import {cubehelix, defaultHelixConfig} from 'cubehelix';

/*
 * Generate a mapping function with the default
 * helix configuration. I.e. default start, rotations,
 * hue and gamma are assumed
 */
var mappingFunction = cubehelix();

/*
 * Get the RGB values (scaled in the [0, 1] range) for a
 * value with intensity 0.5 (0 being the lowest, 1 the highest)
 */        
var rgb = mappingFunction(0.5);

/*
 * Generate a different mapping function by providing
 * a full helix configuration different than the default
 */
mappingFunction = cubehelix({start: 0.75, r:-0.5, hue:0.8, gamma:2.0});

/*
 * Alternatively, you may choose to provide only some of the configuration
 * parameters while keeping default values for the rest
 */
mappingFunction = cubehelix({r:-0.5, gamma: 2.0});

/*
 * NB: for many non-default helix configuration values the mapping
 * function may generate RGB components outside of the [0, 1] range
 * The client programmer is responsible for clipping to [0, 1].
 * The more clipping occurs, the more the monotonicity of perceived luminosity 
 * may suffer.
 */

/*
 * Print the default helix configuration
 */
console.log(JSON.stringify(defaultHelixConfig));