#include <u.h>#include <libc.h>#include <draw.h> int debug = 0; struct Cal {	double scalex;	double transx;	double scaley;	double transy;} cal; /* Calibrate the pen */ Point pts[5]; Point pens[5]; Point up	= {  0, -10};Point down	= {  0,  10};Point left	= {-10,   0};Point right	= { 10,   0}; Pointpen2scr(Point p){	return Pt(p.x * cal.scalex / 65536.0 + cal.transx,			  p.y * cal.scaley / 65536.0 + cal.transy);} Pointscr2pen(Point p){	return Pt((p.x - cal.transx) * 65536.0 / cal.scalex,			  (p.y + cal.transy) * 65536.0 / cal.scaley);} voidcross(Point p) {	draw(screen, screen->r, display->white, nil, ZP);	line(screen, addpt(p, up), addpt(p, down), Endsquare, Endsquare, 0, display->black, ZP);	line(screen, addpt(p, left), addpt(p, right), Endsquare, Endsquare, 0, display->black, ZP);	flushimage(display, 1);} Pointgetmouse(int mouse) {	static char buf[50];	int x, y, b, n;	Point p; 	n = 0;	p.x = p.y = 0;	do{		if (read(mouse, buf, 48) != 48)			sysfatal("read: %r");		if (debug > 1) fprint(2, "%s\n", buf);		if (buf[0] == 'r') {			b = 1;			continue;		}		if (buf[0] != 'm')			sysfatal("mouse message: %s", buf);		x = strtol(buf+1, nil, 10);		y = strtol(buf+13, nil, 10);		b = strtol(buf+25, nil, 10);		p.x = (n * p.x + x)/(n+1);		p.y = (n * p.y + y)/(n+1);		n++;	}while (b & 0x7);	return p;} voidmain(int argc, char **argv) {	int i, mouse, mousectl, wctl, ntries;	Rectangle r, oldsize; 	ARGBEGIN{	case 'd':		debug = 1;		break;	}ARGEND; 	if((mouse = open("/dev/mouse", OREAD)) < 0	 && (mouse = open("#m/mouse", OREAD)) < 0)		sysfatal("#m/mouse: %r"); 	mousectl = open("#m/mousectl", ORDWR);	if(mousectl < 0)		sysfatal("#m/mousectl: %r"); 	if(initdraw(nil, nil, "calibrate") < 0)		sysfatal("initdraw: %r"); 	wctl = -1;	for(ntries = 0; ntries < 3; ntries++){		r = insetrect(display->image->r, 2); 		if(wctl < 0)			wctl = open("/dev/wctl", ORDWR);		if(wctl >= 0){			char buf[4*12+1]; 			buf[48] = 0;			oldsize = screen->r;			if(fprint(wctl, "resize -r %R", r) <= 0)				sysfatal("write /dev/wctl, %r");			if(getwindow(display, Refbackup) < 0)				sysfatal("getwindow");			if(debug) fprint(2, "resize: %R\n", screen->r); 			if(read(mousectl, buf, 48) != 48)				sysfatal("read mousectl: %r");			if(debug > 1) fprint(2, "mousectl %s\n", buf);			if(buf[0] != 'c')				sysfatal("mousectl message: %s", buf);			cal.scalex = strtol(buf+ 1, nil, 10);			cal.scaley = strtol(buf+13, nil, 10);			cal.transx = strtol(buf+25, nil, 10);			cal.transy = strtol(buf+37, nil, 10);		}else{			fprint(mousectl, "calibrate");			cal.scalex = 1<<16;			cal.scaley = 1<<16;			cal.transx = 0;			cal.transy = 0;		} 		fprint(2, "calibrate %ld %ld %ld %ld (old)\n",			(long)cal.scalex, (long)cal.scaley, (long)cal.transx, (long)cal.transy); 		if(debug)			fprint(2, "screen coords %R\n", screen->r);		pts[0] = addpt(Pt( 16,  16), screen->r.min);		pts[1] = addpt(Pt( 16, -16), Pt(screen->r.min.x, screen->r.max.y));		pts[2] = addpt(Pt(-16,  16), Pt(screen->r.max.x, screen->r.min.y));		pts[3] = addpt(Pt(-16, -16), screen->r.max);		pts[4] = Pt((screen->r.max.x + screen->r.min.x)/2,					(screen->r.max.y + screen->r.min.y)/2);; 		for(i = 0; i < 4; i++){			cross(pts[i]);			pens[i] = scr2pen(getmouse(mouse));			if (debug) fprint(2, "%P\n", pens[i]);		} 		cal.scalex = (pts[2].x + pts[3].x - pts[0].x - pts[1].x) * 65536.0 /				  (pens[2].x + pens[3].x - pens[0].x - pens[1].x);		cal.scaley = (pts[1].y + pts[3].y - pts[0].y - pts[2].y) * 65536.0 /				  (pens[1].y + pens[3].y - pens[0].y - pens[2].y);		cal.transx = pts[0].x - (pens[0].x*cal.scalex) / 65536.0;		cal.transy = pts[0].y - (pens[0].y*cal.scaley) / 65536.0; 		if(debug)			fprint(2, "scale [%f, %f], trans [%f, %f]\n",				cal.scalex, cal.scaley, cal.transx, cal.transy); 		fprint(mousectl, "calibrate %ld %ld %ld %ld",			(long)cal.scalex, (long)cal.scaley, (long)cal.transx, (long)cal.transy); 		cross(pts[4]);		pens[4] = getmouse(mouse); 		draw(screen, screen->r, display->white, nil, ZP);		flushimage(display, 1); 		if(abs(pts[4].x-pens[4].x) <= 4 && abs(pts[4].y-pens[4].y) <= 4){			fprint(2, "Calibration ok: %P -> %P\n", pts[4], pens[4]);			break;		}		fprint(2, "Calibration inaccurate: %P -> %P\n", pts[4], pens[4]);	}	print("calibrate='%ld %ld %ld %ld'\n",		(long)cal.scalex, (long)cal.scaley, (long)cal.transx, (long)cal.transy); 	if(debug)		for(i = 0; i < 4; i++){			cross(pts[i]);			pens[i] = getmouse(mouse);			if (debug) fprint(2, "%P\n", pens[i]);		} 	if(wctl >= 0)		fprint(wctl, "resize -r %R", oldsize); }