Panzoom is a small library (~3.7kb gzipped) to add panning and zooming functionality to an element. Rather than using absolute positioning or setting width and height, Panzoom uses CSS transforms to take advantage of hardware/GPU acceleration in the browser, which means the element can be anything: an image, a video, an iframe, a canvas, text, WHATEVER.
For common support questions, see the FAQ.
Here is a list of currently supported browsers.
iOS, Android, and Windows Mobile are supported.
Panzoom includes support for touch gestures and even supports pinch gestures for zooming. It is perfectly suited for both mobile and desktop browsers. It uses pointer events by default wherever supported.
Panzoom supports panning and zooming SVG elements directly.
In IE11, CSS animations/transitions do not work on SVG elements, at least for the transform style. They do work in other browsers.
One could implement transitions manually in IE11 using the setTransform option and integrating a tweening library for javascript animations (such as tween.js).
With npm:
$ npm install --save @panzoom/panzoomWith yarn:
$ yarn add @panzoom/panzoomPanzoom uses UMD and can be loaded a lot of ways.
With ES6 imports:
import Panzoom from '@panzoom/panzoom'With commonjs or browserify:
const Panzoom = require('@panzoom/panzoom')With an AMD loader in an anonymous module:
define(['@panzoom/panzoom'], function (Panzoom) {
const elem = document.getElementById('panzoom-element')
Panzoom(elem)
})With a script tag:
<script src="/js/panzoom.js"></script>With a script tag from a CDN:
<script src="https://unpkg.com/@panzoom/[email protected]/dist/panzoom.min.js"></script>const elem = document.getElementById('panzoom-element')
const panzoom = Panzoom(elem, {
maxScale: 5
})
panzoom.pan(10, 10)
panzoom.zoom(2, { animate: true })
// Panning and pinch zooming are bound automatically (unless disablePan is true).
// There are several available methods for zooming
// that can be bound on button clicks or mousewheel.
button.addEventListener('click', panzoom.zoomIn)
elem.parentElement.addEventListener('wheel', panzoom.zoomWithWheel)1. What is transform-origin and why is it added to the panzoom element?
- The
transform-originis the origin from which transforms are applied. Panzoom ensures the defaults are set to what it expects to calculate focal point zooming. - HTML elements default to '50% 50%'.
- SVG elements default to '0 0'.
2. I am using Panzoom with an <object> tag and it's not working. What's wrong?
Object elements can eat up events, making it so they never reach Panzoom. To fix this, disable pointer events (pointer-events: none) on the <object> tag and call Panzoom using a wrapper.
3. My links aren't working! How do I enable an anchor within a panzoom element?
Add class options.excludeClass (default is "panzoom-exclude") to whatever element you want to be clickable. Panzoom will check for this class before handling the event.
Alternatively, add a reference to the element to the exclude option, or call event.stopImmediatePropagation() in an event handler on the clickable element.
In some cases, setting one thing and then setting another synchronously will not work as intended.
For instance, the following usually works fine.
const panzoom = Panzoom(elem)
panzoom.zoom(2)
panzoom.pan(100, 100)However, you might find that the things start breaking when the contain option is set.
This is due to the fact that in order for Panzoom to retrieve proper dimensions, the scale needs to be painted.
If you find that things aren't looking quite right, try the following instead...
panzoom.zoom(2)
setTimeout(() => panzoom.pan(100, 100))4. I'm using Panzoom with SVG text elements and am seeing some weird text resizing. How do I fix this?
Add text-rendering="geometricPrecision" to your <text> elements.
<text text-rendering="geometricPrecision" x="40" y="120">Hello World</text>5. I'm using Panzoom on a canvas element that renders a PDF. How do I avoid the PDF getting blurry when scaled?
See this stackoverflow question
▸ Panzoom(elem, options?): [PanzoomObject](#PanzoomObject)
| Name | Type |
|---|---|
elem |
HTMLElement | SVGElement |
options? |
Omit<[PanzoomOptions](#PanzoomOptions), "force"> |
[PanzoomObject](#PanzoomObject)
Includes MiscOptions, PanOptions, and ZoomOptions
These options can be passed to Panzoom(), as well as any pan or zoom function. One exception is force, which can only be passed to methods like pan() or zoom(), but not Panzoom() or setOptions() as it should not be set globally.
• Optional animate: boolean (Default: false)
Whether to animate transitions
• Optional canvas: boolean (Default: false)
This option treats the Panzoom element's parent as a canvas. Effectively, Panzoom binds the down handler to the parent instead of the Panzoom element, so that pointer events anywhere on the "canvas" moves its children. See issue #472.
Note: setting this option to true also changes
where the cursor style is applied (i.e. the parent).
• Optional duration: number (Default: 200)
Duration of the transition (ms)
• Optional easing: string (Default: "ease-in-out")
CSS Easing used for transitions
• Optional exclude: Element[] (Default: [])
Add elements to this array that should be excluded from Panzoom handling. Ancestors of event targets are also checked. e.g. links and buttons that should not propagate the click event.
• Optional excludeClass: string (Default: "panzoom-exclude")
Add this class to any element within the Panzoom element that you want to exclude from Panzoom handling. That element's children will also be excluded. e.g. links and buttons that should not propagate the click event.
• Optional force: boolean
force should be used sparingly to temporarily
override and ignore options such as disablePan,
disableZoom, and panOnlyWhenZoomed.
This option cannot be passed to the
Panzoom constructor or setOptions (to avoid
setting this option globally).
// Overrides disablePan and panOnlyWhenZoomed
panzoom.pan(50, 100, { force: true })
// Overrides disableZoom
panzoom.zoom(1, { force: true })• Optional noBind: boolean
Skip binding the default Panzoom event listeners
• Optional origin: string
Change this at your own risk.
The transform-origin is the origin from which transforms are applied.
Default: '50% 50%' for HTML and '0 0' for SVG.
The defaults are set because changing the transform-origin on
SVG elements doesn't work in IE.
Changing this should work with many things, but it will break focal point zooming, which assumes the defaults are set to do the more complicated calculations.
And again, changing this for SVG in IE doesn't work at all.
• Optional overflow: string (Default: "hidden")
The overflow CSS value for the parent. Defaults to 'hidden'
• Optional setTransform: (elem: HTMLElement | SVGElement, __namedParameters: CurrentValues, _options?: PanzoomOptions) => void
Set the transform using the proper prefix
Override the transform setter. This is exposed mostly so the user could set other parts of a transform aside from scale and translate. Default is defined in src/css.ts.
// This example always sets a rotation
// when setting the scale and translation
const panzoom = Panzoom(elem, {
setTransform: (elem, { scale, x, y }) => {
panzoom.setStyle('transform', `rotate(0.5turn) scale(${scale}) translate(${x}px, ${y}px)`)
}
})| Name | Type |
|---|---|
elem |
HTMLElement | SVGElement |
__namedParameters |
CurrentValues |
_options? |
PanzoomOptions |
void
• Optional silent: boolean
Silence all events
• Optional startScale: number (Default: 1)
Scale used to set the beginning transform
• Optional startX: number (Default: 0)
X Value used to set the beginning transform
• Optional startY: number (Default: 0)
Y Value used to set the beginning transform
• Optional touchAction: string (Default: "none")
This value is used to set touch-action on both the Panzoom element and its parent. It is needed because that the native scroll on mobile interferes with panning and pinch zooming. Set this to empty string to re-enable scrolling on mobile, but note that both scrolling and panning cannot work at the same time.
▸ Optional handleStartEvent(event): void
On the first pointer event, when panning starts,
the default Panzoom behavior is to call
event.preventDefault() and event.stopPropagation()
on that event. The former is almost certainly a necessity;
the latter enables Panzoom elements within Panzoom elements.
But there are some cases where the default is not the desired behavior. Set this option to override that behavior.
// Only call preventDefault()
Panzoom(elem, {
handleStartEvent: (event) => {
event.preventDefault()
}
})
// Do nothing.
// This can change dragging behavior on mobile.
Panzoom(elem, {
handleStartEvent: () => {}
})| Name | Type |
|---|---|
event |
Event |
void
• Optional contain: "inside" | "outside"
Contain the panzoom element either inside or outside the parent. Inside: The panzoom element is smaller than its parent and cannot be panned to the outside. Outside: The panzoom element is larger than its parent and cannot be panned to the inside. In other words, no empty space around the element will be shown.
Note: the containment pan adjustment is not affected by the disablePan option.
• Optional cursor: string (Default: "move")
The cursor style to set on the panzoom element
• Optional disablePan: boolean (Default: false)
Disable panning functionality. Note: disablePan does not affect focal point zooming or the contain option. The element will still pan accordingly.
• Optional disableXAxis: boolean (Default: false)
Pan only on the Y axis
• Optional disableYAxis: boolean (Default: false)
Pan only on the X axis
• Optional panOnlyWhenZoomed: boolean (Default: false)
Disable panning while the scale is equal to the starting value
• Optional relative: boolean (Default: false)
When passing x and y values to .pan(), treat the values as relative to their current values
• Optional roundPixels: boolean
Round x and y values to whole numbers. This can help prevent images and text from looking blurry, but the higher the scale, the more it becomes necessary to use fractional pixels. Use your own judgment on how much to limit zooming in when using this option.
• Optional disableZoom: boolean (Default: false)
Disable zooming functionality
• Optional focal: Object
Zoom to the given point on the panzoom element. This point is expected to be relative to the panzoom element's dimensions and is unrelated to the parent dimensions.
| Name | Type |
|---|---|
x |
number |
y |
number |
• Optional maxScale: number (Default: 4)
The maximum scale when zooming
• Optional minScale: number (Default: 0.125)
The minimum scale when zooming
• Optional step: number (Default: 0.3)
The step affects zoom calculation when zooming with a mouse wheel, when pinch zooming, or when using zoomIn/zoomOut
These methods are available after initializing Panzoom.
• eventNames: Object
This object exposes the event names used by Panzoom, depending on the current browser's support for Pointer or Touch events.
| Name | Type |
|---|---|
down |
string |
move |
string |
up |
string |
▸ bind(): void
Bind the default down, move, and up event listeners to the Panzoom element.
This does not normally need to be called.
It gets called by default when creating a new Panzoom object,
but can be skipped with the noBind option.
const panzoom = Panzoom(elem, { noBind: true })
// ...
panzoom.bind()void
▸ destroy(): void
Remove all event listeners bound to the the Panzoom element
void
▸ getOptions(): PanzoomOptions
Returns a copy of the current options object
PanzoomOptions
▸ getPan(): Object
Get the current x/y translation
Object
| Name | Type |
|---|---|
x |
number |
y |
number |
▸ getScale(): number
Get the current scale
number
▸ pan(x, y, panOptions?): [CurrentValues](#CurrentValues)
Pan the Panzoom element to the given x and y coordinates
// Translates the element to 50px, 100px
panzoom.pan(50, 100)
// Pans the element right 10px and down 10px from its current position
panzoom.pan(10, 10, { relative: true })| Name | Type |
|---|---|
x |
string | number |
y |
string | number |
panOptions? |
PanOptions |
[CurrentValues](#CurrentValues)
▸ reset(resetOptions?): [CurrentValues](#CurrentValues)
Reset the pan and zoom to startX, startY, and startScale.
Animates by default, ignoring the global option.
Pass { animate: false } to override.
Reset ignores the disablePan, disableZoom, and panOnlyWhenZoomed options.
Pass { force: false } to override.
panzoom.reset()
panzoom.reset({ animate: false })| Name | Type |
|---|---|
resetOptions? |
PanzoomOptions |
[CurrentValues](#CurrentValues)
▸ resetStyle(): void
Reset the styles set on the Panzoom element and its parent (such as overflow, cursor, etc.)
panzoom.resetStyle()void
▸ setOptions(options?): void
Change any number of options on a Panzoom instance. Setting some options will have side-effects. For instance, changing the cursor option will also set the cursor style.
const panzoom = Panzoom(elem, { cursor: 'move' })
// ...
panzoom.setOptions({ cursor: 'default' })| Name | Type |
|---|---|
options? |
PanzoomOptions |
void
▸ setStyle(name, value): void
A convenience method for setting prefixed styles on the Panzoom element
| Name | Type |
|---|---|
name |
string |
value |
string |
void
▸ zoom(scale, zoomOptions?): [CurrentValues](#CurrentValues)
Zoom the Panzoom element to the given scale
panzoom.zoom(2.2)
panzoom.zoom(2.2, { animate: true })| Name | Type |
|---|---|
scale |
number |
zoomOptions? |
ZoomOptions |
[CurrentValues](#CurrentValues)
▸ zoomIn(zoomOptions?): [CurrentValues](#CurrentValues)
Zoom in using the predetermined increment set in options.
Animates by default, ignoring the global option.
Pass { animate: false } to override.
panzoom.zoomIn()
panzoom.zoomIn({ animate: false })| Name | Type |
|---|---|
zoomOptions? |
ZoomOptions |
[CurrentValues](#CurrentValues)
▸ zoomOut(zoomOptions?): [CurrentValues](#CurrentValues)
Zoom out using the predetermined increment set in options.
Animates by default, ignoring the global option.
Pass { animate: false } to override.
panzoom.zoomOut()
panzoom.zoomOut({ animate: false })| Name | Type |
|---|---|
zoomOptions? |
ZoomOptions |
[CurrentValues](#CurrentValues)
▸ zoomToPoint(scale, point, zoomOptions?): [CurrentValues](#CurrentValues)
Zoom the Panzoom element to a focal point using
the given pointer/touch/mouse event or constructed point.
The clientX/clientY values should be calculated
the same way as a pointermove event on the Panzoom element's parent.
panzoom.zoomToPoint(1.2, pointerEvent)| Name | Type |
|---|---|
scale |
number |
point |
Object |
point.clientX |
number |
point.clientY |
number |
zoomOptions? |
ZoomOptions |
[CurrentValues](#CurrentValues)
▸ zoomWithWheel(event, zoomOptions?): [CurrentValues](#CurrentValues)
Zoom the Panzoom element to a focal point using the given WheelEvent
This is a convenience function that may not handle all use cases.
Other cases should handroll solutions using the zoomToPoint
method or the zoom method's focal option.
Notes:
- the focal point zooming pan adjustment is
not affected by the
disablePanoption. - animate should not be used when zooming with the wheel, and is therefore always disabled.
// Bind to mousewheel
elem.parentElement.addEventListener('wheel', panzoom.zoomWithWheel)
// Bind to shift+mousewheel
elem.parentElement.addEventListener('wheel', function (event) {
if (!event.shiftKey) return
// Panzoom will automatically use `deltaX` here instead
// of `deltaY`. On a mac, the shift modifier usually
// translates to horizontal scrolling, but Panzoom assumes
// the desired behavior is zooming.
panzoom.zoomWithWheel(event)
})| Name | Type |
|---|---|
event |
WheelEvent |
zoomOptions? |
ZoomOptions |
[CurrentValues](#CurrentValues)
• Optional isSVG: boolean
• scale: number
• x: number
• y: number
The following events are available as custom events on the panzoom element using the native CustomEvent API. Add listeners the same way you would any other event.
elem.addEventListener('panzoomchange', (event) => {
console.log(event.detail) // => { x: 0, y: 0, scale: 1 }
})- The event object passed as an argument to the listener will always have a
detailobject with the following properties:- The current
xvalue - The current
yvalue - The current
scale - An
originalEventproperty with the original event that triggered the panzoom event, if applicable. For example, theoriginalEventproperty for apanzoomstartevent would be either apointerdown,touchstart, ormousedownevent.
- The current
- Events can be silenced when the
silentoption is set totrue, either globally or when passed topan, anyzoommethod, orreset. - Avoid putting too much logic in these event handlers as it could effect the performance of panning or zooming.
Fired when the user starts a move or pinch zoom gesture on mobile.
Fired whenever there is a pan, zoom, or reset. Note that direct calls to options.setTransform do not fire this event.
Fired whenever the zoom is changed by any Panzoom zoom method, directly or internally.
Fired whenever the pan is changed by the pan method, directly or internally.
Fired when the user finishes a move or finishes a pinch zoom gesture on mobile.
Fired whenever reset is called.