactor);
 }
 
-time_t
+Environment::WorldTime
 Environment::getWorldTime() const
 {
 	return worldTime;
@@ -22,7 +24,7 @@ Environment::getWorldTime() const
 Direction2D
 Environment::getSunPos() const
 {
-	return getSunPos(earthPos, worldTime);
+	return getSunPos(earthPos, worldTime.time_since_epoch().count());
 }
 
 void
diff --git a/game/environment.h b/game/environment.h
index 271792f..94211bc 100644
--- a/game/environment.h
+++ b/game/environment.h
@@ -2,20 +2,24 @@
 
 #include "config/types.h"
 #include "worldobject.h"
+#include <chrono>
 
 class SceneRenderer;
 class SceneProvider;
 
 class Environment : public WorldObject {
 public:
+	using WorldTime = std::chrono::utc_time<std::chrono::seconds>;
+
 	Environment();
 	void tick(TickDuration elapsed) override;
 	void render(const SceneRenderer &, const SceneProvider &) const;
 	[[nodiscard]] Direction2D getSunPos() const;
-	[[nodiscard]] time_t getWorldTime() const;
+	[[nodiscard]] WorldTime getWorldTime() const;
 	[[nodiscard]] static Direction2D getSunPos(Direction2D position, time_t time);
 
 private:
-	time_t worldTime;
+	WorldTime worldTime;
+	uint16_t gameTimeScaleFactor;
 	glm::vec<2, Angle> earthPos;
 };