Prism music visualizer

index.html

.musicControls
    input#audiofile(type='file')
    //- button.listenButton ...or listen to one of mine // Silly CORS
    button.playPauseButton ▶
label#loading(for="audiofile") Select an audio file...

// This should match the values in the js
- var maxSideNum = 24
- var maxRectangleNum = 24

.prism
    - for (var x = 0; x < maxSideNum; x++)
        .side.hide
            - for (var y = 0; y < maxRectangleNum; y++)
                .rectangle.hide

Prism music visualizer.markdown

Prism music visualizer

My first music visualizer! Made using DOM with a lot of customization ability. Play with the controls and have some fun!

For solid colors (including animating it through the spectrum), the darks are the lows and the light ones are the highs. For the rainbow configuration, the red is low and pink is high.

Based on https://24.media.tumblr.com/cca3fc8094b89dc1a597e039a413c0f4/tumblr_n4euxkZcjo1sns7veo1_500.gif

A Pen by Zach Saucier on CodePen.

License.

script.js

var maxSideNum = 24,
    maxRectangleNum = 24;

// Dat.gui setup
var Options = function() {
    this.height = 400;
    this.radius = 185;
    this.sideCount = 12;
    
    this.rectangleCount = 12;
    this.rectangleWidth = 80;
    this.vertMargin = 10;
    this.borderWidth = 3;
    
    this.color = 200;
    this.solidBG = false;
    this.rainbowMode = false;
    this.animateThroughSpectrum = false;
    this.fade = false;
};


window.onload = function() {
    // dat.gui setup
    var myOptions = new Options(),
        gui = new dat.GUI(),
        f1 = gui.addFolder('Prism Controls'),
        f2 = gui.addFolder('Rectangle Controls'),
        f3 = gui.addFolder('Color Controls'),
        
        mySideCount = f1.add(myOptions, 'sideCount', 3, maxSideNum).step(1),
        myRadius = f1.add(myOptions, 'radius', 30, 600).step(15),
        myHeight = f1.add(myOptions, 'height', 50, 750).step(50),
        
        myRectangleCount = f2.add(myOptions, 'rectangleCount', 3, maxRectangleNum).step(1),
        myRectangleWidth = f2.add(myOptions, 'rectangleWidth', 1, 100).step(5),
        myVertMargin = f2.add(myOptions, 'vertMargin', 0, 15).step(1),
        myBorderWidth = f2.add(myOptions, 'borderWidth', 0, 15).step(1),
        
        myColor = f3.add(myOptions, 'color', 0, 360).step(1),
        mySolidBG = f3.add(myOptions, 'solidBG'),
        myRainbow = f3.add(myOptions, 'rainbowMode'),
        myAnimateThroughSpectrum = f3.add(myOptions, 'animateThroughSpectrum'),
        myFade = f3.add(myOptions, 'fade');
    
    f2.open();
    
    var audio,
        analyser,
        audioctx,
        sourceNode,
        stream;

    var audioInput = document.getElementById('audiofile'),
        listenButton = document.querySelector(".listenButton"),
        playPauseButton = document.querySelector(".playPauseButton");

    var c = 0, // Used to change color over time
        paused = true;
  
    /*var myMusic = [
        "http://zachsaucier.com/music/Initiation.mp3",
        "http://zachsaucier.com/music/High%20Tide.mp3",
        "http://zachsaucier.com/music/Dolphin%20Style.mp3",
        "http://zachsaucier.com/music/King.mp3"
    ];*/
    
    var prism = document.querySelector(".prism"),
        sides = document.querySelectorAll(".side"),
        rectangleArray = [maxSideNum],
        lastTime = Date.now(),
        timeGap = 50;
    
    function rectangleSetup() {
        for(var i = 0; i < maxSideNum; i++) {
            rectangleArray[i] = sides[i].querySelectorAll(".rectangle");
        }
    }
    rectangleSetup();
    
    
    
    // dat.gui listeners
    
    // f1 listeners
    function sideCountChange(newCount) {
        [].forEach.call(sides, function(elem, i) {
            if(i < myOptions.sideCount) {
                // The circle is inscribed inside of the prism, so we can use this formula to calculate the side length
                var sideLength = 2 * (myOptions.radius) * Math.tan(Math.PI / newCount);
                prism.style.width = sideLength + "px";
                prism.style.left = "calc(50% - " + sideLength / 2 + "px)";
                
                sides[i].style.transform = "rotateY(" + i * (360 / newCount) + "deg) translateZ(" + myOptions.radius + "px) rotateX(180deg)";
                sides[i].classList.remove("hide");
            } else {
                sides[i].classList.add("hide");
            }
        });
    }
    mySideCount.onFinishChange(sideCountChange);
    sideCountChange(myOptions.sideCount);
    
    function radiusChange(newRadius) {
        sideCountChange(myOptions.sideCount);
    }
    myRadius.onFinishChange(radiusChange);
    radiusChange(myOptions.radius);
    
    function heightChange(newHeight) {
        prism.style.height = newHeight + "px";
        prism.style.top = "calc(50% - " + newHeight / 2 + "px)"
        rectangleCountChange(myOptions.rectangleCount);
    }
    myHeight.onFinishChange(heightChange);
    heightChange(myOptions.height);
    
    // f2 listeners 
    function rectangleCountChange(newCount) {
        [].forEach.call(rectangleArray, function(side, i) {
            [].forEach.call(side, function(rect, i) {
                if(i < myOptions.rectangleCount) {
                    rect.style.height = (myOptions.height - myOptions.vertMargin) / newCount - myOptions.vertMargin + "px";
                    rect.classList.remove("hide");
                } else {
                    rect.classList.add("hide");
                }
            });
        });
    }
    myRectangleCount.onFinishChange(rectangleCountChange);
    rectangleCountChange(myOptions.rectangleCount);
    
    function rectangleWidthChange(newWidth) {
        [].forEach.call(rectangleArray, function(side, i) {
            [].forEach.call(side, function(rect, i) {
                rect.style.width = newWidth + "%";
            });
        });
    }
    myRectangleWidth.onFinishChange(rectangleWidthChange);
    rectangleWidthChange(myOptions.rectangleWidth);
    
    function vertMarginChange(newMargin) {
        [].forEach.call(rectangleArray, function(side, i) {
            [].forEach.call(side, function(rect, i) {
                rect.style.margin = newMargin + "px auto";
            });
        });
        rectangleCountChange(myOptions.rectangleCount);
    }
    myVertMargin.onFinishChange(vertMarginChange);
    vertMarginChange(myOptions.vertMargin);
    
    function borderWidthChange(newWidth) {
        [].forEach.call(rectangleArray, function(side, i) {
            [].forEach.call(side, function(rect, i) {
                rect.style.borderWidth = newWidth + "px";
            });
        });
    }
    myBorderWidth.onFinishChange(borderWidthChange);
    borderWidthChange(myOptions.borderWidthChange);
    
    // f3 listeners
    function colorChange(value) {
        if(!myOptions.rainbowMode)
            [].forEach.call(sides, function(elem, i) {
                sides[i].style.color = "hsl(" + value + ", 55%, " + (20 + (i / myOptions.sideCount) * 40) + "%)";
            });
    }
    myColor.onFinishChange(colorChange);
    colorChange(myOptions.color);
    
    mySolidBG.onFinishChange(function(value) {
        if(value === true)
            prism.classList.add("solid");
        else
            prism.classList.remove("solid");
    });
    
    function goRainbowMode(value) {
        [].forEach.call(sides, function(elem, i) {
            if(value === true)
                sides[i].style.color = "hsl(" + 360 * (i / myOptions.sideCount) + ", 80%, 55%)";
            else
                colorChange(myOptions.color);
        });
    }
    myRainbow.onFinishChange(goRainbowMode);
    
    function checkAnimateThroughSpectrum() {
        if(myOptions.animateThroughSpectrum)
            [].forEach.call(sides, function(elem, i) {
                sides[i].style.color = "hsl(" + c + ", 80%, " + (20 + (i / myOptions.sideCount) * 40) + "%)";
            });
        else if(myOptions.rainbowMode)
            goRainbowMode(true);
        else
            colorChange(myOptions.color);
    }
    
    
    
    // The music player listeners
    audioInput.addEventListener('change', function(event) {
        if(event.target.files[0]) {
            // No error checking of file here, could be added
            stream = URL.createObjectURL(event.target.files[0]);
            
            loadSong(stream);
        }
    }, false);
    
    if(listenButton)
        listenButton.addEventListener('click', chooseOneOfMine, false);
    
    playPauseButton.addEventListener('click', togglePlayPause, false);
    
    
    // The music functions
    function setup() {
        // Stop the previous song if there is one
        if(audio)
            togglePlayPause();
        
        audio = new Audio();
        audioctx = new AudioContext();
        analyser = audioctx.createAnalyser();
        analyser.smoothingTimeConstant = 0.75;
        analyser.fftSize = 512;
        
        audio.addEventListener('ended', songEnded, false);
        
        sourceNode = audioctx.createMediaElementSource(audio);
        sourceNode.connect(analyser);
        sourceNode.connect(audioctx.destination);
    }
    
    function loadSong(stream) {
        setup();

        audio.src = stream;

        togglePlayPause();
        document.body.classList.add('loaded');
        update();
    }
    
    function songEnded() {
        document.body.classList.remove('loaded');
        togglePlayPause();
    }
    
    function togglePlayPause() {
        if(paused) {
            document.body.classList.add('loaded');
            audio.play();
            playPauseButton.innerText = "▮▮";
        } else if(!audio.paused && !audio.ended) {
            audio.pause();
            playPauseButton.innerText = "▶";
        }
        
        paused = !paused;
    }
    
    function chooseOneOfMine() {
        var num = Math.round(Math.random() * (myMusic.length - 1)) + 1;
        loadSong(myMusic[num]);
    }

    
    
    // The drawing functions 
    function drawSide(freqSequence, freqPercent) {   
        // Get the number of rectangles based on the freqValue
        drawRectangles(freqSequence, Math.floor(freqPercent * myOptions.rectangleCount / 100))
    }
    
    function drawRectangles(sideNum, numRectanglesShowing) {
        for(var i = 0; i < myOptions.rectangleCount; i++) {
            var cl = rectangleArray[sideNum][i].classList;
            if(i <= numRectanglesShowing) {
                cl.remove("hide");
                cl.remove("faded");
            } else {
                if(!myOptions.fade)
                    cl.add("hide");
                else
                    cl.add("faded");
            }
        }
    }

    var sectionsAveraged = [maxSideNum],
        countSinceLast = [maxSideNum];
    
    function update() {
        var currTime = Date.now();
        
        var freqArray = new Uint8Array(analyser.frequencyBinCount);
        analyser.getByteTimeDomainData(freqArray);

        // Find the average of the values near to each other (grouping)
        var average = 0,
            count = 0,
            numPerSection = 256 / (myOptions.sideCount + 1),
            nextSection = numPerSection;

        for (var i = 0; i < freqArray.length; i++) {
            var v = freqArray[i];
            average += Math.abs(128 - v); // 128 is essentially 0
            count++;
            
            if(i > nextSection) {
                var currentSection = Math.floor(i / numPerSection - 1);
                
                sectionsAveraged[currentSection] += average / count;
                countSinceLast[currentSection]++;
                
                average = 0;
                count = 0;
                nextSection += numPerSection;
            }
        }
        
        // Find the average of the values since the last time checked per section (smoothing)
        if(currTime - lastTime > timeGap) {  
            for (var i = 0; i < myOptions.sideCount; i++) {
                drawSide(i, (sectionsAveraged[i] / countSinceLast[i]), c);
                sectionsAveraged[i] = 0;
                countSinceLast[i] = 0;
            }
            
            lastTime = currTime;
        } 
        
        checkAnimateThroughSpectrum();
            
        c += 0.5;
        requestAnimationFrame(update);
    }
};

scripts

<script src="http://cdnjs.cloudflare.com/ajax/libs/dat-gui/0.5/dat.gui.min.js"></script>

style.css

// All of the commented out things are from the static, pre-dat.gui version that are no longer necessary

//$sideNum: 12;
//$rectNum: 12;

//$width: 100px;
//$margin: 1% * 7.3;
$border: 3px solid #4DA16F; /* Default all same color */


* { box-sizing: border-box; }
html, body { height:100%; }
body { 
    background: rgb(30,30,30);
    font-family: 'Helvatica', sans-serif;
    color: #FFF;
    
    position:relative;
    perspective: 1000px;
    perspective-origin: 50% 50%;
}
.hide { display:none; }
.faded { opacity: 0; }

.prism {
    position:absolute;
    //top:calc(50% - #{$width * 2});
    //left:calc(50% - #{$width * 0.5});
    //width:$width;
    //height:$width * 4;
    transform-style: preserve-3d;
    
    animation:rotate 8s linear infinite;
}

.side {
    width:100%;
    height:100%;
    border-top: $border;
    border-bottom: $border;
    border-color:currentColor;
    
    position:absolute;
}

.rectangle {    
    //height: (100% / $rectNum) - 2%;
    //width:80%;
    //margin:10px auto;
    border: $border;
    border-color:currentColor;
    transition: opacity 150ms;
}

.solid .rectangle {
    background:currentColor;
}

//@for $i from 1 through $sideNum {
//    .side:nth-child(#{$i}) {
//        color: hsl(144, 55%, 20% + ($i / $sideNum) * 40%);
//       
//        transform: rotateY($i * (360 / $sideNum) + deg) translateZ($width * 1.85) rotateX(180deg); 
//    }
//    .side.rainbow:nth-child(#{$i}) {
//        color: hsl(360*($i / $sideNum), 80%, 55%);
//    }
//}

@keyframes rotate {
    from { transform:rotateY(0); }
    to { transform:rotateY(-360deg); }
}



.musicControls, label {
    position: absolute;
    border-radius: 5px;
    border: 1px solid rgba(255, 255, 255, 0.3);
    padding: 10px;
}
.musicControls { 
    top: 20px;
    left: 20px;
}

label {
    left: 20px;
    top: 100px;
    font-style:italic;
}


body.loaded {
    #loading {
      display: none;
    }
}