@nine-slice-frame/vue

Nine-slice scaling component for Vue 3 using CSS border-image.

What is Nine-Slice Scaling?

Nine-slice scaling divides an image into 9 sections, allowing it to scale to any size while preserving corner details and preventing distortion. Perfect for UI frames, borders, panels, and buttons that need to scale dynamically.

┌─────────┬───────────┬─────────┐
│ Corner  │ Top Edge  │ Corner  │
│ (Fixed) │ (Scale H) │ (Fixed) │
├─────────┼───────────┼─────────┤
│  Left   │  Center   │  Right  │
│  Edge   │ (Scale    │  Edge   │
│(Scale V)│  Both)    │(Scale V)│
├─────────┼───────────┼─────────┤
│ Corner  │ Bottom    │ Corner  │
│ (Fixed) │   Edge    │ (Fixed) │
└─────────┴───────────┴─────────┘

Why Nine-Slice Scaling?

The Problem: Traditional image scaling stretches the entire image uniformly, distorting corners, borders, and decorative elements. This makes UI elements look unprofessional and breaks visual consistency.

The Solution: Nine-slice scaling keeps corners and edges crisp while only stretching the middle sections. This means:

Single image, infinite sizes - One asset works for buttons, dialogs, and panels of any dimension
Pixel-perfect corners - Ornate borders and rounded corners stay sharp at any scale
Smaller file sizes - No need for multiple image variants for different sizes
Ideal for pixel art - Preserves the crisp aesthetic of retro-style UIs
CSS-native performance - Uses browser-native border-image, no canvas or WebGL overhead

Common Use Cases:

Game UI frames and dialog boxes
Decorative borders and panels
Scalable buttons with ornate edges
Retro/pixel art interfaces
Dynamic content containers

Why This Library?

Zero Dependencies - No runtime dependencies beyond Vue. This package only requires Vue 3 as a peer dependency.

Incredibly Small - Minimal bundle impact: 1.33KB / 0.67KB gzipped

Native Performance - Uses browser-native CSS border-image property, not canvas rendering or heavy image manipulation libraries. Fast, efficient, and hardware-accelerated.

Framework-Agnostic API - Same simple, consistent API across all frameworks:

Installation

npm install @nine-slice-frame/vue
# or
pnpm add @nine-slice-frame/vue
# or
yarn add @nine-slice-frame/vue

Usage

<script setup lang="ts">
import { NineSliceFrame } from '@nine-slice-frame/vue';
</script>

<template>
  <NineSliceFrame
    image-path="/ui/frame.png"
    :slice="7"
    :border-width="5"
    repeat="stretch"
    :fill="true"
    :pixelated="true"
  >
    <p>Your content here</p>
  </NineSliceFrame>
</template>

Props

Prop	Type	Default	Description
`image-path`	`string`	required	Path to the image (relative to public folder)
`slice`	`number \| object`	`8`	Slice values - number for uniform, or `{ top, right, bottom, left }` for per-edge
`border-width`	`number`	`5`	Visual border width in pixels
`repeat`	`'stretch' \| 'repeat' \| 'round' \| 'space'`	`'stretch'`	Border repeat mode
`fill`	`boolean`	`true`	Use 'fill' to show center of image as background
`pixelated`	`boolean`	`true`	Use pixelated rendering for pixel art
`class`	`string`	`''`	Additional CSS class names
`style`	`StyleValue`	`{}`	Additional inline styles

Note: Vue uses kebab-case for props in templates (image-path, border-width).

Advanced Usage

Different Slice Values Per Edge

<template>
  <NineSliceFrame
    image-path="/ui/fancy-frame.png"
    :slice="{ top: 10, right: 8, bottom: 10, left: 8 }"
    :border-width="6"
  >
    Content with asymmetric border
  </NineSliceFrame>
</template>

Custom Styling

<template>
  <NineSliceFrame
    image-path="/ui/frame.png"
    :slice="8"
    :border-width="10"
    class="my-custom-frame"
    :style="{ padding: '20px', minHeight: '200px' }"
  >
    Styled content
  </NineSliceFrame>
</template>

JSPM