Normalized Range Mapper

A Rust helper than maps ranges of values to and from the normalized range [0.0, 1.0] using various gradients, useful for DSP applications.

(currently in beta)

Gradient Types

• LinearMap - Linear mapping. This can use either generic or decibel units.
• PowerMap - Exponential mapping where the normalized value is raised to the supplied exponent. This can use either generic or decibel units.
• Log2Map - Logarithmic mapping using log2. This is useful for frequency (Hz) values.
• Discrete - Discrete isize integer mapping. A supplied enum may also be used as well as long as it implements From<isize> + Into<isize> + Copy + Clone. This mapper has methods for converting to and from either float values or isize/enum values.

Installation

Add normal_map as a dependency in your Cargo.toml:

normal_map = 0.2

Example

// Import normal mappers that use internal f32 values.
// (f64 is available as well)
use normal_map::f32::*;

// Linear mapper
let lin_map = LinearMap::new(-50.0, 50.0, Unit::Generic);

assert!((lin_map.normalize(25.0) - 0.75).abs() <= 0.0001);
assert!((lin_map.denormalize(0.25) - (-25.0)).abs() <= 0.0001);

// Efficiently map an array/slice of values.
let in_normals = [0.0f32, 1.0, 0.25, -0.25];
let mut out_values = [0.0f32; 4];
lin_map.denormalize_array(&in_normals, &mut out_values);

// Generic type for any mapper
let normal_map = NormalMap::discrete::<isize>(-5, 5);

assert!((normal_map.normalize(3 as f32) - 0.8).abs() <= 0.0001);