1 files changed, 70 insertions, 0 deletions
diff --git a/src/engine/scene.h b/src/engine/scene.h
new file mode 100644
index 0000000..4b41203
--- /dev/null
+++ b/src/engine/scene.h
@@ -0,0 +1,70 @@
+#pragma once
+
+#include <vector>
+#include <limits>
+
+#include "object.h"
+
+namespace Donut
+{
+    class Scene
+    {
+    public:
+        Scene()
+            : m_light_pos(5.0f, 5.0f, 5.0f) { }
+
+        auto trace(Ray& ray) -> glm::vec3
+        {
+            float closest = std::numeric_limits<float>::infinity();
+            const Object* hit_obj = nullptr;
+
+            for (auto& obj : objs)
+            {
+                float t;
+
+                if (obj.intersect(ray, t))
+                    if (t < closest)
+                    {
+                        closest = t;
+                        hit_obj = &obj;
+                    }
+            }
+
+            if (hit_obj)
+            {
+                glm::vec3 hit_point = ray.m_origin + ray.m_direction * closest;
+                glm::vec3 normal = hit_obj->get_normal(hit_point);
+                glm::vec3 light_dir = glm::normalize(m_light_pos - hit_point);
+
+                float diff = std::max(glm::dot(normal, light_dir), 0.0f);
+
+                Ray shadow_ray(hit_point + normal * 0.001f, light_dir);
+                bool in_shadow = false;
+
+                for (auto& obj : objs)
+                {
+                    float t;
+
+                    if (obj.intersect(shadow_ray, t))
+                    {
+                        in_shadow = true;
+                        break;
+                    }
+                }
+
+                glm::vec3 color = hit_obj->m_material.m_color;
+                float ambient = 0.1f;
+
+                if (in_shadow)
+                    return color * ambient;
+                return color * (ambient + diff * 0.9f);
+            }
+
+            return glm::vec3(0.0f, 0.0f, 0.1f);
+        }
+
+    public:
+        std::vector<Object> objs;
+        glm::vec3 m_light_pos;
+    };
+};