You can use the TweenJS MotionGuidePlugin to tween along a path instead of having multiple tweens.
createjs.MotionGuidePlugin.install();
createjs.Tween.get(bar).to({
guide: {path: [10,10, 10,10,400,10, 400,10,400,400, 400,400,10,400, 10,400,10,10]}
}, 6000, createjs.linear);
The path array is basically the set of coordinates for a moveTo call followed by multiple curveTo calls. The coordinates will be interpolated along the path resulting from those calls.
A more modular way to to specify your path array would be to have a function generating it using a set of points you declared.
function getMotionPathFromPoints (points) {
var i, motionPath;
for (i = 0, motionPath = []; i < points.length; ++i) {
if (i === 0) {
motionPath.push(points[i].x, points[i].y);
} else {
motionPath.push(points[i - 1].x, points[i - 1].y, points[i].x, points[i].y);
}
}
return motionPath;
}
var points = [
new createjs.Point(10, 10),
new createjs.Point(400, 10),
new createjs.Point(400, 400),
new createjs.Point(10, 400),
new createjs.Point(10, 10)
];
createjs.MotionGuidePlugin.install();
createjs.Tween.get(bar).to({
guide: {path: getMotionPathFromPoints(points)}
}, 6000, createjs.linear);