enhance(frontend): add pixelate mask effect

2 files changed, 149 insertions, 0 deletions

diff --git a/packages/frontend/src/utility/image-effector/fxs.ts b/packages/frontend/src/utility/image-effector/fxs.ts
index 83ec20823d..2b20cc1f99 100644
--- a/packages/frontend/src/utility/image-effector/fxs.ts
+++ b/packages/frontend/src/utility/image-effector/fxs.ts
@@ -20,6 +20,7 @@ import { FX_zoomLines } from './fxs/zoomLines.js';
 import { FX_blockNoise } from './fxs/blockNoise.js';
 import { FX_fill } from './fxs/fill.js';
 import { FX_blur } from './fxs/blur.js';
+import { FX_pixelate } from './fxs/pixelate.js';
 import type { ImageEffectorFx } from './ImageEffector.js';
 
 export const FXS = [
@@ -40,4 +41,5 @@ export const FXS = [
 	FX_blockNoise,
 	FX_fill,
 	FX_blur,
+	FX_pixelate,
 ] as const satisfies ImageEffectorFx<string, any>[];
diff --git a/packages/frontend/src/utility/image-effector/fxs/pixelate.ts b/packages/frontend/src/utility/image-effector/fxs/pixelate.ts
new file mode 100644
index 0000000000..d9a5f454f3
--- /dev/null
+++ b/packages/frontend/src/utility/image-effector/fxs/pixelate.ts
@@ -0,0 +1,147 @@
+/*
+ * SPDX-FileCopyrightText: syuilo and misskey-project
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+import { defineImageEffectorFx } from '../ImageEffector.js';
+import { i18n } from '@/i18n.js';
+
+const shader = `#version 300 es
+precision mediump float;
+
+const float PI = 3.141592653589793;
+const float TWO_PI = 6.283185307179586;
+const float HALF_PI = 1.5707963267948966;
+
+in vec2 in_uv;
+uniform sampler2D in_texture;
+uniform vec2 in_resolution;
+uniform vec2 u_offset;
+uniform vec2 u_scale;
+uniform bool u_ellipse;
+uniform float u_angle;
+uniform int u_samples;
+uniform float u_strength;
+out vec4 out_color;
+
+// TODO: pixelateの中心を画像中心ではなく範囲の中心にする
+// TODO: 画像のアスペクト比に関わらず各画素は正方形にする
+
+void main() {
+	if (u_strength <= 0.0) {
+		out_color = texture(in_texture, in_uv);
+		return;
+	}
+
+	float angle = -(u_angle * PI);
+	vec2 centeredUv = in_uv - vec2(0.5, 0.5) - u_offset;
+	vec2 rotatedUV = vec2(
+		centeredUv.x * cos(angle) - centeredUv.y * sin(angle),
+		centeredUv.x * sin(angle) + centeredUv.y * cos(angle)
+	) + u_offset;
+
+	bool isInside = false;
+	if (u_ellipse) {
+		vec2 norm = (rotatedUV - u_offset) / u_scale;
+		isInside = dot(norm, norm) <= 1.0;
+	} else {
+		isInside = rotatedUV.x > u_offset.x - u_scale.x && rotatedUV.x < u_offset.x + u_scale.x && rotatedUV.y > u_offset.y - u_scale.y && rotatedUV.y < u_offset.y + u_scale.y;
+	}
+
+	if (!isInside) {
+		out_color = texture(in_texture, in_uv);
+		return;
+	}
+
+	float dx = u_strength / 1.0;
+	float dy = u_strength / 1.0;
+	vec2 new_uv = vec2(
+		(dx * (floor((in_uv.x - 0.5 - (dx / 2.0)) / dx) + 0.5)),
+		(dy * (floor((in_uv.y - 0.5 - (dy / 2.0)) / dy) + 0.5))
+	) + vec2(0.5 + (dx / 2.0), 0.5 + (dy / 2.0));
+
+	vec4 result = vec4(0.0);
+	float totalSamples = 0.0;
+
+	// TODO: より多くのサンプリング
+	result += texture(in_texture, new_uv);
+	totalSamples += 1.0;
+
+	out_color = totalSamples > 0.0 ? result / totalSamples : texture(in_texture, in_uv);
+}
+`;
+
+export const FX_pixelate = defineImageEffectorFx({
+	id: 'pixelate',
+	name: i18n.ts._imageEffector._fxs.pixelate,
+	shader,
+	uniforms: ['offset', 'scale', 'ellipse', 'angle', 'strength', 'samples'] as const,
+	params: {
+		offsetX: {
+			label: i18n.ts._imageEffector._fxProps.offset + ' X',
+			type: 'number',
+			default: 0.0,
+			min: -1.0,
+			max: 1.0,
+			step: 0.01,
+			toViewValue: v => Math.round(v * 100) + '%',
+		},
+		offsetY: {
+			label: i18n.ts._imageEffector._fxProps.offset + ' Y',
+			type: 'number',
+			default: 0.0,
+			min: -1.0,
+			max: 1.0,
+			step: 0.01,
+			toViewValue: v => Math.round(v * 100) + '%',
+		},
+		scaleX: {
+			label: i18n.ts._imageEffector._fxProps.scale + ' W',
+			type: 'number',
+			default: 0.5,
+			min: 0.0,
+			max: 1.0,
+			step: 0.01,
+			toViewValue: v => Math.round(v * 100) + '%',
+		},
+		scaleY: {
+			label: i18n.ts._imageEffector._fxProps.scale + ' H',
+			type: 'number',
+			default: 0.5,
+			min: 0.0,
+			max: 1.0,
+			step: 0.01,
+			toViewValue: v => Math.round(v * 100) + '%',
+		},
+		ellipse: {
+			label: i18n.ts._imageEffector._fxProps.circle,
+			type: 'boolean',
+			default: false,
+		},
+		angle: {
+			label: i18n.ts._imageEffector._fxProps.angle,
+			type: 'number',
+			default: 0,
+			min: -1.0,
+			max: 1.0,
+			step: 0.01,
+			toViewValue: v => Math.round(v * 90) + '°',
+		},
+		strength: {
+			label: i18n.ts._imageEffector._fxProps.strength,
+			type: 'number',
+			default: 0.2,
+			min: 0.0,
+			max: 0.5,
+			step: 0.01,
+		},
+	},
+	main: ({ gl, u, params }) => {
+		gl.uniform2f(u.offset, params.offsetX / 2, params.offsetY / 2);
+		gl.uniform2f(u.scale, params.scaleX / 2, params.scaleY / 2);
+		gl.uniform1i(u.ellipse, params.ellipse ? 1 : 0);
+		gl.uniform1f(u.angle, params.angle / 2);
+		gl.uniform1f(u.strength, params.strength * params.strength);
+		gl.uniform1i(u.samples, 256);
+	},
+});