Improvements for more straightforward and faster code

[mhliu0001]

These are some minor improvements that should not alter the behavior of fuse.

[coveralls]

Pull Request Test Coverage Report for Build 7883397465

Details

• 0 of 13 (100.0%) changed or added relevant lines in 5 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.01%) to 66.349%

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Totals
Change from base Build 7845769381:	-0.01%
Covered Lines:	1603
Relevant Lines:	2416

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💛 - Coveralls

[HenningSE]

Thanks for the PR @mhliu0001. Most of the changes look good! I would just remove the comments for the S1 photon hits, or what was your plan there?

[HenningSE]

Looking good! Thanks!

[ramirezdiego]

Thanks!

[dachengx]

I do not know if someone checked whether the result changed. If I change the version number back, and compare the old and new results. They are the same. So I think we are fine. Thumb to @mhliu0001 .