Adding model loading and bvh generation

src/scene/AABB.h

@@ -0,0 +1,38 @@
+#pragma once
+#include <glm/vec3.hpp>
+#include <utility>
+
+struct AABB
+{
+    glm::vec3 min = glm::vec3(std::numeric_limits<float>::max());
+    glm::vec3 max = glm::vec3(std::numeric_limits<float>::lowest());
+    float surfaceArea() const
+    {
+        glm::vec3 d = glm::vec3(max.x - min.x, max.y - min.y, max.z - min.z);
+        return 2.0f * (d.x * d.y + d.y * d.z + d.z * d.x);
+    }
+    void adjust(glm::vec3 pos)
+    {
+        min.x = std::min(min.x, pos.x);
+        min.y = std::min(min.y, pos.y);
+        min.z = std::min(min.z, pos.z);
+
+        max.x = std::max(max.x, pos.x);
+        max.y = std::max(max.y, pos.y);
+        max.z = std::max(max.z, pos.z);
+    }
+    static AABB combine(AABB lhs, AABB rhs)
+    {
+        AABB result;
+
+        result.min.x = std::min(lhs.min.x, rhs.min.x);
+        result.min.y = std::min(lhs.min.y, rhs.min.y);
+        result.min.z = std::min(lhs.min.z, rhs.min.z);
+
+        result.max.x = std::max(lhs.max.x, rhs.max.x);
+        result.max.y = std::max(lhs.max.y, rhs.max.y);
+        result.max.z = std::max(lhs.max.z, rhs.max.z);
+
+        return result;
+    }
+};