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//! # Angles Done With Integers //! //! ``` //! use integer_angles::Angle; //! //! assert_eq!(Angle::pi_2().cos::<f64>(), 0.0f64); //! ``` //! //! Here we go, down the rabbit hole of floating-point instability and all sorts of crazy problems //! that come with representing angles within computers. The goal of this library is to solve the //! following problems: //! //! * If you have multiple angles, and you add them together, the result you get should be exactly //! correct. //! * If you add multiple angles together and end up with a full circle, that should be exactly a //! full circle. //! * If you do trigonometry of some multiple of `pi` radians, you should end up with the exact //! answer. //! * Keep track of the difference between a `0` radian angle, and a `2 pi` radians angle. //! * Keep track of if the angle is going clockwise or counter-clockwise starting at the positive x //! axis. //! * Do not allow the user to represent an angle outside the range [`-2 pi` to `2 pi`] //! //! The way this library does it's magic is the following: //! //! * Stores the angle in units of `[0..2**64)` where each unit is `1/(2**64)`th of a circle. //! * This means that adding and subtracting angles (with wrapping) will always be correct, and //! always within the specified range. (No more range reduction!) //! * This also means that you can (inside the library) *cast* an angle from `u64` to `i64` and //! end up with the same angle. //! * Set a flag for a full circle, and allow units to be `0` for a `0` degree angle. //! * This also means, for example, `pi` radians is exactly equal to `1<<63` units in this library. //! * Keep track of the clockwise/counterclockwise-ness of the angle using a separate flag. //! * Solves the Chebyshev to compute the sin/cos/tan using the new units (with more precision //! than the standard library). //! * Uses a binary search (at the moment) to compute asin/acos/atan/atan2. //! //! Caveats: //! * This library is slower than using an f64 (about 10 times slower to compute `cos`. You've //! gotta wait a whole 80 ns to get the result!). //! * ... Probably other things. mod angle; #[cfg(test)] mod tests; #[cfg(test)] #[macro_use(quickcheck)] extern crate quickcheck_macros; pub use angle::Angle;