ShaneBrumback/threejs-examples-interactive-audio-driven-particle-systems.html

## threejs-examples-interactive-audio-driven-particle-systems.html
<!DOCTYPE html>
<html>
<head>
    <meta charset="utf-8">
    <title>Blog - Interactive Audio Driven Particle Systems | www.ShaneBrumback.com</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">

    <!--Social Sharing-->
    <link rel="stylesheet" href="/css/app.css?2">

    <!--Font resources-->
    <script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
    <script src="https://use.fontawesome.com/releases/v5.15.4/js/all.js" data-mutate-approach="sync"></script>
    <link href="https://fonts.googleapis.com/css2?family=Bebas+Neue&display=swap" rel="stylesheet">

</head>
<body>

    <center>
        <button id="startButton"><i class="fas fa-play"></i> Play Audio</button>
        <button id="stopButton" style="display: none;"><i class="fas fa-stop"></i> Stop Audio</button>
        <div id="divRange"></div>
        <div id="divRange"></div>
        <div id="divRangeFooter"></div>
    </center>


    <script src="https://cdn.jsdelivr.net/npm/three@latest/build/three.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/three@latest/examples/js/controls/OrbitControls.js"></script>


    <script type="module">

        // Declare global variables
        let camera, scene, renderer, particles, controls, analyser, sound;

        const particleCount = 10000;
        const areaSize = 10;

        // Function to initialize the scene and setup initial configurations
        function init() {
            // Create a scene
            scene = new THREE.Scene();

            // Create a camera with perspective projection
            camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000);
            camera.position.x = 2;
            camera.position.y = 2;
            camera.position.z = 2;

            // Set up the WebGL renderer with antialiasing and alpha
            renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true });
            renderer.setPixelRatio(window.devicePixelRatio);
            renderer.setSize(window.innerWidth, window.innerHeight);
            renderer.toneMapping = THREE.ReinhardToneMapping;
            renderer.shadowMap.enabled = true;
            renderer.shadowMap.type = THREE.PCFSoftShadowMap;
            renderer.domElement.id = 'renderer';
            renderer.setClearColor(0x000000, 1); // Set background color to black
            renderer.domElement.style.position = 'fixed';
            renderer.domElement.style.zIndex = '-1';
            renderer.domElement.style.left = '0';
            renderer.domElement.style.top = '0';
            document.body.appendChild(renderer.domElement);

            // Create a grid to visualize the area size
            const gridHelper = new THREE.GridHelper(areaSize, areaSize);
            scene.add(gridHelper);

            // Create particles as a group and add them to the scene
            particles = new THREE.Group();
            for (let i = 0; i < particleCount; i++) {
                const particle = new THREE.Mesh(
                    new THREE.BoxGeometry(0.05, 0.05, 0.05),
                    new THREE.MeshBasicMaterial({ color: 0x0000ff })
                );
                particle.position.set(
                    Math.random() * areaSize - areaSize / 2,
                    0,
                    Math.random() * areaSize - areaSize / 2
                );
                particles.add(particle);
            }
            scene.add(particles);

            // Create OrbitControls to enable camera movement
            controls = new THREE.OrbitControls(camera, renderer.domElement);
            // Set autoRotate for the controls to true for auto-rotation
            controls.autoRotate = true;

            // Add a new property to store the original y position for each particle
            particles.children.forEach((particle) => {
                particle.originalY = particle.position.y;
            });

            // Attach event listener to a button to start audio processing
            var playButton = document.getElementById('startButton');
            playButton.addEventListener('pointerdown', playNow);

            // Attach event listener to handle window resize
            window.addEventListener('resize', onWindowResize);

            // Start the animation loop
            animate();

            // Hide/show buttons on click
            const startBtn = document.getElementById('startButton');
            const stopBtn = document.getElementById('stopButton');

            startBtn.addEventListener('click', () => {
                startBtn.style.display = 'none';
                stopBtn.style.display = 'inline-block';
            });

            stopBtn.addEventListener('click', () => {
                sound.stop();
                stopBtn.style.display = 'none';
                startBtn.style.display = 'inline-block';

            });
        }

        // Animation loop to update the particle movement and render the scene
        function animate() {
            requestAnimationFrame(animate);

            if (sound) {
                // Get frequency data from the analyser
                const frequencyData = analyser.getFrequencyData();

                // Calculate the average frequency
                let totalFrequency = 0;
                for (let i = 0; i < frequencyData.length; i++) {
                    totalFrequency += frequencyData[i];
                }
                const averageFrequency = totalFrequency / frequencyData.length;

                // Map the average frequency to a suitable range for particle movement
                const frequency = mapRange(averageFrequency, 0, 255, 0, 1);

                // Map the frequency to a color range (from blue to bright orange)
                const color = new THREE.Color().setHSL(frequency * 0.17, 1, 0.7); // Adjust the saturation (0.7) for bright orange

                // Move particles up on the y-axis when the frequency changes
                particles.children.forEach((particle) => {
                    const threshold = frequency * Math.floor(Math.random() * 10); // Adjust the multiplier as needed to control the particle movement
                    if (particle.position.x <= threshold && particle.position.z <= threshold) {
                        // Lerp to the new y position (threshold)
                        particle.position.y = lerp(particle.position.y, threshold, 0.1); // Adjust the lerp factor (0.1) for desired speed

                        // Check if the particle has a material and create one if it doesn't
                        if (!particle.material) {
                            particle.material = new THREE.MeshBasicMaterial();
                        }

                        // Set the particle color based on the mapped frequency
                        particle.material.color.copy(color);
                    } else {
                        // Lerp back to the original y position (0)
                        particle.position.y = lerp(particle.position.y, particle.originalY, 0.1); // Adjust the lerp factor (0.1) for desired speed
                        particle.material.color.set(0x0000ff); // Set color to blue
                    }

                    // Check frequency = 0 set color back to blue
                    if (frequency == 0)
                        particle.material.color.set(0x0000ff); // Set color to blue
                });
            }

            controls.update();
            renderer.render(scene, camera);
        }

        // Helper function for linear interpolation
        function lerp(a, b, t) {
            return a + t * (b - a);
        }

        // Helper function to map a value from one range to another
        function mapRange(value, low1, high1, low2, high2) {
            return low2 + ((high2 - low2) * (value - low1)) / (high1 - low1);
        }

        // Event listener for window resize events
        window.addEventListener('resize', function () {
            const width = window.innerWidth;
            const height = window.innerHeight;

            camera.aspect = width / height;
            camera.updateProjectionMatrix();

            renderer.setSize(width, height);
        });

        // Initialize the scene
        init();

        // Function to handle starting the audio processing
        function playNow() {
            if (sound) {
                sound.stop();
            }

            // Create an AudioListener and add it to the camera
            const listener = new THREE.AudioListener();
            camera.add(listener);

            // Create the PositionalAudio object (passing in the listener)
            sound = new THREE.PositionalAudio(listener);

            // Load a sound and set it as the PositionalAudio object's buffer
            const audioLoader = new THREE.AudioLoader();
            audioLoader.load('../sounds/threejs-drum-particles-001.mp3', function (buffer) {
                sound.setBuffer(buffer);
                sound.setLoop(true);
                sound.setRefDistance(100);
                sound.play();
            });

            // Set up the analyser so we can get the audio frequency data
            analyser = new THREE.AudioAnalyser(sound, 128);

            // Add the sound to the particles group
            particles.add(sound);
        }

        // Function to handle window resize events
        function onWindowResize() {
            camera.aspect = window.innerWidth / window.innerHeight;
            camera.updateProjectionMatrix();

            renderer.setSize(window.innerWidth, window.innerHeight);
        }


    </script>
</body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<title>Blog - Interactive Audio Driven Particle Systems \| www.ShaneBrumback.com</title>
	<meta name="viewport" content="width=device-width, initial-scale=1">

	<!--Social Sharing-->
	<link rel="stylesheet" href="/css/app.css?2">

	<!--Font resources-->
	<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>
	<script src="https://use.fontawesome.com/releases/v5.15.4/js/all.js" data-mutate-approach="sync"></script>
	<link href="https://fonts.googleapis.com/css2?family=Bebas+Neue&display=swap" rel="stylesheet">

	</head>
	<body>

	<center>
	<button id="startButton"><i class="fas fa-play"></i> Play Audio</button>
	<button id="stopButton" style="display: none;"><i class="fas fa-stop"></i> Stop Audio</button>
	<div id="divRange"></div>
	<div id="divRange"></div>
	<div id="divRangeFooter"></div>
	</center>


	<script src="https://cdn.jsdelivr.net/npm/three@latest/build/three.min.js"></script>
	<script src="https://cdn.jsdelivr.net/npm/three@latest/examples/js/controls/OrbitControls.js"></script>


	<script type="module">

	// Declare global variables
	let camera, scene, renderer, particles, controls, analyser, sound;

	const particleCount = 10000;
	const areaSize = 10;

	// Function to initialize the scene and setup initial configurations
	function init() {
	// Create a scene
	scene = new THREE.Scene();

	// Create a camera with perspective projection
	camera = new THREE.PerspectiveCamera(75, window.innerWidth / window.innerHeight, 0.1, 1000);
	camera.position.x = 2;
	camera.position.y = 2;
	camera.position.z = 2;

	// Set up the WebGL renderer with antialiasing and alpha
	renderer = new THREE.WebGLRenderer({ antialias: true, alpha: true });
	renderer.setPixelRatio(window.devicePixelRatio);
	renderer.setSize(window.innerWidth, window.innerHeight);
	renderer.toneMapping = THREE.ReinhardToneMapping;
	renderer.shadowMap.enabled = true;
	renderer.shadowMap.type = THREE.PCFSoftShadowMap;
	renderer.domElement.id = 'renderer';
	renderer.setClearColor(0x000000, 1); // Set background color to black
	renderer.domElement.style.position = 'fixed';
	renderer.domElement.style.zIndex = '-1';
	renderer.domElement.style.left = '0';
	renderer.domElement.style.top = '0';
	document.body.appendChild(renderer.domElement);

	// Create a grid to visualize the area size
	const gridHelper = new THREE.GridHelper(areaSize, areaSize);
	scene.add(gridHelper);

	// Create particles as a group and add them to the scene
	particles = new THREE.Group();
	for (let i = 0; i < particleCount; i++) {
	const particle = new THREE.Mesh(
	new THREE.BoxGeometry(0.05, 0.05, 0.05),
	new THREE.MeshBasicMaterial({ color: 0x0000ff })
	);
	particle.position.set(
	Math.random() * areaSize - areaSize / 2,
	0,
	Math.random() * areaSize - areaSize / 2
	);
	particles.add(particle);
	}
	scene.add(particles);

	// Create OrbitControls to enable camera movement
	controls = new THREE.OrbitControls(camera, renderer.domElement);
	// Set autoRotate for the controls to true for auto-rotation
	controls.autoRotate = true;

	// Add a new property to store the original y position for each particle
	particles.children.forEach((particle) => {
	particle.originalY = particle.position.y;
	});

	// Attach event listener to a button to start audio processing
	var playButton = document.getElementById('startButton');
	playButton.addEventListener('pointerdown', playNow);

	// Attach event listener to handle window resize
	window.addEventListener('resize', onWindowResize);

	// Start the animation loop
	animate();

	// Hide/show buttons on click
	const startBtn = document.getElementById('startButton');
	const stopBtn = document.getElementById('stopButton');

	startBtn.addEventListener('click', () => {
	startBtn.style.display = 'none';
	stopBtn.style.display = 'inline-block';
	});

	stopBtn.addEventListener('click', () => {
	sound.stop();
	stopBtn.style.display = 'none';
	startBtn.style.display = 'inline-block';

	});
	}

	// Animation loop to update the particle movement and render the scene
	function animate() {
	requestAnimationFrame(animate);

	if (sound) {
	// Get frequency data from the analyser
	const frequencyData = analyser.getFrequencyData();

	// Calculate the average frequency
	let totalFrequency = 0;
	for (let i = 0; i < frequencyData.length; i++) {
	totalFrequency += frequencyData[i];
	}
	const averageFrequency = totalFrequency / frequencyData.length;

	// Map the average frequency to a suitable range for particle movement
	const frequency = mapRange(averageFrequency, 0, 255, 0, 1);

	// Map the frequency to a color range (from blue to bright orange)
	const color = new THREE.Color().setHSL(frequency * 0.17, 1, 0.7); // Adjust the saturation (0.7) for bright orange

	// Move particles up on the y-axis when the frequency changes
	particles.children.forEach((particle) => {
	const threshold = frequency * Math.floor(Math.random() * 10); // Adjust the multiplier as needed to control the particle movement
	if (particle.position.x <= threshold && particle.position.z <= threshold) {
	// Lerp to the new y position (threshold)
	particle.position.y = lerp(particle.position.y, threshold, 0.1); // Adjust the lerp factor (0.1) for desired speed

	// Check if the particle has a material and create one if it doesn't
	if (!particle.material) {
	particle.material = new THREE.MeshBasicMaterial();
	}

	// Set the particle color based on the mapped frequency
	particle.material.color.copy(color);
	} else {
	// Lerp back to the original y position (0)
	particle.position.y = lerp(particle.position.y, particle.originalY, 0.1); // Adjust the lerp factor (0.1) for desired speed
	particle.material.color.set(0x0000ff); // Set color to blue
	}

	// Check frequency = 0 set color back to blue
	if (frequency == 0)
	particle.material.color.set(0x0000ff); // Set color to blue
	});
	}

	controls.update();
	renderer.render(scene, camera);
	}

	// Helper function for linear interpolation
	function lerp(a, b, t) {
	return a + t * (b - a);
	}

	// Helper function to map a value from one range to another
	function mapRange(value, low1, high1, low2, high2) {
	return low2 + ((high2 - low2) * (value - low1)) / (high1 - low1);
	}

	// Event listener for window resize events
	window.addEventListener('resize', function () {
	const width = window.innerWidth;
	const height = window.innerHeight;

	camera.aspect = width / height;
	camera.updateProjectionMatrix();

	renderer.setSize(width, height);
	});

	// Initialize the scene
	init();

	// Function to handle starting the audio processing
	function playNow() {
	if (sound) {
	sound.stop();
	}

	// Create an AudioListener and add it to the camera
	const listener = new THREE.AudioListener();
	camera.add(listener);

	// Create the PositionalAudio object (passing in the listener)
	sound = new THREE.PositionalAudio(listener);

	// Load a sound and set it as the PositionalAudio object's buffer
	const audioLoader = new THREE.AudioLoader();
	audioLoader.load('../sounds/threejs-drum-particles-001.mp3', function (buffer) {
	sound.setBuffer(buffer);
	sound.setLoop(true);
	sound.setRefDistance(100);
	sound.play();
	});

	// Set up the analyser so we can get the audio frequency data
	analyser = new THREE.AudioAnalyser(sound, 128);

	// Add the sound to the particles group
	particles.add(sound);
	}

	// Function to handle window resize events
	function onWindowResize() {
	camera.aspect = window.innerWidth / window.innerHeight;
	camera.updateProjectionMatrix();

	renderer.setSize(window.innerWidth, window.innerHeight);
	}



	</script>
	</body>
	</html>