`Color::FromHSV` didn't match the Java `Color.fromHSV` in some saturated
edge cases, introducing an off-by-one error when the HSV color should
correspond complete saturation of one or two of the primary colors.
Example:
- Java: `Color.fromHSV(0, 255, 255) -> (255, 0, 0)`
- C++: `Color::FromHSV(0, 255, 255) -> (255, 1, 1)`
This also means the following methods are also transitively affected:
- `AddressableLED::LEDData::SetHSV`
- `LEDPattern::Rainbow`
This off-by-one error is introduced by a rounding error from the chroma
calculation, which was dividing by 256 rather than the appropriate
maximum value of 255 like in Java:
7ca35e5678/wpilibj/src/main/java/edu/wpi/first/wpilibj/util/Color.java (L176-L177)
Also port appropriate tests from Java to C++ to catch this bug.
I found this bug when I tried to port `AddressableLEDBuffer` to RobotPy.
Codex found the root cause :)
Since sched_setscheduler() requires non-RT priorities to be 0, we can
use that as a sentinel value for disabling RT and condense the Java API
to just two functions with fewer parameters. The thread priority setter
is deprecated since only experts should use it.
The HAL Notifier thread priority setter was replaced with setting the
priority in the thread itself.
The C++ Notifier non-RT and RT constructors were deduplicated.
The real-time scheduler was changed from SCHED_FIFO to SCHED_RR, which
is SCHED_FIFO with threads allowed to run for a maximum time quantum
before yielding (100 ms by default).
#7695, #7696, #7697, #7701, #7724, #7753, #7861 removed various features
from the HAL, but forgot to clean up the handles, the WS API, or both.
Additionally, since AnalogInput is the only remaining analog I/O,
AnalogJNI was renamed to the more specific AnalogInputJNI.
The epoch() function, zero() function, and min_time member are all not
part of the std::chrono clock interface.
The default constructor of time_point is
[documented](https://en.cppreference.com/w/cpp/chrono/time_point/time_point.html)
to initialize to the clock's epoch.
- Remove status return from HAL level (clock getting should never fail)
- Remove 32-bit timestamp expand function
- Make monotonic_clock.hpp (formerly fpga_clock.hpp) header-only and
move to root hal include directory
Makes Java `Alert.Level.ERROR`, `Alert.Level.WARNING`, and
`Alert.Level.INFO` proper aliases (instead of separate enum constants
with the same value).
Cleans up Python tests.
Makes the Alert tests more consistent between languages.
I left "free speed" alone since that's the technical term for it. In
general, velocity is a vector quantity, and speed is a magnitude (i.e.,
a strictly positive value).
This PR also replaces the speed verbiage in MotorController with duty
cycle.
Fixes#8423.
