Snake part1

#include <stdio.h>
#include <time.h>

#include <GL/glut.h>




#define UP 1
#define DOWN 2
#define LEFT 3
#define RIGHT 4

GLint   lvl      = 1;
GLbyte  keys  = 0;
GLint   _w       = 400;
GLint   _h       = 350;
GLint   _Giw     = 10;
GLint   _Gih     = 30;
GLint   _Gfw     = 270;
GLint   _Gfh     = 240;
GLint   tamanho  = 0;
GLint   body[2][30] = {{}};
GLint   oldX[2] = {};
GLint   oldY[2] = {};


struct SnakeHead {
GLint   x;      
GLint   y;    
} head ={10, 20};


void snake(){
     int  i;

     //head
     glPushMatrix();
     glTranslatef(head.x, head.y,0.0);
     glColor3f(1, 0, 0);
     glRectf(10.0f, 10.0f, 20.0f, 20.0f);
     glPopMatrix();

     // boody
     for(i=0; i<tamanho; i++){
          glPushMatrix();
          glTranslatef(body[0][i],body[1][i],0.0);
          glColor3f(1, 0, 0);
          glRectf(10.0f, 10.0f, 20.0f, 20.0f);
          glPopMatrix();
     }
}

void go(int value){
     int i;

     oldX[1] = head.x;
     oldY[1] = head.y;
     switch(keys){
      case RIGHT:
         head.x += 10;   
         if(head.x > _Gfw-20)head.x = _Giw-10;
         break;
      case LEFT:
         head.x-= 10;   
         if(head.x < 0) head.x = _Gfw-20;
         break;
      case UP:
         head.y += 10;   
         if(head.y > _Gfh-20)head.y = _Gih-10;
         break;
      case DOWN:
         head.y -= 10;   
         if(head.y < 20) head.y = _Gfh-20;
         break;
     }

 //    if(colisao()) gameOver = true;



     for(i = 0; i<tamanho; i++){
          oldX[0]       = oldX[1];
          oldY[0]       = oldY[1];
          oldX[1]       = body[0][i];
          oldY[1]       = body[1][i];
          body[0][i] = oldX[0];
          body[1][i] = oldY[0];
     }

     glutTimerFunc(140-lvl*8, go, 0);                   
}

void keybord(int key, int x, int y){
   switch(key) {
    case GLUT_KEY_RIGHT     :
         if(keys != LEFT)
           keys = RIGHT;
         break;
    case GLUT_KEY_LEFT      :
         if(keys != RIGHT)
           keys = LEFT;
         break;
    case GLUT_KEY_UP        :
         if(keys != DOWN)
           keys = UP;
         break;
    case GLUT_KEY_DOWN      :
         if(keys != UP)
           keys = DOWN;
         break;
   }
}


 void Display(void){

     glClear(GL_COLOR_BUFFER_BIT);

         snake();




 
     glutPostRedisplay();
     glutSwapBuffers();
}

void Reshape(GLsizei w, GLsizei h){
     glViewport(0, 0, _w, _h);
     glMatrixMode(GL_PROJECTION);
     glLoadIdentity();
     if (w <= h)
        gluOrtho2D (0.0f, 250.0f, 0.0f, 250.0f*_h/_w);
     else
        gluOrtho2D (0.0f, 250.0f*_w/_h, 0.0f, 250.0f);
}

void init (void){  
     glClearColor(1.0f, 1.0f, 1.0f, 1.0f);
}

int main(int argc, char** argv){
    glutInit(&argc, argv);
     glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
     glutInitWindowSize(_w,_h);
     glutInitWindowPosition(500,400);
     glutCreateWindow("snake");
     glutDisplayFunc(Display);
 glutReshapeFunc(Reshape);
    glutSpecialFunc(keybord);
   go(0);
init();
     glutMainLoop();
}