WIP: Day/night cycle

resources/shaders/fog.f.glsl

@@ -2,9 +2,22 @@
 
 uniform vec4 u_fogColor;
 
+uniform int u_time;
+
 vec4 fog(vec4 color, float fogCoord, float fogStart, float fogEnd) {
 	float fog = clamp((fogEnd - fogCoord) / (fogEnd - fogStart), 0.0, 1.0);
 
-	return mix(u_fogColor, color, fog);
+	const float pi = 3.1415927;
+	const float frequency = 480000;
+
+	float time = mod(u_time, 960000);
+	float sunlight = clamp((1 + cos(2 * pi / frequency * time) * 4.0), 0.0, 1.0);
+
+	float red = clamp(sunlight - 0.55, 0.0, 0.45);
+	float green = clamp(sunlight - 0.35, 0.0, 0.65);
+	float blue = clamp(sunlight - 0.09, 0.0, 0.91);
+
+	return mix(vec4(red, green, blue, 1.0), color, fog);
+	/* return mix(u_fogColor, color, fog); */
 }
 

resources/shaders/game.f.glsl

@@ -10,8 +10,11 @@ varying float v_blockFace;
 varying float v_dist;
 
 uniform int u_renderDistance;
+
 uniform sampler2D u_tex;
 
+uniform int u_time;
+
 // Get light color
 vec4 light(vec4 color, vec3 lightColor, vec4 lightPosition, float ambientIntensity, float diffuseIntensity);
 
@@ -50,6 +53,12 @@ void main() {
 
 	float minBrightness = 2.0 / 16.0;
 	if (lightCheck != -1.) {
+		const float pi = 3.1415927;
+		const float frequency = 480000;
+
+		float time = mod(u_time, 960000);
+		float sunlight = clamp(v_lightValue.x * 0.5 * (1 + cos(2 * pi / frequency * time) * 4.0), 3, 15);
+
 		float ambientIntensity = max(max(v_lightValue.x, v_lightValue.y) / 16.0, minBrightness);
 		float diffuseIntensity = max(v_lightValue.x, v_lightValue.y) / 32.0;
 
@@ -64,7 +73,9 @@ void main() {
 		if (blockFace == 2. || blockFace == 3.)
 			ambientIntensity = max(ambientIntensity * 0.9, minBrightness);
 
-		color = light(color, vec3(1.0, 1.0, 1.0), v_coord3d, ambientIntensity, diffuseIntensity);
+		float lightval = clamp(sunlight / 16.0, v_lightValue.y / 16.0, 1.0);
+
+		color = light(color, vec3(lightval, lightval, lightval), v_coord3d, ambientIntensity, diffuseIntensity);
 	}
 
 	color.rgb *= v_ambientOcclusion;

source/client/states/GameState.cpp

@@ -24,6 +24,8 @@
  *
  * =====================================================================================
  */
+#include <algorithm>
+#include <cmath>
 #include <iostream>
 
 #include <glm/gtc/matrix_transform.hpp>
@@ -208,9 +210,20 @@ void GameState::onGuiScaleChanged(const GuiScaleChangedEvent &event) {
 
 void GameState::draw(gk::RenderTarget &target, gk::RenderStates states) const {
 	// FIXME: This uniform is not used anymore since water/leaves effects are disabled
-	// gk::Shader::bind(&m_shader);
-	// m_shader.setUniform("u_time", gk::GameClock::getInstance().getTicks());
-	// gk::Shader::bind(nullptr);
+	// Now used by day/night cycle
+	gk::Shader::bind(&m_shader);
+	m_shader.setUniform("u_time", (int)gk::GameClock::getInstance().getTicks());
+	gk::Shader::bind(nullptr);
+
+	float pi = 3.1415927;
+	float frequency = 480000;
+	float time = gk::GameClock::getInstance().getTicks() % 960000;
+	float sunlight = std::min(std::max((1 + std::cos(2 * pi / frequency * time) * 2.0), 0.0), 1.0);
+	float red = std::min(std::max(sunlight - 0.55, 0.0), 0.45);
+	float green = std::min(std::max(sunlight - 0.35, 0.0), 0.65);
+	float blue = std::min(std::max(sunlight - 0.09, 0.0), 0.91);
+
+	glClearColor(red, green, blue, 1.0);
 
 	m_fbo.begin();