Ch 11 Reflection / Refraction Problem

Thank you Jamis I finally found out what was the issue, since you told me that the problem might be with the intersection between the sphere and the checkered Plane,
I checked out the Plane and I realized that I was doing one of the mistakes that you warn us about:

so basically I was doing the transform multiplication in the wrong order it was like this:

rotation_x(pi/2) * translationMatrix(0, 0, 10)

i changed it like this:

translationMatrix(0, 0, 10) * rotation_x(pi/2)

and I got this finally: 



I think this might be it this time.

thanks again,

for anyone who had the same problem as mine ,
just follow this 2 steps:
1. pass all the intersections even those inferior to zero in you Intersect_world function. as tdaines and Jamis mentioned
2.check your Plane transformation if the order of your multiplication is correct.
 that should do the work, and sorry for my English still learning