main.c

//initializing lists and setting balls into list
	SDL_Event event;
    int quitting = 0;
	int i;
	int listsize;
    list_iterator_t *iter;
	list_t *list=list_create();
	iter = list_createiterator(list);
	listsize=list_size(list);
	object_t *ball;
	for(i = 0; i < 5; i++){
		
		ball = CreateObject(screen,sphere_model,SPHERE_NUMTRIANGLES);
		printf("SpeedX: %f\tSpeedy: %f\tTX: %f\t TY: %f\n", ball->speedx, ball->speedy,ball->tx, ball->ty);
		list_addlast(list,ball);
	}		
	//initiliazing animation 
    while(!quitting)
    {
      ClearScreen(screen);
      /* Event-loop: goes through the event queue
       * responding to the events we care about.
       */
      while (SDL_PollEvent(&event))
      {
        switch (event.type)
        {
          case SDL_QUIT: // Quit events include Alt-F4, Ctrl-C, closing the window
            quitting = 1;
            break;
          case SDL_KEYDOWN:
            if (event.key.keysym.sym == SDLK_ESCAPE) // Quit with escape
              quitting = 1;
        }
      }
	 
	 
	 list_resetiterator(iter);

	//animation loop
	while((ball=list_next(iter))){
		
    DrawObject(ball);
	ball->tx += ball->speedx;
	ball->ty += ball->speedy;
	ball->rotation+=ball->speedx;
	if(ball->tx + ball->radius >= screen->w || ball->tx - ball->radius <= 0)
			ball->speedx *= -1;
		
	
	    
	if(ball->ty + ball->radius >= screen->h || ball->ty - ball->radius <= 0){
			ball->speedy *= -1;
			
	if(ball->speedx > 0.3 || ball->speedx < -0.3) {
			if(ball->speedx > 0)
					ball->speedx -= 0.5;
				
	else if(ball->speedx < 0)
					ball->speedx += 0.5; 
				
			}
		else 
				ball->speedx = 0.0;
			
	if((ball->speedy < 0.5 && ball->speedy > -0.5) || (ball->speedy > -0.5 && ball->speedy < -0.5))
				ball->speedy = 0;
		}

	if(ball->speedy > 0.0)
			ball->speedy += 0.5;

		else if(ball->speedy < 0.0)
			ball->speedy += 0.7;
			
	
	if(ball->speedx > 0)
			ball->speedx -= 0.015;
		else if(ball->speedx < 0)
			ball->speedx += 0.015;
		
	ball->ttl=0;
	if(ball->speedy==0){
		SDL_Delay(500);
		ball->ttl=ball->speedy;
			
		}
		if(ball->ttl==ball->speedy){
			list_remove(list,ball);
			DestroyObject(ball);
		}
		
		printf("SpeedX: %f\tSpeedY: %f\t\n", ball->speedx,ball->speedy);
	 }
      SDL_UpdateRect(screen, 0, 0, 0, 0);
    }