#include	<stdio.h>
#include	<Xm/MainW.h>
#include	<Xm/DrawingA.h>
#include	<Xm/RowColumn.h>
#include	<Xm/PushB.h>
#include	<Xm/CascadeB.h>
#include	<Xm/Scale.h>

#define	Interval	100
#define	WinWidth	600
#define	WinHeight	320
#define	TrendHeight	100
#define	TrendUnit	4
#define	TrendSize	(WinWidth/TrendUnit)
#define	PointSize	13
#define	PointColor	"red"
#define	AxisColor	"white"
#define	GridColor	"grey"
#define	FontName	"*-courier-medium-r-normal--20-*-*"

XtAppContext	app_con;
Widget	app_sh, draw, trend, StartButton, StopButton, StepButton;
Boolean	Running = False;

String	fallback_resources[] = {
	"*FontList:     *-helvetica-bold-r-*-140-75-*",
	"*background:   grey90",
	"*.field.background: black",
	"*.field.foreground: yellow",
	"*.trend.background: NavyBlue",
	"*.command.marginWidth: 0",
	"*.command.marginHeight: 0",
	"*.command.spacing: 0",
	"*.alpha.titleString: alpha",
	"*.alpha.minimum: 2000",
	"*.alpha.maximum: 4000",
	"*.alpha.decimalPoints: 3",
	"*.ivalue.titleString: initial value",
	"*.ivalue.maximum: 1000",
	"*.ivalue.decimalPoints: 3",
	"*.Quit.accelerator: Alt<Key>q",
	"*.Quit.acceleratorText: Alt+Q",
	NULL
};
Display	*dpy = NULL;
GC	gc;
Window	win,TrendWin;
Pixmap pmap;
XFontStruct	*fst;
Pixel	fg, bg, pointPixel, axisPixel, gridPixel;

int	Nit = 0;
double	Alpha = 3.6, A0 = 0.2, An, Am;
XPoint	TrendP[TrendSize+1];
int	TrendPCnt = 0;

#define	WinX(x)	((int)((x)*WinWidth*.9+WinWidth*.05))
#define	WinY(y) (WinHeight-1-(int)((y)*WinWidth*.45+WinWidth*.05))
#define	TrendY(y)	(TrendHeight-1-(int)((y)*TrendHeight))
void setup_draw_info()
{
	int	i;
	XColor	scol, ecol;
	dpy = XtDisplay(app_sh);
	gc = DefaultGC(dpy,0);
	win = XtWindow(draw);
	TrendWin = XtWindow(trend);
	pmap = XCreatePixmap(dpy,win,PointSize,PointSize,DefaultDepth(dpy,0));
	XtVaGetValues(draw,XmNforeground,&fg,XmNbackground,&bg,NULL);
	XAllocNamedColor(dpy,DefaultColormap(dpy,0),PointColor,&scol,&ecol);
	pointPixel = scol.pixel;
	XAllocNamedColor(dpy,DefaultColormap(dpy,0),AxisColor,&scol,&ecol);
	axisPixel = scol.pixel;
	XAllocNamedColor(dpy,DefaultColormap(dpy,0),GridColor,&scol,&ecol);
	gridPixel = scol.pixel;
	fst = XLoadQueryFont(dpy,FontName);
	if (fst) XSetFont(dpy,gc,fst->fid);
	XSetLineAttributes(dpy,gc,2,LineSolid,CapRound,JoinRound);
	for (i = 0; i <= TrendSize; i ++) TrendP[i].x = i * TrendUnit;
}

void one_step() { Am = An; An = (1. - An) * An * Alpha; Nit ++; }

void draw_one_step(a1,a2) double a1, a2;
{
	XPoint	p[3];
	p[0].x = WinX(a1);	p[0].y = WinY(a1);
	p[1].x = p[0].x;	p[1].y = WinY(a2);
	p[2].x = WinX(a2);	p[2].y = p[1].y;
	XDrawLines(dpy,win,gc,p,3,CoordModeOrigin);
}
int	OldPX = -9999, OldPY;
void erase_point()
{
	if (OldPX > -PointSize) XCopyArea(dpy,pmap,win,gc,
		0,0,PointSize,PointSize,OldPX,OldPY);
}
void plot_point()
{
	int	x, y;
	x = WinX(An) - PointSize/2;
	y = WinY(An) - PointSize/2;
	if (x > -PointSize && x < WinWidth
	 && y > -PointSize && y < WinHeight) {
		XCopyArea(dpy,win,pmap,gc,x,y,PointSize,PointSize,0,0);
		XFillArc(dpy,win,gc,x,y,PointSize,PointSize,0,64*360);
		OldPX = x; OldPY = y;
	} else	OldPX = -9999;
}
void redisplay()
{
	int	z, i;
	double	a;
	XPoint	p[2];
	XSetForeground(dpy,gc,gridPixel);
	for (i = 1; i < 11; i ++) {
		z = WinX(i*.1); XDrawLine(dpy,win,gc,z,0,z,WinHeight-1);
		z = WinY(i*.1); XDrawLine(dpy,win,gc,0,z,WinWidth-1,z);
	}
	XDrawLine(dpy,win,gc,WinX(-.1),WinY(-.1),WinX(1.1),WinY(1.1));
	for (a = -.1; a <= 1.1; a += 0.05) {
		p[0] = p[1];
		p[1].x = WinX(a);
		p[1].y = WinY((1. - a) * a * Alpha);
		if (a > -1.) XDrawLines(dpy,win,gc,p,2,CoordModeOrigin);
	}
	XSetForeground(dpy,gc,axisPixel);
	z = WinY(0); XDrawLine(dpy,win,gc,0,z,WinWidth-1,z);
	z = WinX(0); XDrawLine(dpy,win,gc,z,0,z,WinHeight-1);
	XSetForeground(dpy,gc,fg);
	i = Nit; Nit = 0; An = Am = A0;
	while (Nit < i-1) { one_step(); draw_one_step(Am,An); }
	XSetForeground(dpy,gc,pointPixel);
	if (i > Nit) { one_step(); draw_one_step(Am,An); }
	plot_point();
}
void reset()
{
	XClearWindow(dpy,win);
	XClearWindow(dpy,TrendWin);
	Nit = 0;
	An = Am = A0;
	TrendPCnt = 0;
	TrendP[0].y = TrendY(A0);
	redisplay();
}
void work_one_step(cl,id)
XtPointer	cl;
XtIntervalId	*id;
{
	int	ndp;
	erase_point();
	if (Am != An) { XSetForeground(dpy,gc,fg); draw_one_step(Am,An); }
	XSetForeground(dpy,gc,pointPixel);
	one_step();
	plot_point();
	draw_one_step(Am,An);
	if (TrendPCnt >= TrendSize) {
		int	i;
		for (i = 0; i < TrendSize; i ++) TrendP[i].y = TrendP[i+1].y;
		XCopyArea(dpy,TrendWin,TrendWin,gc,TrendUnit,0,
			WinWidth-TrendUnit,TrendHeight,0,0);
		XClearArea(dpy,TrendWin,WinWidth-TrendUnit,0,
			TrendUnit,TrendHeight,False);
		ndp = 3;
	} else { TrendPCnt ++; ndp = 2; }
	TrendP[TrendPCnt].y = TrendY(An);
	XSetForeground(dpy,gc,axisPixel);
	XDrawLines(dpy,TrendWin,gc,TrendP+TrendPCnt-ndp+1,ndp,
		CoordModeOrigin);
	if (Running) XtAppAddTimeOut(app_con,Interval,work_one_step,NULL);
}
void RedrawCB(w,cl,cd) Widget w; XtPointer cl,cd;
{
	 XmDrawingAreaCallbackStruct *d = (XmDrawingAreaCallbackStruct *)cd;
	 XExposeEvent	*e = &(d->event->xexpose);
	 redisplay();
}
void ResetCB(w,cl,cd) Widget w; XtPointer cl,cd; { reset(); }
void QuitCB(w,cl,cd) Widget w; XtPointer cl,cd; { exit(0);}
void StartCB(w,cl,cd) Widget w; XtPointer cl,cd;
{
	Running = True;
	XtAppAddTimeOut(app_con,Interval,work_one_step,NULL);
	XtVaSetValues(StartButton,XmNsensitive,False,NULL);
	XtVaSetValues(StopButton,XmNsensitive,True,NULL);
	XtVaSetValues(StepButton,XmNsensitive,False,NULL);
}
void StopCB(w,cl,cd) Widget w; XtPointer cl,cd;
{
	Running = False;
	XtVaSetValues(StopButton,XmNsensitive,False,NULL);
	XtVaSetValues(StartButton,XmNsensitive,True,NULL);
	XtVaSetValues(StepButton,XmNsensitive,True,NULL);
}
void StepCB(w,cl,cd) Widget w; XtPointer cl,cd;
{
	Running = False;
	XtAppAddTimeOut(app_con,4,work_one_step,NULL);
}
void ValueCB(w,cl,cd) Widget w; XtPointer cl,cd;
{
	XmScaleCallbackStruct	*cs = (XmScaleCallbackStruct *)cd;
	*((double *)cl) = cs->value * 0.001;
	reset();
}
void RedrawTrendCB(w,cl,cd) Widget w; XtPointer cl,cd;
{
	if (TrendPCnt <= 0) return;
	XSetForeground(dpy,gc,axisPixel);
	XDrawLines(dpy,TrendWin,gc,TrendP,TrendPCnt+1,CoordModeOrigin);
}
main(argc,argv)
int	argc;
char	*argv[];
{
	Widget	main_win, menu_bar, menu, button, command, scale;
	Arg	args[8];
	int	n;
	app_sh = XtAppInitialize(&app_con,"Logistic map",NULL,0,
		&argc,argv,fallback_resources,NULL,0);
	XtSetArg(args[0],XmNshowSeparator,True);
	XtManageChild(main_win=XmCreateMainWindow(app_sh,"main",args,1));
	XtManageChild(menu_bar=XmCreateMenuBar(main_win,"bar",NULL,0));
	menu = XmCreatePulldownMenu(menu_bar,"FileMenu",NULL,0);
	XtManageChild(button=XmCreatePushButton(menu,"Reset",NULL,0));
	XtAddCallback(button,XmNactivateCallback,ResetCB,NULL);
	XtManageChild(button=XmCreatePushButton(menu,"Quit",NULL,0));
	XtAddCallback(button,XmNactivateCallback,QuitCB,NULL);
	XtSetArg(args[0],XmNsubMenuId,menu);
	XtManageChild(XmCreateCascadeButton(menu_bar,"File",args,1));
	StepButton = XmCreateCascadeButton(menu_bar,"Step",NULL,0);
	XtManageChild(StepButton);
	XtAddCallback(StepButton,XmNactivateCallback,StepCB,NULL);
	StartButton = XmCreateCascadeButton(menu_bar,"Start",NULL,0);
	XtManageChild(StartButton);
	XtAddCallback(StartButton,XmNactivateCallback,StartCB,NULL);
	XtSetArg(args[0],XmNsensitive,False);
	StopButton = XmCreateCascadeButton(menu_bar,"Stop",args,1);
	XtManageChild(StopButton);
	XtAddCallback(StopButton,XmNactivateCallback,StopCB,NULL);
	XtSetArg(args[0],XmNorientation,XmVERTICAL);
	XtManageChild(command=XmCreateRowColumn(main_win,"command",args,1));
	XtSetArg(args[0],XmNorientation,XmHORIZONTAL);
	XtSetArg(args[1],XmNshowValue,True);
	XtSetArg(args[2],XmNvalue,(int)(Alpha*1000));
	XtManageChild(scale=XmCreateScale(command,"alpha",args,3));
	XtAddCallback(scale,XmNvalueChangedCallback,
		ValueCB,(XtPointer)(&Alpha));
	XtSetArg(args[2],XmNvalue,(int)(A0*1000));
	XtManageChild(scale=XmCreateScale(command,"ivalue",args,3));
	XtAddCallback(scale,XmNvalueChangedCallback,
		ValueCB,(XtPointer)(&A0));
	XtSetArg(args[0],XmNwidth,WinWidth);
	XtSetArg(args[1],XmNheight,WinHeight);
	XtManageChild(draw=XmCreateDrawingArea(main_win,"field",args,2));
	XtSetArg(args[1],XmNheight,TrendHeight);
	XtManageChild(trend=XmCreateDrawingArea(main_win,"trend",args,2));
/*	XtVaSetValues(main_win,XmNcommandWindow,command,
		XmNmessageWindow,trend,XmNworkWindow,draw,NULL);
*/	XtVaSetValues(main_win,XmNcommandWindow,draw,
		XmNworkWindow,trend,
		XmNmessageWindow,command,NULL);
	XtRealizeWidget(app_sh);
	setup_draw_info(draw);
	reset();
	XtAddCallback(draw,XmNexposeCallback,RedrawCB,NULL);
	XtAddCallback(trend,XmNexposeCallback,RedrawTrendCB,NULL);
	XtAppMainLoop(app_con);
}