torus2.c

无线通信的各种运动模型。适用于移动通信、无线传感器网络等领域。 包括：Random walk、random waypoint、random direction、boundless simulation

/******************************************************************************
*   File Name: torus2.c
*   Purpose: an implementation of the boundless simulation area as described
             by Haas et al.
*   Author: Jeff Boleng
*   Date Created:
*
*   Edited 12 July 2006 by Jon Petty:  
*   Changed seed code to rand((int)time(NULL) + (int)getpid())
*
*   Copyright (C) 2004  Toilers Research Group -- Colorado School of Mines
*
*   Please see COPYRIGHT.TXT and LICENSE.TXT for copyright and license
*   details.
******************************************************************************/

#include <stdlib.h>
#include <stdio.h>
#include <time.h>
#include <math.h>
#include <unistd.h>

#define true  1
#define false 0
#define min(a,b)  (((a) < (b)) ? (a) : (b))
#define max(a,b)  (((a) > (b)) ? (a) : (b))

double randAcceleration(double maxA, double t)
{
	double v = 0.0;
	v = ((double)rand()/(double)RAND_MAX)*(maxA * t);
	if (rand()>=(RAND_MAX/2))
	{
		v = -v;
	}
	return v;
}

double randDirection(double maxTheta, double t)
{
	double theta = 0.0;
	theta = ((double)rand()/(double)RAND_MAX)*(maxTheta * t);
	if (rand()>=(RAND_MAX/2))
	{
		theta = -theta;
	}
	return theta;
}

int main(int argc, char *argv[])
{
	double pi = 2*asin(1.0);
	double maxX=0.0, maxY=0.0;
	double endTime=0.0;
	double speedMax=0.0;
	double accelerationMax=0.0;
	double angularChangeMax=0.0;
	double speed = 0.0;
	double direction = 0.0;
	double xLoc = 0.0;
	double yLoc = 0.0;
	double xOld = 0.0;
	double yOld = 0.0;
	double interval;
	double curtime = 0.0;
	int wrap = false;

	if (argc == 8)
	{
		maxX             = atof(argv[1]);
		maxY             = atof(argv[2]);
		endTime          = atof(argv[3]);
		speedMax         = atof(argv[4]);
		accelerationMax  = atof(argv[5]);
		angularChangeMax = (atof(argv[6])/180.0) * pi;
		interval         = atof(argv[7]);

		fprintf(stdout, "#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n");
		fprintf(stdout, "#\tmaxX               = %9.2f\n", maxX);
		fprintf(stdout, "#\tmaxY               = %9.2f\n", maxY);
		fprintf(stdout, "#\tendTime            = %9.2f\n", endTime);
		fprintf(stdout, "#\tspeedMax           = %9.2f\n", speedMax);
		fprintf(stdout, "#\taccelerationMax    = %9.2f\n", accelerationMax);
		fprintf(stdout, "#\tangularChangeMax   = %9.2f\n", angularChangeMax);
		fprintf(stdout, "#\tinterval           = %9.2f\n", interval);
		fprintf(stdout, "#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~\n\n");
	} else {
		fprintf(stdout, "Usage:  torus2 <max-x> <max-y> <end time>\n");
		fprintf(stdout, "               <max. speed> <max. acceleration>\n");
		fprintf(stdout, "               <max. angular change (in degrees)>\n");
		fprintf(stdout, "               <interval>\n");
		return -1;
	}

	srand((int)time(NULL) + (int)getpid());

	speed = min(max((speed+randAcceleration(accelerationMax, interval)), 0.0), speedMax);
	direction = direction + randDirection(angularChangeMax,interval);
	xLoc = ((double)rand()/(double)RAND_MAX)*maxX;
	yLoc = ((double)rand()/(double)RAND_MAX)*maxY;
	xLoc = 500.0;
	yLoc = 500.0;

	fprintf(stdout, "set xrange[0:%f]\n", maxX);
	fprintf(stdout, "set yrange[0:%f]\n\n", maxY);
	fprintf(stdout, "set multiplot\n");
	fprintf(stdout, "plot \'-\' notitle with linespoints\n");
	fprintf(stdout, "%f  %f\ne\n", xLoc, yLoc);
	fprintf(stdout, "plot \'-\' notitle with lines\n");
	fprintf(stdout, "%f  %f\n", xLoc, yLoc);

	while (curtime <= endTime)
	{
		speed = min(max((speed+randAcceleration(accelerationMax, interval)), 0.0), speedMax);
		direction = direction + randDirection(angularChangeMax,interval);
		xOld = xLoc;
		yOld = yLoc;
		xLoc += speed*cos(direction);
		yLoc += speed*sin(direction);
		fprintf(stdout, "%f  %f\n", xLoc, yLoc);
		if (xLoc >= maxX)
		{
			xLoc = 0.0;
			wrap = true;
		} else if (xLoc <= 0.0) {
			xLoc = maxX;
			wrap = true;
		}
		if (yLoc >= maxY)
		{
			yLoc = 0.0;
			wrap = true;
		} else if (yLoc <= 0.0) {
			yLoc = maxY;
			wrap = true;
		}
		if (wrap)
		{
			wrap = false;
			/* plot the place the path wraps */
			fprintf(stdout, "%f  %f\n", xOld, yOld);
			fprintf(stdout, "e\n");
			/* plot the wrapping exit point in another color */
			fprintf(stdout, "plot \'-\' notitle with linespoints 8\n");
			fprintf(stdout, "%f  %f\n", xOld, yOld);
			fprintf(stdout, "e\n");
			/* plot the wrapping entry point in another color */
			fprintf(stdout, "plot \'-\' notitle with linespoints 18\n");
			fprintf(stdout, "%f  %f\n", xLoc, yLoc);
			fprintf(stdout, "e\n");
			fprintf(stdout, "plot \'-\' notitle with lines\n");
			fprintf(stdout, "%f  %f\n", xLoc, yLoc);
		}
		curtime += interval;
	} /* while (curtime <= endTime) */

	fprintf(stdout, "e\n\n");
	fprintf(stdout, "plot \'-\' notitle with linespoints\n");
	fprintf(stdout, "%f  %f\ne\n", xLoc, yLoc);
	fprintf(stdout, "set nomultiplot\n");

	return 0;
}