course/semester2/pprog/assignment1/single-thread/graphics.c

   1 /**
   2  * @file graphics.c
   3  * @author Sam Moore (20503628) 2012
   4  *      - Adapted from template program provided by UWA
   5  * @purpose Definition of graphics related functions
   6  * NOTE: This file is identical for both the single-threaded and multi-threaded versions of the program
   7  */
   8
   9
  10 #include <stdlib.h>
  11 #include <stdio.h>
  12 #include <time.h> // Needed for clock
  13 #include <math.h> // Maths functions (sin, cos)
  14
  15 #include "graphics.h" //Function declarations
  16 #include "nbody.h" //The simulation
  17
  18
  19 // --- Variable definitions --- //
  20 double previousTime, eyeTheta, eyePhi, eyeRho;
  21 float look[3];
  22 int windowWidth, windowHeight, upY;
  23 double scale = 1.0;
  24
  25 #ifdef FLYING_CAMERA
  26 Camera eye;
  27 #endif //FLYING_CAMERA
  28
  29 /**
  30  * @function Graphics_Run
  31  * @purpose Setup and start the graphics engine
  32  * @param argc - Number of arguments to main function, passed to glutInit
  33  * @param argv - Argument strings for main function, passed to glutInit
  34  */
  35 void Graphics_Run(int argc, char ** argv)
  36 {
  37         if (options.draw_graphics == false)
  38         {
  39                 // This message is left here for when I inevitably accidentally call the function
  40                 fprintf(stderr, "Graphics_Run should not be called if graphics are disabled!\n");
  41                 exit(EXIT_FAILURE);
  42         }
  43
  44         glutInit(&argc, argv);
  45         glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
  46         glutInitWindowSize(WIDTH, HEIGHT);
  47         glutInitWindowPosition(POSITION_X, POSITION_Y);
  48
  49         //Set window title based on version of program
  50         #ifdef SINGLE_THREADED
  51                 glutCreateWindow("N-Body : Single-Threaded");
  52         #elif defined PTHREADED
  53                 glutCreateWindow("N-Body : Multi-Threaded (pthread)");
  54         #elif defined OMP_THREADED
  55                 glutCreateWindow("N-Body : Multi-Threaded (OpenMP)");
  56         #else
  57                 glutCreateWindow("N-Body");
  58         #endif
  59         glutDisplayFunc(Graphics_Display);
  60         glutIdleFunc(Graphics_Display);
  61         glutKeyboardFunc(Graphics_Keyboard);
  62         glutReshapeFunc(Graphics_Reshape);
  63
  64
  65         glClearColor(1.0,1.0,1.0,0.0);
  66         glColor3f(0.0f, 0.0f, 0.0f);
  67         glPointSize(POINT_SIZE);
  68         glMatrixMode(GL_PROJECTION);
  69         glLoadIdentity();
  70
  71         /*init lighting */
  72
  73         GLfloat mat_specular[] = { 1.0, 1.0, 1.0, 1.0 };
  74         GLfloat mat_shininess[] = { 50.0 };
  75         GLfloat light_position[] = { 1.0, 1.0, 0.0, 0.0 };
  76         glMaterialfv(GL_FRONT, GL_SPECULAR, mat_specular);
  77         glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);
  78         glLightfv(GL_LIGHT0, GL_POSITION, light_position);
  79
  80         glColorMaterial(GL_FRONT,GL_DIFFUSE);                // Set Color Capability
  81
  82         glEnable(GL_LIGHTING);
  83         glEnable(GL_LIGHT0);
  84         glEnable(GL_DEPTH_TEST);
  85
  86         glEnable(GL_COLOR_MATERIAL);                   // Enable color
  87
  88
  89         windowWidth = WIDTH;
  90         windowHeight = HEIGHT;
  91         previousTime = clock();
  92         eyeTheta = 0;
  93         eyePhi = 0.5 * M_PI;
  94         eyeRho = RHO;
  95         upY = 1;
  96         look[0] = 0;
  97         look[1] = 0;
  98         look[2] = 0;
  99         gluPerspective(VIEW_ANGLE, (double)WIDTH/(double)HEIGHT, WORLD_NEAR, WORLD_FAR);
 100
 101         #ifdef FLYING_CAMERA
 102         eye.x[0] = 0; eye.x[1] = 0; eye.x[2] = 1;
 103         eye.y[0] = 0; eye.y[1] = 1; eye.y[2] = 0;
 104         eye.z[0] = 1; eye.z[1] = 0; eye.z[2] = 0;
 105         eye.p[0] = 0; eye.p[1] = 0; eye.p[2] = -50;
 106         #endif //FLYING_CAMERA
 107
 108
 109         //This option must be set, or when glut leaves the main loop. the exit(3) function is called... annoying
 110         glutSetOption(GLUT_ACTION_ON_WINDOW_CLOSE, GLUT_ACTION_CONTINUE_EXECUTION);
 111
 112         glutMainLoop();
 113
 114 }
 115
 116 /**
 117  * @function Graphics_Display
 118  * @purpose This function redraws the screen after the positions of particles
 119  *              have been updated.
 120  *      It also calls System_Compute, and checks for exit conditions, in the single-threaded version only
 121  */
 122 void Graphics_Display()
 123 {
 124
 125         if (options.draw_graphics == false)
 126         {
 127                 // This message is left here for when I inevitably accidentally call the function
 128                 fprintf(stderr, "Graphics_Display should not be called if graphics are disabled!\n");
 129                 exit(EXIT_FAILURE);
 130         }
 131
 132         //Check whether the graphics thread should exit for any reason
 133         if (ExitCondition())
 134         {
 135                 glutLeaveMainLoop();    // original glut does not have this, which makes "nicely" exiting a bit annoying
 136                 return;
 137         }
 138
 139         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 140         glMatrixMode(GL_MODELVIEW);
 141         glLoadIdentity();
 142
 143         #ifdef FLYING_CAMERA
 144
 145         gluLookAt(eye.p[0], eye.p[1], eye.p[2],
 146                 eye.p[0] + eye.x[0], eye.p[1] + eye.x[1], eye.p[2] + eye.x[2],
 147                 eye.z[0], eye.z[1], eye.z[2]);
 148         #else
 149         gluLookAt(eyeRho * sin(eyePhi) * sin(eyeTheta), eyeRho * cos(eyePhi),
 150                 eyeRho * sin(eyePhi) * cos(eyeTheta),look[0], look[1], look[2], 0, upY, 0);
 151         #endif //FLYING_CAMERA
 152
 153         BeforeDraw(); // Stuff to do before graphics is allowed to draw
 154                         // Single-thread - perform a computation step, obviously! It's not done anywhere else
 155                         // Multiple threads - ensure that all body positions are updated (ie: not halfway through step).
 156                         //      (We don't care about the force and velocity variables though)
 157
 158         for (int i = 0; i < universe.N; ++i)
 159         {
 160
 161                 Body * b = universe.body+i;
 162                 glColor3f(0.0f, b->mass/1e11*100, 0.0f);
 163                 //glColor3f(1.0f, 0.0f, 0.0f);
 164                 glPushMatrix(); // to save the current matrix
 165                 glTranslated(scale*b->x[0], scale*b->x[1], scale*b->x[2]);
 166                 glutSolidSphere (BALL_SIZE, 10, 10);
 167                 glPopMatrix(); // restore the previous matrix
 168         }
 169         glFlush();
 170
 171         AfterDraw(); // Stuff to do after graphics is done drawing
 172                         // Single-thread - Nothing at all
 173                         // Multiple threads - signal threads it is safe to change position variables
 174
 175 }
 176
 177 /**
 178  * @function Graphics_Keyboard
 179  * @purpose This function is to manipulate with the image
 180  * @param theKey key pressed
 181  * @param mouseX, mouseY position of the mouse in the window
 182  */
 183 void Graphics_Keyboard(unsigned char theKey, int mouseX, int mouseY)
 184 {
 185         if (theKey == 'x' || theKey == 'X')
 186         {
 187                 QuitProgram(false);
 188                 return;
 189         }
 190
 191         #ifdef FLYING_CAMERA
 192         switch (theKey)
 193         {
 194                 // Translate in direction of camera
 195                 case 'W':
 196                 case 'w':
 197                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 198                                 eye.p[i] += eye.x[i];
 199                         break;
 200                 // Translate backwards from camera direction
 201                 case 'S':
 202                 case 's':
 203                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 204                                 eye.p[i] -= eye.x[i];
 205                         break;
 206                 // Translate left from camera direction
 207                 case 'A':
 208                 case 'a':
 209                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 210                                 eye.p[i] -= eye.y[i];
 211                         break;
 212                 // Translate right from camera direction
 213                 case 'D':
 214                 case 'd':
 215                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 216                                 eye.p[i] += eye.y[i];
 217                         break;
 218                 // Translate up from camera direction
 219                 case 'Q':
 220                 case 'q':
 221                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 222                                 eye.p[i] += eye.z[i];
 223                         break;
 224                 // Translate down from camera direction
 225                 case 'E':
 226                 case 'e':
 227                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 228                                 eye.p[i] -= eye.z[i];
 229                         break;
 230
 231                 // Rotate camera direction "down"
 232                 // (pitch control)
 233                 case 'I':
 234                 case 'i':
 235                 {
 236                         float theta = M_PI/80.0;
 237                         Camera old = eye;
 238
 239                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 240                         {
 241                                 eye.z[i] = old.z[i] * cos(theta) + old.x[i] * sin(theta);
 242                                 eye.x[i] = old.x[i] * cos(theta) - old.z[i] * sin(theta);
 243                         }
 244                         break;
 245                 }
 246                 // Rotate camera direction "up"
 247                 // (pitch control)
 248                 case 'K':
 249                 case 'k':
 250                 {
 251                         float theta = -M_PI/80.0;
 252                         Camera old = eye;
 253
 254                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 255                         {
 256                                 eye.z[i] = old.z[i] * cos(theta) + old.x[i] * sin(theta);
 257                                 eye.x[i] = old.x[i] * cos(theta) - old.z[i] * sin(theta);
 258                         }
 259                         break;
 260                 }
 261                 // Rotate camera direction "left"
 262                 // (yaw control)
 263                 case 'J':
 264                 case 'j':
 265                 {
 266                         float theta = +M_PI/80.0;
 267                         Camera old = eye;
 268
 269                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 270                         {
 271                                 eye.y[i] = old.y[i] * cos(theta) + old.x[i] * sin(theta);
 272                                 eye.x[i] = old.x[i] * cos(theta) - old.y[i] * sin(theta);
 273                         }
 274                         break;
 275                 }
 276                 // Rotate camera direction "right"
 277                 // (yaw control)
 278                 case 'L':
 279                 case 'l':
 280                 {
 281                         float theta = -M_PI/80.0;
 282                         Camera old = eye;
 283
 284                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 285                         {
 286                                 eye.y[i] = old.y[i] * cos(theta) + old.x[i] * sin(theta);
 287                                 eye.x[i] = old.x[i] * cos(theta) - old.y[i] * sin(theta);
 288                         }
 289                         break;
 290                 }
 291                 // Rotate camera direction CCW about its axis
 292                 // (roll control)
 293                 case 'U':
 294                 case 'u':
 295                 {
 296                         float theta = -M_PI/80.0;
 297                         Camera old = eye;
 298
 299                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 300                         {
 301                                 eye.z[i] = old.z[i] * cos(theta) + old.y[i] * sin(theta);
 302                                 eye.y[i] = old.y[i] * cos(theta) - old.z[i] * sin(theta);
 303                         }
 304                         break;
 305                 }
 306                 // Rotate camera direction CW about its axis
 307                 // (roll control)
 308                 case 'O':
 309                 case 'o':
 310                 {
 311                         float theta = +M_PI/80.0;
 312                         Camera old = eye;
 313
 314                         for (unsigned i = 0; i < DIMENSIONS; ++i)
 315                         {
 316                                 eye.z[i] = old.z[i] * cos(theta) + old.y[i] * sin(theta);
 317                                 eye.y[i] = old.y[i] * cos(theta) - old.z[i] * sin(theta);
 318                         }
 319                         break;
 320                 }
 321         }
 322
 323         /*  Code used for debugging the camera
 324         system("clear");
 325         printf("Camera status:\n");
 326         printf("Position: %f %f %f\n", eye.p[0], eye.p[1], eye.p[2]);
 327         printf("x: %f %f %f (%f)\n", eye.x[0], eye.x[1], eye.x[2], sqrt(eye.x[0]*eye.x[0] + eye.x[1]*eye.x[1] + eye.x[2]*eye.x[2]));
 328         printf("y: %f %f %f (%f)\n", eye.y[0], eye.y[1], eye.y[2], sqrt(eye.y[0]*eye.y[0] + eye.y[1]*eye.y[1] + eye.y[2]*eye.y[2]));
 329         printf("z: %f %f %f (%f)\n", eye.z[0], eye.z[1], eye.z[2], sqrt(eye.z[0]*eye.z[0] + eye.z[1]*eye.z[1] + eye.z[2]*eye.z[2]));
 330         */
 331         #else // The original view code
 332
 333                 // I like how 'I' is used three times.
 334
 335                 if (theKey == 'i' || theKey == 'I') {
 336                         eyePhi -= M_PI / 20;
 337                 if (eyePhi == 0)
 338                                 eyePhi = 2 * M_PI;
 339                 } else if (theKey == 'm' || theKey == 'I') {
 340                         eyePhi += M_PI / 20;
 341                 } else if (theKey == 'j' || theKey == 'J') {
 342                         eyeTheta -= M_PI / 20;
 343                 } else if (theKey == 'k' || theKey == 'K') {
 344                         eyeTheta += M_PI / 20;
 345                 } else if (theKey == ',') {
 346                         eyeRho += 0.5;
 347                 } else if (theKey == '.' || theKey == 'I') {
 348                         eyeRho -= 0.5;
 349                 } else if (theKey == 'w' || theKey == 'W') {
 350                         look[1] += 0.5;
 351                 } else if (theKey == 'z' || theKey == 'Z') {
 352                         look[1] -= 0.5;
 353                 } else if (theKey == 'a' || theKey == 'A') {
 354                         look[0] -= 0.5;
 355                 } else if (theKey == 's' || theKey == 'S') {
 356                         look[0] += 0.5;
 357                 } else if (theKey == '+') {
 358                         scale *= 1.1;
 359                 } else if (theKey == '-') {
 360                         scale *= 0.9;
 361                 }
 362                 if (sin(eyePhi) > 0) upY = 1;
 363                 else upY = 1;
 364         #endif //FLYING_CAMERA
 365 }
 366
 367 /**
 368  * @function Graphics_Reshape
 369  * @purpose Resize the view window
 370  * @param width, height - New size of the window
 371  */
 372 void Graphics_Reshape(int width, int height)
 373 {
 374         double displayRatio = 1.0 * width / height;
 375         windowWidth = width;
 376         windowHeight = height;
 377         glMatrixMode(GL_PROJECTION);
 378         glLoadIdentity();
 379         gluPerspective(VIEW_ANGLE, displayRatio, WORLD_NEAR, WORLD_FAR);
 380         glViewport(0, 0, windowWidth, windowHeight);
 381 }
 382
 383
 384