lottery-wheel

A library helps you performing a wheel for lottery game. Using anime.js underlying.

demo

Usage

npm install lottery-wheel

Or download the latest release.

Then link lottery-wheel.min.js or lottery-wheel.js in your HTML.

<script src="/path/to/lottery-wheel.min.js"></script>

ESM is supported as well.

import Wheel from 'lottery-wheel'

Suppose you have an element whose id is 'wheel' in your html file.

<svg id="wheel"></svg>

Then you can do the following to create a wheel:

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: [{
    text: 'apple',
    chance: 20
  }, {
    text: 'banana'
  }, {
    text: 'orange'
  }, {
    text: 'peach'
  }],
  onSuccess(data) {
    console.log(data.text);
  }
});

API

Methods

constructor(option)

More for option, see below.

draw()

To manually render the wheel when the draw property is set to false.

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: ['Beijing', 'London', 'New York', 'Tokyo'],
  draw: false
});
setTimeout(() => {
  wheel.draw();
}, 2000);

Options

Property	Description	Type	Default
el	The element where the wheel mounted. Details.	HTMLElement	-
data	An array of prizes. Details.	Array	-
pos	The top-left corner of the wheel related to its parent element (the el element).	Array	[0, 0]
radius	The radius of the wheel in px.	Number	100
buttonText	The text on the button.	String	'Draw'
fontSize	The size of text for prizes.	Number	(auto generate)
buttonWidth	The width of the button in px.	Number	50
buttonFontSize	The size of text on the button.	Number	(auto generate)
textRotate	If the text on each prize rotate 90 degrees.	Boolean	false
limit	The maxium times the wheel can be run.	Number	0 (unlimited)
duration	How long will the animation last in millseconds.	Number	5000
turn	The minimum amount of circles the wheel will turn during the animation.	Number	4
draw	If true, the wheel will be rendered immediately the instance created. Otherwise, you should call draw to manually render it.	Boolean	true
clockwise	If true, the rotation movement will be clockwise. Otherwise, it will be counter-clockwise.	Boolean	true
theme	The color preset to be used. Details.	String	'default'
image	Allow you to render the wheel using image resources. See image.	Object	-
color	An object used to override the color in the current theme. See themes	Object	-
onSuccess	The callback function called when a prize is drawn successfully. Details.	Function	-
onFail	The callback function called when trying to draw prize while has already drawn limit times. Details.	Function	-
onButtonHover	The function called when the mouse moves over the button. Details	Function	-

el

The el property defines the element where to render the wheel. You should pass a DOM Element to it:

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: []
});

data

The data property use an array to define the things relating to the lottery game itself. The length of the array must between 3 and 12.

The simplest way is to put the name of each prize in an array:

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: ['Beijing', 'London', 'New York', 'Tokyo']
});

It will generate the following wheel with default options. Every prizes take the same chance to be drawn, as the program will create four 'prize' objects with their text property set to the string in data array and chance property to 1 automatically.

You can also custom each prize by making it an object. The properties for the 'prize' object are listed here.

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: [{
    text: 'Beijing',
    chance: 5
  }, {
    text: 'London',
    chance: 4
  }, 'New York', 'Tokyo']
});

onSuccess

The callback function called when a prize is drawn successfully.

Parameter	Description	Type
data	The drawn 'prize' object.	Object

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: ['prize A', 'prize B', 'prize C', 'prize D'],
  onSuccess(data) {
    alert(`Congratulations! You picked up ${data.text}`);
  }
});

onFail

The callback function called when trying to draw prize while has already drawn the maximum times (defined in limit). Notice that by the default options, one can draw unlimited times.

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: ['prize A', 'prize B', 'prize C', 'prize D'],
  limit: 1,
  onFail() {
    alert('You have no more chance to draw');
  }
});

In this case, if one has already drawn a prize, the next time he clicks the button the alert dialog will be shown.

onButtonHover

Called when the mouse is moving over the button.

Parameter	Description	Type
anime	Refer to animejs. See the doc for usage.
button	Refer to the SVGImageElement where the button lies.	SVGImageElement

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: ['prize A', 'prize B', 'prize C', 'prize D'],
  onButtonHover(anime, button) {
    anime({
      targets: button.node,
      scale: 1.2,
      duration: 500
    });
  }
});

Prize Object

Property	Description	Type	Default
text	The name for the prize	String	''
chance	The probability the prize to be drawn. The higher the value, the more chances the prize to be picked up. The probability is actually calculated by the formula probability = 1 * chance / (sum of every prize's chance)	Number	1
color	The background color for the prize (will override color.prize of Wheel).	String	-
fontColor	The color of the text (will override color.fontColor of Wheel).	String	-
fontSize	The size of the text (will override fontSize of Wheel).	Number	-

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: [{
    text: 'Beijing',
    color: 'silver',
    fontSize: 24
  }, {
    text: 'London',
    fontColor: '#008000'
  }, 'New York', 'Tokyo']
});

The above code will result the following wheel:

Themes

A theme is an object where stores the colors used in the wheel. It has following properties:

• border: background color for the wheel's border.
• prize: background color for the prize part.
• button: background color for the button.
• line: color for the line between prize parts.
• prizeFont: color for prize text.
• buttonFont: color for button text.

There are three themes preseted:

• default

default: {
    border: 'red',
    prize: 'gold',
    button: 'darkorange',
    line: 'red',
    prizeFont: 'red',
    buttonFont: 'white'
}

• light

light: {
    border: 'orange',
    prize: 'lightyellow',
    button: 'tomato',
    line: 'orange',
    prizeFont: 'orange',
    buttonFont: 'white'
}

• dark

dark: {
    border: 'silver',
    prize: 'dimgray',
    button: 'darkslategray',
    line: 'silver',
    prizeFont: 'silver',
    buttonFont: 'lightyellow'
}

You can also change the color by setting color property.

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: ['Beijing', 'London', 'New York', 'Tokyo'],
  theme: 'dark',
  color: {
    button: '#fef5e7',
    buttonFont: '#34495e'
  }
});

Image

The image property lets you render the wheel using the existing resources by setting an object. It will make an image SVG element and it supports jpeg, png and svg formats.

Property	Description	Type
turntable	The image for the turntable.	String
button	The image for the button. It's width is controled by buttonWidth property and the aspect ratio will be preserved. Centered in the turntable by default.	String
offset	The y-axis offsets for the button. If negative, the button moves up.	Number

Here's an example of how it looks like when using the images in /doc/images folder in this repo.

const wheel = new Wheel({
  el: document.getElementById('wheel'),
  data: ['Prize A', 'Prize B', 'Prize C', 'Prize D', 'Prize E', 'Prize F'],
  image: {
    turntable: 'turntable.png',
    button: 'button.png',
    offset: -10
  },
});