misskey/packages/frontend/src/components/MkImgWithBlurhash.vue
2023-01-14 20:31:48 +09:00

77 lines
1.3 KiB
Vue

<template>
<div :class="[$style.root, { [$style.cover]: cover }]" :title="title">
<canvas v-if="!loaded" ref="canvas" :class="$style.canvas" :width="size" :height="size" :title="title"/>
<img v-if="src" :class="$style.img" :src="src" :title="title" :alt="alt" @load="onLoad"/>
</div>
</template>
<script lang="ts" setup>
import { onMounted } from 'vue';
import { decode } from 'blurhash';
const props = withDefaults(defineProps<{
src?: string | null;
hash?: string;
alt?: string;
title?: string | null;
size?: number;
cover?: boolean;
}>(), {
src: null,
alt: '',
title: null,
size: 64,
cover: true,
});
const canvas = $shallowRef<HTMLCanvasElement>();
let loaded = $ref(false);
function draw() {
if (props.hash == null) return;
const pixels = decode(props.hash, props.size, props.size);
const ctx = canvas.getContext('2d');
const imageData = ctx!.createImageData(props.size, props.size);
imageData.data.set(pixels);
ctx!.putImageData(imageData, 0, 0);
}
function onLoad() {
loaded = true;
}
onMounted(() => {
draw();
});
</script>
<style lang="scss" module>
.root {
position: relative;
width: 100%;
height: 100%;
&.cover {
> .img {
object-fit: cover;
}
}
}
.canvas,
.img {
display: block;
width: 100%;
height: 100%;
}
.canvas {
position: absolute;
object-fit: cover;
}
.img {
object-fit: contain;
}
</style>