Runtime error when compile with latest V

[JalonSolov]

Simple enough to update the code to latest V: Run v fmt -w . in the directory to take care of all the warnings (due to changes in V), and add a return vec3.Vec{} at the end of random_point_in_sphere (that fn should probably be refactored a bit, but this made it compile).

However, when I tried to run it, all I got was this:

[jamie@5950x vraytracer]$ bin/raytrace >output.ppm
Killed
[jamie@5950x vraytracer]$

I didn't hit Ctrl-C or anything, it just stopped on it's own with that message.