X-Git-Url: https://git.ucc.asn.au/?a=blobdiff_plain;f=course%2Fsemester2%2Fpprog%2Fassignment1%2Fnbody.c;fp=course%2Fsemester2%2Fpprog%2Fassignment1%2Fnbody.c;h=d2062e46dc9fe6654b0fd6da1241104339b5e612;hb=8050cacaa489292c82977b3d87971eaf9ca3c39b;hp=077616077531277fa27a41c4bee19091a36fbd94;hpb=1612d2449b7c9e4fa202adac00cda23700df44c7;p=matches%2Fhonours.git

diff --git a/course/semester2/pprog/assignment1/nbody.c b/course/semester2/pprog/assignment1/nbody.c
index 07761607..d2062e46 100644
--- a/course/semester2/pprog/assignment1/nbody.c
+++ b/course/semester2/pprog/assignment1/nbody.c
@@ -4,219 +4,134 @@
  * @purpose N-Body simulator - Definition of simulation functions; single threaded version
  */
 
-#include <math.h>
 #include <stdlib.h>
 #include <stdio.h>
-#include <string.h>
+#include <math.h>
 #include <time.h>
-#include <omp.h>
-#include <GL/gl.h>
-#include <GL/glut.h>
-
-double previousTime, eyeTheta, eyePhi, eyeRho;
-float look[3];
-int windowWidth, windowHeight, upY;
-
-double SCALE = 1;
-
-Particle *body;
-int N;
-int numberOfProcessors=1;
-
+#include <string.h>
 
+#include "nbody.h"
 
-/*
+/**
  * Prints the body on screen
  */
-void PrintBody(int i)
+void Body_Print(Body * a)
 {
-	printf("Body #%d M=%f X=%f Y=%f Z=%f Fx=%f Fy=%f Fz=%f Vx=%f Xy=%f Vz=%f\n", 
-           i, body[i].mass, body[i].X, body[i].Y, body[i].Z, body[i].Fx, 
-           body[i].Fy, body[i].Fz,	body[i].Vx, body[i].Vy, body[i].Vz);
+	printf("Body %p M=%f X=%f Y=%f Z=%f Fx=%f Fy=%f Fz=%f Vx=%f Vy=%f Vz=%f\n", 
+           (void*)a, a->mass, a->x[0], a->x[1], a->x[2], a->F[0], a->F[1], a->F[2], a->v[0], a->v[1], a->v[2]);
 }
 
-/*
+/**
  * Computing forces
  */
-void Force(int a) {
+void Body_Force(Body * a, System * s) 
+{
 	double distance;
 	double con;
 	double gd;
 
-	body[a].Fx = body[a].Fy = body[a].Fz = 0;
-
-	for(int b=0; b<N; ++b)
-		if( b != a ){
-		distance = sqrt(square(body[b].X - body[a].X) + square(body[b].Y
-                                - body[a].Y) + square(body[b].Z - body[a].Z));
-		con = G * body[a].mass * body[b].mass / square(distance);
-		gd = con / distance;
-		body[a].Fx += gd * (body[b].X - body[a].X);
-		body[a].Fy += gd * (body[b].Y - body[a].Y);
-		body[a].Fz += gd * (body[b].Z - body[a].Z);
-		}
+	for (unsigned i = 0; i < DIMENSIONS; ++i)
+		a->F[i] = 0;
+
+	for (unsigned index = 0; index < s->N; ++index)
+	{
+		Body * b = s->body+index;
+		if (b == a)
+			continue;
+		
+		distance = 0.0;
+		for (unsigned i = 0; i < DIMENSIONS; ++i)
+			distance += square(b->x[i] - a->x[i]);
+		distance = sqrt(distance);
+		con = G * a->mass * b->mass / square(distance);
+		gd = con / distance;	
+		for (unsigned i = 0; i < DIMENSIONS; ++i)
+			a->F[i] += gd * (b->x[i] - a->x[i]);
+	}
 }
 
-/*
+/**
  * Compute velocities
  */
-void Velocity(int a) {
-		body[a].Vx += body[a].Fx/body[a].mass * DELTA_T;
-		body[a].Vy += body[a].Fy/body[a].mass * DELTA_T;
-		body[a].Vz += body[a].Fz/body[a].mass * DELTA_T;
+void Body_Velocity(Body * a) 
+{
+	for (unsigned i = 0; i < DIMENSIONS; ++i)
+		a->v[i] += a->F[i] / a->mass * DELTA_T;
 }
 
-/*
+/**
  * Compute positions
  */
-void Position(int a) {
-	body[a].X += body[a].Vx * DELTA_T;
-	body[a].Y += body[a].Vy * DELTA_T;
-	body[a].Z += body[a].Vz * DELTA_T;
+void Body_Position(Body * a) 
+{
+	for (unsigned i = 0; i < DIMENSIONS; ++i)
+		a->x[i] += a->v[i] * DELTA_T;
 }
 
-/*
+/**
  * Main compute function
  */
-void Compute() {
-	clock_t start, finish;
+void System_Compute(System * s) 
+{
+//	clock_t start, finish;
 
-	start = clock();
+//	start = clock();
 
-	for(int a=0; a<N; a++) {
-		Force(a); // compute force
-		Velocity(a);
-		Position(a);
+	for (unsigned i = 0; i < s->N; ++i)
+	{
+		Body_Force(s->body+i, s);
+		Body_Velocity(s->body+i);
+		Body_Position(s->body+i);
 	}
 
-	finish = clock();
-	printf("Performance: %ld clock ticks per computation cycle\n", finish-start);
-
-	//	PrintBody(0);
-//	PrintBody(N-1);
 }
 
-/*
- * This function is called repeatedly by graphics library. You can consider 
- * it as main loop in the program.
- */
-void Animate(void) {
 
-	Compute(); //Compute and update new positions for the time step
-	Display(); // Display needs to be called to redraw the screen
-}
-
-/*
- * This function is to manipulate with the image
- */
-void KeyBoard(unsigned char theKey, int mouseX, int mouseY) {
-	if (theKey == 'x' || theKey == 'X') {
-		free(body);
-		exit(EXIT_SUCCESS);
-	}
-		if (theKey == 'i' || theKey == 'I') {
-			eyePhi -= M_PI / 20;
-		if (eyePhi == 0)
-				eyePhi = 2 * M_PI;
-		} else if (theKey == 'm' || theKey == 'I') {
-			eyePhi += M_PI / 20;
-		} else if (theKey == 'j' || theKey == 'J') {
-			eyeTheta -= M_PI / 20;
-		} else if (theKey == 'k' || theKey == 'K') {
-			eyeTheta += M_PI / 20;
-		} else if (theKey == ',') {
-			eyeRho += 0.5;
-		} else if (theKey == '.' || theKey == 'I') {
-			eyeRho -= 0.5;
-		} else if (theKey == 'w' || theKey == 'W') {
-			look[1] += 0.5;
-		} else if (theKey == 'z' || theKey == 'Z') {
-			look[1] -= 0.5;
-		} else if (theKey == 'a' || theKey == 'A') {
-			look[0] -= 0.5;
-		} else if (theKey == 's' || theKey == 'S') {
-			look[0] += 0.5;
-		} else if (theKey == '+') {
-			SCALE *= 1.1;
-		} else if (theKey == '-') {
-			SCALE *= 0.9;
-		}
-		if (sin(eyePhi) > 0) upY = 1;
-		else upY = 1;
-}
 
-void Reshape(int width, int height) {
-	double displayRatio = 1.0 * width / height;
-	windowWidth = width;
-	windowHeight = height;
-	glMatrixMode(GL_PROJECTION);
-    glLoadIdentity();
-    gluPerspective(VIEW_ANGLE, displayRatio, WORLD_NEAR, WORLD_FAR);
-	glViewport(0, 0, windowWidth, windowHeight);
-}
 
 /*
  * This function reads an input file. You can change it if you choose a 
  * different file format
  */
-void readFile(char *fileName) {
+#define LINE_SIZE BUFSIZ
+void System_Init(System * s, char *fileName) 
+{
 	char line[LINE_SIZE];
-	char *token;
-	FILE *file;
+	char * token;
+	FILE * file;
 
 	file = fopen(fileName, "rt");
-	N = atoi(fgets(line, LINE_SIZE, file));
-	body = (Particle*) calloc((size_t)N, sizeof(Particle));
-
-	puts("----------------------Initial field-------------------------------");
-
-	for (int i=0; i<N; ++i)
-		if(fgets(line, LINE_SIZE, file) != NULL){
-		token = strtok(line, ",; ");
-		body[i].mass = atof(token);
-		token = strtok(NULL, ",; ");
-		body[i].X = atof(token);
-		token = strtok(NULL, ",; ");
-		body[i].Y = atof(token);
-		token = strtok(NULL, ",; ");
-		body[i].Z = atof(token);
-		token = strtok(NULL, ",; ");
-		body[i].Vx = atof(token);
-		token = strtok(NULL, ",; ");
-		body[i].Vy = atof(token);
-		token = strtok(NULL, ",; ");
-		body[i].Vz = atof(token);
-
-		PrintBody(i);
+	s->N = atoi(fgets(line, LINE_SIZE, file));
+	s->body = (Body*) calloc((size_t)s->N, sizeof(Body));
+
+	//printf("----------------------Initial field-------------------------------\n");
+
+	for (unsigned i = 0; i < s->N; ++i)
+	{
+		if (fgets(line, LINE_SIZE, file) != NULL)
+		{
+			Body * a = s->body+i;
+			token = strtok(line, ",; ");
+			a->mass = atof(token);
+			
+			for (unsigned j = 0; j < DIMENSIONS; ++j)
+			{
+				token = strtok(NULL, ",; ");
+				a->x[j] = atof(token);
+			}
+			for (unsigned j = 0; j < DIMENSIONS; ++j)
+			{
+				token = strtok(NULL, ",; ");
+				a->v[j] = atof(token);
+			}
+			//Body_Print(a);
 		}
-	puts("--------------------------------------------------------------");
-	puts("Use:\n X - exit\n I, J, K, M - rotate\n W, Z, A, S - move to view"
-         " point\n ./, - zoom in/out\n +/- - scaled zoom in/out\n");
+	}
 
+	//printf("--------------------------------------------------------------\n");
+	
 	fclose(file);
 }
 
 
-// This is main function. Do not change it.
-int main(int argc, char** argv)
-{
-	glutInit(&argc, argv);
 
-	if (argc < 2) {
-		puts("Please provide the filename, i.e. \'nbody bodiesfield.dat\'");
-	    exit(EXIT_SUCCESS);
-	}
-	if (argc == 2) readFile(argv[1]);
-	if (argc == 3) numberOfProcessors = atoi(argv[2]);
-
-	glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
-	glutInitWindowSize(WIDTH, HEIGHT);
-	glutInitWindowPosition(POSITION_X, POSITION_Y);
-	glutCreateWindow("N-Body Parallel");
-	glutDisplayFunc(Display);
-	glutIdleFunc(Animate);
-	glutKeyboardFunc(KeyBoard);
-	glutReshapeFunc(Reshape);
-	Init();
-	glutMainLoop();
-}