// 16 memory cells from the matrix of 16x16 and then averages
               // the info, that is, they exchange information
               // this takes 1 unit of energy

               // time to exchange memory?
               if (++ants[index].counter_2 >= 3)
                  {
                  // reset counter
                  ants[index].counter_2 = 0;
                  
                  // select cell to exchange and exchange memory imprints
                  int memx = rand()%16;
                  int memy = rand()%16;

                  // sum with partners experience
                  ants_mem[index].cell[memx][memy] += 
                    0.5*ants_mem[ants[index].varsI[ANT_INDEX_LAST_TALKED_WITH]].cell[memx][memy];
     
                  // illuminate green to show communication
                  ants_mem[index].ilayer[memx][memy] = 250;
             
                  } // end if

               // test if we are done with this state and need a new one?
               if (--ants[index].counter_1 < 0 || 
                ants[ants[index].varsI[ANT_INDEX_LAST_TALKED_WITH]].varsI[ANT_INDEX_AI_STATE]!=ANT_COMMUNICATING)                                        
                  {
                  // select either rest or wander, search will pre-empt with logic following
                  // if hungry, state, probability of state, must sum to 100
                  select_new_state = Select_State_Rand(ANT_WANDERING,     90,            
                                                       ANT_EATING,        0,                
                                                       ANT_RESTING,       10,              
                                                       ANT_SEARCH_FOOD,   0,           
                                                       ANT_COMMUNICATING, 0,         
                                                       ANT_DEAD,          0);                    
                   } // end if


               // burn food
               ants[index].varsI[ANT_INDEX_HUNGER_LEVEL]++;

               // test for pre-empt into search mode if hunger is 50% tolerance
               if (ants[index].varsI[ANT_INDEX_HUNGER_LEVEL] > (ants[index].varsI[ANT_INDEX_HUNGER_TOLERANCE] >> 1) )
                  {
                  select_new_state = ANT_SEARCH_FOOD;
                  } // end if    

               } break;

          case ANT_DEAD:           // this guy is dead, got too hungry
               {
               // the any just sits there and is worm food, no enery expended          

 
               } break;

          default: break;

          } // end switch

    // was there a forced state transition?
if (ants[index].varsI[ANT_INDEX_AI_STATE]!=ANT_DEAD && 
   (ants[index].varsI[ANT_INDEX_HUNGER_LEVEL] >= ants[index].varsI[ANT_INDEX_HUNGER_TOLERANCE]))
   {
   // dead ant
   select_new_state = ANT_DEAD;

   } // end if

///////////////////////////////////////////////////////////////////////////

        // add a little forgetfulness, select a memory at random and weaken it
        int memx = rand()%16;
        int memy = rand()%16;

       ants_mem[index].ilayer[memx][memy] = 249; // illuminate red to show degradation

        if (ants_mem[index].cell[memx][memy] > 5)
           {
           ants_mem[index].cell[memx][memy]-=rand()%5;
           } // end if

//////////////////////////////////////////////////////////////////////////

// set new state if needed 
    if (select_new_state >= 0)
       {
       // set the state
       Set_New_State(select_new_state, index);
     
       } // end if
////////////////////////////////////////////////////

   // clear the memory matrix
   if (clear_ilayer >= 5)
      memset(ants_mem[index].ilayer,0, 1024);


   // this point is where the "physics" system need to operate
   // have any of the state changes or motions caused a physical problem
   // in the universe, we could do it in each state, but this is simpler

   // test for out of bounds
   if (ants[index].x > 472)
       {
       // bounce back a bit
       ants[index].x-=4;

       // turn to new heading
       switch(rand()%3)
             {
             case 0: ants[index].varsI[ANT_INDEX_DIRECTION] = ANT_ANIM_LEFT; break;
             case 1: ants[index].varsI[ANT_INDEX_DIRECTION] = ANT_ANIM_UP; break;
             case 2: ants[index].varsI[ANT_INDEX_DIRECTION] = ANT_ANIM_DOWN; break;
             default: break;
             } // end switch
     
       // add a little time to counters     
       ants[index].counter_2 += RAND_RANGE(30, 60);
       ants[index].counter_1 += RAND_RANGE(15, 30);

       // start animation
       Set_Animation_BOB(&ants[index], ants[index].varsI[ANT_INDEX_DIRECTION]);

       } // end if
else
if (ants[index].x <= 16)
    {
    // bounce back a bit
    ants[index].x+=4;

    // turn to new heading
    switch(rand()%3)
          {
          case 0: ants[index].varsI[ANT_INDEX_DIRECTION] = ANT_ANIM_RIGHT; break;
          case 1: ants[index].varsI[ANT_INDEX_DIRECTION] = ANT_ANIM_UP; break;
          case 2: ants[index].varsI[ANT_INDEX_DIRECTION] = ANT_ANIM_DOWN; break;
          default: break;
          } // end switch
     
    // add a little time to counter     
    ants[index].counter_2 += RAND_RANGE(30, 60);
    ants[index].counter_1 += RAND_RANGE(15, 30);

    // start animation
    Set_Animation_BOB(&ants[index], ants[index].varsI[ANT_INDEX_DIRECTION]);

    } // end if

if (ants[index].y < 0)
    ants[index].y = screen_height;
else
if (ants[index].y > screen_height)
    ants[index].y = 0;

///////////////////////////////////////////////////////////////////////////////////

    } // end for index

// update global memory clear counter
if (++clear_ilayer > 5)
    clear_ilayer= 0;



} // end Move_Ants

///////////////////////////////////////////////////////////////////

void Draw_Food(void)
{
// draw the food

int index;

for (index=0; index<NUM_MNMS; index++)
    {
    if (food[index].energy > 0)
       {
       // set position of mnm
       Set_Pos_BOB(&mnm, food[index].x-4, food[index].y-4);
       Draw_BOB(&mnm, lpddsback);
       } // end if

    } // end for index

} // end Draw_Food

///////////////////////////////////////////////////////////////////

void Draw_Info(void)
{
// this function draws the state information for 8 ants

static char *state_to_text[6] = {"Wander", "Eating", "Resting", "Srchfood", "Talking", "Dead"};         

static int intensity_to_index[16] = {0,65,94,151,166,175,203,208,221,227,233,236,239,242,245,245};

#define DELTA_LINE 14

for (int index=0; index < NUM_ANTS; index++)
    {
    int px = 480;
    int py = 8+index * 60;


    // only show infor for first 8 ants
    if (index < 8 )
    {
    // print name of ant and state
    sprintf(buffer,"Ant%d=%s,%d", index, state_to_text[ants[index].varsI[ANT_INDEX_AI_STATE]], ants[index].varsI[ANT_INDEX_AI_SUBSTATE]);    
    Draw_Text_GDI(buffer,px, py, RGB(0,255,0),lpddsback);


    // print counters
    sprintf(buffer, "C1:%d,C2:%d", ants[index].counter_1, ants[index].counter_2);
    Draw_Text_GDI(buffer,px, py+DELTA_LINE, RGB(0,255,0),lpddsback);

    // print hunger level and tolerance
    sprintf(buffer,"Hungr:%d,Tol:%d", ants[index].varsI[ANT_INDEX_HUNGER_LEVEL],
                                      ants[index].varsI[ANT_INDEX_HUNGER_TOLERANCE]);

    Draw_Text_GDI(buffer,px, py+2*DELTA_LINE, RGB(0,255,0),lpddsback);

    // draw memory, the brighter the green dot, the stronger the memory
    Draw_Rectangle(px+124, py, px+124+18, py+18, 0, lpddsback);

    // dont draw memory if ant dead
    if (ants[index].varsI[ANT_INDEX_AI_STATE]!=ANT_DEAD)
    {
    DDraw_Lock_Back_Surface();
    for (int x = 0; x<16; x++)
        for (int y=0; y<16; y++)
            {
            // get memory and convert into pixel value to disply
            // dark means low recall, bright white means strong memory of food
            float mem_strength = ants_mem[index].cell[x][y];

            // each mnm is worth on average 500, so if a cell has a 2500 then we know there is 
            // a lot of food, use this as the highest strength
            if (mem_strength > 2500)
               mem_strength = 2500;

            // normalize and scale to color range
            int color_intensity = (int)((mem_strength/2500)*15);
            Draw_Pixel(px+124+x+1,py+y+1, intensity_to_index[color_intensity], back_buffer, back_lpitch);
      
            int active_pixel = ants_mem[index].ilayer[x][y];

            if (active_pixel)
               // scan input layer to see where degradation and communication have taken place
               Draw_Pixel(px+124+x+1,py+y+1, active_pixel, back_buffer, back_lpitch);
            } // end for

        DDraw_Unlock_Back_Surface();
       } // end if
       else
           // draw flat line :)
           {
           DDraw_Lock_Back_Surface();
           HLine(px+124,px+124+18, py+9, 249, back_buffer, back_lpitch);
           DDraw_Unlock_Back_Surface();
           } // end else

       } // end if < 8

    } // end for index

} // end Draw_Info


////////////////////////////////////////////////////////////////////

int Game_Main(void *parms)
{
// this is the workhorse of your game it will be called
// continuously in real-time this is like main() in C
// all the calls for you game go here!

int index; // looping var


// start the timing clock
Start_Clock();

// clear the drawing surface
DDraw_Fill_Surface(lpddsback, 0);

// lock back buffer and copy background into it
DDraw_Lock_Back_Surface();

// draw background
Draw_Bitmap(&background_bmp, back_buffer, back_lpitch,0);

// unlock back surface
DDraw_Unlock_Back_Surface();

// read keyboard
DInput_Read_Keyboard();

// move ants and perform ai
Move_Ants();

// draw the food
Draw_Food();

// draw ants and animate imagery
Draw_Ants(); 

// draw info
Draw_Info();


sprintf(buffer,"Artificial Intelligence Memory Demo. Press <ESC> to Exit.");
Draw_Text_GDI(buffer,8, 8,RGB(255,255,255),lpddsback);

// flip the surfaces
DDraw_Flip();

// sync to 30ish fps
Wait_Clock(30);

// check of user is trying to exit
if (KEY_DOWN(VK_ESCAPE) || keyboard_state[DIK_ESCAPE])
    {
    PostMessage(main_window_handle, WM_DESTROY,0,0);

    // stop all sounds
    DSound_Stop_All_Sounds();

    // do a screen transition
    Screen_Transitions(SCREEN_DARKNESS,NULL,0);

    } // end if

// return success
return(1);

} // end Game_Main

//////////////////////////////////////////////////////////