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var IS_SKV8 = typeof document == "undefined";
var HAS_PATH = typeof Path2D != "undefined";
var HAS_DISPLAY_LIST = typeof DisplayList != "undefined";
var NumTeeth = 24;
var NumGears = 60;
var DeltaTheta = Math.PI/90;
var FaceColors = ["#000099", "#006600", "#990000", "#EEEE00"];
var SideColors = ["#0000FF", "#009900", "#FF0000", "#CCCC00"];
function makeGear(pathLike, r) {
var dT = Math.PI*2/NumTeeth;
var dTq = dT/4;
var outer = r;
var inner = 0.7 * r;
pathLike.moveTo(Math.sin(-2*dTq)*outer, Math.cos(-2*dTq)*outer);
for (var i=0; i<NumTeeth; i+=2) {
pathLike.lineTo(Math.sin(dT*i-dTq)*outer, Math.cos(dT*i-dTq)*outer);
pathLike.lineTo(Math.sin(dT*i+dTq)*inner, Math.cos(dT*i+dTq)*inner);
pathLike.lineTo(Math.sin(dT*(i+1)-dTq)*inner, Math.cos(dT*(i+1)-dTq)*inner);
pathLike.lineTo(Math.sin(dT*(i+1)+dTq)*outer, Math.cos(dT*(i+1)+dTq)*outer);
}
}
function gearPath(r) {
if (HAS_PATH) {
p = new Path2D();
makeGear(p, r)
p.closePath();
return p;
} else {
return null;
}
}
function gearDisplayListStroke(r, color) {
if (HAS_DISPLAY_LIST) {
p = new Path2D();
makeGear(p, r)
p.closePath();
var dl = new DisplayList();
dl.strokeStyle = color;
dl.stroke(p);
dl.finalize()
return dl;
} else {
return null;
}
}
function gearDisplayListFill(r, color) {
if (HAS_DISPLAY_LIST) {
p = new Path2D();
makeGear(p, r)
p.closePath();
var dl = new DisplayList();
dl.fillStyle = color;
dl.fill(p);
dl.finalize()
return dl;
} else {
return null;
}
}
function strokeGear(ctx, gear) {
if (HAS_PATH) {
ctx.stroke(gear.path);
} else {
ctx.beginPath();
makeGear(ctx, gear.r);
ctx.closePath();
ctx.stroke();
}
}
function fillGear(ctx) {
if (HAS_PATH) {
ctx.fill(gear.path);
} else {
ctx.beginPath();
makeGear(ctx, gear.r);
ctx.closePath();
ctx.fill();
}
}
function draw3DGear(ctx, angle, gear) {
ctx.strokeStyle = gear.sideColor;
ctx.fillStyle = gear.faceColor;
ctx.rotate(angle);
strokeGear(ctx, gear);
for (var i=0; i < 20; i++) {
ctx.rotate(-angle);
ctx.translate(0.707, 0.707);
ctx.rotate(angle);
if (HAS_DISPLAY_LIST) {
ctx.draw(gear.gearStroke);
} else {
strokeGear(ctx, gear);
}
}
if (HAS_DISPLAY_LIST) {
ctx.draw(gear.gearFill);
} else {
fillGear(ctx, gear);
}
ctx.rotate(-angle);
}
function draw3DGearAt(ctx, angle, gear) {
ctx.save();
ctx.translate(gear.x, gear.y);
draw3DGear(ctx, angle, gear);
ctx.restore();
}
var onDraw = function() {
var ticks=0;
var rotation = 0;
var gears = [];
for (var i=0; i<NumGears; i++) {
color = Math.floor(Math.random()*FaceColors.length);
r = Math.random()*100+5;
gears.push({
x: Math.random()*500,
y: Math.random()*500,
path: gearPath(r),
gearFill: gearDisplayListFill(r, FaceColors[color]),
gearStroke: gearDisplayListStroke(r, SideColors[color]),
r: r,
faceColor: FaceColors[color],
sideColor: SideColors[color]
});
}
function draw(ctx) {
ctx.resetTransform();
ctx.fillStyle = "#FFFFFF";
ctx.fillRect(0, 0, 499, 499);
rotation += DeltaTheta;
if (rotation >= Math.PI*2) {
rotation = 0;
}
for (var i=0; i < gears.length; i++) {
gear = gears[i];
draw3DGearAt(ctx, rotation, gear);
}
ticks++;
if (IS_SKV8) {
inval();
}
};
function fps() {
console.log(ticks);
ticks = 0;
setTimeout(fps, 1000);
};
setTimeout(fps, 1000);
return draw;
}();
if (!IS_SKV8) {
window.onload = function(){
var canvas = document.getElementById("gears");
var ctx = canvas.getContext("2d");
function drawCallback() {
onDraw(ctx);
setTimeout(drawCallback, 1);
}
setTimeout(drawCallback, 1);
}
}
console.log("HAS_PATH: " + HAS_PATH);
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