Swift Modulate Function

.swift

public extension FloatingPoint {
    typealias ModulationRange = (lowerBound: Self, upperBound: Self)
    
    /// Translates the given floating point between two ranges.
    /// Limit defaults to true. If limit is set to false, the value returned can be outside of the "to" range.
    ///
    /// Using the Modulate function
    /// ----------------------------------------------------------
    /// Say you'd like to transform a view's scale from `1.0` to `0.45` depending on some other factor, like scroll amount.
    /// The `from` could be `0...120` and the `to` would be`1.0...0.45`, which would mean at `0` content offset, the transform would be `1.0`
    /// and at `120` the transform would be `0.45`. The modulate function will interpolate the values in between.
    ///
    ///     let offset: CGFloat = 60
    ///     offset.modulate(from: (0, 120), to: (1.0, 0.45))
    ///     // returns 0.825
    ///
    /// - Parameter limit: Whether to clamp the return value to the `to` range.
    /// - Returns: A new scalar interpolated from the ranges.
    func modulate(from: ModulationRange, to: ModulationRange, limit: Bool = true) -> Self {
        let result = to.lowerBound + ((self - from.lowerBound) / (from.upperBound - from.lowerBound)) * (to.upperBound - to.lowerBound)
        if limit {
            if to.lowerBound < to.upperBound {
                if result < to.lowerBound { return to.lowerBound }
                if result > to.upperBound { return to.upperBound }
            } else {
                if result > to.lowerBound { return to.lowerBound }
                if result < to.upperBound { return to.upperBound }
            }
        }
        return result
    }
}