Simple fix to avoid error while working with AD

[efmanu]

Modified line 38 in core.jl to avoid error mentioned in #7

[codecov-commenter]

Codecov Report

Merging #8 into master will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master       #8   +/-   ##
=======================================
  Coverage   58.40%   58.40%           
=======================================
  Files           3        3           
  Lines         113      113           
=======================================
  Hits           66       66           
  Misses         47       47           

Impacted Files	Coverage Δ
src/core.jl	94.20% <100.00%> (ø)

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[jw3126]

Thanks! Can you add some unit tests? Feel free to add an Autodiff package as a test only dependency.

[jw3126]

(If you are not sure how to do that, just ping me)

[efmanu]

I am not sure how to do that...sorry

[jw3126]

Alright, I am happy to walk you through this. Can you provide a code snippet that exhibits the bug? Something like:

using ReverseDiff
using VoxelRayTracers

# some code that involes ray tracing and autodiff that crashes without this PR.

[efmanu]

I will try to make one