javascript - P5.js Draw() 函数在 AngularJS 指令中未按预期工作
问题描述
我正在尝试将 p5.js 库集成到我的 AngularJS 应用程序中,让我的代码在指令中运行。
在我的纯 JavaScript 文件中,我能够在全局导入 p5 库后运行 draw() 方法。
我的原始代码(不是问题):
var mic
var playButton
var volHistory = []
var micIsOn = false
function setup(){
createCanvas(400, 150)
createButtons()
mic = new p5.AudioIn()
}
function draw(){
background(245)
stroke(0, 109, 203)
//populate volHistory
if(micIsOn){
var vol = mic.getLevel()
//check to see if array is empty, if it is empty we do not want to push 0 volume
if(volHistory.length > 0 && vol > 0){
volHistory.push(vol)
//if recording has started, we can now take in vol
} else if(vol > 0) {
volHistory.push(vol)
console.log(volHistory.length)
}
}
//iterate through volHistory and draw
fill(0, 109, 203)
var barWidth = 2;
var offsetWidth = 5;
var offset = 5;
for(var i = 0; i < volHistory.length; i++){
var barHeight = map(volHistory[i], 0, 1, 1, height)
rect(i + offset, (height/2.0) - (barHeight/2.0), barWidth, barHeight, 15);
offset += offsetWidth;
}
//moves wavelength 1 index at a time and account for bar width and offset width
if(volHistory.length * (offsetWidth + barWidth) > width){
volHistory.splice(0, 1)
}
//draw vertical line
stroke(250, 30, 100)
line(volHistory.length + offset, 0, volHistory.length + offset, height)
}
function createButtons(){
playButton = createButton("<img style='width: 50px' src='playbutton.png'/>")
playButton.mousePressed(toggleRecord)
playButton.position(162, 50)
playButton.style("background-color", color(0,0,0,0))
playButton.style("border", 0)
}
//toggle recording of audio
function toggleRecord(){
if(!micIsOn){
mic.start()
micIsOn = true
} else {
mic.stop()
micIsOn = false
}
}
上面的代码让我创建了一个声音可视化器,它接入用户的麦克风,绘制一个显示他们声音级别的画布。看起来像这样:
但是,当我尝试在 Angular 指令中使用该库时,似乎无法让 draw() 方法按预期运行。draw() 函数不会像在 Angular 指令之外那样连续运行。
我得到的最接近的工作是通过$watch
在变量上创建一个来跟踪用户是否正在录制。如果 isRecording 为真,我将使用 setInterval 连续调用 draw()。不幸的是,这似乎是对 draw() 方法的不当使用,因为它应该在第一次执行后自行连续执行其中的代码。
角代码:
(function () {
angular.module('icSdkPwp').directive('icAudioRecordingUpload', icAudioRecordingUpload);
function icAudioRecordingUpload($stateSvc, $rS, $utilSvc) {
return {
scope: {
model: '=',
config: '=',
updateState: '='
},
link: function ($s, e, a) {
$s.hasRecording = false;
$s.isRecording = false;
$s.recordingPaused = false;
$s.recordingProcessing = false;
$s.volHistory = []
$s.micIsOn = false
$s.p5mic = null
$s.playButton = null
var gumStream;
var rec;
var input;
var AudioContext = window.AudioContext || window.webkitAudioContext;
var audioContext
$s.startRecording = function(e) {
if($s.recordingProcessing)
return;
var constraints = { audio: true, video:false }
setup()
$s.isRecording = true;
navigator.mediaDevices.getUserMedia(constraints)
.then(function(stream) {
audioContext = new AudioContext();
gumStream = stream;
input = audioContext.createMediaStreamSource(stream);
rec = new Recorder(input,{numChannels:2})
rec.record()
}).catch(function(err) {
$s.isRecording = true;
});
}
var redrawInt = null;
$s.$watch("isRecording", function (n, o, s) {
if(s.isRecording){
redrawInt = setInterval(function(){
draw()
},0);
}
else{
clearInterval(redrawInt);
}
});
function setup(){
createCanvas(400, 150)
$s.p5mic = new p5.AudioIn()
$s.p5mic.start()
$s.micIsOn = true
background(245)
}
function draw(){
stroke(0, 109, 203)
//populate volHistory
if($s.isRecording){
var vol = $s.p5mic.getLevel()
//check to see if array is empty, if it is empty we do not want to push 0 volume
if($s.volHistory.length > 0 && vol > 0){
$s.volHistory.push(vol)
//if recording has started, we can now take in vol
} else if(vol > 0) {
$s.volHistory.push(vol)
}
}
//iterate through volHistory and draw
fill(0, 109, 203)
var barWidth = 2;
var offsetWidth = 5;
var offset = 5;
for(var i = 0; i < $s.volHistory.length; i++){
var barHeight = map($s.volHistory[i], 0, 1, 1, height)
rect(i + offset, (height/2.0) - (barHeight/2.0), barWidth, barHeight, 15);
offset += offsetWidth;
}
//moves wavelength 1 index at a time and account for bar width and offset width
if($s.volHistory.length * (offsetWidth + barWidth) > width){
$s.volHistory.splice(0, 1)
}
//draw vertical line
stroke(250, 30, 100)
// debugger
line($s.volHistory.length + offset, 0, $s.volHistory.length + offset, height)
}
}
};
}
}());
调用 startRecording() 的按钮,启动进程
<div class="IX_recordControls clearfix">
<div class="rcrow row1">
<div ng-click="recordingProcessing || startRecording($event)"
ng-if="!hasRecording">
</div>
</div>
这给了我一个非常奇怪的画布,我认为这是意料之中的,因为我不应该多次调用 draw(),但我找不到一种方法让它一次调用并连续运行。
这绝对看起来像是范围的问题,其中 draw() 方法无法执行自己的循环。