code.delx.au - pong/blob - pong.c

   1 #if defined(WIN32)
   2 #pragma comment(linker, "/subsystem:\"windows\" /entry:\"mainCRTStartup\"")
   3 #include "glut.h"
   4 #elif defined(__APPLE__) || defined(MACOSX)
   5 #include <GLUT/glut.h>
   6 #else
   7 #include <GL/glut.h>
   8 #endif
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12
  13 #define SPEEDINC    1.15
  14 #define PADDLESPEED 2.5
  15 #define FRAME       40
  16 #define PADDLESIZE  10
  17 #define HEIGHT      100
  18
  19 static int AI = 0;
  20 static int p1move = 0;
  21 static int p2move = 0;
  22 static int score1 = 0;
  23 static int score2 = 0;
  24 static GLdouble paddle1 = 0.0;
  25 static GLdouble paddle2 = 0.0;
  26 static GLdouble ballX = 0.0;
  27 static GLdouble ballY = 0.0;
  28 static GLdouble ballVecX = 0.0;
  29 static GLdouble ballVecY = 0.0;
  30
  31
  32 static void initball(void) {
  33         ballX = 0.0;
  34         ballY = 0.0;
  35         if(ballVecX < 0)
  36                 ballVecX = -1.2;
  37         else
  38                 ballVecX = 1.2;
  39         ballVecY = 0.7;
  40 }
  41
  42 static void run(void) {
  43         // AI
  44         if(AI) {
  45                 if(ballY < paddle2 - PADDLESIZE)
  46                         p2move = -1;
  47                 else if(ballY > paddle2 + PADDLESIZE)
  48                         p2move = 1;
  49                 else
  50                         p2move = 0;
  51         }
  52
  53         // Move the paddles
  54         paddle1 += p1move * PADDLESPEED;
  55         paddle2 += p2move * PADDLESPEED;
  56         if(paddle1 < -HEIGHT)
  57                 paddle1 = -HEIGHT;
  58         if(paddle1 > HEIGHT)
  59                 paddle1 = HEIGHT;
  60         if(paddle2 < -HEIGHT)
  61                 paddle2 = -HEIGHT;
  62         if(paddle2 > HEIGHT)
  63                 paddle2 = HEIGHT;
  64
  65         // Check for collisions with paddles
  66         if(ballVecX < 0 && ballX <= -HEIGHT + -ballVecX * 1.5) {
  67                 if(ballY >= paddle1 - PADDLESIZE && ballY <= paddle1 + PADDLESIZE) {
  68                         ballVecX *= -SPEEDINC;
  69                         ballVecY *= SPEEDINC;
  70                 }
  71         }
  72         if(ballVecX > 0 && ballX >=  HEIGHT - ballVecX * 1.5) {
  73                 if(ballY >= paddle2 - PADDLESIZE && ballY <= paddle2 + PADDLESIZE) {
  74                         ballVecX *= -SPEEDINC;
  75                         ballVecY *= SPEEDINC;
  76                 }
  77         }
  78
  79         // Check if it's past the top or bottom of the screen
  80         if(ballY >= HEIGHT || ballY <= -HEIGHT) {
  81                 ballVecY = -ballVecY;
  82         }
  83
  84         // Check if it's past the sides of the screen
  85         if(ballX >= HEIGHT) {
  86                 ++score1;
  87                 initball();
  88         }
  89         if(ballX <= -HEIGHT) {
  90                 ++score2;
  91                 initball();
  92         }
  93
  94         // Move the ball
  95         ballX += ballVecX;
  96         ballY += ballVecY;
  97
  98         // Check scores for winners..
  99         if(score1 == 9) {
 100                 // Player 1 wins
 101                 score1 = score2 = 0;
 102         }
 103         if(score2 == 9) {
 104                 // Player 2 wins
 105                 score1 = score2 = 0;
 106         }
 107 }
 108
 109 static void display(void) {
 110         glClear(GL_COLOR_BUFFER_BIT);
 111         glColor3d(0.0, 0.0, 0.0);
 112
 113         // Draw the paddles
 114         glLineWidth(2.0);
 115         glBegin(GL_LINES);
 116         glVertex2d(-HEIGHT + 1, paddle1 - PADDLESIZE);
 117         glVertex2d(-HEIGHT + 1, paddle1 + PADDLESIZE);
 118         glVertex2d( HEIGHT - 1, paddle2 + PADDLESIZE);
 119         glVertex2d( HEIGHT - 1, paddle2 - PADDLESIZE);
 120         glEnd();
 121
 122         // Draw the ball
 123         glPointSize(5.0);
 124         glBegin(GL_POINTS);
 125         glVertex2d(ballX, ballY);
 126         glEnd();
 127
 128         // Write the score
 129         glRasterPos2d(-5.0, HEIGHT - 10.0);
 130         glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, '0' + score1);
 131         glRasterPos2d( 5.0, HEIGHT - 10.0);
 132         glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, '0' + score2);
 133
 134         glutSwapBuffers();
 135 }
 136
 137 static void resize(int w, int h) {
 138         glViewport(0, 0, w, h);
 139         glLoadIdentity();
 140         glOrtho(-HEIGHT, HEIGHT, -HEIGHT, HEIGHT, -1.0, 1.0);
 141 }
 142
 143 static void keyboard(unsigned char key, int x, int y) {
 144         (void)x;(void)y;
 145
 146         switch(key) {
 147                 case 'q':
 148                 case 'Q':
 149                 case '\033':
 150                         exit(0);
 151
 152                 case 'w':
 153                         p1move = 1;
 154                         break;
 155                 case 's':
 156                         p1move = -1;
 157                         break;
 158
 159                 case 'i':
 160                         p2move = 1;
 161                         break;
 162                 case 'k':
 163                         p2move = -1;
 164                         break;
 165
 166                 default:
 167                         return;
 168         }
 169         glutPostRedisplay();
 170 }
 171
 172 static void keyboardUp(unsigned char key, int x, int y) {
 173         (void)x;(void)y;
 174
 175         switch(key) {
 176                 case 'w':
 177                 case 's':
 178                         p1move = 0;
 179                         break;
 180
 181                 case 'i':
 182                 case 'k':
 183                         p2move = 0;
 184                         p2move = 0;
 185                         break;
 186         }
 187 }
 188
 189 static void timer(int lastTime) {
 190         int curTime = glutGet(GLUT_ELAPSED_TIME);
 191         do {
 192                 lastTime += FRAME;
 193                 run();
 194         } while(lastTime + FRAME < curTime);
 195         glutPostRedisplay();
 196         glutTimerFunc(FRAME - (curTime - lastTime), timer, curTime);
 197 }
 198
 199 static void init(void) {
 200         glClearColor(1.0, 1.0, 1.0, 0.0);
 201         initball();
 202 }
 203
 204 int main(int argc, char *argv[]) {
 205         if(argc == 2 && *argv[1] == '1') {
 206                 AI = 1;
 207         }
 208
 209         glutInitWindowPosition(100, 100);
 210         glutInitWindowSize(640, 480);
 211         glutInit(&argc, argv);
 212         glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE);
 213         glutCreateWindow(argv[0]);
 214         glutDisplayFunc(display);
 215         glutReshapeFunc(resize);
 216         glutKeyboardFunc(keyboard);
 217         glutKeyboardUpFunc(keyboardUp);
 218         glutTimerFunc(FRAME, timer, glutGet(GLUT_ELAPSED_TIME));
 219         init();
 220         glutMainLoop();
 221         return 0;
 222 }
 223