1 files changed, 106 insertions, 0 deletions
diff --git a/src/crepe/system/PhysicsSystem.cpp b/src/crepe/system/PhysicsSystem.cpp
new file mode 100644
index 0000000..62f8132
--- /dev/null
+++ b/src/crepe/system/PhysicsSystem.cpp
@@ -0,0 +1,106 @@
+#include <cmath>
+
+#include "../api/Config.h"
+#include "../api/Rigidbody.h"
+#include "../api/Transform.h"
+#include "../api/Vector2.h"
+#include "../manager/ComponentManager.h"
+#include "../manager/LoopTimerManager.h"
+#include "../manager/Mediator.h"
+
+#include "PhysicsSystem.h"
+
+using namespace crepe;
+
+void PhysicsSystem::fixed_update() {
+	const Mediator & mediator = this->mediator;
+	ComponentManager & mgr = mediator.component_manager;
+	LoopTimerManager & loop_timer = mediator.loop_timer;
+	RefVector<Rigidbody> rigidbodies = mgr.get_components_by_type<Rigidbody>();
+	float dt = loop_timer.get_scaled_fixed_delta_time().count();
+
+	float gravity = Config::get_instance().physics.gravity;
+	for (Rigidbody & rigidbody : rigidbodies) {
+		if (!rigidbody.active) continue;
+		Transform & transform
+			= mgr.get_components_by_id<Transform>(rigidbody.game_object_id).front().get();
+
+		switch (rigidbody.data.body_type) {
+			case Rigidbody::BodyType::DYNAMIC:
+				if (transform.game_object_id == rigidbody.game_object_id) {
+					// Add gravity
+
+					if (rigidbody.data.mass <= 0) {
+						throw std::runtime_error("Mass must be greater than 0");
+					}
+
+					if (gravity <= 0) {
+						throw std::runtime_error("Config Gravity must be greater than 0");
+					}
+
+					if (rigidbody.data.gravity_scale > 0 && !rigidbody.data.constraints.y) {
+						rigidbody.data.linear_velocity.y
+							+= (rigidbody.data.mass * rigidbody.data.gravity_scale * gravity
+								* dt);
+					}
+					// Add coefficient rotation
+					if (rigidbody.data.angular_velocity_coefficient > 0) {
+						rigidbody.data.angular_velocity
+							*= std::pow(rigidbody.data.angular_velocity_coefficient, dt);
+					}
+
+					// Add coefficient movement horizontal
+					if (rigidbody.data.linear_velocity_coefficient.x > 0
+						&& !rigidbody.data.constraints.x) {
+						rigidbody.data.linear_velocity.x
+							*= std::pow(rigidbody.data.linear_velocity_coefficient.x, dt);
+					}
+
+					// Add coefficient movement horizontal
+					if (rigidbody.data.linear_velocity_coefficient.y > 0
+						&& !rigidbody.data.constraints.y) {
+						rigidbody.data.linear_velocity.y
+							*= std::pow(rigidbody.data.linear_velocity_coefficient.y, dt);
+					}
+
+					// Max velocity check
+					if (rigidbody.data.angular_velocity
+						> rigidbody.data.max_angular_velocity) {
+						rigidbody.data.angular_velocity = rigidbody.data.max_angular_velocity;
+					} else if (rigidbody.data.angular_velocity
+							   < -rigidbody.data.max_angular_velocity) {
+						rigidbody.data.angular_velocity = -rigidbody.data.max_angular_velocity;
+					}
+
+					// Set max velocity to maximum length
+					if (rigidbody.data.linear_velocity.length()
+						> rigidbody.data.max_linear_velocity) {
+						rigidbody.data.linear_velocity.normalize();
+						rigidbody.data.linear_velocity *= rigidbody.data.max_linear_velocity;
+					}
+
+					// Move object
+					if (!rigidbody.data.constraints.rotation) {
+						transform.rotation += rigidbody.data.angular_velocity * dt;
+						transform.rotation = std::fmod(transform.rotation, 360.0);
+						if (transform.rotation < 0) {
+							transform.rotation += 360.0;
+						}
+					}
+					if (!rigidbody.data.constraints.x) {
+						transform.position.x += rigidbody.data.linear_velocity.x * dt;
+					}
+					if (!rigidbody.data.constraints.y) {
+						transform.position.y += rigidbody.data.linear_velocity.y * dt;
+					}
+				}
+				break;
+			case Rigidbody::BodyType::KINEMATIC:
+				break; //(scripts)
+			case Rigidbody::BodyType::STATIC:
+				break; //(unmoveable objects)
+			default:
+				break;
+		}
+	}
+}