[Lua API] Added 'daylight_cycle' in sky definition to control its presence and speed.

docs/lua-api-sky.md

@@ -14,6 +14,10 @@ mod:sky {
 		day = {50, 153, 204},
 	},
 
+	daylight_cycle = {
+		speed = 1.0
+	},
+
 	objects = {
 		sun = {
 			texture = "texture-sun",
@@ -50,9 +54,26 @@ color = {
 }
 ```
 
-Possible values:
+Attributes:
 
-- `day`: Sky color at midday
+- `day`: sky color at midday
+
+### `daylight_cycle`
+
+Day/night cycle parameters.
+
+Example:
+```lua
+daylight_cycle = {
+	speed = 1.0
+}
+```
+
+The example above is the minimal code required to add a day/night cycle to a sky.
+
+Attributes:
+
+- `speed`: speed of the cycle (default: `1.0`)
 
 ### `fog_color`
 
@@ -65,9 +86,9 @@ fog_color = {
 }
 ```
 
-Possible values:
+Attributes:
 
-- `day`: Fog color at midday
+- `day`: gog color at midday
 
 ### `id`
 
@@ -84,7 +105,9 @@ IDs are usually of the form `mod:sky` but the `mod:` prefix is prepended automat
 
 #### `moon`
 
-Moon attributes table. Example:
+Moon attributes table.
+
+Example:
 ```lua
 moon = {
 	texture = "texture-moon_phases"
@@ -106,7 +129,9 @@ Attributes:
 
 #### `sun`
 
-Sun attribute table. Example:
+Sun attribute table.
+
+Example:
 ```lua
 sun = {
 	texture = "texture-sun",
@@ -121,7 +146,9 @@ Attributes:
 
 #### `stars`
 
-Stars attribute table. Example:
+Stars attribute table.
+
+Example:
 ```lua
 stars = {
 	count = 1000,

mods/default/sky.lua

@@ -36,6 +36,10 @@ mod:sky {
 		day = {50, 153, 204},
 	},
 
+	daylight_cycle = {
+		speed = 1.0
+	},
+
 	objects = {
 		sun = {
 			texture = "texture-sun", -- FIXME: Use a path instead like block attribute 'tiles'

source/client/graphics/Skybox.cpp

@@ -41,6 +41,7 @@ void Skybox::loadSky(const Sky &sky) {
 	m_sun = CelestialObject{};
 	m_sun.setSize(sun.size, sun.size);
 	m_sun.setPosition(500, -m_sun.width() / 2, -m_sun.height() / 2);
+	m_sun.setRotationSpeed(sky.daylightCycleSpeed());
 
 	try {
 		m_sun.setTexture(sun.texture);
@@ -56,6 +57,7 @@ void Skybox::loadSky(const Sky &sky) {
 	m_moon.setPosition(-500, -m_moon.width() / 2, -m_moon.height() / 2);
 	m_moon.setPhaseCount(moon.phaseCount, moon.phaseSize);
 	m_moon.setCurrentPhase(0);
+	m_moon.setRotationSpeed(sky.daylightCycleSpeed());
 
 	try {
 		m_moon.setTexture(moon.texture);
@@ -75,13 +77,15 @@ void Skybox::loadSky(const Sky &sky) {
 		star.setPosition(650 * ((rand() % 2) * 2 - 1), (rand() % 500) * 2 - 500, (rand() % 500) * 2 - 500);
 		star.setRotationOffset(rand() % GameTime::dayLength);
 		star.setRotationAxis({rand() % 100 / 100.f, rand() % 100 / 100.f, rand() % 100 / 100.f});
+		star.setRotationSpeed(sky.daylightCycleSpeed());
 	}
 }
 
 void Skybox::draw(gk::RenderTarget &target, gk::RenderStates states) const {
 	if (!m_world.sky()) return;
 
-	gk::Color skyColor = GameTime::getSkyColorFromTime(*m_world.sky(), GameTime::getCurrentTime());
+	float time = GameTime::getCurrentTime(0, m_world.sky()->daylightCycleSpeed());
+	gk::Color skyColor = GameTime::getSkyColorFromTime(*m_world.sky(), time);
 	gk::Color starColor = m_world.sky()->color();
 
 	gk::Shader::bind(&m_shader);

source/client/states/GameState.cpp

@@ -210,14 +210,23 @@ void GameState::onGuiScaleChanged(const GuiScaleChangedEvent &event) {
 void GameState::draw(gk::RenderTarget &target, gk::RenderStates states) const {
 	gk::Shader::bind(&m_shader);
 
-	float time = GameTime::getCurrentTime();
 	if (m_world.sky()) {
+		if (m_world.sky()->daylightCycleSpeed()) {
+			float time = GameTime::getCurrentTime(0, m_world.sky()->daylightCycleSpeed());
 			const gk::Color &color = GameTime::getSkyColorFromTime(*m_world.sky(), time);
 			glClearColor(color.r, color.g, color.b, color.a);
 
 			m_shader.setUniform("u_skyColor", color);
 			m_shader.setUniform("u_sunlightIntensity", GameTime::getSunlightIntensityFromTime(time));
 		}
+		else {
+			const gk::Color &color = m_world.sky()->color();
+			glClearColor(color.r, color.g, color.b, color.a);
+
+			m_shader.setUniform("u_skyColor", m_world.sky()->color());
+			m_shader.setUniform("u_sunlightIntensity", 1.f);
+		}
+	}
 
 	gk::Shader::bind(nullptr);
 

source/common/world/Sky.cpp

@@ -37,7 +37,8 @@ void Sky::serialize(sf::Packet &packet) const {
 		<< m_sunDefinition.texture << m_sunDefinition.size
 		<< m_moonDefinition.texture << m_moonDefinition.size
 		<< m_moonDefinition.phaseCount << m_moonDefinition.phaseSize
-		<< m_starsDefinition.count << m_starsDefinition.size;
+		<< m_starsDefinition.count << m_starsDefinition.size
+		<< m_daylightCycleSpeed;
 }
 
 void Sky::deserialize(sf::Packet &packet) {
@@ -45,6 +46,7 @@ void Sky::deserialize(sf::Packet &packet) {
 		>> m_sunDefinition.texture >> m_sunDefinition.size
 		>> m_moonDefinition.texture >> m_moonDefinition.size
 		>> m_moonDefinition.phaseCount >> m_moonDefinition.phaseSize
-		>> m_starsDefinition.count >> m_starsDefinition.size;
+		>> m_starsDefinition.count >> m_starsDefinition.size
+		>> m_daylightCycleSpeed;
 }
 

source/common/world/Sky.hpp

@@ -74,6 +74,9 @@ class Sky : public gk::ISerializable {
 		void setMoonDefinition(const MoonDefinition &moonDefinition) { m_moonDefinition = moonDefinition; }
 		void setStarsDefinition(const StarsDefinition &starsDefinition) { m_starsDefinition = starsDefinition; }
 
+		float daylightCycleSpeed() const { return m_daylightCycleSpeed; }
+		void setDaylightCycleSpeed(float daylightCycleSpeed) { m_daylightCycleSpeed = daylightCycleSpeed; }
+
 	private:
 		u16 m_id;
 		std::string m_stringID;
@@ -84,6 +87,8 @@ class Sky : public gk::ISerializable {
 		SunDefinition m_sunDefinition;
 		MoonDefinition m_moonDefinition;
 		StarsDefinition m_starsDefinition;
+
+		float m_daylightCycleSpeed = 0.f;
 };
 
 #endif // SKY_HPP_

source/server/lua/loader/LuaSkyLoader.cpp

@@ -51,6 +51,11 @@ void LuaSkyLoader::loadSky(const sol::table &table) const {
 		sky.setFogColor(gk::Color{r, g, b, a});
 	}
 
+	if (sol::object obj = table["daylight_cycle"] ; obj.valid()) {
+		sol::table daylightCycleTable = obj.as<sol::table>();
+		sky.setDaylightCycleSpeed(daylightCycleTable["speed"].get_or(0.f));
+	}
+
 	loadObjects(sky, table);
 }