JavaScript

语言：

JaveScriptBabelCoffeeScript

确定

window.requestAnimFrame = (function() {

return window.requestAnimationFrame ||

window.webkitRequestAnimationFrame ||

window.mozRequestAnimationFrame ||

window.oRequestAnimationFrame ||

window.msRequestAnimationFrame ||

function(callback) {

window.setTimeout(callback, 1000 / 60);

};

})();

var scol = 'hsla(75, 5%, 95%, 1)';

function ready() {

var c = document.getElementById("canvas");

var $ = c.getContext("2d");

var w = c.width = window.innerWidth;

var h = c.height = window.innerHeight;

var graph = new Graph(c.width, c.height);

window.addEventListener('mousemove', function(e) {

graph.ms.x = e.pageX;

graph.ms.y = e.pageY;

}, false);

window.addEventListener('touchmove', function(e) {

graph.ms.x = e.touches[0].pageX;

graph.ms.y = e.touches[0].pageY;

}, false);

var draw = function() {

graph.figure();

graph.draw($);

};

run();

function run() {

window.requestAnimFrame(run);

draw();

}

}

function Graph(w, h) {

var spiro = this;

spiro.msdn = false;

spiro.ms = {

x: w / 2,

y: h / 2

};

var contC = 224;

var oc = contC / 12 + (contC * 10 / 12 * Math.random()) | 0;

var ic = oc / 12 + (oc * 10 / 12 * Math.random()) | 0;

var rat = contC / oc;

var cont = new Circle(w / 2, h / 2, contC, 0);

cont.strokeStyle = "hsla(75, 5%, 95%, 1)";

var outer = cont.i_circle(oc, 0);

var inner = outer.i_circle(ic, 0);

var loc = [];

var ang = 0;

var bAng = cont.ang;

spiro.figure = function() {

ang += 2.0;

var cAng = ang * Math.PI / 180 - bAng;

cont.set(cAng);

var oAng = -cAng * rat;

outer.set(oAng);

var p = inner.getPos();

loc.push(p);

};

spiro.draw = function($) {

$.clearRect(0, 0, w, h);

$.fillStyle = 'hsla(255,255%,2555%,1)';

$.shadowColor = 'hsla(0,0%,0%,.5)';

$.shaodwBlur = 10;

$.shadowOffsetX = 2;

$.shadowOffsetY = 2;

var ms = spiro.ms;

if (cont.graph(ms.x, ms.y)) {

$.lineWidth = 4.0;

cont.draw($);

outer.draw($);

inner.draw($);

}

$.strokeStyle = scol;

$.lineWidth = 2;

$.beginPath();

$.moveTo(loc[0].x, loc[0].y);

for (var i = 1; i < loc.length; i++) {

$.lineTo(loc[i].x, loc[i].y);

}

$.stroke();

};

}

function Circle(cx, cy, r, ang) {

var spiro = this;

spiro.parent = null;

spiro.children = null;

spiro.cx = cx;

spiro.cy = cy;

spiro.r = r;

spiro.strokeStyle = null;

spiro.fillStyle = 'hsla(255,255%,255%,.7)';

spiro.set = function(a) {

spiro.ang = a;

spiro.cos = Math.cos(spiro.ang);

spiro.sin = Math.sin(spiro.ang);

};

spiro.set(ang);

spiro.i_circle = function(ri, ai) {

var x = spiro.cos * (spiro.r - ri);

var y = spiro.sin * (spiro.r - ri);

var ci = new Circle(x, y, ri, ai);

spiro.appendChild(ci);

return ci;

};

spiro.appendChild = function(e) {

if (spiro.children === null) {

spiro.children = [];

}

e.parent = spiro;

spiro.children.push(e);

};

spiro.remove = function(e) {

var kids = spiro.children;

if (kids !== null) {

for (var i in kids) {

if (kids[i] == e) {

kids.splice(i, 1);

}

}

}

};

spiro.getPos = function() {

var x = spiro.cx;

var y = spiro.cy;

var e = spiro.parent;

while (e !== null) {

var xx = e.cx + e.cos * x - e.sin * y;

y = e.cy + e.sin * x + e.cos * y;

x = xx;

e = e.parent;

}

return {

x: x,

y: y

};

};

spiro.graph = function(x, y) {

var p = spiro.getPos();

return (p.x - x) * (p.x - x) + (p.y - y) * (p.y - y) <= spiro.r * spiro.r;

};

spiro.draw = function($) {

if (spiro.strokeStyle === null && spiro.fillStyle === null) {

return;

}

var p = spiro.getPos();

$.beginPath();

$.arc(p.x, p.y, spiro.r, 0, Math.PI * 2.0, true);

if (spiro.strokeStyle !== null) {

$.strokeStyle = spiro.strokeStyle;

$.stroke();

} else {

$.fillStyle = spiro.fillStyle;

$.fill();

}

};

}

ready();

document.getElementById('reset').onclick = ready;

window.addEventListener('resize', function() {

c.width = w = window.innerWidth;

c.height = h = window.innerHeight;

}, false);