21 releases (10 stable)
1.3.1 | Sep 19, 2024 |
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1.2.3 | Jul 24, 2024 |
0.10.0 | Apr 18, 2024 |
0.9.0 | Mar 27, 2024 |
0.2.0 | Nov 12, 2023 |
#204 in Rust patterns
880 downloads per month
Used in 8 crates
(5 directly)
48KB
1.5K
SLoC
iFloat
This fixed float math library provides an efficient and deterministic solution for arithmetic and geometric operations.
Features
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Fixed-point arithmetic using FixNumber for deterministic calculations
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2D fixed-point vector operations with FixVec
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Trigonometric functions using fixed-point angles
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Angle conversion and manipulation utilities in FixAngle
Installation
use i_float::fix_float::FixFloat;
use i_float::fix_vec::FixVec;
How It Works
The `FixFloat` struct uses fixed-point arithmetic to perform calculations with a high degree of precision and determinism. It supports numbers in the range 2^21 - 1 to -2^21 + 1 with a precision of 1/1024, and is most suitable for the range 1,000,000 to -1,000,000 with a precision of 0.01.
Fixed-point numbers are represented using a fixed number of bits for the fractional part. In this implementation, the number of bits representing the fractional part of the fixed-point number is 10, which allows for a precision of 1/1024 or approximately 0.001.
Here are some examples of fixed-point number representation:
- 1 / 1024 ≈ 0.001 (represented as 1)
- 256 / 1024 = 0.25 (represented as 256)
- 1024 / 1024 = 1 (represented as 1024)
- (1024 + 512) / 1024 = 1.5 (represented as 1536)
- (2048 + 256) / 1024 = 2.25 (represented as 2304)
By using the `FixFloat` struct, you can perform arithmetic operations using i64 values while maintaining the precision of floating-point numbers, ensuring deterministic behavior across different platforms and devices.
Usage
FixFloat
The `FixFloat` struct represents a fixed-point number using a `i64` as the underlying storage, allowing deterministic arithmetic operations. Use `FixFloat` for calculations instead of `i32` or `i64` when deterministic behavior is required. `FixFloat` provides a way to perform arithmetic operations with `i64` values while maintaining the precision of floating-point numbers.
let a = FixFloat::new_number(1);
let b = FixFloat::new_number(2);
let c = a + b;
FixVec
The `FixVec` struct represents a 2D fixed-point vector, providing various utility methods and operators for vector operations. Use `FixVec` for 2D geometric calculations when deterministic behavior is required.
let a = FixVec::new_number(1, 1);
let b = FixVec::new_number(1, -1);
let c = a + b;
FixAngle
The `FixAngle` class provides various utility methods for working with fixed-point angles, including trigonometric functions and angle conversion.
let fix_angle = FixAngle::new_from_radians_f64(angle);
let fix_sin = fix_angle.sin();
let i64_sin = fix_sin.double();
License
Dependencies
~0.4–1MB
~22K SLoC