1 files changed, 118 insertions, 0 deletions
diff --git a/src/engine/engine.h b/src/engine/engine.h
new file mode 100644
index 0000000..6f90efb
--- /dev/null
+++ b/src/engine/engine.h
@@ -0,0 +1,118 @@
+#pragma once
+
+#include <vector>
+#include <iostream>
+#include <GLFW/glfw3.h>
+#include <glm/glm.hpp>
+#include <glm/gtc/matrix_transform.hpp>
+#include <glm/gtc/type_ptr.hpp>
+#include <fstream>
+#include <sstream>
+#include <chrono>
+#include <cmath>
+
+#include "core/application.h"
+#include "core/camera.h"
+#include "rendering/renderer.h"
+#include "rendering/shader.h"
+#include "rendering/texture.h"
+#include "rendering/vertex_array.h"
+#include "rendering/uniform_buffer.h"
+
+namespace Donut
+{
+    const double c = 299792458.0;
+    const double G = 6.67430e-11;
+
+    struct BlackHole 
+    {
+        glm::vec3 m_position;
+        double m_mass;
+        double m_radius;
+        double m_rs;
+
+        BlackHole(glm::vec3 pos, float mass) 
+            : m_position(pos),
+              m_mass(mass) 
+        {
+            m_rs = 2.0 * G * m_mass / (c * c);
+        }
+
+        bool intercept(float px, float py, float pz) const 
+        {
+            double dx = double(px) - double(m_position.x);
+            double dy = double(py) - double(m_position.y);
+            double dz = double(pz) - double(m_position.z);
+            double dist2 = dx * dx + dy * dy + dz * dz;
+            return dist2 < m_rs * m_rs;
+        }
+    };
+
+    struct ObjectData 
+    {
+        glm::vec4 m_pos_radius;
+        glm::vec4 m_color;
+        float m_mass;
+        glm::vec3 m_velocity = glm::vec3(0.0f, 0.0f, 0.0f);
+    };
+
+    class Engine
+    {
+    public:
+        Engine();
+        ~Engine() = default;
+
+        void generate_grid(const std::vector<ObjectData>& objects);
+        void draw_grid(const glm::mat4& view_proj);
+        void draw_full_screen_quad();
+        void dispatch_compute(const Camera& cam);
+        void upload_camera_ubo(const Camera& cam);
+        void upload_objects_ubo(const std::vector<ObjectData>& objs);
+        void upload_disk_ubo();
+        void render_scene();
+        void update_physics(float delta_time);
+        void update_window_dimensions();
+
+              Camera& get_camera()       { return m_camera; }
+        const Camera& get_camera() const { return m_camera; }
+        
+        const std::vector<ObjectData>& get_objects() const { return m_objects; }
+              std::vector<ObjectData>& get_objects()       { return m_objects; }
+        
+        bool get_gravity() const       { return m_gravity;    }
+        void set_gravity(bool gravity) { m_gravity = gravity; }
+        
+        int get_width()         const { return m_width;         }
+        int get_height()        const { return m_height;        }
+        int get_compute_width()  const { return m_compute_width;  }
+        int get_compute_height() const { return m_compute_height; }
+
+    private:
+        std::string create_basic_vertex_shader();
+        std::string create_basic_fragment_shader();
+        std::string load_compute_shader(const std::string& path);
+    private:
+        Ref<Shader>        m_grid_shader;
+        Ref<Shader>        m_quad_shader;
+        Ref<Shader>        m_compute_shader;
+        Ref<Texture2D>     m_texture;
+        Ref<VertexArray>   m_quad_vao;
+        Ref<VertexArray>   m_grid_vao;
+        Ref<UniformBuffer> m_camera_ubo;
+        Ref<UniformBuffer> m_disk_ubo;
+        Ref<UniformBuffer> m_objects_ubo;
+        
+        int   m_grid_index_count = 0;
+        int   m_width;
+        int   m_height;
+        int   m_compute_width;
+        int   m_compute_height;
+        float m_width_scale = 100000000000.0f;
+        float m_height_scale = 75000000000.0f;
+
+        std::vector<ObjectData> m_objects;
+        BlackHole               m_sag_a;
+        Camera                  m_camera;
+        bool                    m_gravity = false;
+    };
+}