int Game_Shutdown(void *parms,  int num_parms)
{
// this function is where you shutdown your game and
// release all resources that you allocated

// first unacquire the mouse
lpdimouse->Unacquire();

// now release the mouse
lpdimouse->Release();

// release directinput
lpdi->Release();

// unload the bitmap file
Unload_Bitmap_File(&bitmap8bit);

// delete all bobs and bitmaps
Destroy_BOB(&buttons);
Destroy_BOB(&pointer);
Destroy_Bitmap(&cpanel);
Destroy_Bitmap(&canvas);

// shutdonw directdraw
DDraw_Shutdown();

// return success
return(1);
} // end Game_Shutdown

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

int Game_Main(void *parms, int num_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


// check of user is trying to exit
if (KEY_DOWN(VK_ESCAPE) || KEY_DOWN(VK_SPACE))
    PostMessage(main_window_handle, WM_DESTROY,0,0);

// start the timing clock
Start_Clock();

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

// get the input from the mouse
lpdimouse->GetDeviceState(sizeof(DIMOUSESTATE), (LPVOID)&mouse_state);

// move the mouse cursor
mouse_x+=(mouse_state.lX);
mouse_y+=(mouse_state.lY);

// test bounds

// first x boundaries
if (mouse_x >= screen_width)
   mouse_x = screen_width-1;
else
if (mouse_x < 0)
   mouse_x = 0;

// now the y boundaries
if (mouse_y >= screen_height)
   mouse_y= screen_height-1;
else
if (mouse_y < 0)
   mouse_y = 0;

// position the pointer bob to the mouse coords
pointer.x = mouse_x - 16;
pointer.y = mouse_y - 16;

// test what the user is doing with the mouse
if ((mouse_x > 3) && (mouse_x < 500-3) && 
    (mouse_y > 3) && (mouse_y < SCREEN_HEIGHT-3))
   {
   // mouse is within canvas region

   // if left button is down then draw
   if (mouse_state.rgbButtons[0])
      {
      // test drawing mode
      if (buttons_state[BUTTON_PENCIL])
         {
         // draw a pixel 
         Draw_Pixel(mouse_x, mouse_y, mouse_color, canvas.buffer, canvas.width);
         Draw_Pixel(mouse_x+1, mouse_y, mouse_color, canvas.buffer, canvas.width);
         Draw_Pixel(mouse_x, mouse_y+1, mouse_color, canvas.buffer, canvas.width);
         Draw_Pixel(mouse_x+1, mouse_y+1, mouse_color, canvas.buffer, canvas.width);
         }
      else
         {
         // draw spray
         for (index=0; index<10; index++)
             {
             // get next particle
             int sx=mouse_x-8+rand()%16;
             int sy=mouse_y-8+rand()%16;
            
             // make sure particle is in bounds
             if (sx > 0 && sx < 500 && sy > 0 && sy < screen_height)
                Draw_Pixel(sx, sy, mouse_color, canvas.buffer, canvas.width);
             } // end for index

         } // end else

      } // end if left button
    else // right button is eraser
    if (mouse_state.rgbButtons[1])
       {
       // test drawing mode
       if (buttons_state[BUTTON_PENCIL]) 
          {
          // erase a pixel 
          Draw_Pixel(mouse_x, mouse_y, 0, canvas.buffer, canvas.width);
          Draw_Pixel(mouse_x+1, mouse_y, 0, canvas.buffer, canvas.width);
          Draw_Pixel(mouse_x, mouse_y+1, 0, canvas.buffer, canvas.width);
          Draw_Pixel(mouse_x+1, mouse_y+1, 0, canvas.buffer, canvas.width);
          } // end if
       else
          {
          // erase spray
          for (index=0; index<20; index++)
              {
              // get next particle
              int sx=mouse_x-8+rand()%16;
              int sy=mouse_y-8+rand()%16;
            
              // make sure particle is in bounds
              if (sx > 0 && sx < 500 && sy > 0 && sy < screen_height)
                 Draw_Pixel(sx, sy, 0, canvas.buffer, canvas.width);
              } // end for index
          
          } // end else
       
       } // end if left button
  
   } // end if
else
if ( (mouse_x > 500+16) && (mouse_x < 500+16+8*9) &&
     (mouse_y > 8)      && (mouse_y < 8+32*9))
   {
   // within palette

   // test if button left button is down
   if (mouse_state.rgbButtons[0])
      {
      // see what color cell user is pointing to
      int cell_x = (mouse_x - (500+16))/9;
      int cell_y = (mouse_y - (8))/9;

      // change color
      mouse_color = cell_x + cell_y*8;

      } // end if
   } // end if
else
if ((mouse_x > 500) && (mouse_x < (500+100)) &&
    (mouse_y > 344) && (mouse_y < (383+34)) )
   {  
   // within button area
   // test for each button
   for (index=0; index<4; index++)
       {
       if ((mouse_x > buttons_x[index]) && (mouse_x < (buttons_x[index]+32)) &&
           (mouse_y > buttons_y[index]) && (mouse_y < (buttons_y[index]+34)) )
           break;

       } // end for

   // at this point we know where the user is, now determine what he
   // is doing with the buttons
   switch(index)
         {
         case BUTTON_SPRAY:
             {
             // if left button is down simply activate spray mode
             if (mouse_state.rgbButtons[0])
                {
                // depress button
                buttons_state[index] = 1;

               // de-activate pencil mode
                buttons_state[BUTTON_PENCIL] = 0;
                } // end if
             else
                {
                // make sure button is up
                // buttons_state[index] = 0;
                } // end else

             } break;
         
         case BUTTON_PENCIL:
             {
             // if left button is down activate spray mode
             if (mouse_state.rgbButtons[0])
                {
                // depress button
                buttons_state[index] = 1;

                // de-activate spray mode
                buttons_state[BUTTON_SPRAY] = 0;

                } // end if
             else
                {
                // make sure button is up
                // buttons_state[index] = 0;
                } // end else

             } break;

         case BUTTON_ERASE:
             {
             // test if left button is down, if so clear screen
             if (mouse_state.rgbButtons[0])
                {
                // clear memory
                memset(canvas.buffer,0,canvas.width*canvas.height);

                // depress button
                buttons_state[index] = 1;
                } // end if
             else
                {
                // make sure button is up
                buttons_state[index] = 0;
                } // end else
             } break;
         
         case BUTTON_EXIT:
             {
             // test if left button down, if so bail
             if (mouse_state.rgbButtons[0])
                  PostMessage(main_window_handle, WM_DESTROY,0,0);

             } break;

         } // end switch

   } // end if
else
   {
   // no mans land

   } // end else

// lock back buffer
DDraw_Lock_Back_Surface();

// draw the canvas
Draw_Bitmap(&canvas, back_buffer, back_lpitch,0);

// draw control panel
Draw_Bitmap(&cpanel,back_buffer,back_lpitch,0);

// unlock back buffer
DDraw_Unlock_Back_Surface();

// draw the color palette
for (int col=0; col < 256; col++)
    {
    Draw_Rectangle(500+16+(col%8)*9,   8+(col/8)*9,
                   500+16+(col%8)*9+8, 8+(col/8)*9+8,
                   col,lpddsback);
    
    } // end for col

// draw the current color selected
Draw_Rectangle(533,306,533+34,306+34,mouse_color,lpddsback);

// draw the buttons
for (index=0; index<4; index++)
    {
    // set position of button bob
    buttons.x = buttons_x[index];
    buttons.y = buttons_y[index];

    // now select the on/off frame based on if the
    // button is off
    if (buttons_state[index]==0)
        buttons.curr_frame = index;
    else // button is on
        buttons.curr_frame = index+4;

    // draw the button
    Draw_BOB(&buttons, lpddsback);

    } // end for index

static int green = 0;

// display coords
sprintf(buffer,"Pointer (%d,%d)",mouse_x,mouse_y);
Draw_Text_GDI(buffer, 8,screen_height - 16,RGB(0,255,0),lpddsback);
Draw_Text_GDI("T3D Paint Version 2.0 - Press <ESC> to Exit.",0,0,RGB(0,(green & 255),0),lpddsback);

// a little animation
++green;

// draw the cursor last
Draw_BOB(&pointer,lpddsback);

// flip the surfaces
DDraw_Flip();

// sync to 30 fps
Wait_Clock(30);

// return success
return(1);

} // end Game_Main

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