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
  57         // Check for collisions with paddles
  58         if(ballVecX < 0 && ballX <= -HEIGHT + -ballVecX * 1.5) {
  59                 if(ballY >= paddle1 - PADDLESIZE && ballY <= paddle1 + PADDLESIZE) {
  60                         ballVecX *= -SPEEDINC;
  61                         ballVecY *= SPEEDINC;
  62                 }
  63         }
  64         if(ballVecX > 0 && ballX >=  HEIGHT - ballVecX * 1.5) {
  65                 if(ballY >= paddle2 - PADDLESIZE && ballY <= paddle2 + PADDLESIZE) {
  66                         ballVecX *= -SPEEDINC;
  67                         ballVecY *= SPEEDINC;
  68                 }
  69         }
  70
  71         // Check if it's past the top or bottom of the screen
  72         if(ballY >= HEIGHT || ballY <= -HEIGHT) {
  73                 ballVecY = -ballVecY;
  74         }
  75
  76         // Check if it's past the sides of the screen
  77         if(ballX >= HEIGHT) {
  78                 ++score1;
  79                 initball();
  80         }
  81         if(ballX <= -HEIGHT) {
  82                 ++score2;
  83                 initball();
  84         }
  85
  86         // Move the ball
  87         ballX += ballVecX;
  88         ballY += ballVecY;
  89
  90         // Check scores for winners..
  91         if(score1 == 9) {
  92                 // Player 1 wins
  93                 score1 = score2 = 0;
  94         }
  95         if(score2 == 9) {
  96                 // Player 2 wins
  97                 score1 = score2 = 0;
  98         }
  99 }
 100
 101 static void display(void) {
 102         glClear(GL_COLOR_BUFFER_BIT);
 103         glColor3d(0.0, 0.0, 0.0);
 104
 105         // Draw the paddles
 106         glLineWidth(2.0);
 107         glBegin(GL_LINES);
 108         glVertex2d(-HEIGHT + 1, paddle1 - PADDLESIZE);
 109         glVertex2d(-HEIGHT + 1, paddle1 + PADDLESIZE);
 110         glVertex2d( HEIGHT - 1, paddle2 + PADDLESIZE);
 111         glVertex2d( HEIGHT - 1, paddle2 - PADDLESIZE);
 112         glEnd();
 113
 114         // Draw the ball
 115         glPointSize(5.0);
 116         glBegin(GL_POINTS);
 117         glVertex2d(ballX, ballY);
 118         glEnd();
 119
 120         // Write the score
 121         glRasterPos2d(-5.0, HEIGHT - 10.0);
 122         glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, '0' + score1);
 123         glRasterPos2d( 5.0, HEIGHT - 10.0);
 124         glutBitmapCharacter(GLUT_BITMAP_HELVETICA_18, '0' + score2);
 125
 126         glutSwapBuffers();
 127 }
 128
 129 static void resize(int w, int h) {
 130         glViewport(0, 0, w, h);
 131         glLoadIdentity();
 132         glOrtho(-HEIGHT, HEIGHT, -HEIGHT, HEIGHT, -1.0, 1.0);
 133 }
 134
 135 static void keyboard(unsigned char key, int x, int y) {
 136         (void)x;(void)y;
 137
 138         switch(key) {
 139                 case 'q':
 140                 case 'Q':
 141                 case '\033':
 142                         exit(0);
 143
 144                 case 'w':
 145                         p1move = 1;
 146                         break;
 147                 case 's':
 148                         p1move = -1;
 149                         break;
 150
 151                 case 'i':
 152                         p2move = 1;
 153                         break;
 154                 case 'k':
 155                         p2move = -1;
 156                         break;
 157
 158                 default:
 159                         return;
 160         }
 161         glutPostRedisplay();
 162 }
 163
 164 static void keyboardUp(unsigned char key, int x, int y) {
 165         (void)x;(void)y;
 166
 167         switch(key) {
 168                 case 'w':
 169                 case 's':
 170                         p1move = 0;
 171                         break;
 172
 173                 case 'i':
 174                 case 'k':
 175                         p2move = 0;
 176                         p2move = 0;
 177                         break;
 178         }
 179 }
 180
 181 static void timer(int lastTime) {
 182         int curTime = glutGet(GLUT_ELAPSED_TIME);
 183         do {
 184                 lastTime += FRAME;
 185                 run();
 186         } while(lastTime + FRAME < curTime);
 187         glutPostRedisplay();
 188         glutTimerFunc(FRAME - (curTime - lastTime), timer, curTime);
 189 }
 190
 191 static void init(void) {
 192         glClearColor(1.0, 1.0, 1.0, 0.0);
 193         initball();
 194 }
 195
 196 int main(int argc, char *argv[]) {
 197         if(argc == 2 && *argv[1] == '1') {
 198                 AI = 1;
 199         }
 200
 201         glutInitWindowPosition(100, 100);
 202         glutInitWindowSize(640, 480);
 203         glutInit(&argc, argv);
 204         glutInitDisplayMode(GLUT_RGBA | GLUT_DOUBLE);
 205         glutCreateWindow(argv[0]);
 206         glutDisplayFunc(display);
 207         glutReshapeFunc(resize);
 208         glutKeyboardFunc(keyboard);
 209         glutKeyboardUpFunc(keyboardUp);
 210         glutTimerFunc(FRAME, timer, glutGet(GLUT_ELAPSED_TIME));
 211         init();
 212         glutMainLoop();
 213         return 0;
 214 }
 215