From 7222deeb561891c6a51ba8f40f44ed39708d8569 Mon Sep 17 00:00:00 2001
From: "C. J. Howard" <cjhoward@protonmail.com>
Date: Wed, 23 Sep 2020 14:11:05 -0700
Subject: [PATCH] Add weather system

---
 CMakeLists.txt                          |   1 +
 src/game/bootloader.cpp                 |  47 ++++++++-
 src/game/game-context.hpp               |   2 +
 src/game/states/play-state.cpp          |   7 +-
 src/game/systems/control-system.cpp     |   2 +
 src/game/systems/control-system.hpp     |  14 +++
 src/game/systems/weather-system.cpp     | 124 ++++++++++++++++++++++++
 src/game/systems/weather-system.hpp     |  64 ++++++++++++
 src/renderer/passes/material-pass.cpp   |  11 ++-
 src/renderer/passes/material-pass.hpp   |   4 +
 src/renderer/passes/shadow-map-pass.cpp |  36 +++----
 src/renderer/passes/shadow-map-pass.hpp |   4 +
 src/renderer/passes/sky-pass.cpp        |  31 +++---
 src/renderer/passes/sky-pass.hpp        |   7 ++
 14 files changed, 314 insertions(+), 40 deletions(-)
 create mode 100644 src/game/systems/weather-system.cpp
 create mode 100644 src/game/systems/weather-system.hpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index b80be9e..1405aa0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -14,6 +14,7 @@ find_package(SDL2 REQUIRED COMPONENTS SDL2::SDL2-static SDL2::SDL2main CONFIG)
 find_package(OpenAL REQUIRED CONFIG)
 find_library(physfs REQUIRED NAMES physfs-static PATHS "${CMAKE_PREFIX_PATH}/lib")
 
+
 # Determine dependencies
 set(STATIC_LIBS
 	dr_wav
diff --git a/src/game/bootloader.cpp b/src/game/bootloader.cpp
index c6091fd..aec9e97 100644
--- a/src/game/bootloader.cpp
+++ b/src/game/bootloader.cpp
@@ -78,6 +78,7 @@
 #include "game/systems/spatial-system.hpp"
 #include "game/systems/tracking-system.hpp"
 #include "game/systems/painting-system.hpp"
+#include "game/systems/weather-system.hpp"
 #include "game/components/marker-component.hpp"
 #include "game/entity-commands.hpp"
 #include "utility/paths.hpp"
@@ -753,6 +754,7 @@ void setup_animation(game_context* ctx)
 	ctx->focal_point_tween->set_interpolator(math::lerp<float3, float>);
 	
 	// Set material pass tweens
+	ctx->overworld_sky_pass->set_time_tween(ctx->time_tween);
 	ctx->overworld_material_pass->set_time_tween(ctx->time_tween);
 	ctx->overworld_material_pass->set_focal_point_tween(ctx->focal_point_tween);
 	ctx->underworld_material_pass->set_time_tween(ctx->time_tween);
@@ -855,6 +857,18 @@ void setup_systems(game_context* ctx)
 	ctx->painting_system = new painting_system(*ctx->ecs_registry, event_dispatcher, ctx->resource_manager);
 	ctx->painting_system->set_scene(ctx->overworld_scene);
 	
+	// Setup weather system
+	ctx->weather_system = new weather_system(*ctx->ecs_registry);
+	ctx->weather_system->set_ambient_light(ctx->sun_indirect);
+	ctx->weather_system->set_sun_light(ctx->sun_direct);
+	ctx->weather_system->set_sky_pass(ctx->overworld_sky_pass);
+	ctx->weather_system->set_shadow_map_pass(ctx->overworld_shadow_map_pass);
+	ctx->weather_system->set_material_pass(ctx->overworld_material_pass);
+	if (ctx->config->has("time_scale"))
+	{
+		ctx->weather_system->set_time_scale(ctx->config->get<float>("time_scale"));
+	}
+	
 	// Setup render system
 	ctx->render_system = new ::render_system(*ctx->ecs_registry);
 	ctx->render_system->add_layer(ctx->overworld_scene);
@@ -1030,6 +1044,8 @@ void setup_controls(game_context* ctx)
 	ctx->input_event_router->add_mapping(game_controller_axis_mapping(ctx->control_system->get_zoom_in_control(), nullptr, game_controller_axis::trigger_right, false));
 	ctx->input_event_router->add_mapping(key_mapping(ctx->control_system->get_rotate_ccw_control(), nullptr, scancode::q));
 	ctx->input_event_router->add_mapping(key_mapping(ctx->control_system->get_rotate_cw_control(), nullptr, scancode::e));
+	ctx->input_event_router->add_mapping(key_mapping(ctx->control_system->get_fast_forward_control(), nullptr, scancode::dot));
+	ctx->input_event_router->add_mapping(key_mapping(ctx->control_system->get_rewind_control(), nullptr, scancode::comma));
 	
 	
 	ctx->input_event_router->add_mapping(key_mapping(ctx->control_system->get_equip_brush_control(), nullptr, scancode::one));
@@ -1143,8 +1159,36 @@ void setup_controls(game_context* ctx)
 		}
 	);
 	
-
 	
+	float time_scale = ctx->config->get<float>("time_scale");
+	ctx->control_system->get_fast_forward_control()->set_activated_callback
+	(
+		[ctx, time_scale]()
+		{
+			ctx->weather_system->set_time_scale(time_scale * 100.0f);
+		}
+	);
+	ctx->control_system->get_fast_forward_control()->set_deactivated_callback
+	(
+		[ctx, time_scale]()
+		{
+			ctx->weather_system->set_time_scale(time_scale);
+		}
+	);
+	ctx->control_system->get_rewind_control()->set_activated_callback
+	(
+		[ctx, time_scale]()
+		{
+			ctx->weather_system->set_time_scale(time_scale * -100.0f);
+		}
+	);
+	ctx->control_system->get_rewind_control()->set_deactivated_callback
+	(
+		[ctx, time_scale]()
+		{
+			ctx->weather_system->set_time_scale(time_scale);
+		}
+	);
 	
 	// Make lens tool's model instance unculled, so its shadow is always visible.
 	model_instance* lens_model_instance = ctx->render_system->get_model_instance(ctx->lens_entity);
@@ -1201,6 +1245,7 @@ void setup_callbacks(game_context* ctx)
 			ctx->constraint_system->update(t, dt);
 			ctx->tracking_system->update(t, dt);
 			ctx->painting_system->update(t, dt);
+			ctx->weather_system->update(t, dt);
 			
 			//(*ctx->focal_point_tween)[1] = ctx->orbit_cam->get_focal_point();
 			
diff --git a/src/game/game-context.hpp b/src/game/game-context.hpp
index fc8ec2d..a91a757 100644
--- a/src/game/game-context.hpp
+++ b/src/game/game-context.hpp
@@ -86,6 +86,7 @@ class cli;
 class outline_pass;
 class tracking_system;
 class painting_system;
+class weather_system;
 struct biome;
 template <typename T> class animation;
 template <typename T> class material_property;
@@ -241,6 +242,7 @@ struct game_context
 	spatial_system* spatial_system;
 	tracking_system* tracking_system;
 	painting_system* painting_system;
+	weather_system* weather_system;
 	
 	// Game
 	biome* biome;
diff --git a/src/game/states/play-state.cpp b/src/game/states/play-state.cpp
index 355d0bf..80ecf40 100644
--- a/src/game/states/play-state.cpp
+++ b/src/game/states/play-state.cpp
@@ -54,6 +54,7 @@
 #include "game/systems/camera-system.hpp"
 #include "game/systems/render-system.hpp"
 #include "game/systems/tool-system.hpp"
+#include "game/systems/weather-system.hpp"
 #include "game/biome.hpp"
 #include "utility/fundamental-types.hpp"
 #include "utility/gamma.hpp"
@@ -93,11 +94,11 @@ void play_state_enter(game_context* ctx)
 	sky_pass->set_zenith_color(ctx->biome->zenith_color);
 	
 	texture_2d* sky_palette = ctx->resource_manager->load<texture_2d>("sky-palette.png");
-	sky_palette->set_wrapping(texture_wrapping::repeat, texture_wrapping::clamp);
-	sky_palette->set_filters(texture_min_filter::linear, texture_mag_filter::linear);
+	sky_palette->set_wrapping(texture_wrapping::clamp, texture_wrapping::clamp);
+	sky_palette->set_filters(texture_min_filter::nearest, texture_mag_filter::nearest);
 	sky_pass->set_sky_palette(sky_palette);
 	
-	ctx->tool_system->set_sun_direction(ctx->sun_direct->get_direction());
+	ctx->weather_system->set_time_of_day(6.0f * 60.0f * 60.0f);
 
 	resource_manager* resource_manager = ctx->resource_manager;
 	entt::registry& ecs_registry = *ctx->ecs_registry;
diff --git a/src/game/systems/control-system.cpp b/src/game/systems/control-system.cpp
index 6802c43..7f8cd6d 100644
--- a/src/game/systems/control-system.cpp
+++ b/src/game/systems/control-system.cpp
@@ -60,6 +60,8 @@ control_system::control_system(entt::registry& registry):
 	control_set.add_control(&next_marker_control);
 	control_set.add_control(&previous_marker_control);
 	control_set.add_control(&use_tool_control);
+	control_set.add_control(&fast_forward_control);
+	control_set.add_control(&rewind_control);
 	
 	// Set deadzone at 15% for all controls
 	const std::list<control*>* controls = control_set.get_controls();
diff --git a/src/game/systems/control-system.hpp b/src/game/systems/control-system.hpp
index 65702f9..51ec5f3 100644
--- a/src/game/systems/control-system.hpp
+++ b/src/game/systems/control-system.hpp
@@ -80,6 +80,8 @@ public:
 	control* get_next_marker_control();
 	control* get_previous_marker_control();
 	control* get_use_tool_control();
+	control* get_fast_forward_control();
+	control* get_rewind_control();
 
 private:
 	virtual void handle_event(const mouse_moved_event& event);
@@ -110,6 +112,8 @@ private:
 	control next_marker_control;
 	control previous_marker_control;
 	control use_tool_control;
+	control fast_forward_control;
+	control rewind_control;
 
 	float zoom_speed;
 	float min_elevation;
@@ -269,5 +273,15 @@ inline control* control_system::get_use_tool_control()
 	return &use_tool_control;
 }
 
+inline control* control_system::get_fast_forward_control()
+{
+	return &fast_forward_control;
+}
+
+inline control* control_system::get_rewind_control()
+{
+	return &rewind_control;
+}
+
 #endif // ANTKEEPER_CONTROL_SYSTEM_HPP
 
diff --git a/src/game/systems/weather-system.cpp b/src/game/systems/weather-system.cpp
new file mode 100644
index 0000000..2b9c1b7
--- /dev/null
+++ b/src/game/systems/weather-system.cpp
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2020  Christopher J. Howard
+ *
+ * This file is part of Antkeeper source code.
+ *
+ * Antkeeper source code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Antkeeper source code is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Antkeeper source code.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "game/systems/weather-system.hpp"
+#include "scene/directional-light.hpp"
+#include "renderer/passes/sky-pass.hpp"
+#include "renderer/passes/shadow-map-pass.hpp"
+#include "renderer/passes/material-pass.hpp"
+#include <cmath>
+
+weather_system::weather_system(entt::registry& registry):
+	entity_system(registry),
+	ambient_light(nullptr),
+	sun_light(nullptr),
+	moon_light(nullptr),
+	shadow_light(nullptr),
+	sky_pass(nullptr),
+	shadow_map_pass(nullptr),
+	material_pass(nullptr),
+	time_of_day(0.0f),
+	time_scale(1.0f),
+	sun_direction{0.0f, -1.0f, 0.0f}
+{}
+
+void weather_system::update(double t, double dt)
+{
+	set_time_of_day(time_of_day + dt * time_scale);
+}
+
+void weather_system::set_ambient_light(::ambient_light* light)
+{
+	this->ambient_light = light;
+}
+
+void weather_system::set_sun_light(directional_light* light)
+{
+	sun_light = light;
+	
+	if (sky_pass)
+	{
+		sky_pass->set_sun_light(sun_light);
+	}
+}
+
+void weather_system::set_moon_light(directional_light* light)
+{
+	moon_light = light;
+}
+
+void weather_system::set_sky_pass(::sky_pass* pass)
+{
+	sky_pass = pass;
+	
+	if (sky_pass)
+	{
+		sky_pass->set_sun_light(sun_light);
+	}
+}
+
+void weather_system::set_shadow_map_pass(::shadow_map_pass* pass)
+{
+	shadow_map_pass = pass;
+	
+	if (shadow_map_pass)
+	{
+		shadow_map_pass->set_light(shadow_light);
+	}
+}
+
+void weather_system::set_material_pass(::material_pass* pass)
+{
+	material_pass = pass;
+	
+	if (material_pass)
+	{
+		material_pass->set_shadow_strength(0.75f);
+	}
+}
+
+void weather_system::set_time_of_day(float t)
+{
+	static constexpr float seconds_per_day = 24.0f * 60.0f * 60.0f;
+	time_of_day = std::fmod(t, seconds_per_day);
+	
+	sun_azimuth = 0.0f;
+	sun_elevation = (time_of_day / seconds_per_day) * math::two_pi<float> - math::half_pi<float>;
+	
+	math::quaternion<float> sun_azimuth_rotation = math::angle_axis(sun_azimuth, float3{0, 1, 0});
+	math::quaternion<float> sun_elevation_rotation = math::angle_axis(sun_elevation, float3{-1, 0, 0});
+	math::quaternion<float> sun_rotation = math::normalize(sun_azimuth_rotation * sun_elevation_rotation);
+	sun_direction = math::normalize(sun_rotation * float3{0, 0, -1});
+	
+	if (sun_light)
+	{
+		sun_light->set_rotation(sun_rotation);
+	}
+	
+	shadow_light = sun_light;
+	if (shadow_map_pass)
+	{
+		shadow_map_pass->set_light(shadow_light);
+	}
+}
+
+void weather_system::set_time_scale(float scale)
+{
+	time_scale = scale;
+}
diff --git a/src/game/systems/weather-system.hpp b/src/game/systems/weather-system.hpp
new file mode 100644
index 0000000..4924eda
--- /dev/null
+++ b/src/game/systems/weather-system.hpp
@@ -0,0 +1,64 @@
+/*
+ * Copyright (C) 2020  Christopher J. Howard
+ *
+ * This file is part of Antkeeper source code.
+ *
+ * Antkeeper source code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * Antkeeper source code is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with Antkeeper source code.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef ANTKEEPER_WEATHER_SYSTEM_HPP
+#define ANTKEEPER_WEATHER_SYSTEM_HPP
+
+#include "entity-system.hpp"
+#include "utility/fundamental-types.hpp"
+
+class sky_pass;
+class shadow_map_pass;
+class material_pass;
+class ambient_light;
+class directional_light;
+
+class weather_system:
+	public entity_system
+{
+public:
+	weather_system(entt::registry& registry);
+	virtual void update(double t, double dt);
+	
+	void set_ambient_light(ambient_light* light);
+	void set_sun_light(directional_light* light);
+	void set_moon_light(directional_light* light);
+	void set_sky_pass(::sky_pass* pass);
+	void set_shadow_map_pass(::shadow_map_pass* pass);
+	void set_material_pass(::material_pass* pass);
+	
+	void set_time_of_day(float t);
+	void set_time_scale(float scale);
+	
+private:
+	float time_of_day;
+	float time_scale;
+	float sun_azimuth;
+	float sun_elevation;
+	float3 sun_direction;
+	ambient_light* ambient_light;
+	directional_light* sun_light;
+	directional_light* moon_light;
+	directional_light* shadow_light;
+	sky_pass* sky_pass;
+	shadow_map_pass* shadow_map_pass;
+	material_pass* material_pass;
+};
+
+#endif // ANTKEEPER_WEATHER_SYSTEM_HPP
diff --git a/src/renderer/passes/material-pass.cpp b/src/renderer/passes/material-pass.cpp
index e8a88fe..d6f393c 100644
--- a/src/renderer/passes/material-pass.cpp
+++ b/src/renderer/passes/material-pass.cpp
@@ -60,7 +60,8 @@ material_pass::material_pass(::rasterizer* rasterizer, const ::framebuffer* fram
 	mouse_position({0.0f, 0.0f}),
 	focal_point_tween(nullptr),
 	shadow_map_pass(nullptr),
-	shadow_map(nullptr)
+	shadow_map(nullptr),
+	shadow_strength(1.0f)
 {
 	soft_shadows_texture = resource_manager->load<texture_2d>("tree-shadow.png");
 	soft_shadows_texture->set_wrapping(texture_wrapping::clamp, texture_wrapping::clamp);
@@ -464,6 +465,8 @@ void material_pass::render(render_context* context) const
 					parameters->shadow_map_split_distances->upload(shadow_map_split_distances);
 				if (parameters->shadow_map && shadow_map)
 					parameters->shadow_map->upload(shadow_map);
+				if (parameters->shadow_strength)
+					parameters->shadow_strength->upload(shadow_strength);
 			}
 			
 			// Upload material properties to shader
@@ -504,6 +507,11 @@ void material_pass::set_time_tween(const tween<double>* time)
 	this->time_tween = time;
 }
 
+void material_pass::set_shadow_strength(float strength)
+{
+	this->shadow_strength = strength;
+}
+
 void material_pass::set_focal_point_tween(const tween<float3>* focal_point)
 {
 	this->focal_point_tween = focal_point;
@@ -545,6 +553,7 @@ const material_pass::parameter_set* material_pass::load_parameter_set(const shad
 	parameters->shadow_map_matrices = program->get_input("shadow_map_matrices");
 	parameters->shadow_map_split_distances = program->get_input("shadow_map_split_distances");
 	parameters->shadow_map = program->get_input("shadow_map");
+	parameters->shadow_strength = program->get_input("shadow_strength");
 
 	// Add parameter set to map of parameter sets
 	parameter_sets[program] = parameters;
diff --git a/src/renderer/passes/material-pass.hpp b/src/renderer/passes/material-pass.hpp
index f4e3077..90a625f 100644
--- a/src/renderer/passes/material-pass.hpp
+++ b/src/renderer/passes/material-pass.hpp
@@ -52,6 +52,8 @@ public:
 	/// Sets the time tween, which is interpolated between updates
 	void set_time_tween(const tween<double>* time);
 	
+	void set_shadow_strength(float strength);
+	
 	void set_focal_point_tween(const tween<float3>* focal_point);	
 	
 	const ::shadow_map_pass* shadow_map_pass;
@@ -98,6 +100,7 @@ private:
 		const shader_input* shadow_map_matrices;
 		const shader_input* shadow_map_split_distances;
 		const shader_input* shadow_map;
+		const shader_input* shadow_strength;
 	};
 
 	const parameter_set* load_parameter_set(const shader_program* program) const;
@@ -108,6 +111,7 @@ private:
 	float2 mouse_position;
 	const tween<float3>* focal_point_tween;
 	texture_2d* soft_shadows_texture;
+	float shadow_strength;
 	
 	int max_ambient_light_count;
 	int max_point_light_count;
diff --git a/src/renderer/passes/shadow-map-pass.cpp b/src/renderer/passes/shadow-map-pass.cpp
index 16ef536..82a02ea 100644
--- a/src/renderer/passes/shadow-map-pass.cpp
+++ b/src/renderer/passes/shadow-map-pass.cpp
@@ -60,7 +60,8 @@ void shadow_map_pass::distribute_frustum_splits(float* split_distances, std::siz
 
 shadow_map_pass::shadow_map_pass(::rasterizer* rasterizer, const ::framebuffer* framebuffer, resource_manager* resource_manager):
 	render_pass(rasterizer, framebuffer),
-	split_scheme_weight(0.5f)
+	split_scheme_weight(0.5f),
+	light(nullptr)
 {
 	// Load skinned shader program
 	unskinned_shader_program = resource_manager->load<::shader_program>("depth-unskinned.glsl");
@@ -87,6 +88,12 @@ shadow_map_pass::~shadow_map_pass()
 
 void shadow_map_pass::render(render_context* context) const
 {
+	// Abort if no directional light was set
+	if (!light)
+	{
+		return;
+	}
+	
 	rasterizer->use_framebuffer(*framebuffer);
 	
 	// Disable blending
@@ -103,28 +110,6 @@ void shadow_map_pass::render(render_context* context) const
 	// Get camera
 	const ::camera& camera = *context->camera;
 	
-	// Find the first active directional light
-	const std::list<scene_object_base*>* lights = context->scene->get_objects(light::object_type_id);
-	const ::directional_light* light = nullptr;
-	for (const scene_object_base* object: *lights)
-	{
-		// Skip inactive lights
-		if (!object->is_active())
-			continue;
-		
-		if (static_cast<const ::light*>(object)->get_light_type() == light_type::directional)
-		{
-			light = static_cast<const ::directional_light*>(object);
-			break;
-		}
-	}
-	
-	// Abort if no directional light was found
-	if (!light)
-	{
-		return;
-	}
-	
 	// Calculate distances to the depth clipping planes of each frustum split
 	float clip_near = camera.get_clip_near_tween().interpolate(context->alpha);
 	float clip_far = camera.get_clip_far_tween().interpolate(context->alpha);
@@ -266,6 +251,11 @@ void shadow_map_pass::set_split_scheme_weight(float weight)
 	split_scheme_weight = weight;
 }
 
+void shadow_map_pass::set_light(const directional_light* light)
+{
+	this->light = light;
+}
+
 bool operation_compare(const render_operation& a, const render_operation& b)
 {
 	// Determine transparency
diff --git a/src/renderer/passes/shadow-map-pass.hpp b/src/renderer/passes/shadow-map-pass.hpp
index db6326e..3768b51 100644
--- a/src/renderer/passes/shadow-map-pass.hpp
+++ b/src/renderer/passes/shadow-map-pass.hpp
@@ -27,6 +27,7 @@ class shader_program;
 class shader_input;
 class camera;
 class resource_manager;
+class directional_light;
 
 /**
  *
@@ -45,6 +46,8 @@ public:
 	 */
 	void set_split_scheme_weight(float weight);
 	
+	void set_light(const directional_light* light);
+	
 	const float4x4* get_shadow_matrices() const;
 	const float* get_split_distances() const;
 
@@ -70,6 +73,7 @@ private:
 	mutable float4x4 shadow_matrices[4];
 	float4x4 bias_tile_matrices[4];
 	float split_scheme_weight;
+	const directional_light* light;
 };
 
 inline const float4x4* shadow_map_pass::get_shadow_matrices() const
diff --git a/src/renderer/passes/sky-pass.cpp b/src/renderer/passes/sky-pass.cpp
index e1c0f81..db69438 100644
--- a/src/renderer/passes/sky-pass.cpp
+++ b/src/renderer/passes/sky-pass.cpp
@@ -44,7 +44,8 @@
 sky_pass::sky_pass(::rasterizer* rasterizer, const ::framebuffer* framebuffer, resource_manager* resource_manager):
 	render_pass(rasterizer, framebuffer),
 	sky_palette(nullptr),
-	mouse_position({0.0f, 0.0f})
+	mouse_position({0.0f, 0.0f}),
+	sun_light(nullptr)
 {
 	shader_program = resource_manager->load<::shader_program>("sky.glsl");
 	matrix_input = shader_program->get_input("matrix");
@@ -57,6 +58,7 @@ sky_pass::sky_pass(::rasterizer* rasterizer, const ::framebuffer* framebuffer, r
 	sky_palette_input = shader_program->get_input("sky_palette");
 	mouse_input = shader_program->get_input("mouse");
 	resolution_input = shader_program->get_input("resolution");
+	time_input = shader_program->get_input("time");
 
 	const float vertex_data[] =
 	{
@@ -95,20 +97,13 @@ void sky_pass::render(render_context* context) const
 	auto viewport = framebuffer->get_dimensions();
 	rasterizer->set_viewport(0, 0, std::get<0>(viewport), std::get<1>(viewport));
 	
+	float time = (time_tween) ? time_tween->interpolate(context->alpha) : 0.0f;
 	float2 resolution = {static_cast<float>(std::get<0>(viewport)), static_cast<float>(std::get<1>(viewport))};
+	float3 sun_direction = {0, -1, 0};
 	
-	// Find sun direction
-	float3 sun_direction = {0, 0, -1};
-	const std::list<scene_object_base*>* lights = context->scene->get_objects(light::object_type_id);
-	for (const scene_object_base* object: *lights)
+	if (sun_light)
 	{
-		const ::light* light = static_cast<const ::light*>(object);
-		
-		if (light->get_light_type() == light_type::directional)
-		{
-			sun_direction = static_cast<const directional_light*>(light)->get_direction_tween().interpolate(context->alpha);
-			break;
-		}
+		sun_direction = sun_light->get_direction_tween().interpolate(context->alpha);
 	}
 
 	// Calculate matrix
@@ -138,6 +133,8 @@ void sky_pass::render(render_context* context) const
 		mouse_input->upload(mouse_position);
 	if (resolution_input)
 		resolution_input->upload(resolution);
+	if (time_input)
+		time_input->upload(time);
 	
 	// Draw quad
 	rasterizer->draw_arrays(*quad_vao, drawing_mode::triangles, 0, 6);
@@ -163,11 +160,21 @@ void sky_pass::set_zenith_color(const float3& color)
 	zenith_color = color;
 }
 
+void sky_pass::set_sun_light(const directional_light* light)
+{
+	sun_light = light;
+}
+
 void sky_pass::set_sky_palette(const texture_2d* texture)
 {
 	sky_palette = texture;
 }
 
+void sky_pass::set_time_tween(const tween<double>* time)
+{
+	this->time_tween = time;
+}
+
 void sky_pass::handle_event(const mouse_moved_event& event)
 {
 	mouse_position = {static_cast<float>(event.x), static_cast<float>(event.y)};
diff --git a/src/renderer/passes/sky-pass.hpp b/src/renderer/passes/sky-pass.hpp
index 9250e74..e610b93 100644
--- a/src/renderer/passes/sky-pass.hpp
+++ b/src/renderer/passes/sky-pass.hpp
@@ -24,6 +24,7 @@
 #include "utility/fundamental-types.hpp"
 #include "event/event-handler.hpp"
 #include "event/input-events.hpp"
+#include "animation/tween.hpp"
 
 class shader_program;
 class shader_input;
@@ -31,6 +32,7 @@ class vertex_buffer;
 class vertex_array;
 class texture_2d;
 class resource_manager;
+class directional_light;
 
 /**
  *
@@ -47,7 +49,9 @@ public:
 	void set_sun_color(const float3& color);
 	void set_horizon_color(const float3& color);
 	void set_zenith_color(const float3& color);
+	void set_sun_light(const directional_light* direction);
 	void set_sky_palette(const texture_2d* texture);
+	void set_time_tween(const tween<double>* time);
 
 private:
 	virtual void handle_event(const mouse_moved_event& event);
@@ -62,6 +66,7 @@ private:
 	const shader_input* sky_palette_input;
 	const shader_input* mouse_input;
 	const shader_input* resolution_input;
+	const shader_input* time_input;
 
 	vertex_buffer* quad_vbo;
 	vertex_array* quad_vao;
@@ -70,8 +75,10 @@ private:
 	float3 sun_color;
 	float3 horizon_color;
 	float3 zenith_color;
+	const directional_light* sun_light;
 	const texture_2d* sky_palette;
 	float2 mouse_position;
+	const tween<double>* time_tween;
 };
 
 #endif // ANTKEEPER_SKY_PASS_HPP