feat: MFM Sparkle animation (#7813)

* Add sparkle mfm animation ✨

* Cleanup sparkle effect

+ spaces -> tabs and other codestyle
+ use proper image
+ listen for resizes
+ use font-size to determine particle size (for fun with x2/3/4 stacking)

locales/en-US.yml

@@ -899,6 +899,8 @@ _mfm:
   fontDescription: "Sets the font to display contents in."
   rainbow: "Rainbow"
   rainbowDescription: "Makes the content appear in rainbow colors."
+  sparkle: "Sparkle"
+  sparkleDescription: "Infuses a sparkling animation"
 _reversi:
   reversi: "Reversi"
   gameSettings: "Game settings"

src/client/components/mfm.ts

@@ -8,6 +8,7 @@ import { concat } from '@client/../prelude/array';
 import MkFormula from '@client/components/formula.vue';
 import MkCode from '@client/components/code.vue';
 import MkGoogle from '@client/components/google.vue';
+import MkSparkle from '@client/components/sparkle.vue';
 import MkA from '@client/components/global/a.vue';
 import { host } from '@client/config';
 
@@ -169,6 +170,19 @@ export default defineComponent({
 							style = this.$store.state.animatedMfm ? 'animation: mfm-rainbow 1s linear infinite;' : '';
 							break;
 						}
+						case 'sparkle': {
+							if (!this.$store.state.animatedMfm) {
+								return genEl(token.children);
+							}
+							let count = token.props.args.count ? parseInt(token.props.args.count) : 10;
+							if (count > 100) {
+								count = 100;
+							}
+							const speed = token.props.args.speed ? parseFloat(token.props.args.speed) : 1;
+							return h(MkSparkle, {
+								count, speed,
+							}, genEl(token.children));
+						}
 					}
 					if (style == null) {
 						return h('span', {}, ['[', token.props.name, ...genEl(token.children), ']']);

src/client/components/sparkle.vue

+<template>
+<span class="mk-sparkle">
+	<span ref="content">
+		<slot></slot>
+	</span>
+	<canvas ref="canvas"></canvas>
+</span>
+</template>
+
+<script lang="ts">
+import { defineComponent } from 'vue';
+import * as os from '@client/os';
+
+const sprite = new Image();
+sprite.src = "/static-assets/client/sparkle-spritesheet.png";
+
+
+export default defineComponent({
+	props: {
+		count: {
+			type: Number,
+			required: true,
+		},
+		speed: {
+			type: Number,
+			required: true,
+		},
+	},
+	data() {
+		return {
+			sprites: [0,6,13,20],
+			particles: [],
+			anim: null,
+			ctx: null,
+		};
+	},
+	methods: {
+		createSparkles(w, h, count) {
+			var holder = [];
+
+			for (var i = 0; i < count; i++) {
+
+				const color = '#' + ('000000' + Math.floor(Math.random() * 16777215).toString(16)).slice(-6);
+
+				holder[i] = {
+					position: {
+						x: Math.floor(Math.random() * w),
+						y: Math.floor(Math.random() * h)
+					},
+					style: this.sprites[ Math.floor(Math.random() * 4) ],
+					delta: {
+						x: Math.floor(Math.random() * 1000) - 500,
+						y: Math.floor(Math.random() * 1000) - 500
+					},
+					color: color,
+					opacity: Math.random(),
+				};
+
+			}
+
+			return holder;
+		},
+		draw(time) {
+			this.ctx.clearRect(0, 0, this.$refs.canvas.width, this.$refs.canvas.height);
+			this.ctx.beginPath();
+
+			const particleSize = Math.floor(this.fontSize / 2);
+			this.particles.forEach((particle) => {
+				var modulus = Math.floor(Math.random()*7);
+
+				if (Math.floor(time) % modulus === 0) {
+					particle.style = this.sprites[ Math.floor(Math.random()*4) ];
+				}
+
+				this.ctx.save();
+				this.ctx.globalAlpha = particle.opacity;
+				this.ctx.drawImage(sprite, particle.style, 0, 7, 7, particle.position.x, particle.position.y, particleSize, particleSize);
+
+				this.ctx.globalCompositeOperation = "source-atop";
+				this.ctx.globalAlpha = 0.5;
+				this.ctx.fillStyle = particle.color;
+				this.ctx.fillRect(particle.position.x, particle.position.y, particleSize, particleSize);
+
+				this.ctx.restore();
+			});
+			this.ctx.stroke();
+		},
+		tick() {
+			this.anim = window.requestAnimationFrame((time) => {
+				if (!this.$refs.canvas) {
+					return;
+				}
+				this.particles.forEach((particle) => {
+					if (!particle) {
+						return;
+					}
+					var randX = Math.random() > Math.random() * 2;
+					var randY = Math.random() > Math.random() * 3;
+
+					if (randX) {
+						particle.position.x += (particle.delta.x * this.speed) / 1500;
+					}
+
+					if (!randY) {
+						particle.position.y -= (particle.delta.y * this.speed) / 800;
+					}
+
+					if( particle.position.x > this.$refs.canvas.width ) {
+						particle.position.x = -7;
+					} else if (particle.position.x < -7) {
+						particle.position.x = this.$refs.canvas.width;
+					}
+
+					if (particle.position.y > this.$refs.canvas.height) {
+						particle.position.y = -7;
+						particle.position.x = Math.floor(Math.random() * this.$refs.canvas.width);
+					} else if (particle.position.y < -7) {
+						particle.position.y = this.$refs.canvas.height;
+						particle.position.x = Math.floor(Math.random() * this.$refs.canvas.width);
+					}
+
+					particle.opacity -= 0.005;
+
+					if (particle.opacity <= 0) {
+						particle.opacity = 1;
+					}
+				});
+
+				this.draw(time);
+
+				this.tick();
+			});
+		},
+		resize() {
+			if (this.$refs.content) {
+				const contentRect = this.$refs.content.getBoundingClientRect();
+				this.fontSize = parseFloat(getComputedStyle(this.$refs.content).fontSize);
+				const padding = this.fontSize * 0.2;
+
+				this.$refs.canvas.width = parseInt(contentRect.width + padding);
+				this.$refs.canvas.height = parseInt(contentRect.height + padding);
+
+				this.particles = this.createSparkles(this.$refs.canvas.width, this.$refs.canvas.height, this.count);
+			}
+		},
+	},
+	mounted() {
+		this.ctx = this.$refs.canvas.getContext('2d');
+
+		new ResizeObserver(this.resize).observe(this.$refs.content);
+
+		this.resize();
+		this.tick();
+	},
+	updated() {
+		this.resize();
+	},
+	destroyed() {
+		window.cancelAnimationFrame(this.anim);
+	},
+});
+</script>
+
+<style lang="scss" scoped>
+.mk-sparkle {
+	position: relative;
+	display: inline-block;
+
+	> span {
+		display: inline-block;
+	}
+
+	> canvas {
+		position: absolute;
+		top: -0.1em;
+		left: -0.1em;
+		pointer-events: none;
+	}
+}
+</style>

src/client/pages/mfm-cheat-sheet.vue

@@ -271,6 +271,16 @@
 			</div>
 		</div>
 	</div>
+	<div class="section _block">
+		<div class="title">{{ $ts._mfm.sparkle }}</div>
+		<div class="content">
+			<p>{{ $ts._mfm.sparkleDescription }}</p>
+			<div class="preview">
+				<Mfm :text="preview_sparkle"/>
+				<MkTextarea v-model="preview_sparkle"><span>MFM</span></MkTextarea>
+			</div>
+		</div>
+	</div>
 </div>
 </template>
 
@@ -294,7 +304,7 @@ export default defineComponent({
 			preview_hashtag: '#test',
 			preview_url: `https://example.com`,
 			preview_link: `[${this.$ts._mfm.dummy}](https://example.com)`,
-			preview_emoji: `:${this.$instance.emojis[0].name}:`,
+			preview_emoji: this.$instance.emojis.length ? `:${this.$instance.emojis[0].name}:` : `:emojiname:`,
 			preview_bold: `**${this.$ts._mfm.dummy}**`,
 			preview_small: `<small>${this.$ts._mfm.dummy}</small>`,
 			preview_center: `<center>${this.$ts._mfm.dummy}</center>`,
@@ -317,6 +327,7 @@ export default defineComponent({
 			preview_x4: `$[x4 🍮]`,
 			preview_blur: `$[blur ${this.$ts._mfm.dummy}]`,
 			preview_rainbow: `$[rainbow 🍮]`,
+			preview_sparkle: `$[sparkle 🍮]`,
 		}
 	},
 });