17 files changed, 504 insertions, 9 deletions

diff --git a/src/crepe/Collider.cpp b/src/crepe/Collider.cpp
index bbec488..0706371 100644
--- a/src/crepe/Collider.cpp
+++ b/src/crepe/Collider.cpp
@@ -2,4 +2,4 @@
 
 using namespace crepe;
 
-Collider::Collider(game_object_id_t id) : Component(id) {}
+Collider::Collider(game_object_id_t id, Vector2 offset) : Component(id), offset(offset) {}
diff --git a/src/crepe/Collider.h b/src/crepe/Collider.h
index 827f83d..54695b1 100644
--- a/src/crepe/Collider.h
+++ b/src/crepe/Collider.h
@@ -1,14 +1,14 @@
 #pragma once
 
 #include "Component.h"
+#include "api/Vector2.h"
 
 namespace crepe {
 
 class Collider : public Component {
 public:
-	Collider(game_object_id_t id);
-
-	int size;
+	Collider(game_object_id_t id, Vector2 offset);
+	Vector2 offset;
 };
 
 } // namespace crepe
diff --git a/src/crepe/api/BoxCollider.cpp b/src/crepe/api/BoxCollider.cpp
new file mode 100644
index 0000000..eafbdb2
--- /dev/null
+++ b/src/crepe/api/BoxCollider.cpp
@@ -0,0 +1,7 @@
+#include "BoxCollider.h"
+#include "../Collider.h" 
+
+using namespace crepe;
+
+
+BoxCollider::BoxCollider(game_object_id_t game_object_id,Vector2 offset, double width, double height) : Collider(game_object_id,offset), width(width), height(height) {}
diff --git a/src/crepe/api/BoxCollider.h b/src/crepe/api/BoxCollider.h
new file mode 100644
index 0000000..357c979
--- /dev/null
+++ b/src/crepe/api/BoxCollider.h
@@ -0,0 +1,15 @@
+#pragma once
+
+#include "Vector2.h"
+#include "../Collider.h"
+
+namespace crepe {
+
+class BoxCollider : public Collider {
+public:
+	BoxCollider(game_object_id_t game_object_id,Vector2 offset, double width, double height);
+	double width;
+	double height;
+};
+
+} // namespace crepe
diff --git a/src/crepe/api/CMakeLists.txt b/src/crepe/api/CMakeLists.txt
index 53b3041..07341e2 100644
--- a/src/crepe/api/CMakeLists.txt
+++ b/src/crepe/api/CMakeLists.txt
@@ -18,6 +18,8 @@ target_sources(crepe PUBLIC
 	Vector2.cpp
 	Camera.cpp
 	Animator.cpp
+	BoxCollider.cpp
+	CircleCollider.cpp
 	EventManager.cpp
 	EventHandler.cpp
 	IKeyListener.cpp
@@ -48,6 +50,8 @@ target_sources(crepe PUBLIC FILE_SET HEADERS FILES
 	SceneManager.hpp
 	Camera.h
 	Animator.h
+	BoxCollider.h
+	CircleCollider.h
 	EventManager.h
 	EventManager.hpp
 	EventHandler.h
diff --git a/src/crepe/api/CircleCollider.cpp b/src/crepe/api/CircleCollider.cpp
new file mode 100644
index 0000000..04a4995
--- /dev/null
+++ b/src/crepe/api/CircleCollider.cpp
@@ -0,0 +1,6 @@
+#include "CircleCollider.h"
+
+using namespace crepe;
+
+
+CircleCollider::CircleCollider(game_object_id_t game_object_id,Vector2 offset, int radius) : Collider(game_object_id,offset), radius(radius) {}
diff --git a/src/crepe/api/CircleCollider.h b/src/crepe/api/CircleCollider.h
index e77a592..29a9c1e 100644
--- a/src/crepe/api/CircleCollider.h
+++ b/src/crepe/api/CircleCollider.h
@@ -1,14 +1,15 @@
 #pragma once
+
+#include "Vector2.h"
+
 #include "../Collider.h"
 
 namespace crepe {
 
 class CircleCollider : public Collider {
 public:
-	CircleCollider(game_object_id_t game_object_id, int radius)
-		: Collider(game_object_id),
-		  radius(radius) {}
-	int radius;
+	CircleCollider(game_object_id_t game_object_id,Vector2 offset, int radius);
+	double radius;
 };
 
 } // namespace crepe
diff --git a/src/crepe/api/Rigidbody.h b/src/crepe/api/Rigidbody.h
index 68481f4..b9edec2 100644
--- a/src/crepe/api/Rigidbody.h
+++ b/src/crepe/api/Rigidbody.h
@@ -75,6 +75,8 @@ public:
 		bool use_gravity = true;
 		//! if object bounces
 		bool bounce = false;
+		//! offset of all colliders
+		Vector2 offset;
 	};
 
 public:
diff --git a/src/crepe/api/Vector2.cpp b/src/crepe/api/Vector2.cpp
index 09b3fa3..947c49e 100644
--- a/src/crepe/api/Vector2.cpp
+++ b/src/crepe/api/Vector2.cpp
@@ -54,4 +54,8 @@ bool Vector2::operator!=(const Vector2 & other) const {
 	return !(*this == other);
 }
 
+double Vector2::dot(const Vector2& other) const {
+	return this->x * other.x + this->y * other.y;
+}
+
 } // namespace crepe
diff --git a/src/crepe/api/Vector2.h b/src/crepe/api/Vector2.h
index 5a57484..90d9d57 100644
--- a/src/crepe/api/Vector2.h
+++ b/src/crepe/api/Vector2.h
@@ -42,6 +42,9 @@ public:
 
 	//! Checks if this vector is not equal to another vector.
 	bool operator!=(const Vector2 & other) const;
+
+	//!
+	double dot(const Vector2& other) const;
 };
 
 } // namespace crepe
diff --git a/src/crepe/system/CollisionSystem.cpp b/src/crepe/system/CollisionSystem.cpp
index 55e0fdc..ac35026 100644
--- a/src/crepe/system/CollisionSystem.cpp
+++ b/src/crepe/system/CollisionSystem.cpp
@@ -1,7 +1,280 @@
+#include <cmath>
+#include <algorithm>
+#include <cstddef>
+#include <tuple>
+#include <utility>
+#include <variant>
+
 #include "CollisionSystem.h"
 
+#include "../ComponentManager.h"
+#include "../api/BoxCollider.h"
+#include "../api/CircleCollider.h"
+#include "../api/Vector2.h"
+#include "../api/Rigidbody.h"
+#include "../api/Transform.h"
+
+#include "Collider.h"
+#include "iostream"
+
 using namespace crepe;
 
 CollisionSystem::CollisionSystem() {}
 
-void CollisionSystem::update() {}
+void CollisionSystem::update() {
+	ComponentManager & mgr = ComponentManager::get_instance();
+	std::vector<std::reference_wrapper<BoxCollider>> boxcolliders	= mgr.get_components_by_type<BoxCollider>();
+	std::vector<std::reference_wrapper<CircleCollider>> circlecolliders	= mgr.get_components_by_type<CircleCollider>();
+	std::vector<std::pair<CollidedInfoStor,CollidedInfoStor>> collided = check_collisions(boxcolliders,circlecolliders);
+	std::cout << "DEBUG INFO" << std::endl;
+	for (const auto& collision_pair : collided) {
+		call_collision_handler(collision_pair.first,collision_pair.second); // First collider
+		call_collision_handler(collision_pair.second,collision_pair.first); // First collider
+	}
+
+	if(collided.empty()) {
+		std::cout << "No objects collided" << std::endl;
+	}
+}
+
+void CollisionSystem::call_collision_handler(const CollidedInfoStor& data1,const CollidedInfoStor& data2){
+
+	// Check collision type and get values for handler
+	game_object_id_t first = 0,second = 0;
+	if (std::holds_alternative<BoxCollider>(data1.collider)) {
+		if (std::holds_alternative<BoxCollider>(data2.collider)) {
+			const BoxCollider& box_collider1 = std::get<BoxCollider>(data1.collider);
+			const BoxCollider& box_collider2 = std::get<BoxCollider>(data2.collider);
+			first = box_collider1.game_object_id;
+			second = box_collider2.game_object_id;
+		}
+		else {
+			const BoxCollider& box_collider = std::get<BoxCollider>(data1.collider);
+			const CircleCollider& circle_collider = std::get<CircleCollider>(data2.collider);
+			first = box_collider.game_object_id;
+			second = circle_collider.game_object_id;
+		}
+	}
+	else {
+		if (std::holds_alternative<CircleCollider>(data2.collider)) {
+			const CircleCollider& circle_collider1 = std::get<CircleCollider>(data1.collider);
+			const CircleCollider& circle_collider2 = std::get<CircleCollider>(data2.collider);
+			first = circle_collider1.game_object_id;
+			second = circle_collider2.game_object_id;
+		}
+		else {
+			const CircleCollider& circle_collider = std::get<CircleCollider>(data1.collider);
+			const BoxCollider& box_collider = std::get<BoxCollider>(data2.collider);
+			first = circle_collider.game_object_id;
+			second = box_collider.game_object_id;
+		}
+	}
+
+	// check rigidbody type
+	if(data1.rigidbody.data.body_type != Rigidbody::BodyType::STATIC)
+	{
+		// If second body is static move back
+		if(data2.rigidbody.data.body_type == Rigidbody::BodyType::STATIC) return; 
+		//call static handler (is bounce true?)
+
+		// call script handler
+	}		
+}
+
+std::vector<std::pair<CollisionSystem::CollidedInfoStor,CollisionSystem::CollidedInfoStor>> CollisionSystem::check_collisions(const std::vector<std::reference_wrapper<BoxCollider>>& boxcolliders, const std::vector<std::reference_wrapper<CircleCollider>>& circlecolliders) {
+	ComponentManager & mgr = ComponentManager::get_instance();
+	std::vector<std::pair<CollidedInfoStor,CollidedInfoStor>> collisions_ret;
+	//if no colliders skip
+	//check if colliders has rigibocdy if not skip
+
+	//if amount is higer than lets say 16 for now use quadtree otwerwise skip
+	//quadtree code
+	//quadtree is placed over the input vector
+
+	// Check collisions
+	for (size_t i = 0; i < boxcolliders.size(); ++i) {
+		// Fetch components for the first box collider
+		if(!boxcolliders[i].get().active) continue;
+		int game_object_id_1 = boxcolliders[i].get().game_object_id;
+		Transform& transform1 = mgr.get_components_by_id<Transform>(game_object_id_1).front().get();
+		if(!transform1.active) continue;
+		Rigidbody& rigidbody1 = mgr.get_components_by_id<Rigidbody>(game_object_id_1).front().get();
+		if(!rigidbody1.active) continue;
+		
+		// Check CircleCollider vs CircleCollider
+		for (size_t j = i + 1; j < boxcolliders.size(); ++j) {
+			if(!boxcolliders[j].get().active) continue;
+			// Skip self collision
+			int game_object_id_2 = boxcolliders[j].get().game_object_id;
+			if (game_object_id_1 == game_object_id_2) continue;
+
+			// Fetch components for the second box collider
+			Transform & transform2 = mgr.get_components_by_id<Transform>(boxcolliders[j].get().game_object_id).front().get();
+			if(!transform2.active) continue;
+			Rigidbody & rigidbody2 = mgr.get_components_by_id<Rigidbody>(boxcolliders[j].get().game_object_id).front().get();
+			if(!rigidbody2.active) continue;
+			// Check collision
+			if (check_box_box_collision(boxcolliders[i], boxcolliders[j], transform1, transform2, rigidbody1, rigidbody2)) {
+				collisions_ret.emplace_back(std::make_pair(
+				CollidedInfoStor{boxcolliders[i], transform1, rigidbody1}, 
+				CollidedInfoStor{boxcolliders[j], transform2, rigidbody2}
+				));
+			}
+		}
+
+		// Check BoxCollider vs CircleCollider
+		for (size_t j = 0; j < circlecolliders.size(); ++j) {
+			if(!circlecolliders[j].get().active) continue;
+			// Skip self collision
+			int game_object_id_2 = circlecolliders[j].get().game_object_id;
+			if (game_object_id_1 == game_object_id_2) continue;
+
+			// Fetch components for the second collider (circle)
+			Transform & transform2 = mgr.get_components_by_id<Transform>(circlecolliders[j].get().game_object_id).front().get();
+			if(!transform2.active) continue;
+			Rigidbody & rigidbody2 = mgr.get_components_by_id<Rigidbody>(circlecolliders[j].get().game_object_id).front().get();
+			if(!rigidbody2.active) continue;
+
+			// Check collision
+			if (check_box_circle_collision(boxcolliders[i], circlecolliders[j], transform1, transform2, rigidbody1, rigidbody2)) {
+				
+				collisions_ret.emplace_back(std::make_pair(
+				CollidedInfoStor{boxcolliders[i], transform1, rigidbody1}, 
+				CollidedInfoStor{circlecolliders[j], transform2, rigidbody2}
+				));
+			}
+		}
+	}
+	// Check CircleCollider vs CircleCollider
+	for (size_t i = 0; i < circlecolliders.size(); ++i) {
+		if(!circlecolliders[i].get().active) continue;
+		// Fetch components for the first circle collider
+		int game_object_id_1 = circlecolliders[i].get().game_object_id;
+		Transform & transform1 = mgr.get_components_by_id<Transform>(circlecolliders[i].get().game_object_id).front().get();
+		if(!transform1.active) continue;
+		Rigidbody & rigidbody1 = mgr.get_components_by_id<Rigidbody>(circlecolliders[i].get().game_object_id).front().get();
+		if(!rigidbody1.active) continue;
+
+		for (size_t j = i + 1; j < circlecolliders.size(); ++j) {
+			if(!circlecolliders[j].get().active) continue;
+			// Skip self collision
+			int game_object_id_2 = circlecolliders[j].get().game_object_id;
+			if (game_object_id_1 == game_object_id_2) continue;
+
+			// Fetch components for the second circle collider
+			Transform & transform2 = mgr.get_components_by_id<Transform>(circlecolliders[j].get().game_object_id).front().get();
+			if(!transform2.active) continue;
+			Rigidbody & rigidbody2 = mgr.get_components_by_id<Rigidbody>(circlecolliders[j].get().game_object_id).front().get();
+			if(!rigidbody2.active) continue;
+
+			// Check collision
+			if (check_circle_circle_collision(circlecolliders[i], circlecolliders[j], transform1, transform2, rigidbody1, rigidbody2)) {
+				collisions_ret.emplace_back(std::make_pair(
+				CollidedInfoStor{circlecolliders[i], transform1, rigidbody1}, 
+				CollidedInfoStor{circlecolliders[j], transform2, rigidbody2}
+				));
+			}
+		}
+	}
+	return collisions_ret;
+}
+
+bool CollisionSystem::check_box_box_collision(const BoxCollider& box1, const BoxCollider& box2, const Transform& transform1, const Transform& transform2, const Rigidbody& rigidbody1, const Rigidbody& rigidbody2)
+{
+	// Get current positions of colliders
+	Vector2 final_position1 = current_position(box1,transform1,rigidbody1);
+	Vector2 final_position2 = current_position(box2,transform2,rigidbody2);
+
+	 // Log final positions for debugging purposes
+	std::cout << "Final Position of Box 1: (" << final_position1.x << ", " << final_position1.y << ")" << std::endl;
+	std::cout << "Final Position of Box 2: (" << final_position2.x << ", " << final_position2.y << ")" << std::endl;
+
+	// Log rotation values for debugging
+	std::cout << "Rotation of Box 1: " << transform1.rotation << " degrees" << std::endl;
+	std::cout << "Rotation of Box 2: " << transform2.rotation << " degrees" << std::endl;
+
+
+	// Calculate half-extents (half width and half height)
+	double half_width1 = box1.width / 2.0;
+	double half_height1 = box1.height / 2.0;
+	double half_width2 = box2.width / 2.0;
+	double half_height2 = box2.height / 2.0;
+
+	// Check if the boxes overlap along the X and Y axes
+	return !(final_position1.x + half_width1 < final_position2.x - half_width2 ||  // box1 is left of box2
+						final_position1.x - half_width1 > final_position2.x + half_width2 ||  // box1 is right of box2
+						final_position1.y + half_height1 < final_position2.y - half_height2 || // box1 is above box2
+						final_position1.y - half_height1 > final_position2.y + half_height2);  // box1 is below box2
+}
+
+bool CollisionSystem::check_box_circle_collision(const BoxCollider& box1, const CircleCollider& circle2, const Transform& transform1, const Transform& transform2, const Rigidbody& rigidbody1, const Rigidbody& rigidbody2) {
+	// Get current positions of colliders
+	Vector2 final_position1 = current_position(box1, transform1, rigidbody1);
+	Vector2 final_position2 = current_position(circle2, transform2, rigidbody2);
+
+	// Log final positions for debugging purposes
+	std::cout << "Final Position of Box: (" << final_position1.x << ", " << final_position1.y << ")" << std::endl;
+	std::cout << "Final Position of Circle: (" << final_position2.x << ", " << final_position2.y << ")" << std::endl;
+
+	// Calculate box half-extents
+	double half_width = box1.width / 2.0;
+	double half_height = box1.height / 2.0;
+
+	// Find the closest point on the box to the circle's center
+	double closest_x = std::max(final_position1.x - half_width, std::min(final_position2.x, final_position1.x + half_width));
+	double closest_y = std::max(final_position1.y - half_height, std::min(final_position2.y, final_position1.y + half_height));
+
+
+	// Calculate the distance squared between the circle's center and the closest point on the box
+	double distance_x = final_position2.x - closest_x;
+	double distance_y = final_position2.y - closest_y;
+	double distance_squared = distance_x * distance_x + distance_y * distance_y;
+
+	// Compare distance squared with the square of the circle's radius
+	return distance_squared <= circle2.radius * circle2.radius;
+}
+
+bool CollisionSystem::check_circle_circle_collision(const CircleCollider& circle1, const CircleCollider& circle2, const Transform& transform1, const Transform& transform2, const Rigidbody& rigidbody1, const Rigidbody& rigidbody2) {
+	// Get current positions of colliders
+	Vector2 final_position1 = current_position(circle1,transform1,rigidbody1);
+	Vector2 final_position2 = current_position(circle2,transform2,rigidbody2);
+
+	// Log final positions for debugging purposes
+	std::cout << "Final Position of Circle 1: (" << final_position1.x << ", " << final_position1.y << ")" << std::endl;
+	std::cout << "Final Position of Circle 2: (" << final_position2.x << ", " << final_position2.y << ")" << std::endl;
+
+	// Log rotation values for debugging (circles do not rotate, so this might not be needed for circles)
+	std::cout << "Rotation of Circle 1: " << transform1.rotation << " degrees" << std::endl;
+	std::cout << "Rotation of Circle 2: " << transform2.rotation << " degrees" << std::endl;
+
+	double distance_x = final_position1.x - final_position2.x;
+	double distance_y = final_position1.y - final_position2.y;
+	double distance_squared = distance_x * distance_x + distance_y * distance_y;
+
+	// Calculate the sum of the radii
+	double radius_sum = circle1.radius + circle2.radius;
+
+	// Check if the distance between the centers is less than or equal to the sum of the radii
+	return distance_squared <= radius_sum * radius_sum;
+}
+
+Vector2 CollisionSystem::current_position(const Collider& collider, const Transform& transform, const Rigidbody& rigidbody) {
+	// Function to convert degrees to radians
+	auto degrees_to_radians = [](double degrees) {
+			return degrees * (M_PI / 180.0);
+	};
+
+	// Get the rotation in radians
+	double radians1 = degrees_to_radians(transform.rotation);
+
+	// Calculate total offset with scale
+	Vector2 total_offset = (rigidbody.data.offset + collider.offset) * transform.scale;
+
+	// Rotate
+	double rotated_total_offset_x1 = total_offset.x * cos(radians1) - total_offset.y * sin(radians1);
+	double rotated_total_offset_y1 = total_offset.x * sin(radians1) + total_offset.y * cos(radians1);
+
+	// Final positions considering scaling and rotation
+	return(transform.position + Vector2(rotated_total_offset_x1, rotated_total_offset_y1));
+
+}
diff --git a/src/crepe/system/CollisionSystem.h b/src/crepe/system/CollisionSystem.h
index 1e9f1aa..9a72948 100644
--- a/src/crepe/system/CollisionSystem.h
+++ b/src/crepe/system/CollisionSystem.h
@@ -1,11 +1,36 @@
 #pragma once
 
+#include "Collider.h"
+#include "api/Rigidbody.h"
+#include "api/Transform.h"
+#include "api/BoxCollider.h"
+#include "api/CircleCollider.h"
+#include <tuple>
+#include <vector>
+#include <variant>
+
 namespace crepe {
 
+
 class CollisionSystem {
+private:
+	using collider_stor = std::variant<BoxCollider, CircleCollider>;
+private:
+	struct CollidedInfoStor {
+		collider_stor collider;  // Store either BoxCollider or CircleCollider
+		Transform transform;      // Transform data
+		Rigidbody rigidbody;      // Rigidbody data
+	};
 public:
 	CollisionSystem();
 	void update();
+private:
+	void call_collision_handler(const CollidedInfoStor& data1,const CollidedInfoStor& data2);
+  std::vector<std::pair<CollidedInfoStor,CollidedInfoStor>> check_collisions(const std::vector<std::reference_wrapper<BoxCollider>>& boxcolliders, const std::vector<std::reference_wrapper<CircleCollider>>& circlecolliders);
+	bool check_box_box_collision(const BoxCollider& box1, const BoxCollider& box2, const Transform& transform1, const Transform& transform2, const Rigidbody& rigidbody1, const Rigidbody& rigidbody2);
+	bool check_box_circle_collision(const BoxCollider& box1, const CircleCollider& circle2, const Transform& transform1, const Transform& transform2, const Rigidbody& rigidbody1, const Rigidbody& rigidbody2);
+	bool check_circle_circle_collision(const CircleCollider& circle1, const CircleCollider& circle2, const Transform& transform1, const Transform& transform2, const Rigidbody& rigidbody1, const Rigidbody& rigidbody2);
+	Vector2 current_position(const Collider& collider, const Transform& transform, const Rigidbody& rigidbody);
 };
 
 } // namespace crepe
diff --git a/src/example/CMakeLists.txt b/src/example/CMakeLists.txt
index ddb0262..d2ea926 100644
--- a/src/example/CMakeLists.txt
+++ b/src/example/CMakeLists.txt
@@ -28,6 +28,7 @@ add_example(proxy)
 add_example(db)
 add_example(ecs)
 add_example(scene_manager)
+add_example(collision)
 add_example(events)
 add_example(particles)
 add_example(gameloop)
diff --git a/src/example/collision.cpp b/src/example/collision.cpp
new file mode 100644
index 0000000..e82b493
--- /dev/null
+++ b/src/example/collision.cpp
@@ -0,0 +1,68 @@
+#include "api/BoxCollider.h"
+#include "system/CollisionSystem.h"
+#include <crepe/Component.h>
+#include <crepe/ComponentManager.h>
+#include <crepe/api/GameObject.h>
+#include <crepe/api/Rigidbody.h>
+#include <crepe/api/BoxCollider.h>
+#include <crepe/api/Transform.h>
+#include <crepe/system/PhysicsSystem.h>
+#include <crepe/system/RenderSystem.h>
+#include <crepe/util/log.h>
+
+#include <crepe/api/AssetManager.h>
+#include <crepe/api/Color.h>
+#include <crepe/api/Sprite.h>
+#include <crepe/api/Texture.h>
+#include <crepe/api/Transform.h>
+#include <crepe/api/Vector2.h>
+
+#include <chrono>
+#include <memory>
+
+using namespace crepe;
+using namespace std;
+
+int main(int argc, char * argv[]) {
+	Color color(0, 0, 0, 0);
+
+	GameObject game_object1(0, "Name", "Tag", Vector2{10, 10}, 0, 1);
+	game_object1.add_component<Rigidbody>(Rigidbody::Data{
+		.mass = 1,
+		.gravity_scale = 1,
+		.body_type = Rigidbody::BodyType::DYNAMIC,
+		.constraints = {0, 0, 0},
+		.use_gravity = true,
+		.bounce = false,
+		.offset = {0,0}
+	});
+	game_object1.add_component<BoxCollider>(Vector2{5, 5}, 5, 5);
+	// game_object1.add_component<Sprite>(
+	// make_shared<Texture>("/home/jaro/crepe/asset/texture/img.png"), color,
+	// FlipSettings{true, true});
+	
+
+	GameObject game_object2(1, "Name", "Tag", Vector2{20, 0}, 90, 1);
+	game_object2.add_component<Rigidbody>(Rigidbody::Data{
+		.mass = 1,
+		.gravity_scale = 1,
+		.body_type = Rigidbody::BodyType::DYNAMIC,
+		.constraints = {0, 0, 0},
+		.use_gravity = true,
+		.bounce = false,
+		.offset = {0,0}
+	});
+	game_object2.add_component<BoxCollider>(Vector2{5, 5}, 5, 5);
+	// game_object2.add_component<Sprite>(
+	// make_shared<Texture>("/home/jaro/crepe/asset/texture/img.png"), color,
+	// FlipSettings{true, true});
+
+	CollisionSystem coltest;
+	coltest.update();
+	// auto & sys = crepe::RenderSystem::get_instance();
+	// auto start = std::chrono::steady_clock::now();
+	// while (std::chrono::steady_clock::now() - start < std::chrono::seconds(5)) {
+	// 	sys.update();
+	// }
+	return 0;
+}
diff --git a/src/test/CMakeLists.txt b/src/test/CMakeLists.txt
index acab388..50802de 100644
--- a/src/test/CMakeLists.txt
+++ b/src/test/CMakeLists.txt
@@ -1,6 +1,8 @@
 target_sources(test_main PUBLIC
 	dummy.cpp
 	# audio.cpp
+	PhysicsTest.cpp
+	CollisionTest.cpp
 	# PhysicsTest.cpp
 	ParticleTest.cpp
 )
diff --git a/src/test/CollisionTest.cpp b/src/test/CollisionTest.cpp
new file mode 100644
index 0000000..3e43479
--- /dev/null
+++ b/src/test/CollisionTest.cpp
@@ -0,0 +1,83 @@
+#include "api/BoxCollider.h"
+#include "api/CircleCollider.h"
+#include "api/Vector2.h"
+#include <crepe/ComponentManager.h>
+#include <crepe/api/Config.h>
+#include <crepe/api/GameObject.h>
+#include <crepe/api/Rigidbody.h>
+#include <crepe/api/Transform.h>
+#include <crepe/system/CollisionSystem.h>
+#include <gtest/gtest.h>
+
+using namespace std;
+using namespace std::chrono_literals;
+using namespace crepe;
+
+class CollisionTest : public ::testing::Test {
+protected:
+	GameObject * game_object1;
+	GameObject * game_object2;
+	CollisionSystem collision_system;
+	void SetUp() override {
+		ComponentManager & mgr = ComponentManager::get_instance();
+		mgr.delete_all_components();
+		std::vector<std::reference_wrapper<Transform>> transforms
+			= mgr.get_components_by_id<Transform>(0);
+
+		// ob 1
+		game_object1 = new GameObject(0, "", "", Vector2{0, 0}, 0, 0);
+		game_object1->add_component<Rigidbody>(Rigidbody::Data{
+			.mass = 1,
+			.gravity_scale = 1,
+			.body_type = Rigidbody::BodyType::DYNAMIC,
+			.max_linear_velocity = Vector2{10, 10},
+			.max_angular_velocity = 10,
+			.constraints = {0, 0, 0},
+			.use_gravity = false,
+			.bounce = false,
+		});
+		
+		game_object1->add_component<BoxCollider>(Vector2{0,0},10,10);
+		
+
+		//ob 2
+		game_object2 = new GameObject(1, "", "", Vector2{50, 50}, 0, 0);
+		game_object2->add_component<Rigidbody>(Rigidbody::Data{
+			.mass = 1,
+			.gravity_scale = 1,
+			.body_type = Rigidbody::BodyType::DYNAMIC,
+			.max_linear_velocity = Vector2{10, 10},
+			.max_angular_velocity = 10,
+			.constraints = {0, 0, 0},
+			.use_gravity = false,
+			.bounce = false,
+		});
+		game_object2->add_component<CircleCollider>(Vector2{0,0},5);
+	}
+};
+
+TEST_F(CollisionTest, box_box_collision) {
+	Config::get_instance().physics.gravity = 1;
+	ComponentManager & mgr = ComponentManager::get_instance();
+	std::vector<std::reference_wrapper<Transform>> transforms
+		= mgr.get_components_by_id<Transform>(0);
+	Transform & transform = transforms.front().get();
+	ASSERT_FALSE(transforms.empty());
+	transform.position = {39,50};
+	collision_system.update();
+	transform.position = {40,50};
+	collision_system.update();
+	transform.position = {50,39};
+	collision_system.update();
+	transform.position = {50,40};
+	collision_system.update();
+	transform.position = {50,60};
+	collision_system.update();
+	transform.position = {50,61};
+	collision_system.update();
+	transform.position = {60,50};
+	collision_system.update();
+	transform.position = {61,50};
+	collision_system.update();
+}
+
diff --git a/src/test/PhysicsTest.cpp b/src/test/PhysicsTest.cpp
index 5385962..3332f74 100644
--- a/src/test/PhysicsTest.cpp
+++ b/src/test/PhysicsTest.cpp
@@ -16,6 +16,7 @@ protected:
 	PhysicsSystem physics_system;
 	void SetUp() override {
 		ComponentManager & mgr = ComponentManager::get_instance();
+		mgr.delete_all_components();
 		std::vector<std::reference_wrapper<Transform>> transforms
 			= mgr.get_components_by_id<Transform>(0);
 		if (transforms.empty()) {