Change the casts used in the convenience #defines in floating.h. Since these #defines are used pretty widely, this should reduce the count of C-style casts in the codebase by quite a bit.
Also change the casts in floating.cpp while we're at it, and remove some obsolete or unused code.
This adds a new field to particle effects so that particle rotation can be configured on a per-type basis, not just on a blanket basis. Implements #5941.
The ai-fly-to-ship goal was added early in FSO's development but never worked right. Until recently it could crash; and even aside from the crash the AI would try to reach the target's exact position, causing repeated collisions. This folds ai-fly-to-ship into ai-stay-near-ship, since the behaviors are conceptually the same except for fly-to being satisfied as soon as the target is in range.
This also adds a new "escort" mode usable by both behaviors. The default Volition behavior is to swoop toward the target in a long, graceful arc; the new mode generates a goal point and flies directly to that point. These can be toggled via an optional sexp parameter.
There is also some minor cleanup and a new vec3d operator for convenience.
Needed for Scroll; depends on #5667.
See title. There were some cascade effects, but the changes are mostly contained to the model code. The calls to `gr_render_model` and `g3_render_primitives` use `const_cast` because constifying that API would require a whole other PR.
The `SCP_string_lcase_equal_to()()` and `SCP_string_lcase_less_than()()` functors are rather unwieldy to use in non-functor situations, so this adds conventional function equivalents.
Adds gravity! Applies on a per-mission basis, and weapons, ships, debris, and asteroids now have a configurable "gravity const" which multiplies the effect of gravity on them, by default everything except debris is 0 (meaning no effect even when the mission has gravity). AI and the lead indicator will also lead for ballistic trajectories as well, given a gravity-affected weapon. No FRED support or gravity direction control yet, to come in later PRs.
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