} // end Init_Stars

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

void Move_Stars(void)
{
// this function moves the star field, note that the star field is always
// in screen coordinates, otherwise, we would need thousands of stars to
// fill up the universe instead of 50!

int index,   // looping variable
    star_x,  // used as fast aliases to star position
    star_y,
    plane_0_dx,
    plane_0_dy,
    plane_1_dx,
    plane_1_dy,
    plane_2_dx,
    plane_2_dy;

// pre-compute plane translations
plane_0_dx = -int(player_xv) >> 2;
plane_0_dy = -int(player_yv) >> 2;

plane_1_dx = -int(player_xv) >> 1;
plane_1_dy = -int(player_yv) >> 1;

plane_2_dx = -int(player_xv);
plane_2_dy = -int(player_yv);

// move all the stars based on the motion of the player

for (index=0; index < MAX_STARS; index++)
    {
    // locally cache star position to speed up calculations
    star_x = stars[index].x;
    star_y = stars[index].y;

    // test which star field star is in so it is translated with correct
    // perspective

    switch(stars[index].plane)
          {
          case STAR_PLANE_0:
               {
               // move the star based on differntial motion of player
               // far plane is divided by 4

               star_x+=plane_0_dx;
               star_y+=plane_0_dy;

               } break;

          case STAR_PLANE_1:
               {
               // move the star based on differntial motion of player
               // middle plane is divided by 2

               star_x+=plane_1_dx;
               star_y+=plane_1_dy;

               } break;

          case STAR_PLANE_2:
               {
               // move the star based on differntial motion of player
               // near plane is divided by 1

               star_x+=plane_2_dx;
               star_y+=plane_2_dy;

               } break;

          } // end switch plane

    // test if a star has flown off an edge

    if (star_x >= SCREEN_WIDTH)
        star_x = star_x-SCREEN_WIDTH;
    else
    if (star_x < 0)
        star_x = SCREEN_WIDTH + star_x;

    if (star_y >= SCREEN_HEIGHT)
        star_y = star_y-SCREEN_HEIGHT;
    else
    if (star_y < 0)
        star_y = SCREEN_HEIGHT+star_y;

    // reset stars position in structure
    stars[index].x = star_x;
    stars[index].y = star_y;

    } // end for index

} // end Move_Stars

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

void Draw_Stars(void)
{
// this function draws all the stars

// lock back surface
DDraw_Lock_Back_Surface();

// draw all the stars
for (int index=0; index < MAX_STARS; index++)
    {
    // draw stars 
    Draw_Pixel(stars[index].x,stars[index].y, stars[index].color,back_buffer, back_lpitch);

    } // end for index

// unlock the secondary surface
DDraw_Unlock_Back_Surface();

} // end Draw_Stars

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

void Draw_Scanner(void)
{
// this function draws the scanner

int index,sx,sy; // looping and position

// lock back surface
DDraw_Lock_Back_Surface();

// draw all the rocks
for (index=0; index < MAX_ROCKS; index++)
    {
    // draw rock blips
	if (rocks[index].state==ROCK_STATE_ON)
		{
		sx = ((rocks[index].varsI[INDEX_WORLD_X] - UNIVERSE_MIN_X) >> 7) + (SCREEN_WIDTH/2) - ((UNIVERSE_MAX_X - UNIVERSE_MIN_X) >> 8);
		sy = ((rocks[index].varsI[INDEX_WORLD_Y] - UNIVERSE_MIN_Y) >> 7) + 32;
	    
		Draw_Pixel(sx,sy,8,back_buffer, back_lpitch);
		} // end if

    } // end for index


// draw all the gunships
for (index=0; index < MAX_GUNSHIPS; index++)
    {
    // draw gunship blips
	if (gunships[index].state==GUNSHIP_STATE_ALIVE)
		{
		sx = ((gunships[index].varsI[INDEX_WORLD_X] - UNIVERSE_MIN_X) >> 7) + (SCREEN_WIDTH/2) - ((UNIVERSE_MAX_X - UNIVERSE_MIN_X) >> 8);
		sy = ((gunships[index].varsI[INDEX_WORLD_Y] - UNIVERSE_MIN_Y) >> 7) + 32;
	    
		Draw_Pixel(sx,sy,14,back_buffer, back_lpitch);
		Draw_Pixel(sx+1,sy,14,back_buffer, back_lpitch);

		} // end if

    } // end for index

// draw all the mines
for (index=0; index < MAX_MINES; index++)
    {
    // draw gunship blips
	if (mines[index].state==MINE_STATE_ALIVE)
		{
		sx = ((mines[index].varsI[INDEX_WORLD_X] - UNIVERSE_MIN_X) >> 7) + (SCREEN_WIDTH/2) - ((UNIVERSE_MAX_X - UNIVERSE_MIN_X) >> 8);
		sy = ((mines[index].varsI[INDEX_WORLD_Y] - UNIVERSE_MIN_Y) >> 7) + 32;
	    
		Draw_Pixel(sx,sy,12,back_buffer, back_lpitch);
		Draw_Pixel(sx,sy+1,12,back_buffer, back_lpitch);

		} // end if

    } // end for index

// unlock the secondary surface
DDraw_Unlock_Back_Surface();

// draw all the stations
for (index=0; index < MAX_STATIONS; index++)
    {
    // draw station blips
	if (stations[index].state==STATION_STATE_ALIVE)
		{
		sx = ((stations[index].varsI[INDEX_WORLD_X] - UNIVERSE_MIN_X) >> 7) + (SCREEN_WIDTH/2) - ((UNIVERSE_MAX_X - UNIVERSE_MIN_X) >> 8);
		sy = ((stations[index].varsI[INDEX_WORLD_Y] - UNIVERSE_MIN_Y) >> 7) + 32;
	    
        // test for state
		if (stations[index].anim_state == STATION_SHIELDS_ANIM_ON)
			{
            stationsmall.curr_frame = 0;
            stationsmall.x = sx - 3;
            stationsmall.y = sy - 3; 
            Draw_BOB(&stationsmall,lpddsback);            


			} // end if
		else
			{

            stationsmall.curr_frame = 1;
            stationsmall.x = sx - 3;
            stationsmall.y = sy - 3; 
            Draw_BOB(&stationsmall,lpddsback);  


			} // end if

		} // end if

    } // end for index


// unlock the secondary surface
DDraw_Lock_Back_Surface();

// draw player as white blip
sx = ((int(player_x) - UNIVERSE_MIN_X) >> 7) + (SCREEN_WIDTH/2) - ((UNIVERSE_MAX_X - UNIVERSE_MIN_X) >> 8);
sy = ((int(player_y) - UNIVERSE_MIN_Y) >> 7) + 32;

int col = rand()%256;

Draw_Pixel(sx,sy,col,back_buffer, back_lpitch);
Draw_Pixel(sx+1,sy,col,back_buffer, back_lpitch);
Draw_Pixel(sx,sy+1,col,back_buffer, back_lpitch);
Draw_Pixel(sx+1,sy+1,col,back_buffer, back_lpitch);

// unlock the secondary surface
DDraw_Unlock_Back_Surface();

// now draw the art around the edges

hud.x          = 320-64;
hud.y          = 32-4;
hud.curr_frame = 0;
Draw_BOB(&hud,lpddsback);

hud.x          = 320+64-16;
hud.y          = 32-4;
hud.curr_frame = 1;
Draw_BOB(&hud,lpddsback);

hud.x          = 320-64;
hud.y          = 32+128-20;
hud.curr_frame = 2;
Draw_BOB(&hud,lpddsback);


hud.x          = 320+64-16;
hud.y          = 32+128-20;
hud.curr_frame = 3;
Draw_BOB(&hud,lpddsback);


} // end Draw_Scanner


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

void Init_Stations(void)
{
// this function loads and initializes the stations to a known state
	
static int shields_on_anim[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15},
           shields_off_anim[1] = {16};

int frame;  // looping va

// create the first bob
Create_BOB(&stations[0],0,0,192,144,17,
            BOB_ATTR_VISIBLE | BOB_ATTR_MULTI_ANIM,
            DDSCAPS_SYSTEMMEMORY);

// load animation frames 
for (frame=0; frame <= 16; frame++)
	{
	// load the rocks imagery 
    Pad_Name("OUTART/STATION", "BMP", buffer, frame);
	Load_Bitmap_File(&bitmap8bit, buffer);		

    // load the actual .BMP
    Load_Frame_BOB(&stations[0],&bitmap8bit,frame,0,0,BITMAP_EXTRACT_MODE_ABS);  

    // unload data infile
    Unload_Bitmap_File(&bitmap8bit);

	} // end if

// set state to off
stations[0].state  = STATION_STATE_ALIVE;

// set anim state
stations[0].anim_state = STATION_SHIELDS_ANIM_ON;

// set damage to 0
stations[0].varsI[INDEX_STATION_DAMAGE] = 0;

// set animation rate
Set_Anim_Speed_BOB(&stations[0],15);

// load in the shield on/off animations
Load_Animation_BOB(&stations[0], STATION_SHIELDS_ANIM_ON, 16, shields_on_anim);
Load_Animation_BOB(&stations[0], STATION_SHIELDS_ANIM_OFF, 1, shields_off_anim);

// set animation to on
Set_Animation_BOB(&stations[0], STATION_SHIELDS_ANIM_ON);

// make copies
for (int ship=1; ship < MAX_STATIONS; ship++)
    {
    memcpy(&stations[ship], &stations[0], sizeof(BOB));
    } // end for pulse


    // load the miniature station
    Create_BOB(&stationsmall,0,0,8,8,2,
               BOB_ATTR_VISIBLE | BOB_ATTR_MULTI_FRAME,
               DDSCAPS_SYSTEMMEMORY);

    Load_Bitmap_File(&bitmap8bit, "OUTART/STATIONSMALL8.BMP");		

    // load the actual .BMP
    Load_Frame_BOB(&stationsmall,&bitmap8bit,0,0,0,BITMAP_EXTRACT_MODE_CELL);  
    Load_Frame_BOB(&stationsmall,&bitmap8bit,1,1,0,BITMAP_EXTRACT_MODE_CELL);  

    // unload data infile
    Unload_Bitmap_File(&bitmap8bit);


} // end Init_Stations

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

void Reset_Stations(void)
{
// this function resets all the stations in preparation for another run

for (int index=0; index < MAX_STATIONS; index++)
	{
    // set state to off
    stations[index].state  = STATION_STATE_DEAD;

    // set anim state
    stations[index].anim_state = STATION_SHIELDS_ANIM_ON;

    // set damage to 0
    stations[index].varsI[INDEX_STATION_DAMAGE] = 0;

    } // end for

} // end Reset_Stations

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

void Start_Station(int override=0, int x=0, int y=0)
{
// this functions starts a station, note that if override = 1
// then the function uses the sent data otherwise it's random

// first find an available stations
for (int index=0; index < MAX_STATIONS; index++)
	{
	// is this one dead
	if (stations[index].state  == STATION_STATE_DEAD)
		{
		// position the station

		int xpos = RAND_RANGE((UNIVERSE_MIN_X+256),(UNIVERSE_MAX_X-256));
		int ypos = RAND_RANGE((UNIVERSE_MIN_Y+256),(UNIVERSE_MAX_Y-256));

        // set position
		stations[index].varsI[INDEX_WORLD_X] = xpos;
		stations[index].varsI[INDEX_WORLD_Y] = ypos;

        // start a mine up in the vicinity
        int ang = rand()%16;
		float mine_x = xpos + STATION_RANGE_RING*cos_look16[ang];
		float mine_y = ypos + STATION_RANGE_RING*sin_look16[ang];

        // start a deactivated mine
        Start_Mine(1, mine_x, mine_y, MINE_STATE_AI_SLEEP);    

  	    // set velocity
		stations[index].xv = 0;
		stations[index].yv = 0;

		// set remaining state variables
		stations[index].state  = STATION_STATE_ALIVE;

		// set animation to on
        Set_Animation_BOB(&stations[index], STATION_SHIELDS_ANIM_ON);

		// set anim state
        stations[index].anim_state = STATION_SHIELDS_ANIM_ON;

        // set damage to 0
        stations[index].varsI[INDEX_STATION_DAMAGE] = 0;

		// done so exit
		return;

		} // end if
	
	} // end for index

} // end Start_Station

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

void Move_Stations(void)
{
// this function moves/animates all the stations

for (int index=0; index < MAX_STATIONS; index++)
    {
    // test if station is alive
    if (stations[index].state == STATION_STATE_ALIVE)
        {
        // move the stations
        stations[index].varsI[INDEX_WORLD_X]+=stations[index].xv;
        stations[index].varsI[INDEX_WORLD_Y]+=stations[index].yv;
          
        // test for boundaries
        if (stations[index].varsI[INDEX_WORLD_X] > UNIVERSE_MAX_X)
           {
  		   stations[index].varsI[INDEX_WORLD_X] = UNIVERSE_MIN_X;
           } // end if
		else
		if (stations[index].varsI[INDEX_WORLD_X] < UNIVERSE_MIN_X )
           {
  		   stations[index].varsI[INDEX_WORLD_X] = UNIVERSE_MAX_X;
           } // end if	    

		if (stations[index].varsI[INDEX_WORLD_Y] > UNIVERSE_MAX_Y)
           {
		   stations[index].varsI[INDEX_WORLD_Y] = UNIVERSE_MIN_Y;
           } // end if
		else
		if (stations[index].varsI[INDEX_WORLD_Y] < UNIVERSE_MIN_Y ) 
           {