decrement

Decrement random value in array. Image below demonstrates random decrements in rgb(255,255,255) structure.

(See sample output test.html for full dataset)

// install decrement
npm i -S decrement

// load
const decrement = require("decrement");

// cap at range of 0..255
const control = decrement({min:0, max:255});

// helper rate change
const rnd = function (min, max) {
  min = Math.ceil(min);
  max = Math.floor(max);
  return Math.floor(Math.random() * (max - min + 1)) + min;
}

// insert objects
control.insert ( { kind: 'red'   , value: 255 } ) ;
control.insert ( { kind: 'green' , value: 255 } ) ;
control.insert ( { kind: 'blue'  , value: 255 } ) ;

// while above 0
while( control.total() > 0){

  // find blue and change by a random value in range -2..1
  control.change({kind: 'blue'},  rnd(-2,1));

  // find green and change by a random value in range -2..1
  control.change({kind: 'green'}, rnd(-2,1));

  // find red and change by a random value in range -2..1
  control.change({kind: 'red'},   rnd(-2,1));

  // print some html
  console.log( '<div style="background: rgb(' + control.data().map(i=>i.value).join() + '); height:1px;"></div>' );
}