Written by Asteroth, derived from our ai code. I added a couple safety checks and changed the type to void to match our library.
Co-Authored-By: Asteroth <[email protected]>
Floating-point comparisons are tricky beasts. See this article for a good summary of the issues involved:
https://randomascii.wordpress.com/2012/02/25/comparing-floating-point-numbers-2012-edition/
This PR improves support somewhat, although there are obviously situations in the code (such as comparisons to 0) that should still be addressed. This PR makes the following improvements:
1) Tightens the threshold on `IS_VEC_NULL` and `IS_VEC_NULL_SQ_SAFE` from 1e-16 and 1e-36 to FLT_EPSILON
2) Tightens the threshold for parsing `turn_time` in POFs
3) Restores the previous implementation of `fl_equal`
4) Adds a dedicated `IS_MOI_VEC_NULL` for moment of inertia values
5) Improves documentation
Follow-up to #4535 and #4443.
In #4443, `fl_near_zero` was set to use default epsilon values in the `IS_VEC_NULL` check. In this comparison, epsilon is the wrong threshold because it used to have a much smaller threshold. The fix restores the previous definitions of `IS_VEC_NULL` and `IS_VEC_NULL_SQ_SAFE` by exposing the epsilon value as an optional parameter (similar to how `IS_NEAR_ZERO` used to work. This PR also restores `IS_VEC_NULL_SQ_SAFE` where it was replaced by `IS_VEC_NULL.`
* more cleanup in preparation for model translation
1) Clean up stepped rotation, fixing some logic, adding safeguards for invalid values, and allowing rotations to go in the opposite direction
2) Add more specific SEXP error checking for AWACS and rotating subsystems
3) Assorted refactoring and polishing
* address feedback, plus a bit of extra cleanup
* Change animation turret canonicalization to now correctly calculate the closest natual turret positon
* Add angle error to vm function for convenience
* Div by Zero safety for non IEEE compliant systems
* Incorporate style changes
Goober5000