Add straight guide component (numpy implementation)

ckendrick commented 2 years ago

This adds the remainder of the straight guide implementation which is based off of #19 (should be merged before this PR).

This is still a WIP, some remaining tasks to do:

[x] Add tests for neutrons reflecting off the guide (miss, hit one side, hit both, straight through guide, etc)
[ ] Vectorize the velocity reflection update
[ ] Adjust reflectivity calculation to mask out neutrons that are invalid or already have hit the exit to reduce redundant calculations
[x] Investigate/fix the test_guide_cpu.py test case for differences between the MCViNE guide.
[x] Refactor guide testing code to test_guide_cpu.py to separate implementation from tests.

~~Some of this work is being done in #20 which needs to be merged into this branch.~~

The leftover tasks above will be handled in a separate PR.

yxqd commented 2 years ago

@ckendrick @mtbc I just merged #19

ckendrick commented 2 years ago

@yxqd Thanks! I will rebase this branch from main later this afternoon.

mcvine / acc