SVG.js

Animating

Animating elements is very much the same as manipulating elements using the attr() method. The only difference is you have to include the animate() method.

Method chain

Note that the animate() method will not return the targeted element but an instance of SVG.FX which will take the following methods:

Of course attr():

rect.animate().attr({ fill: '#f03' })

The x(), y() and move() methods:

rect.animate().move(100, 100)

And the cx(), cy() and center() methods:

rect.animate().center(200, 200)

Or transformation methods:

rect.animate().rotate(45).skew(25, 0)

You can also animate non-numeric unit values using the attr() method:

rect.attr('x', '10%').animate().attr('x', '50%')

Easing

All available ease types are:

  • <>: ease in and out
  • >: ease out
  • <: ease in
  • -: linear
  • =: external control
  • a function

For the latter, here is an example of the default <> function:

function(pos) { return (-Math.cos(pos * Math.PI) / 2) + 0.5 }

For more easing equations, have a look at the svg.easing.js plugin.

animate()

returns SVG.FX

rect.animate().move(150, 150)

The animate() method will take three arguments. The first is duration, the second ease and the third delay:

rect.animate(2000, '>', 1000).attr({ fill: '#f03' })

Alternatively you can pass an object as the first argument:

rect.animate({ ease: '<', delay: '1.5s' }).attr({ fill: '#f03' })

By default duration will be set to 1000, ease will be set to <>.

You can chain multiple animations together by calling animate again:

rect.animate({ ease: '<', delay: '1.5s' }).attr({ fill: '#f03' }).animate().dmove(50,50)

situation

returns object

The current situation of an animation is stored in the situation object:

rect.animate(3000).move(100, 100)
rect.fx.situation //-> everything is in here

Available values are:

  • start (start time as a number in milliseconds)
  • play (animation playing or not; true or false)
  • pause (time when the animation was last paused)
  • duration (the chosen duration of the animation)
  • ease (the chosen easing calculation)
  • finish (start + duration)
  • loop (the current loop; counting down if a number; true, false or a number)
  • loops (if a number, the total number loops; true, false or a number)
  • reverse (whether or not the animation should run backwards)
  • reversing (true if the loop is currently reversing, otherwise false)

target()

returns SVG.Element

The target method returns the element the animation is applied to:

rect.fx.target() // returns rect


Controlling

finish()

returns itself

This method finishes the whole animation chain. All values are set to their corresponding end values and every situation gets fullfilled

rect.animate().move(200, 200).animate().dmove(50,50).size(300,400)

rect.finish() // rect at 250,250 with size 300,400

pause()

returns itself

Pausing an animations is fairly straightforward:

rect.animate().move(200, 200)

rect.mouseover(function() { this.pause() })

play()

returns itself

Will start playing a paused animation:

rect.animate().move(200, 200)

rect.mouseover(function() { this.pause() })
rect.mouseout(function() { this.play() })

reverse()

returns itself

Toggles the direction of the animation or sets it to a specific direction:

// will run from 100,100 to rects initial position
rect.animate(3000).move(100, 100).reverse()

// sets direction to backwards
rect.animate(3000).move(100, 100).reverse(true)

// sets direction to forwards (same as not calling reverse ever)
rect.animate(3000).move(100, 100).reverse(false)

stop()

returns itself

If you just want to stop an animation you can call the stop() method which has two optional arguments:

  • jumpToEnd: Sets the values to the end of the animation
  • clearQueue: Remove all items from queue
rect.animate().move(200, 200)

rect.stop()
// or e.g.
rect.stop(true)

Stopping an animation is irreversible.


Timing

at()

returns itself

Say you want to control the position of an animation with an external event, then the at() method will prove very useful:

var animation = draw.rect(100, 100).move(50, 50).animate('=').move(200, 200)

document.onmousemove = function(event) {
  animation.at(event.clientX / 1000)
}

The value passed as the first argument of at() should be a number between 0 and 1, 0 being the beginning of the animation and 1 being the end. Note that any values below 0 and above 1 will be normalized.

Also note that the value is eased after calling the function. Therefore the position specifies a position in time not in space.

delay()

returns itself

Alternatively, you can call delay() which will set a delay in ms before the next animation in the queue is run

rect.animate({ ease: '<', delay: '1.5s' }).attr({ fill: '#f03' }).delay(500).animate().dmove(50,50)

loop()

returns SVG.FX

By default the loop() method creates and eternal loop:

rect.animate(3000).move(100, 100).loop()

But the loop can also be a predefined number of times:

rect.animate(3000).move(100, 100).loop(3)

Loops go from beginning to end and start over again (0->1.0->1.0->1.).

There is also a reverse flag that should be passed as the second argument:

rect.animate(3000).move(100, 100).loop(3, true)

Loops will then be completely reversed before starting over (0->1->0->1->0->1.).

once()

returns itself

Finally, you can perform an action at a specific position only once. Just pass the position and the function which should be executed to the once method. You can also decide whether the position which is passed should be handled as position in time (not eased) or position in space (easing applied):

// the 0.5 is handled as uneased value (you can omit the false)
rect.animate(3000).move(100, 100).once(0.5, function(pos, eased) {
  // do something
}, false)
// the 0.5 is handled as eased value
rect.animate(3000).move(100, 100).once(0.5, function(pos, eased) {
  // do something
}, true)

The callback function gets the current position uneased and eased.

queue()

returns itself

If you want to call a custom funtion between two chained animations, you simply can queue them up:

rect.animate({ ease: '<', delay: '1.5s' }).attr({ fill: '#f03' }).queue(function(){

    this.target().fill('#000')
    this.dequeue() // dont forget to call dequeue when the queue should continue running

}).animate().dmove(50,50)


Callbacks

after / afterAll()

returns itself

Furthermore, you can add callback methods using after()/afterAll():

rect.animate(3000).move(100, 100).after(function(situation) {
  this.animate().attr({ fill: '#f06' })
})

// or
rect.animate(3000).move(100, 100).afterAll(function() {
  this.animate().attr({ fill: '#f06' })
})

The function gets the situation which was finished as first parameter. This doesn't apply to afterAll where no parameter is passed
Note that the after()/afterAll() method will never be called if the animation is looping eternally.
You can call after()/afterAll() multiple times to add more functions which should be executed.

during / duringAll()

returns itself

If you want to perform your own actions during one/all animation you can use the during()/duringAll() method:

var position
  , from = 100
  , to   = 300

rect.animate(3000).move(100, 100).during(function(pos, morph, eased, situation) {
  position = from + (to - from) * pos
})

// or
rect.animate(3000).move(100, 100).duringAll(function(pos, morph, eased, situation) {
  position = from + (to - from) * pos
})

Note that pos is 0 in the beginning of the animation and 1 at the end of the animation.

To make things easier a morphing function is passed as the second argument. This function accepts a from and to value as the first and second argument and they can be a number, unit or hex color:

var ellipse = draw.ellipse(100, 100).attr('cx', '20%').fill('#333')

rect.animate(3000).move(100, 100).during(function(pos, morph, eased, situation) {
  // numeric values
  ellipse.size(morph(100, 200), morph(100, 50))

  // unit strings
  ellipse.attr('cx', morph('20%', '80%'))

  // hex color strings
  ellipse.fill(morph('#333', '#ff0066'))
})

The eased parameter contains the position after the easing function was applied.
The last parameter holds the current situation related to the current during call.
You can call during()/duringAll() multiple times to add more functions which should be executed.

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