JavaScript

语言：

JaveScriptBabelCoffeeScript

确定

var config = {

color: 'blue',

distribution: 'circle'

};

var colorOptions = {

blue: {

bg: "rgb(0, 20, 20)",

fg: "rgba(22, 33, 220, 0.05)"

},

fire: {

bg: "rgb(20, 0, 0)",

fg: "rgba(255, 120, 0, 0.04)"

},

gold: {

bg: "rgb(0, 20, 20)",

fg: "rgba(80, 60, 60, 0.06)"

},

green: {

bg: "rgb(0, 20, 0)",

fg: "rgba(16, 88, 33, 0.06)"

},

purple: {

bg: "rgb(7, 7, 20)",

fg: "rgba(50, 50, 150, 0.02)"

},

mono: {

bg: "rgb(0, 0, 0)",

fg: "rgba(255, 255, 255, 0.008)"

}

};

function sandline(ctx, p1, p2) {

var samples = 35;

for (var i = 0; i < samples; i++) {

var location = Math.random();

var x = lerp(p1.x, p2.x, location);

var y = lerp(p1.y, p2.y, location);

ctx.fillRect(x, y, 1, 1);

}

}

function lerp(a, b, f) {

return a + f * (b - a);

}

function Point(x, y) {

this.pos = Vector(x, y);

this.lastpos = Vector(x, y);

this.origin = Vector(x, y);

this.velocity = Vector((0.5 - Math.random()) * 0.8, (0.5 - Math.random()) * 0.8);

this.acceleration = Vector();

}

Point.prototype.updatePos = function() {

this.pos.add(this.velocity);

this.velocity.add(this.acceleration);

};

var ctx = fullscreenCanvas().ctx;

var canvas = ctx.canvas;

function Randomwalk(x, y, color) {

this.person = new Point(x, y);

this.friend = new Point(x + (0.5 - Math.random()) * 10, y + (0.5 - Math.random()) * 10);

this.color = color;

this.life = 0;

}

function gravity(pos1, pos2, G) {

var diff = Vector(pos1).subtract(pos2);

var norm = Math.sqrt(100.0 + diff.lengthSq());

var mag = G / (norm * norm * norm);

return diff.scale(G / Math.pow(norm, 3));

}

Randomwalk.prototype.update = function() {

this.person.velocity.x += (0.5 - Math.random()) * 0.1;

this.person.velocity.y += (0.5 - Math.random()) * 0.1;

this.friend.velocity.x += (0.5 - Math.random()) * 0.1;

this.friend.velocity.y += (0.5 - Math.random()) * 0.1;

var dx = this.person.velocity.x - this.friend.velocity.x;

var dy = this.person.velocity.y - this.friend.velocity.y;

this.person.velocity.x += dx * 0.05;

this.person.velocity.y += dy * 0.05;

this.friend.velocity.x += dx * 0.05;

this.friend.velocity.y += dy * 0.05;

var d = gravity(this.person.pos, this.friend.pos, 8);

this.person.velocity.subtract(d);

this.friend.velocity.add(d);

var d1 = gravity(this.person.pos, this.person.origin, 3);

this.person.velocity.subtract(d1);

var d2 = gravity(this.friend.pos, this.friend.origin, 3);

this.friend.velocity.subtract(d2);

this.person.updatePos();

this.friend.updatePos();

this.life += 1;

};

Randomwalk.prototype.draw = function(ctx) {

var originalAlpha = Spectra(this.color).alpha();

ctx.fillStyle = Spectra(this.color).alpha(originalAlpha - this.life / 43500).rgbaString();

sandline(ctx, this.person.pos, this.friend.pos);

};

var rs = [];

// different distributions

function init() {

rs = [];

ctx.clearRect(0, 0, canvas.width, canvas.height);

ctx.fillStyle = colorOptions[config.color].bg;

ctx.globalCompositeOperation = "lighter";

ctx.fillRect(0, 0, canvas.width, canvas.height);

ctx.fillStyle = colorOptions[config.color].fg;

if (config.distribution === "grid") {

var amountPerRow = 8;

var dx = canvas.width / amountPerRow;

var dy = canvas.height / amountPerRow;

for (var i = 0; i < amountPerRow; i++) {

for (var j = 0; j < amountPerRow; j++) {

var amount = Math.ceil(Math.random() * 6);

for (var k = 0; k < amount; k++) {

rs.push(new Randomwalk(

dx * i + dx / 2,

dy * j + dy / 2,

colorOptions[config.color].fg

));

}

}

}

} else if (config.distribution === "random") {

for (var i = 0; i < 500; i++) {

rs.push(new Randomwalk(Math.random() * ctx.canvas.width, Math.random() * ctx.canvas.height, colorOptions[config.color].fg));

}

} else if (config.distribution === "circle") {

var r = canvas.width / 7;

for (var i = 0; i < 2 * Math.PI; i += 0.04) {

var x = Math.cos(i) * r;

var y = Math.sin(i) * r;

rs.push(new Randomwalk(x + canvas.width / 2, y + canvas.height / 2, colorOptions[config.color].fg));

}

} else if (config.distribution === "anima") {

var r = 155;

for (var i = 0; i < 2 * Math.PI; i += 0.04) {

var x = Math.cos(i) * r;

var y = Math.sin(i) * r;

rs.push(new Randomwalk(x + canvas.width / 2, y + canvas.height / 2, colorOptions['blue'].fg));

}

for (var i = 0; i < 2 * Math.PI; i += 0.06) {

var x = Math.cos(i) * r;

var y = Math.sin(i) * r;

rs.push(new Randomwalk(x + canvas.width / 2, y + canvas.height / 2, colorOptions['fire'].fg));

}

for (var i = 0; i < 2 * Math.PI; i += 0.06) {

var x = Math.cos(i) * r;

var y = Math.sin(i) * r;

rs.push(new Randomwalk(x + canvas.width / 2, y + canvas.height / 2, colorOptions['green'].fg));

}

} else if (config.distribution === "heart") {

for (var t = 0; t < 300; t++) {

x = 16 * Math.pow(Math.sin(t), 3);

y = 100 - (13 * Math.cos(t) - 5 * Math.cos(2 * t) - 2 * Math.cos(3 * t) - Math.cos(4 * t));

x *= 12;

y *= 12;

rs.push(new Randomwalk(x + canvas.width / 2, y - 800, colorOptions[config.color].fg));

}

} else if (config.distribution = 'point') {

for (var i = 0; i < 75; i++) {

rs.push(new Randomwalk(canvas.width / 2, canvas.height / 2, colorOptions[config.color].fg));

}

}

}

init();

// options

// {

// color: ['orange', 'blue', 'gold', 'green', 'purple', 'mono'],

// distribution: ['random', 'grid', 'heart', 'circle', 'anima']

// }

var toggle = renderLoop(function() {

rs.forEach(function(r) {

r.update();

r.draw(ctx);

});

});

config.init = init;

config['pause/unpause'] = function freeze() {

toggle();

};

var gui = new dat.GUI();

gui.add(config, 'color', ['fire', 'blue', 'gold', 'green', 'purple', 'mono']);

gui.add(config, 'distribution', ['random', 'grid', 'heart', 'circle', 'anima', 'point']);

gui.add(config, 'init');

gui.add(config, 'pause/unpause');

config['.'] = 'Right click on image to save';

gui.add(config, '.');