Prior to ray tracing, we generated a bounding box structure using two 3-dimensional points.

The two points represent rear-leftmost-lower point & front-rightmost-upper corners of the bounding box. These points enabled us to shift x, y, and z coordinates to obtain the remaining 6 corners (total of 8).

Given the 8 corners, we were able to generate 12 lines outlining our volume using GL_LINES primitive (please see thin orange outline). Then, from the same points, we generated 12 triangles representing our bounding volume planes (please see light blue & 50% transparent walls). These were done using GL_TRIANGLES primitive.

Lastly we have added three sliders to our GUI in order to manipulate the bounding box: length x, length y, and length z. These simple parameters allow us to easily resize the bounding box volume in three dimensions.