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HTML

              
                <script src="https://cdnjs.cloudflare.com/ajax/libs/dat-gui/0.5/dat.gui.min.js" type="text/javascript"></script>
Starscape
by <a href='https://mightyuhu.github.io/'> Benedikt W.</a>
<br/><br/> Inspired by <a href="https://www.youtube.com/watch?v=-WR0o7NWUy8">Monstercat</a>

<canvas height="500" width="1000" id="canvas"></canvas>
              
            
!

CSS

              
                @import url(https://fonts.googleapis.com/css?family=Open+Sans|Maven+Pro:500);
 A, A:link, A:visited, A:active {
    text-decoration:none;
    color:#b00b00;
    // http://lazy.ly/Iv0#mRN=)
}
body {
    font-family:'Open Sans';
    background: #000;
    min-height: 100%;
    font-size:10px;
    font-family:'Open Sans';
    background-attachment: fixed;
    color: white;
    font-size:10/1px;
    font-family:monospace;
}
canvas {
    margin-top:100px;
    display:block;
    margin: 0 auto;
}
              
            
!

JS

              
                window.requestAnimFrame = (function () {
    return window.requestAnimationFrame || window.webkitRequestAnimationFrame || window.mozRequestAnimationFrame || function (callback) {
        window.setTimeout(callback, 1000 / 60);
    };
})();


$(document).ready(function () {
    $('#canvas').mousedown(function () {
        settings.velocity_x += 2;

    }).mouseup(function () {
        settings.velocity_x -= 2;

    });
    star = function () {
        this.offset = 0;
        this.x = 0,
        this.y = 0,
        this.params = {
            velocity_x: 1,
            velocity_y: 1,
            opacicty: 1,
            lifetime: 3,
            x_offset: 0,
            y_offset: 0,
            radius: 0,
            decay: 0,
            growth: 0,
            amplitude: 100,
            phaseshift: 360,
            freq: 0.05,
            color: '255,255,255'
        };
    };


    star.prototype.init = function () {
        //Randomize
        this.params.phaseshift = (Math.random() * 0.01);
        this.params.amplitude = Math.ceil(Math.random() * settings.amplitudeSeed);
        this.params.freq = (Math.random() * settings.freqSeed);
        this.params.x_offset = Math.ceil(Math.random() * 1000);
        this.params.y_offset = settings.y_center + Math.ceil(Math.random() * settings.y_offsetSeed);
        this.params.lifetime = Math.ceil(Math.random() * 3);
        this.params.velocity_x = (Math.random() * settings.velocity_xSeed)
        this.params.velocity_y = (Math.random() * settings.velocity_ySeed)
        this.params.radius = (Math.random() * settings.maxradius);
        this.params.opacity = Math.round(Math.random() * settings.opacSeed, 2) / 100;
        if (settings.decay) {
            this.params.decay = Math.round(Math.random() * 1.5) * Math.random() * 0.01;
        }
        if (settings.growth) {
            this.params.growth = Math.round(Math.random() * 1.2) * Math.random() * 0.01;
        }

        if (settings.irregColors) {
            switch (Math.ceil(Math.random() * settings.colorPct)) {
                case 1:
                    this.params.color = '255,0,0';
                    break;
                case 2:
                    this.params.color = '0,255,255';
                    break;
                case 3:
                    this.params.color = '0,255,200';
                    break;
                case 4:
                    this.params.color = '255,0,255';
                    break;
                default:
                    this.params.color = '255,255,255';
                    break;
            }
        }
        this.x = this.params.x_offset;
    }

    star.prototype.draw = function (ctx, new_x) {
        this.offset = (this.offset + 1);
        var t = (this.params.x_offset + this.offset);

        if (this.params.opacity > settings.opacMax) {
            this.params.decay *= -1;
            this.params.lifetime--;
        } else if (this.params.opacity <= settings.opacMin) {
            this.params.lifetime--;
            this.params.decay *= -1;
            this.params.opacity = 0;
        }
        if (this.params.radius > settings.maxradius) {
            this.params.growth *= -1;

        } else if (this.params.radius <= 0.2) {
            this.params.growth *= -1;
            this.params.radius = 0.2;
        }
        this.params.radius += 2 * (this.params.growth);

        this.params.opacity += 2 * (this.params.decay);

        this.y = this.params.y_offset + (this.params.amplitude / 4 * Math.sin((2 + t * settings.velocity_y * 0.03) * this.params.freq)) * this.params.velocity_y * settings.scale_y
        this.x += (1 * this.params.velocity_x * settings.velocity_x);
        ctx.beginPath();
        ctx.fillStyle = "rgba(" + this.params.color + "," + Math.round(this.params.opacity * 100) / 100 + ")";
        ctx.arc(this.x, this.y, this.params.radius, 0, Math.PI * 2, false);
        ctx.fill();
    }


    settings = {
        velocity_x: 1,
        scale_y: 1,
        y_center: 250,
        y_offsetSeed: 0,
        velocity_y: 1,
        particles: 1100,
        maxradius: 7,
        irregColors: true,
        decay: true,
        growth: true,
        freqSeed: 1.4,
        amplitudeSeed: 200,
        velocity_xSeed: 3,
        velocity_ySeed: 3,
        opacMax: 0.601,
        opacMin: 0.01,
        opacSeed: 90,
        colorPct: 10


    };

    var stars = [];
    init = function () {
        for (i = 0; i < settings.particles; i++) {
            stars[i] = new star();
            stars[i].init();
        }
    };

    var gui = new dat.GUI();
    gui.add(settings, 'velocity_x', -10.1, 10.1);
    gui.add(settings, 'velocity_y', 0.0, 10.111);
    gui.add(settings, 'scale_y', -10.1, 10.1);
    gui.add(settings, 'y_offsetSeed', 0, 500).onChange(function (value) {
        init();
    })
    gui.add(settings, 'y_center', 0, 500).onChange(function (value) {
        init();
    })
    gui.add(settings, 'maxradius', 0.2, 100.1).onChange(function (value) {
        init();
    });
    gui.add(settings, 'decay').onChange(function (value) {
        init();
    });
    gui.add(settings, 'colorPct', 4, 100).onChange(function (value) {
        init();
    });
    gui.add(settings, 'growth').onChange(function (value) {
        init();
    });
    gui.add(settings, 'irregColors').onChange(function (value) {
        init();
    });
    gui.add(settings, 'particles', 1, 9000).onChange(function (value) {
        init();
    })
    gui.add(settings, 'freqSeed', 0.1, 30.1).onChange(function (value) {
        init();
    });
    gui.add(settings, 'amplitudeSeed', 1, 500).onChange(function (value) {
        init();
    });
    gui.add(settings, 'velocity_xSeed', 1, 10).onChange(function (value) {
        init();
    });
    gui.add(settings, 'velocity_ySeed', 1, 10).onChange(function (value) {
        init();
    });
    gui.add(settings, 'opacMax', 0.01, 1.00).onChange(function (value) {
        init();
    });
    gui.add(settings, 'opacMin', 0.01, 1.00).onChange(function (value) {
        init();
    });
    gui.add(settings, 'opacSeed', 1, 100).onChange(function (value) {
        init();
    });

    gui.open();

    var deg2rad = function (angle) {
        return angle * .017453292519943295; // (angle / 180) * Math.PI;
    }

    var colorfreq = function (i) {
        var frequency = .3;
        i = i % 32;
        var red = Math.ceil(Math.sin(frequency * i + 0) * 127 + 128);
        var green = Math.ceil(Math.sin(frequency * i + 2) * 127 + 128);
        var blue = Math.ceil(Math.sin(frequency * i + 4) * 127 + 128);
        return "rgba(" + red + "," + green + "," + blue + "," + settings.alpha + ")";
    }

    init();
    var ctx = document.getElementById("canvas").getContext('2d');
    var offset = 0;
    (function animloop() {
        requestAnimFrame(animloop);
        ctx.fillStyle = "rgba(0,0,0,1)";
        ctx.fillRect(0, 0, 1000, 1000);
        for (i = 0; i < settings.particles; i++) {
            stars[i].draw(ctx);
            ctx.beginPath();
            ctx.fill();
            if (stars[i].x > 998 || (stars[i].params.lifetime < 0 && stars[i].params.opacity <= 0) || (stars[i].y < (0 - settings.maxradius)) || (stars[i].x < (0 - settings.maxradius)) || (stars[i].y > (500 + settings.maxradius))) {
                stars[i] = new star();
                stars[i].init();
                stars[i].params.x_offset = (-1) * offset;
                stars[i].x -= Math.random() * 200;
                stars[i].params.opacity = 0;
            }
        }
    })();
});
              
            
!
999px

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