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$.linearGradient( attributes );

Returns: jSignage Object


Creates a linear gradient that maps colors and opacity values at specific offsets along a gradient vector.

The linear gradient is not directly rendered, instead it needs to be referenced (using its id or calling the .ref() function) by attributes expecting a color (like 'fill', 'stroke', 'backColor', 'frameColor' etc.). The gradient must exist or be added into the DOM in order to be referenced (it does not matter where the gradient is added though).

See Linear gradients in the SVG specification for reference.


  • attributes
    Type: Plain Object.
    Contains the linear gradient attributes.


The following attributes can be specified:

  • x1, y1, x2, y2
    Type: Number. Default: 0.
    x and y coordinates of the starting point, respectively the ending point, of the gradient vector.
  • gradientUnits
    Type: String. Default: 'userSpaceOnUse'.
    Defines the coordinate system for attributes 'x1', 'y1', 'x2', 'y2' to be used when rendering the gradient. Can be 'userSpaceOnUse' or 'objectBoundingBox'. Note that when using 'objectBoundingBox', the x and y attributes need to take values between 0 and 1 for the gradient to be visible.
  • stops
    Type: Array.<Plain Object>.
    List of the gradient stops. Each stop is an object with the following properties:
    • offset
      Type: Number. Default: 0.
      Relative position of the stop along the gradient vector. It takes values from 0 to 1, where offset 0 corresponds to the starting point of the vector (specified by x1 and y1 attributes) and offset 1 corresponds to the ending point of the vector (specified by x2 and y2 attributes).
    • color
      Type: Color. Default: 'black'.
      The color to be used at the gradient stop.
    • opacity
      Type: Number. Default: 1.
      The opacity to be used at the gradient stop.
Note Notes:
  • At least two offsets should be specified to produce a gradient. If no stops are specified, the gradient will have the same effect as color: 'none' and if only one stop is specified, the result is a solid color. Each stop offset must be greater than or equal to the previous stop offset.
  • An offset can be repeated to produce a discontinuity in the gradient, i.e. the first stop will terminate a linear interpolation and the second stop will start a new one, allowing for an immediate jump in color or opacity. See example #2.
  • The color and opacity of each stop can be animated using animateColor and respectively animateOpacity, by specifying an index into the stop array as the first argument to these functions. See example #3.


Horizontal gradient from blue to red

Simple linear gradient
var grad = $.linearGradient({
   x1: 320,
   y1: 0,
   x2: 960,
   y2: 0,
   stops: [
     { offset: 0, color: 'blue' },
     { offset: 1, color: 'red' }
$.rect({ x: 320, y: 180, width: 640, height: 360, fill: grad.ref() }).addTo('svg');

Vertical gradient with discontinuity

Linear gradient with discontinuity
var grad = $.linearGradient({
   x1: 0,
   y1: 100,
   x2: 0,
   y2: 300,
   stops: [
     { offset:   0, color: '#c0c0ff' },
     { offset: 0.5, color: '#8080ff' },
     { offset: 0.5, color: '#6060ff' },
     { offset:   1, color: '#6060ff' },
$.rect({ x: 100, y:100, width: 600, height: 200, fill: grad.ref() }).addTo('svg');

Horizontal gradient animated from red to green

Animated linear gradient at t=1s.
Animated linear gradient at t=3s.
var grad = $.linearGradient({
   x1: 320,
   y1: 0,
   x2: 960,
   y2: 0,
   stops: [
     { offset: 0, color: 'white' },
     { offset: 1, color: 'red' }
$.rect({ x: 320, y: 180, width: 640, height: 360, fill: grad.ref() }).addTo('svg');
grad.animateColor( 1, {
   begin: 1,
   from: 'red',
   to: 'green',
   dur: 2,
   fill: 'freeze',   
  • Note that in the color animation, 1 is used to reference the second stop of the gradient (stops are numbered from 0).
This page was last modified on 20 February 2019, at 17:15.