React Morpheus
A controlled React component for morphing one UI state into another.
React Morpheus exists for interfaces where a control should become the next piece of UI instead of opening a detached popover. The component keeps the source surface, destination surface, and overlay explicit. Your app still owns state and content; Morpheus owns the measured transition between those two surfaces.
Installation
bun add react-morpheus cuelume
npm i react-morpheus cuelume
yarn add react-morpheus cuelume
Cuelume is a required peer dependency; sound playback remains opt-in. It synthesizes cues with the Web Audio API, so React Morpheus does not bundle audio files.
Usage
Import the component and stylesheet, keep the open state in your app, and pass both surfaces to Morpheus.
import { useState } from "react";
import {
Morpheus,
MorphAnchor,
morphSpringPresets,
} from "react-morpheus";
import "react-morpheus/style.css";
function Example() {
const [expanded, setExpanded] = useState(false);
const source = (
<button type="button" onClick={() => setExpanded(true)}>
Open menu
</button>
);
return (
<Morpheus
anchor={MorphAnchor.TopMiddle}
expanded={expanded}
onClose={() => setExpanded(false)}
openSound="bloom"
closeSound="droplet"
overlayColor="#0f172a"
overlayOpacity={0.18}
overlayBlur={3}
overlayZIndex={1200}
viewportPadding={16}
spring={morphSpringPresets.smooth}
collapsedContent={source}
expandedContent={
<section>
<h2>San Francisco</h2>
<p>Context, actions, and details live here.</p>
<button type="button" onClick={() => setExpanded(false)}>
Close
</button>
</section>
}
/>
);
}
Morpheus does not manage its own open state. Opening is the responsibility of
the source component's own click handler. Overlay clicks call onClose; update
your controlled state there. Use beforeClose and afterClose for work that
should run around the closing animation.
What Morpheus Animates
Morpheus measures the first HTML element rendered by collapsedContent and
expandedContent, then animates between these values:
| Area | Animated values |
|---|---|
| Geometry | Width, height, and the anchored screen position |
| Surface | Background color, border color, border width, and border radius |
| Content | Opacity, position, and uniform scale so content keeps its proportions |
Border style is copied from each endpoint and switches rather than interpolating smoothly. Other CSS properties, such as box shadow, filter, typography, margin, and padding, are not independently interpolated.
Apply the surface background, border, and radius to the root element of each content state. Morpheus reads their computed CSS values, so styles from classes, stylesheets, and inline declarations are all supported.
Sounds
Use openSound and closeSound to add Cuelume cues to the controlled state
transition. React Morpheus calls Cuelume directly; you do not need to call
bind() or play() yourself.
<Morpheus
expanded={expanded}
openSound="bloom"
closeSound="droplet"
// ...the remaining props
/>
Each configured cue plays once when expanded changes. The initial render is
silent, including when expanded is initially true. Omit either prop to keep
that direction silent.
Both props accept Cuelume's SoundName values:
arrival, bloom, chime, droplet, error, loading, page, press,
pulse, ready, release, scan, sparkle, success, tick, toggle, and
whisper.
Props
| Prop | Type | Required | Notes |
|---|---|---|---|
anchor | MorphAnchor | Required | The edge or point that stays visually anchored. |
expanded | boolean | Required | Controlled open state owned by your app. |
onClose | () => void | Optional | Called when the overlay requests closing. Use it to update your controlled open state. |
beforeClose | () => void | Optional | Called when the closing animation starts, after expanded has changed to false. Useful for close-intent side effects. |
afterClose | () => void | Optional | Called after the closing animation completes. |
openSound | SoundName | Optional | Cuelume sound played once when expanded changes to true. |
closeSound | SoundName | Optional | Cuelume sound played once when expanded changes to false. |
collapsedContent | ReactNode | Required | The source surface Morpheus measures, renders, and uses as the opener. |
expandedContent | ReactNode | Required | The destination surface Morpheus measures and animates into. |
className | string | Optional | Classes applied to the root wrapper. Useful for block layout and responsive width constraints. |
shellClassName | string | Optional | Classes applied directly to the animated shell, including when it is portalled. |
portalContainer | HTMLElement | null | Optional | Portal root for the expanded surface. Defaults to document.body after mount; pass null for legacy inline rendering. |
viewportPadding | number | Optional | Minimum viewport gutter for the expanded shell. Defaults to 16. |
overlayColor | string | Optional | Backdrop color shown while expanded. |
overlayOpacity | number | Optional | Backdrop opacity from 0 to 1. |
overlayBlur | number | Optional | Backdrop blur in pixels. |
overlayZIndex | number | Optional | Stacking level for the expanded surface. Defaults to 1000; the overlay renders one layer below it. |
spring | Transition | Optional | Framer Motion transition. Pass your own transition or use morphSpringPresets. |
Pitfalls
Responsiveness
Let the collapsed trigger keep its natural size. Morpheus reads that box before animating to the expanded surface.
Put responsive width rules on className, such as viewport-bound max widths, so
the animated shell has stable constraints on narrow screens.
Pick an anchor that matches the source location. Top anchors feel right for menus opening below a trigger; bottom anchors feel right for surfaces opening upward; middle anchors feel better for centered inspectors or command surfaces.
Parent Container Overflow
Expanded surfaces and their overlays portal to document.body by default, so
they can escape clipped, transformed, and independently stacked ancestors. The
collapsed source remains in its original layout position. Pass another
document-level portalContainer when needed, or null to opt into the legacy
inline behavior.
Targets are clamped to the viewport using viewportPadding. When their natural
size is larger than the available viewport, the shell stays bounded and becomes
scrollable after the opening animation settles.
Stacking
overlayZIndex controls the portalled expanded surface. The overlay renders one
layer below it so apps can move the whole morphing stack above their own chrome.
Without this prop, Morpheus uses surface 1000 and overlay 999.
Development
example.html is a small local playground for trying Morpheus in a browser
without setting up an app shell. Use it to check the default interaction,
anchors and overlay behavior while changing the component.
Scripts
bun run buildbuilds declarations, bundled ESM output, and CSS.bun run checkruns TypeScript without emitting files.bun run publish:npmbuilds and publishes to npm.bun run release:patchbumps the patch version, builds, tags, and publishes.bun run release:minorbumps the minor version, builds, tags, and publishes.bun run release:majorbumps the major version, builds, tags, and publishes.
Credits
Inspired by Family Wallet and Benji Taylor's Family Values post.
License
Released under the MIT License.
