audio-vis/js/sphere.js

let sphereData = [];
Math.HALF_PI = Math.PI / 2;
Math.TWO_PI = Math.PI * 2;

let sphereObject = {
    rotationRaw: [0, 0, 0], // degrees
    rotation: [0, 0, 0], //radians
    rotateInc: [0.0, 0.0, 0.0], //degreesInc
    rotateByBeat: true,
    translate: [0, 0, 0],
    total: 50,
    radius: 500,
    color: {r: 0, g: 0, b: 0},
    colorByBeat: true,
    drawMode: 5,
    sphereMode: 0,
    lightPos: [0, 0, 0],
    pointSize: 2,
    steps: 512,
    dirtyMode: false,
    light: 0.3
}

function readDataBar() {
    let items = sphereObject.steps;
    let dataArray = new Uint8Array(items);
    analyser.getByteFrequencyData(dataArray);
    let arr = [];
    let sum = 0;
    for (let i = 0; i < items; i++) {
        let data = dataArray[i] / 255;
        arr.push(data * .5);
        sum += dataArray[i];
    }
    return [arr, (sum / items) / 255];
}

let sphereDataVectors = [], lastTotal = 0;

// avoid garbage collection each run
function prepareData() {
    let total = sphereObject.total;
    if (lastTotal !== total) {
        sphereDataVectors = [];
        for (let i = 0; i <= total; i++) {
            sphereDataVectors[i] = [];
            for (let j = 0; j <= total; j++) {
                sphereDataVectors[i][j] = new VTVector();
            }
        }
        lastTotal = total;
    }
}

function setupSphere() {
    sphereData = [];
    let data = readDataBar(),
        radData = data[0],
        map = VTUtils.map,
        total = sphereObject.total,
        cTotal = (total + 1) * (total + 1),
        radius = sphereObject.radius,
        rx = radius / c.width,
        ry = radius / c.height,
        counter = 0;

    prepareData();
    for (let i = 0; i <= total; i++) {
        let lat = map(i, 0, total, 0, Math.PI, false);
        for (let j = 0; j <= total; j++) {
            let lon = map(j, 0, total, 0, Math.TWO_PI, false);
            let rAdd = getAddRad(counter, radData, cTotal);
            let realRX = rx + rAdd;
            let realRY = ry + rAdd;
            let {x, y, z} = sphereMode(lat, lon, i, counter, realRX, realRY);
            if (sphereObject.drawMode < 2 || sphereObject.dirtyMode) {
                sphereData.push(x, y, z);
            } else {
                sphereDataVectors[i][j].setXYZ(x, y, z);
            }
            counter++;
        }
    }
    if (sphereObject.drawMode > 1 && !sphereObject.dirtyMode) {
        for (let i = 0; i < total; i++) {
            for (let j = 0; j <= total; j++) {
                let cur = sphereDataVectors[i][j];
                sphereData.push(cur.x, cur.y, cur.z);
                cur = sphereDataVectors[i + 1][j];
                sphereData.push(cur.x, cur.y, cur.z);
            }
        }
    }
    return [VTUtils.peakRGB(data[1] * 2), data[1]];
}

function getAddRad(counter, data, total) {
    let mapping, rAdd, map = VTUtils.map;
    let h = total / 2;
    if (sphereObject.sphereMode === 3) {
        if (counter > h) {
            mapping = map(counter, h, total, data.length - 1, 0);
        } else {
            mapping = map(counter, 0, h, 0, data.length - 1);
        }
        rAdd = data[Math.round(mapping)] || 0;
    } else if (sphereObject.sphereMode === 4) {
        if (counter > h) {
            mapping = map(counter, h, total, 0, data.length - 1);
        } else {
            mapping = map(counter, 0, h, data.length - 1, 0);
        }
        rAdd = data[Math.round(mapping)] || 0;
    } else {
        mapping = map(counter, 0, total, 0, data.length - 1);
        rAdd = data[Math.round(mapping)] || 0;
    }
    return rAdd;
}

let position, color, rotate, light, lightPos;

function prepare(program) {
    position = gl.getAttribLocation(program, "a_position");
    color = gl.getUniformLocation(program, "u_color");
    light = gl.getUniformLocation(program, "u_light");
    rotate = gl.getUniformLocation(program, "u_matrix");
    lightPos = gl.getUniformLocation(program, "u_lightPos");
    let pointSize = gl.getUniformLocation(program, "u_pointSize");
    gl.uniform3fv(light, [sphereObject.light, 0, 0]);
    gl.uniform3fv(lightPos, sphereObject.lightPos);
    gl.uniform1f(pointSize, sphereObject.pointSize);
}

function draw() {
    c.width = window.innerWidth;
    c.height = window.innerHeight;
    let aspect = c.height / c.width;
    let d = setupSphere();
    let newColor = d[0];
    let program = shaderHandler.getProgram("sphere");
    gl.useProgram(program);
    prepare(program);
    let matrix = [
        1 / aspect, 0, 0, 0,
        0, 1, 0, 0,
        0, 0, 1, 0,
        sphereObject.translate[0], sphereObject.translate[1], sphereObject.translate[2], 1
    ]
    matrix = TDUtils.multiply(matrix, TDUtils.xRotation(sphereObject.rotation[0]));
    matrix = TDUtils.multiply(matrix, TDUtils.yRotation(sphereObject.rotation[1]));
    matrix = TDUtils.multiply(matrix, TDUtils.zRotation(sphereObject.rotation[2]));
    gl.uniformMatrix4fv(rotate, false, matrix);
    let positionBuffer = gl.createBuffer();
    gl.bindBuffer(gl.ARRAY_BUFFER, positionBuffer);
    gl.bufferData(gl.ARRAY_BUFFER, new Float32Array(sphereData), gl.DYNAMIC_DRAW);
    let vao = gl.createVertexArray();
    gl.bindVertexArray(vao);
    gl.enableVertexAttribArray(position);
    gl.vertexAttribPointer(position, 3, gl.FLOAT, true, 0, 0);
    gl.clearColor(0, 0, 0, 1);
    gl.enable(gl.DEPTH_TEST);
    gl.depthFunc(gl.LEQUAL);
    gl.clearDepth(2.0)
    gl.clear(gl.COLOR_BUFFER_BIT | gl.DEPTH_BUFFER_BIT);
    gl.viewport(0, 0, gl.canvas.width, gl.canvas.height);
    if (sphereObject.colorByBeat) {
        gl.uniform4f(color, newColor.r, newColor.g, 0, 1);
    } else {
        let cx = sphereObject.color;
        gl.uniform4f(color, cx.r, cx.g, cx.b, 1);
    }
    gl.drawArrays(sphereObject.drawMode || gl.POINTS, 0, sphereData.length / 3);
    if (sphereObject.rotateByBeat) {
        sphereObject.rotationRaw[1] += d[1];
        sphereObject.rotationRaw[0] += newColor.r;
    } else {
        for (let i = 0; i < 3; i++) {
            sphereObject.rotationRaw[i] += sphereObject.rotateInc[i];
        }
    }

    for (let i = 0; i < 3; i++) {
        sphereObject.rotation[i] = TDUtils.degToRad(sphereObject.rotationRaw[i])
    }
    requestAnimationFrame(draw);
}

function sphereMode(lat, lon, i, counter, rx, ry) {
    let x, y, z,
        sin = Math.sin,
        cos = Math.cos;
    switch (sphereObject.sphereMode) {
        case 1:
            x = rx * sin(lon) * cos(lat);
            y = ry * sin(lon) * sin(lat);
            z = ry * cos(lat);
            break;
        case 2:
            x = rx * sin(lat) * cos(lat);
            y = ry * sin(lat) * sin(lat);
            z = ry * cos(lon);
            break;
        default:
            x = rx * sin(lat) * cos(lon);
            y = ry * sin(lat) * sin(lon);
            z = ry * cos(lat);
            break;
    }
    return {x: x, y: y, z: z};
}