//<script>
/* ballnavigation01.js
* June 2002
* Andreas Ipp
* andreas.ipp@gmx.at
* http://strange.itp.tuwien.ac.at/~ipp/
*
* physical balls navigation framework
*/

/* Tested under:
*  Windows XP:
*    - Microsoft Internet Explorer 6.0.26
*    - Netscape Navigator 6.2.3
*    - Netscape Navigator 4.08
*    - Opera 6.03
*    - Mozilla 1.0
*
*  Windows 2000:
*    - Microsoft Internet Explorer
*
*  Linux:
*    - Netscape Communicator 4.77
*    - Mozilla 0.9.9 (very slow with vopacity != 100)
*    - Opera 6.0 Technology Preview 3
*    - Lynx v2.8.4
*
*/

// Global variables:
var OldWinx=0; // Old Window size
var OldWiny=0;

// Globale Variablen / Global variables
var BallMax = 0; // Maximum number of balls
var BallNumber = 0; // Currently visible number of balls
var TestBounce = 1; // Test bouncing
var TestMouse = 1;  // Test mouse interaction
var Damping = 0.999; // General Damping
var GravityConst = 1; // Constant Gravity on
var Gravityx = 0;
var Gravityy = .04;
var GravityCentral = 0; // Central Gravity on
var GravityG = 0;

var MenuForce = 0; // Force to simulate Menu
var MenuTime = 0;	// Timing for Menu
var CollapseMenu = 0; // Collapsed menu?
var MenuX = 3;   // Menu Position identifiers
var MenuY = 30;
var MenuDX = 0;
var MenuDY = 150;
var MenuStallX = 60;
var MenuStallY = 30;
var MenuBoundBottom = 1000;

var TraceMax = 15; // Number of Trace Points
var TraceOn = 0; // Trace On
var TraceBall = 0; // Trace which ball
var TraceLoopMax = BallMax + 2; // Duration of 1 Loop

var Balls = new Array();

var ClipLeft = 0;  // Range of movement
var ClipTop = 0;
var ClipRight = 10;
var ClipBottom = 10;

var SettingMenuState = -1;  //-1 not initialized, 0 closed, 1 open

var Running = 1;

var ResizeAgain = 0;

var startsetting = settingrandom;

// Small Trace Point
function TracePoint(vlaytr) {
	this.vlaytr = vlaytr;
	this.x = 0;
	this.y = 0;
	this.visible = 0;
}

// Neue Klasse Ball / new class ball
function ball(vlayobj, vlayobjtext,vlayobjmenu, tracekind, vlayobjstop) {
	this.vlayobj = vlayobj; // pointer to vlay.objectid
	this.vlayobjtext = vlayobjtext; // text description
	this.vlayobjmenu = vlayobjmenu; // menu
	this.vlayobjstop = vlayobjstop; // stop for inactive
	this.x = 0;  //position
	this.y = 0;
	this.vx = 0;  //velocity
	this.vy = 0;
	this.ax = 0;  //acceleration
	this.ay = 0;
	   
	this.hintstate = 1; // hintstate: 0 off, 1 on
	this.menustate = -1; // menustate: 0 off, 1 on, -1 initialize
	this.stopstate = 0; // no stopping
	   
	this.hasgravityconst = 1;  // exclude some particles from forces
	this.hasgravitycentral = 1;
	   
	this.Trace = new Array(); // Array of Tracepoints
	this.TraceNow = 0; // current active Tracepoint
	   
	for (var i=0; i<TraceMax; i++) {
		this.Trace[i] = new TracePoint(vlay[tracekind+i]);
		// this.Trace[i].vlaytr.vpos(10 * i, 10 * i);
	}
}

function animationinit() {   
	// initialize balls
	BallMax = BallInitMax;
	for (var i=0; i<BallMax; i++) {
		with(BallInit[i]) {
			Balls[i] = new ball(vlay[ballid],vlay[balltextid],vlay[ballmenuid],balltraceid, vlay[ballstopid]);
		}
	}
	
	BallNumber=BallMax;
	TraceLoopMax = BallMax + 2

	startsetting();

	vlay.settingmenu.vopacity(100);
	hide(vlay.settingmenu);
	SettingMenuState = 0;
	closeAllMenus();
	clearalltraces();
}

function stopallballs() {
	for (i=0; i<BallMax; i++) {
		with (Balls[i]) {
		//	x = 200 + 130*i;
		//	y = 200;
			vx = 0;
			vy = 0;
			ax = 0;
			ay = 0;
		}
	}
}

function settingreset() {
	for (i=0; i<BallMax; i++) {
		with (Balls[i]) {
		//	x = 200 + 130*i;
		//	y = 200;
		//	vx = 0;
		//	vy = 0;
		//	ax = 0;
		//	ay = 0;
		//	vlayobj.vpos(x,y);
			hintstate = 1;
			menustate = -1;
			hasgravityconst = 1;
			hasgravitycentral = 1;
			show(vlayobj);
		}
	}
	BallNumber = BallMax;
	
	// BallNumber = 3; // Currently visible number of balls
	TestBounce = 1;
	TestMouse = 1;
	Damping = 0.999; // General Damping
	GravityConst = 0; // Constant Gravity off
	Gravityx = 0;
	Gravityy = 0;
	GravityCentral = 0; // Central Gravity on
	GravityG = 0;
	
	MenuForce = 0;
	MenuTime = 0;
	CollapseMenu = 0;
	MenuX = 3;   // Menu Position identifiers
	MenuY = 30;
	MenuDX = 0;
	MenuDY = 150;
	MenuStallX = 60;
	MenuStallY = 30;
	
//	TraceOn = 0; // Trace On
	TraceBall = 0; // Trace which ball
	TraceLoopMax = BallMax + 2; // Duration of 1 Loop

	vlay.settingmenu.vopacity(100);
	hide(vlay.settingmenu);
	SettingMenuState = 0;
	
	clearalltraces();
	activateAllBalls();
}

function startanimation() {
   Running = 1;
}

function stopanimation() {
   Running = 0;
}

function toggleanimation() {
	if (Running != 0) {
		Running = 0;
	}
	else
	{
		Running = 1;
		//animation();
	}
}

function starttrace() {
	TraceOn = 1;
	showalltraces();
}

function stoptrace() {
	TraceOn = 0;
	clearalltraces();
}

function toggletrace() {
	if (TraceOn != 0) {
		TraceOn = 0;
		clearalltraces();
	}
	else
	{
		TraceOn = 1;
		showalltraces();
	}
}

function animation() {
	getWinSize();
	if (Winx != OldWinx || Winy != OldWiny || ResizeAgain > 0) windowresized();
	ClipLeft = 0;
	ClipTop = 0;
	ClipRight = Winx - 102;
	ClipBottom = Winy - 102;
	   
	if (Running == 1) {
		if (TestMouse == 1) mouseinteraction();
		if (TestBounce == 1) ballbounce();
		forces();
		if (MenuForce == 1) menuforces();
		moveobjects();
			   
		if (TraceOn == 1) showtraces();
		setTimeout("animation()",20);
	}
	else
	{
		// Reduced functionality
		if (TestMouse == 1) mouseinteraction();
		setTimeout("animation()",100);
	}
}

function windowresized() {
	//alert("res");
	// Things we have to do after resizing window
	// Extra for Opera 6.0 Technology Preview 3
	// After change of Window Size or Zoom makes invisible objects visible
	
	// After Resize finished, we refresh 5 times.
	if (Winx != OldWinx || Winy != OldWiny) ResizeAgain = 5; 
	if (ResizeAgain > 0) ResizeAgain--;
	
	if (SettingMenuState == 0) {
		hide(vlay.settingmenu);
		vlay.settingmenu.vpos(0,0);
	}

	for (i=0; i<BallMax; i++) {
		with (Balls[i]) {
			if (hintstate ==0) {
				hide(vlayobjtext);
				vlayobjtext.vpos(0,0);
			}
			if (menustate ==0) {
				hide(vlayobjmenu);
				vlayobjmenu.vpos(0,0);
			}
			show(vlayobj);
			if (stopstate ==0) {
				hide(vlayobjstop);
				vlayobjstop.vpos(0,0);
			}
			else {
				show(vlayobjstop);
			};
		
			// Check if balls are now outside
			if (x + 102 > Winx) x = Winx-102;
			if (y + 102 > Winy) y = Winy-102;
			if (x < 0) x = 0;
			if (y < 0) y = 0;
		}
	}
	BallNumber = BallMax;
	closeAllMenus();
	
	MenuBoundBottom = Winy; //ideally should be Window-Size...
	setmenulayout();

	OldWinx = Winx;
	OldWiny = Winy;
}

function mouseinteraction() {
	// Test for interaction with mouse
	if (SettingMenuState == 1) {
		// Menu open
		// Check if we stay within new menu
		var divsize = new Object();
		getObjSize(vlay.settingmenu,divsize);

		if (mousex < divsize.left-15 || mousex > divsize.right+15 || mousey < divsize.top-15 || mousey > divsize.bottom+15) {
		    vlay.settingmenu.vopacity(100);
			hide(vlay.settingmenu);
			SettingMenuState = 0;
		}
		return;
	
	};
	for (i=0; i<BallNumber; i++){
		with (Balls[i]) {
			dx = mousex - x - 50;
			dy = mousey - y - 50;
			distance = Math.sqrt(dx*dx + dy*dy);
			if (distance < 50 || menustate == 1) {
				if (Running == 1) {
					//damping:
					vx*=.9;
					vy*=.9;
				
					//Sog zur Mitte / drag to center:
					// constant + spring
					var pot = 1 / distance + 0.02;
					ax+=dx * pot;
					ay+=dy * pot;
				};
													
				// Expand Menu if collapsed
				MenuTime = 0;
				
				// Change position of hint:
				if (x<100) {
					// Position right
					vlayobjtext.vpos(x+110,y+20);
				}
				else if (y < Winy/2) {
					// Position below
					vlayobjtext.vpos(x,y+110);
				}
				else
				{
					// Position above
					vlayobjtext.vpos(x,y-50);
				};
				
				//display text
				if (hintstate == 0)
				{
					show(vlayobjtext);
					hintstate = 1;
					if (SettingMenuState != 0)
					{
						vlay.settingmenu.vopacity(100);
						hide(vlay.settingmenu);
						SettingMenuState = 0;
					}
					
					// also, as soon as we touch it, we activate behaviour:
					hasgravityconst = 1;
					hasgravitycentral = 1;
					if (stopstate !=0) {
						stopstate = 0;
						hide(vlayobjstop);
					}
				}

				if (menustate != 0) {
					// Check if we stay within new menu
					var divsize = new Object();
					getObjSize(vlayobjmenu,divsize);

					if (mousex < divsize.left-15 || mousex > divsize.right+15 || mousey < divsize.top-15 || mousey > divsize.bottom+15) {
					    vlayobjmenu.vopacity(100);
						hide(vlayobjmenu);
						menustate = 0;
					}
				}
			}
			else
			{
				if (hintstate != 0)
				{
					hide(vlayobjtext);
					hintstate = 0;
				}
				if (menustate != 0)
				{
					vlayobjmenu.vopacity(100);
					hide(vlayobjmenu);
					menustate = 0;
				}
			}
		}
	}
}

function ballbounce() {
	// 2 balls bounce off each other
	
	for (i=0; i<BallNumber; i++) {
		var b1 = Balls[i];
		for (j=i+1; j<BallNumber; j++) {
			var b2 = Balls[j];
			dx = b2.x - b1.x;
			dy = b2.y - b1.y;
			distance = Math.sqrt(dx*dx + dy*dy);
			if (distance < 100) {
				if (distance > 0) {
					dxu = dx / distance; // unit vectors
					dyu = dy / distance;
					
					//bounce velocities
					pn1 = b1.vx * dxu + b1.vy * dyu; //scalar product
					pn2 = b2.vx * dxu + b2.vy * dyu;
					pnd = pn2-pn1;
					
					//tangential components stay the same, but normal components are exchanged
					b1.vx += +pnd * dxu;
					b1.vy += +pnd * dyu;
					
					b2.vx += -pnd * dxu;
					b2.vy += -pnd * dyu;
					
					// displace the balls
					df = (distance - 100) / 2;
					b1.x += df*dxu;
					b1.y += df*dyu;
					b2.x += -df*dxu;
					b2.y += -df*dyu;
					
					if (GravityCentral && b1.hasgravitycentral && b2.hasgravitycentral) {
						// displacement breaks conservation of energy..
						// balls get faster and faster. 
						// so here we subtract Energy-gain from displacement
						var pncm = (pn1 + pn2)/2; // include m1, m2; center of mass velocity of normal vectors
						var pn1cm = pn1-pncm; // velocity tangential component in center of mass
						var pn2cm = pn2-pncm;						
						
						var E1old = pn1cm * pn1cm; // * m1  // kinetic Energy
						var E2old = pn2cm * pn2cm; // * m2
						
						//var cmvx = (b1.vx + b2.vx)/2; // include m1, m2 for center of mass velocity
						//var cmvy = (b1.vy + b2.vy)/2;
						//var b1cmvx = b1.vx-cmvx; // velocity in center of mass
						//var b1cmvy = b1.vy-cmvy;
						//var b2cmvx = b2.vx-cmvx;
						//var b2cmvy = b2.vy-cmvy;
						
						//var E1old = b1cmvx * b1cmvx + b1cmvy * b1cmvy; // * m1  //kinetic Energy before displacement
						//var E2old = b2cmvx * b2cmvx + b2cmvy * b2cmvy; // * m2
						
						var EnergyGain = -GravityG * ((1/distance)-(1/(distance+2*df))); // * m1 * m2
						
						var E1new = E1old - EnergyGain;
						var E2new = E2old - EnergyGain;
						if (E1new < 0) E1new = 0; // oh, we could have never come here.. mei shir =)
						if (E2new < 0) E2new = 0;
						
						//E1new = 0; E2new = 0;
						if (E1old < 0.00001) E1old = 1;  // to avoid division by zero below
						if (E2old < 0.00001) E2old = 1;
												
						var fact1 = Math.sqrt(E1new / E1old);  // / m1
						var fact2 = Math.sqrt(E2new / E2old);  // / m2
						
						//b1.vx = b1cmvx * fact1 + cmvx;
						//b1.vy = b1cmvy * fact1 + cmvy;
						//b2.vx = b2cmvx * fact2 + cmvx;
						//b2.vy = b2cmvy * fact2 + cmvy;
						
						//alert(b1.vx+","+b1.vy+","+b2.vx+","+b2.vy);
						b1.vx += -(1-fact1) * pn2cm * dxu;  // remember that pn2(cm) and pn1(cm) are already swapped
						b1.vy += -(1-fact1) * pn2cm * dyu;
						b2.vx += -(1-fact2) * pn1cm * dxu;
						b2.vy += -(1-fact2) * pn1cm * dyu;
						//alert(b1.vx+","+b1.vy+","+b2.vx+","+b2.vy);
						
					}
					
					// also, as soon as the balls interact, we activate behaviour:
					b1.hasgravityconst = 1;
					b1.hasgravitycentral = 1;
					if (b1.stopstate !=0) {
						b1.stopstate = 0;
						hide(b1.vlayobjstop);
					}

					b2.hasgravityconst = 1;
					b2.hasgravitycentral = 1;
					if (b2.stopstate !=0) {
						b2.stopstate = 0;
						hide(b2.vlayobjstop);
					}
				}
			}
			else //distance > 100
			{
				// Let's check other forces:
				
				// Central Gravity like between planets
				if (GravityCentral) {
					if (b1.hasgravitycentral && b2.hasgravitycentral) {
						dxu = dx / distance; // unit vectors
						dyu = dy / distance;

						grav = GravityG / (distance * distance)
						b1.ax += grav * dxu;
						b1.ay += grav * dyu;
					
						b2.ax += -grav * dxu;
						b2.ay += -grav * dyu;
					}
				}
			}
		}
	}
}

function forces() {
	
	// Constant Gravity like on Earth
	if (GravityConst) {
		for (i=0; i<BallNumber; i++){
			with (Balls[i]) {
				ax+=Gravityx;
				ay+=Gravityy;
			}
		}
	} // if GravityConst
	
	// PairwiseForces are in ballbounce()

}


// Simulate forces for menu:
function menuforces() {
	var i;
	MenuTime++;
	if (MenuTime > 500)
	{
		// Hide other balls to save resources
		// and set initial velocities
		if (BallNumber > 1) {
			for (i=1; i<BallNumber; i++) {
				hide(Balls[i].vlayobj);
				Balls[i].vy = 5;
				Balls[i].vx = Math.random(4)-2;
			}
			BallNumber = 1;
		}
	}
	else if (MenuTime > 300)
	{
		// CollapseMenu
		CollapseMenu = 1;
		TestBounce = 0;
	}
	else if (MenuTime > 25 && TestBounce == 0)
	{
		// full action
		TestBounce = 1;
		TestMouse = 1;
	}
	else
	{
		if (CollapseMenu == 1) {
			// uncollapse but at first don't listen to mouse
			CollapseMenu = 0;
			TestMouse = 0;
			// show other balls
			for (i=BallNumber; i<BallMax; i++) {
				Balls[i].x=Balls[0].x;
				Balls[i].y=Balls[0].y;
				Balls[i].vlayobj.vpos(Balls[0].x,Balls[0].y);
				show(Balls[i].vlayobj);
			}
			BallNumber = BallMax;
		}
	}

	for (i=0; i<BallNumber; i++) {
		with (Balls[i]) {
			if (CollapseMenu == 0) {
				dx = x - (MenuX + MenuDX * i + ScrollLeft);
				dy = y - (MenuY + MenuDY * i + ScrollTop);
			}
			else
			{
				dx = x - (MenuStallX + ScrollLeft);
				dy = y - (MenuStallY + ScrollTop);
			}
			distance = Math.sqrt(dx*dx + dy*dy);
			if (distance > 0) {
				// like spring
				
				ax += -0.004*dx;
				ay += -0.004*dy; 
			}
			
		}
	}
}

function moveobjects() {
	for (i=0; i<BallNumber; i++){
		with (Balls[i]) {
			vx+=ax;
			vy+=ay;
			vx*=Damping;
			vy*=Damping;
			x+=vx;
			y+=vy;
			ax=0;  //set zero after used
			ay=0;
			
			// Check for borders:
			if (x < ClipLeft) {
				x = 2 * ClipLeft - x;
				vx = Math.abs(vx);
			}
			if (x > ClipRight) {
				x = 2 * ClipRight - x;
				vx = -Math.abs(vx);
			}
			if (y < ClipTop) {
				y = 2 * ClipTop - y;
				vy = Math.abs(vy);
			}
			if (y > ClipBottom) {
				y = 2 * ClipBottom - y;
				vy = -Math.abs(vy);
			}
				
			// Move
			vlayobj.vpos(x,y);
			
		}
	} //for i
}

function showtraces() {
	TraceBall ++;
	if (TraceBall >= TraceLoopMax)
	{
		TraceBall = 0;
	};
	if (TraceBall < BallNumber)
	{
		// Show trace
		with(Balls[TraceBall]) {
			Trace[TraceNow].vlaytr.vpos(x+45,y+45);
			if (Trace[TraceNow].visible == 0)
			{
				show(Trace[TraceNow].vlaytr);
				Trace[TraceNow].visible = 1;
			}
			TraceNow ++;
			if (TraceNow >= TraceMax) TraceNow = 0;
		}
	}
}

function clearalltraces() {
	for (var i=0; i<BallMax; i++) {
		with (Balls[i]) {
			for (var j=0; j<TraceMax; j++) {
				hide(Trace[j].vlaytr);
				Trace[j].vlaytr.vpos(0,0);
				Trace[j].visible = 0;
			}
		}
	}
}

function showalltraces() {
	for (var i=0; i<BallMax; i++) {
		with (Balls[i]) {
			for (var j=0; j<TraceMax; j++) {
				Trace[j].vlaytr.vpos(x+45,y+45);
				show(Trace[j].vlaytr);
				Trace[j].visible = 1;
			}
		}
	}
}

function showballmenu(thisball){
	var menuleft = mousex;
	var menutop = mousey;

	// Check size of new menu
	var divsize = new Object();
	getObjSize(thisball.vlayobjmenu,divsize);
	if (mousex + divsize.right - divsize.left > Winx) menuleft = mousex - (divsize.right-divsize.left);
	if (mousey + divsize.bottom - divsize.top > Winy) menutop = mousey - (divsize.bottom-divsize.top);
	if (mousey + divsize.bottom - divsize.top > ScrollTop + MenuBoundBottom) menutop = mousey - (divsize.bottom - divsize.top);
	if (menutop < ScrollTop) menutop = ScrollTop;
	if (menuleft < 0) menuleft = 0;
	if (menutop < 0) menutop = 0;

	thisball.vlayobjmenu.vpos(menuleft,menutop);
	show(thisball.vlayobjmenu);
	thisball.vlayobjmenu.vopacity(90);
	
	thisball.menustate = 1;
}

function showSettingMenu(){
	var menuleft = mousex;
	var menutop = mousey;
	
	// Check size of new menu
	var divsize = new Object();
	getObjSize(vlay.settingmenu,divsize);
	if (mousex + divsize.right - divsize.left > Winx) menuleft = mousex - (divsize.right-divsize.left);
	if (mousey + divsize.bottom - divsize.top > Winy) menutop = mousey - (divsize.bottom-divsize.top);
	if (mousey + divsize.bottom - divsize.top > ScrollTop + MenuBoundBottom) menutop = mousey - (divsize.bottom - divsize.top);
	if (menutop < ScrollTop) menutop = ScrollTop;
	if (menuleft < 0) menuleft = 0;
	if (menutop < 0) menutop = 0;

	vlay.settingmenu.vpos(menuleft,menutop);
	show(vlay.settingmenu);
	vlay.settingmenu.vopacity(90);
	SettingMenuState = 1;
}

function hideSettingMenu(){
   // set back vopacity to accelerate Mozilla??
   vlay.settingmenu.vopacity(100);
   hide(vlay.settingmenu);
   SettingMenuState = 0;
}

function putBall(i, x, y){
	Balls[i].x=x;
	Balls[i].y=y;
}

function putBallv(i, vx, vy){
	Balls[i].vx=vx;
	Balls[i].vy=vy;
}

// i..startball, inum..# of balls
function putBallChain(i,inum,x1,y1,x2,y2,style){
	var k;
	var dx; var dy;	var sx;	var sy;
	if (inum <= 1){
		Balls[i].x=x1;
		Balls[i].y=y1;
		return;
	}
	switch (style){
	case 1:
		// place equally from (x1,y1) to (x2,y2)
		sx=x1;
		sy=y1;
		dx=(x2-x1)/(inum-1);
		dy=(y2-y1)/(inum-1);
		break;
	case 2:
		// place symetrically around (x1,y1) with distance (x2,y2) between 2 balls
		sx=x1-x2*(inum-1)/2;
		sy=y1-y2*(inum-1)/2;
		dx=x2;
		dy=y2;
		break;
	case 3:
		// place with distance (x2,y2) starting at (x1,y2)
		sx=x1;
		sy=x1;
		dx=x2;
		dy=y2;
	}
	for (k=0;k<inum;k++){
		Balls[i+k].x=sx+dx*k;
		Balls[i+k].y=sy+dy*k;
	}
}

// deactivate Balls with number>=i
function deactivateBalls(i){
	for (var k=i; k<BallNumber; k++) {
		with (Balls[k]) {
			x = 3 + 110 * (k-i);
			y = 3;//110 * (k-i);
			hasgravitycentral = 0;
			stopstate = 1; // Stop
			vlayobjstop.vpos(x,y);
			show(vlayobjstop);
		}
	}
}

function activateAllBalls(){
	for (var i=0; i<BallNumber; i++) {
		with (Balls[i]){
			stopstate = 0;
			hide(vlayobjstop);
		}
	}
}

function rnd(i){
	return Math.floor(Math.random() * i);
}

// Completely random
function settingrandom() {
	var r = rnd(3);
	
	switch(r) {
	case 0:
		settingnoforce();
		break;
	case 1:
		settingnewtonpendulum();
		break;
	case 2:
		settinggravitydown();
		break;
	default:
		settingnoforce();
	}
}

stylenoforce = rnd(2)+1;
function settingnoforce() {
	//var style = rnd(2)+1;
	stylenoforce++;
	if (stylenoforce>2) stylenoforce=1;
		
	settingreset();
	stopallballs();
	
	Damping = 0.995;
	
	getWinSize();
	
	switch (stylenoforce) {
	case 1:
		// all in a chain
		py=Winy/2-50+rnd(30);
		py2=py; //+100*(rnd(3)-1);
		putBallChain(0,BallNumber,50,py,Winx-150,py2,1);
		break;
	case 2:
		// Billard table
		var xb = (Winx-100) * 0.7 + rnd(31)-15;
		var yb = Winy / 2-50+rnd(11)-5;
		//putBallChain(0,BallNumber,50,Winy/2,Winx-50,Win/2,1);
		putBall(0,Winx * .1,yb);
		putBall(1,xb,yb);
		putBall(2,xb+87,yb-50); //sin60°
		putBall(3,xb+87,yb+50);
		putBall(4,xb+174,yb);
		break;
	}
	
}

var stylenewtonpendulum = rnd(3)+1;
function settingnewtonpendulum() {
	stylenewtonpendulum++;
	if (stylenewtonpendulum>3) stylenewtonpendulum=1;
	
	var moveballs = rnd(BallNumber-1)+1;
	var startdir = 2 * rnd(2) - 1;
	settingreset();
	stopallballs();
	
	Damping = 0.9999;
	
	getWinSize();
	switch (stylenewtonpendulum) {
	case 1:
	case 2:
		// horizontally
		px=Winx/2-50;
		py=Winy/2-50 + (Math.random()-.5) * Winy * .4;
		putBallChain(0,BallNumber,px,py,100,0,2);

		for (i=0; i<moveballs; i++){
			Balls[i].vx = -5 * startdir;
		}
		break;
	case 3:
		// hor+vert
		putBall(0,100,220);
		putBall(1,220,100);
		putBall(2,320,100);
		putBall(3,100,320);
		putBall(4,100,420);
		
		Balls[2].vx = 5;
		Balls[4].vy = -5 * ((Winy-100-200) / (Winx-100-100));
		break;
	}
}

stylegravitydown = rnd(4)+1;
function settinggravitydown() {
	stylegravitydown++;
	if (stylegravitydown>4) stylegravitydown=1;
	
	settingreset();
	stopallballs();
	
	GravityConst = 1; // Constant Gravity On
	Gravityx = 0;
	Gravityy = 0.04;
	
	getWinSize();
	px=(Winx-100)/2;
	py=(Winy-100)/2;

	if (stylegravitydown==2 && (BallNumber+1) * 100 > Winy) stylegravitydown=3; // not enough space
	
	switch (stylegravitydown){
	case 1:
		//Random
		putBallChain(0,BallNumber,px-30,py*.2,px+30,py*.2,1);
			
		for (i=0; i<BallNumber; i++) {
			Balls[i].vx = Math.random()*3+(i-BallNumber/2)*2;
			Balls[i].vy = Math.random();
		}
		break;
	case 2:
		// in order vertically
		putBallChain(0,BallNumber,px,py,0,110,2);
		break;
	case 3:
		// in order horizontally
		putBallChain(0,BallNumber,0,0,100,0,3);
		for (i=0; i<BallNumber; i++) {
			Balls[i].vx = i;
		}
		break;
	case 4:
		// horizontally wave
		putBallChain(0,BallNumber,50,50,Winx-150,50,1);
		fd = 1000;
		fv = 32;
		for (i=0; i<BallNumber; i++) {
			Balls[i].y = Balls[i].y + fd * Gravityy / 2 * i*i;
			Balls[i].vy = - fv * Gravityy * i;
		}
		break;
	}
}

function settingsolarsystem() {
	settingreset();
	stopallballs();
	
	GravityCentral = 1;
	GravityG = 5000;
	Damping = .99999;

	getWinSize();

	Balls[0].x = Winx / 2 - 100;
	Balls[0].y = Winy / 2 - 50;
	Balls[1].x = Winx / 2 + 100;
	Balls[1].y = Winy / 2 - 50;
	
	Balls[0].vy = 4;
	Balls[1].vy = -4;
	
	// deactivate other balls
	deactivateBalls(2);
}

var stylethreebody = rnd(2)+1;
function settingthreebody() {
	//var style = rnd(2) + 1;
	stylethreebody++;
	if (stylethreebody>2) stylethreebody=1;
	settingreset();
	stopallballs();
	
	GravityCentral = 1;
	GravityG = 5000;
	Damping = .99999;

	getWinSize();

	switch(stylethreebody) {
	case 1:
		px=Winx/2-50;
		py=Winy/2-50;
		putBall(0,px-250,py-50);
		putBall(1,px+250,py+50);
		putBall(2,px,py);
		vel=2;
		veld=0.1 * (Math.random()-0.5); // small disturbance
		putBallv(0,vel,-vel);
		putBallv(1,vel,-vel+veld);
		putBallv(2,-2*vel,2*vel);
	
		// deactivate other balls
		deactivateBalls(3);
		break;
	case 2:
		px=Winx/2-50;
		py=Winy/2-50;
		r=160;
		b=3;
		vel=3.5+Math.random()*1;
		for (i=0; i<b; i++){
			phi = i*2*Math.PI/b;
			putBall(i,px+r*Math.cos(phi),py+r*Math.sin(phi));
			putBallv(i,-vel*Math.sin(phi),vel*Math.cos(phi))
		}
		//GravityG=0;
		deactivateBalls(b);
		break;
	}
}

// Setting fuer Menu:
function settingmenustyle(mainball) {
	settingreset();
	Damping = .94;
	
	MenuForce = 1;
	MenuCollapse = 0;

	getWinSize();
	setmenulayout();	
	
	if (Balls[0].vx == 0) {
		// not in movement
		putBallChain(0,BallNumber,MenuX+rnd(21)-10,MenuY+rnd(31)-15,MenuDX+rnd(11)-5,MenuDY+rnd(5)-2,3);
	}
}

// after each Window-Resize:
function setmenulayout(){
	MenuStallX = 5;
	MenuStallY = 10;

	MenuX = 10;   // Menu Position identifiers
	MenuY = 30;

	if (Winy > 100 * BallNumber) {
		MenuDX = 0;
		MenuDY = 110;
		MenuBoundBottom = MenuY + BallNumber * MenuDY;
	}
	else {
		MenuDX = (Winx - 150) / (BallNumber-1);
		MenuDY = 0;
	}
//	if (Winy > 100 * BallNumber) {
//		if (100 * BallNumber + MenuY > Winy) MenuY = Winy - 100*BallNumber;
//		MenuDX = 0;
//		MenuDY = (Winy - 2 * MenuY) / (BallNumber);
//	}
//	else {
//		MenuDX = (Winx - 150) / (BallNumber-1);
//		MenuDY = 0;
//	}

}

//</script>