Octree scene integration

In order to benefit from the Octree, we must integrate it with the scene as an acceleration structure. The OctreeNode structure and its helper functions should not be used outside of the Scene class.

Getting ready

First, we are going to modify the Scene class to hold an Octree. This means dealing with some dynamic memory, so we also need to add a destructor. The copy constructor and assignment operator will be disabled. If an acceleration structure is present, we should forward operations such as raycasting to the accelerator. Of course, the original code needs to stay in place as the acceleration structure is optional.

How to do it…

Follow these steps to integrate the octree into the scene:

1. Modify the Scene class declared in Scene.h. Add an OctreeNode pointer to serve as the root node of the Octree. Set this pointer to null in the default constructor. The destructor should free this memory if it is allocated. Also, we need to declare the Accelerate helper function...