This is an old revision of the document!

Design Parameters

A design can have parameters by declaring a special function; getParameterDefinitions().

In applications and browsers, these parameters are presented to users, allowing users to interactively change designs.


This function must return an array of parameter definitions, as show below.

function getParameterDefinitions() {
    return [
        { name: 'length', type: 'int', initial: 150, caption: 'Length?' }, 
        { name: 'width', type: 'int', initial: 100, caption: 'Width?' },

The parameters are evaluated and values are passed into the main function. Be sure to declare the main function properly.

function main(params) {
  var l = params.length;
  var w = params.width;

Parameter Types

The parameters are defined as input fields on a single HTML5 form, i.e. the list of parameters. For more information on HTML5 input fields, see some examples at W3 Schools.

Note: Browsers are NOT the same and will treat unsupported parameter types as TEXT.

Type Example Returned Value
checkbox {name: 'bigorsmall', type: 'checkbox', checked: true, caption: 'Big?'} if checked true, else false
checkbox {name: 'bigorsmall', type: 'checkbox', checked: true, initial: 20, caption: 'Big?'} if checked 20, else false
color { name: 'color', type: 'color', initial: '#FFB431', caption: 'Color?' } “#rrggbb”, use html2rgb() to convert
date {name: 'birthday', type: 'date', caption: 'Birthday?'} “YYYY-MM-DD”
email {name: 'address', type: 'email', caption: 'Email Address?'} string value
float {name: 'angle', type: 'number', initial: 2.5, step: 0.5, caption: 'Angle?'} float value
int {name: 'age', type: 'int', initial: 20, caption: 'Age?'} integer value
number {name: 'angle', type: 'number', initial: 2.5, step: 0.5, caption: 'Angle?'} float value
password {name: 'password', type: 'password', caption: 'Secret?'} string value
slider {name: 'count', type: 'slider', min: 2, max: 10, caption: 'How many?'} float value
text {name: 'name', type: 'text', caption: 'Name?'} string value
url {name: 'webpage', type: 'url', caption: 'Web page URL?'} string value
group { name: 'balloon', type: 'group', caption: 'Balloons' } none, only displayed

Note: The parameters accept additional restrictions and assistance. These include 'initial', 'max', 'maxLength', 'min', 'pattern', 'placeholder', 'size', and 'step'.