A phosphor green filter to your webcam
// ==UserScript==
// @name Google Meet Matrix Rain prank
// @namespace http://tampermonkey.net/
// @version 1.1
// @description A phosphor green filter to your webcam
// @author Xing
// @match https://meet.google.com/*
// @grant none
// ==/UserScript==
(async function() {
'use strict'
const video = document.createElement('video')
video.style='position:fixed;left:0;top:0;height:50px;z-index:9999999;background:black';
video.setAttribute('playsinline','');
video.setAttribute('autoplay','');
const toggle = document.createElement('input')
toggle.type='checkbox'
toggle.checked=true
toggle.style='position:fixed;left:0;top:0;width:50px;height:10px;z-index:9999999';
class mercatorMediaStream extends MediaStream {
constructor(old_stream) {
super(old_stream)
const camera = document.createElement('canvas')
const matrix = document.createElement('canvas')
const comp = document.createElement('canvas')
// Matrix rain
const katakana = `1234567890ァアィイゥウェエォオカガキギクグケゲコゴサザシジスズセゼソゾタダチヂッツヅテデトドナニヌネノハバパヒビピフブプヘベペホボポマミムメモャヤュユョヨラリルレロヮワヰヱヲンヴヵヶヷヸヹヺーヽヾヿ`;
document.body.appendChild(video);
document.body.appendChild(toggle);
const constraints = {audio: false, video: true};
video.srcObject = old_stream
const old_stream_settings = old_stream.getVideoTracks()[0].getSettings()
const w = old_stream_settings.width
const h = old_stream_settings.height
const aspect_ratio = w/h
const r = w/64
matrix.width = w*1.5
matrix.height = h
comp.width = w
comp.height = h
camera.width = w/r
camera.height = h/r
const matrix_ctx = matrix.getContext('2d')
const camera_ctx = camera.getContext('2d')
const comp_ctx = comp.getContext('2d')
matrix_ctx.font = 0.9*r+'px monospace'
matrix_ctx.textAlign = 'center'
matrix_ctx.translate(w*1.5, 0)
matrix_ctx.scale(-1,1)
camera_ctx.filter = 'brightness(0.8) contrast(2.5)'
matrix_ctx.fillStyle='#020'
matrix_ctx.fillRect(0,0,w*1.5,h)
matrix_ctx.fillStyle = '#8f8'
matrix_ctx.lineWidth = r/10
matrix_ctx.strokeStyle = '#080'
matrix_ctx.textBaseline = 'ideographic'
const text_offset = r*1.5/2
for(let x = text_offset; x < w*1.5+1; x+=r*1.5){
for(let y = 0; y < h+1; y+=r){
const rand_text = katakana[Math.floor(Math.random()*katakana.length)]
matrix_ctx.strokeText(rand_text,x,y)
matrix_ctx.fillText(rand_text,x,y)
}
}
let rainx = 0
let rainy = 0
let rain_text = ['Z',text_offset,0]
function draw(){
if(toggle.checked){
comp_ctx.imageSmoothingEnabled = false
matrix_ctx.fillStyle = '#020'
matrix_ctx.fillRect(rainx,rainy,r*1.5,-r)
matrix_ctx.strokeStyle = '#080'
matrix_ctx.fillStyle = '#8f8'
matrix_ctx.strokeText(...rain_text)
matrix_ctx.fillText(...rain_text)
rainx = Math.floor(Math.random()*(w+1)/r)*r*1.5
rainy = Math.floor(Math.random()*(h+1)/r)*r
rain_text = [
katakana[Math.floor(Math.random()*katakana.length)],
rainx+text_offset,
rainy
]
matrix_ctx.strokeStyle = '#0f0'
matrix_ctx.fillStyle = '#fff'
matrix_ctx.strokeText(...rain_text)
matrix_ctx.fillText(...rain_text)
camera_ctx.drawImage(video, 0, 0, w/r, h/r)
comp_ctx.clearRect(0,0,w,h)
comp_ctx.globalCompositeOperation = 'source_over'
comp_ctx.drawImage(camera,0,0,w,h)
comp_ctx.globalCompositeOperation = 'color'
comp_ctx.drawImage(matrix,0,0,w,h)
comp_ctx.globalCompositeOperation = 'multiply'
comp_ctx.drawImage(matrix,0,0,w,h)
} else {
comp_ctx.globalCompositeOperation = 'source_over'
comp_ctx.clearRect(0,0,w,h)
comp_ctx.drawImage(video,0,0,w,h)
}
requestAnimationFrame(draw)
}
draw()
return comp.captureStream(10)
}
}
async function newGetUserMedia(constraints) {
if (constraints && constraints.video && !constraints.audio ) {
return new mercatorMediaStream(await navigator.mediaDevices.oldGetUserMedia(constraints))
} else {
return navigator.mediaDevices.oldGetUserMedia(constraints)
}
}
MediaDevices.prototype.oldGetUserMedia = MediaDevices.prototype.getUserMedia
MediaDevices.prototype.getUserMedia = newGetUserMedia
})()