[Book 1, Chapter 10] Shadows and reflections do not appear after adding the material class.

[sapientsand]

Hello. I'm not sure what I'm doing wrong, but after I added the material class to my program, there aren't any shadows in my output images. I'm not exactly sure what I'm missing here, but I'll attach image and a link to my code below to see if someone more competent than I am can figure out what I've done wrong. My code in question: https://github.com/sapientsand/rtinoneweekend

[whydoubt]

I suspect there may be more differences, but at the least, in the metal class, the line

vec3 reflected = unit_vector(reflected) + (fuzz * random_unit_vector());

does not match the book.