// Circle Object
// Dynlayer addon object to move a layer in a circle
// 19990326

// Copyright (C) 1999 Dan Steinman
// Distributed under the terms of the GNU Library General Public License
// Available at http://www.dansteinman.com/dynduo/

function Circle(dynlayer,name) {
	this.dynlayer = dynlayer
	this.name = name
	this.play = CirclePlay
	this.slide = CircleSlide
	this.pause = CirclePause
	this.stop = CircleStop
}
function CirclePlay(radius,angleinc,angle,endangle,speed,fn) {
	if (this.active) return
	if (!this.paused) {
		this.radius = radius
		this.angleinc = angleinc
		this.angle = angle
		this.endangle = endangle
		this.speed = speed
		this.fn = fn
		this.centerX = eval(this.dynlayer+'.x') - this.radius*Math.cos(this.angle*Math.PI/180)
		this.centerY = eval(this.dynlayer+'.y') + this.radius*Math.sin(this.angle*Math.PI/180)
		if (this.endangle!=null) {
			this.angleinc = Math.abs(this.angleinc)
			if (this.endangle<this.angle) this.angleinc *= -1
		}
	}
	this.active = true
	this.paused = false
	eval(this.dynlayer+'.'+this.name+'.slide()')
}
function CircleSlide() {
	if (this.active && (this.endangle==null || Math.abs(this.angleinc)<Math.abs(this.endangle-this.angle))) {
		this.angle += this.angleinc
		var x = this.centerX + this.radius*Math.cos(this.angle*Math.PI/180)
		var y = this.centerY - this.radius*Math.sin(this.angle*Math.PI/180)
		eval(this.dynlayer+'.moveTo('+x+','+y+')')
		setTimeout(this.dynlayer+'.'+this.name+'.slide()',this.speed)
	}
	else {
		if (this.endangle!=null) {
			var x = Math.round(this.centerX + this.radius*Math.cos(this.endangle*Math.PI/180))
			var y = Math.round(this.centerY - this.radius*Math.sin(this.endangle*Math.PI/180))
			eval(this.dynlayer+'.moveTo('+x+','+y+')')
		}
		if (!this.paused) {
			this.active = false
			eval(this.fn)
		}
	}
}
function CirclePause() {
	if (this.active) {
		this.active = false
		this.paused = true
	}
}
function CircleStop() {
	this.active = false
	this.paused = false
}