'''
''' playfield tutorial - part 7
''' sprite sharing
'''
''' by greg smith
'''

'''
''' use c coordinates
'''
OPTION C_COORDS

'''
''' turn off escape processing for speed
'''
OPTION ESCAPE OFF

'''
''' turn off automatic graphics show
'''
OPTION SHOW OFF

dim x as int  'position of lemming from 0-480
dim y as int  'position of lemming from 0-300
dim z_dir as int  'which direction of lemming
dim z_cnt as int  'animation image of lemming

dim sprite_field as int 'the sprite number of the playfield sprites
dim sprite_lemming as int   'the sprite number of the lemming sprites
dim lemming_left as int     'index into lemming sprite for going left
dim lemming_right as int    'index into lemming sprite for going right
dim lemming_up as int       'index into lemming sprite for going up
dim lemming_down as int     'index into lemming sprite for going down

dim collision_street as char     'the street's collision value
dim collision_pf0 as char        'playfield 0
dim collision_pf9 as char        'playfield 9

dim collision_table[30,31] as char 'the collision table

dim obj_ctr as int        'the next object to be allocated
dim current_playfield as int 'the current playfield onscreen
dim current_screen as int
dim points as long           'your score
dim n_playfields as int      'the number of playfields
dim current_sprite as int    'the number of loaded sprites

type obj                     'the sprite object
    mysprite as int          'my sprite number
    x as int                 'x coord on screen (0-159)
    y as int                 'y coord on screen (0-99)
    playfield as int         'playfield this sprite belongs on
    screen as int            'screen within playfield (0-9)
    amt as int               'points for catching this sprite
    sound[32] as char        'the sound to make
end type

dim objs[40] as obj        'all the sprites
dim sprite_names[30,32] as char ' sprite names

'''
''' update file - copy file from app to flash
'''
sub update_file(fname[] as char)
    inline File_remove(fname);
    inline _load(fname);
end sub

'''
''' initialization
'''
sub init
    update_file("playfield1.dat") 'get the .dat file into flash
    update_file("playfield2.dat")

    sprite_field = 0       'playfield sprite
    sprite_lemming = 31    'lemming sprite is largest possible sprite - on top

    lemming_left=0        'lemming left image
    lemming_right=5       'lemming right image
    lemming_up=10         'lemming up image
    lemming_down=15       'lemming down image

    '''
    ''' the lemming has 20 bitmaps 5 for each direction
    sprite sprite_lemming, "lemming.pic"

    '''
    ''' the lemming can be anywhere on the playfield from
    ''' x = 0-480
    ''' y = 0-300
    x=240  'center of the playfield
    y=150  'center of the playfield
    z_dir=lemming_right  ' lemming faces right
    z_cnt=0              ' animation counter

    '''
    ''' set the collision flags
    '''
    collision_street = \x\
    collision_pf0 = \0\
    collision_pf9 = \9\

    obj_ctr=0    'initialize the object counter
    points = 0      'reset points

    n_playfields = 2   'maximum number of playfields
    current_sprite = 1 'the next sprite number available

    obj_init_all    'init all objects

end sub

sub repaint
    dim field_x as int   '0,1,2 for the horizontal bitmap
    dim field_y as int   '0,1,2 for the vertical bitmap
    dim lemming_x as int     '0-159 for the x coord on the screen
    dim lemming_y as int     '0-99  for the y coord on the screen
    dim obj_x as int        ' position of the object
    dim obj_y as int        ' position of the object
    dim obj_field_x as int
    dim obj_field_y as int
    dim obj_field as int
    dim i as int

    field_x = x / 160    ' compute the horizontal bitmap
    field_y = y / 100    ' compute the vertical bitmap
    current_screen = field_y*3 + field_x ' combine them to compute the bitmap number

    lemming_x = x mod 160  ' compute the lemming's position on the screen
    lemming_y = y mod 100  ' compute the lemming's position on the screen

    move sprite_field, 0, 0, current_screen 'display the current field
    redraw sprite_field

    paper white  'transparent color for the lemming
    ink ltgrey

    '''
    ''' iterate across all sprites and display
    '''
    for i=0 to obj_ctr-1
        '''
        ''' if the sprite is on the current playfield
        ''' and the sprite is not hidden (x=-1) then
        ''' if the sprite is on the current screen then display it
        '''
        if objs[i].playfield=current_playfield and objs[i].x >= 0 then
            if objs[i].screen = current_screen then ' is the sprite on-screen?
                move objs[i].mysprite, objs[i].x, objs[i].y
                redraw objs[i].mysprite
             endif
        endif
    next 'i

    '''
    ''' display points
    '''
    ink white
    font "mini_bold_font"
    printxy 0,0,points

    move sprite_lemming, lemming_x, lemming_y, z_dir+z_cnt 'display the lemming 
    redraw sprite_lemming

    redraw show        'redraw all the sprites
end sub

'''
''' increment the z_cnt variable
'''
sub update_z_cnt
    z_cnt=(z_cnt+1) MOD 5
end sub

'''
''' check for collision against table
'''
function collision_check(x as int, y as int) as char
    collision_check = collision_table[y/10,x/16]
end function

'''
''' transport lemming to another playfield
'''
sub transport(f as int)
    init_playfield(f)
    if f=1 then
        x=240
        y=150
    elseif f=2 then
        x=230
        y=150
    endif
end sub

'''
''' process the keyboard
'''
sub get_keys
    dim tmp as int
    dim cc as int

    if key(#KEY_UP) then   'move the lemming up
        tmp=y-3
        cc = collision_check(x,tmp)
        if cc = collision_street then
            y=tmp
            z_dir=lemming_up
            update_z_cnt
        end if
        if cc >= collision_pf0 and cc <= collision_pf9 then
            transport(cc-collision_pf0)
        end if
    end if
    if key(#KEY_DOWN) then 'move the lemming down
        tmp=y+3
        cc = collision_check(x,tmp)
        if cc = collision_street then
            y=tmp
            z_dir=lemming_down
            update_z_cnt
        end if
        if cc >= collision_pf0 and cc <= collision_pf9 then
            transport(cc-collision_pf0)
        end if
    end if
    if key(#KEY_LEFT) then 'move the lemming left
        tmp=x-3
        cc = collision_check(tmp,y)
        if cc = collision_street then
            x=tmp
            z_dir=lemming_left
            update_z_cnt
        end if
        if cc >= collision_pf0 and cc <= collision_pf9 then
            transport(cc-collision_pf0)
        end if
    end if
    if key(#KEY_RIGHT) then 'move the lemming right
        tmp=x+3
        cc = collision_check(tmp,y)
        if cc = collision_street then
            x=tmp
            z_dir=lemming_right
            update_z_cnt
        end if
        if cc >= collision_pf0 and cc <= collision_pf9 then
            transport(cc-collision_pf0)
        end if
    end if
end sub

'''
''' get a string from the file
''' a string ends in CR/LF
'''
sub getstring(f as int, s[] as char)
    dim x as char
    dim n as int

    n=0

    while(true)
        get f,,x
        if x<>13 then
            if x=10 then exit while
            s[n] = x
            s[n+1] = 0
            n=n+1
        endif
    wend
end sub

'''
''' load_sprite will find a previously loaded sprite and return its
''' sprite number or load the sprite and add its name to the list
''' and return the new sprites index
'''
function load_sprite(name[] as char) as int
    dim found as int
    found = false
    for i=0 to current_sprite-1
        if name = sprite_names[i] then
            found = true
            load_sprite = i+1
            exit for
        end if
    next 'i
    if not found then
        load_sprite = current_sprite
        sprite current_sprite, name
        sprite_names[current_sprite-1]=name
        current_sprite = current_sprite + 1
    end if
end function

'''
''' obj_init will allocate a single object and attach it to a sprite
'''
sub obj_init(pfld as int, fname[] as char, x as int, y as int, amt as int, sound[] as char)
    objs[obj_ctr].playfield = pfld
    objs[obj_ctr].x = x mod 160
    objs[obj_ctr].y = y mod 100
    objs[obj_ctr].screen = (x/160)+(y/100)*3
    objs[obj_ctr].mysprite = load_sprite(fname)
    objs[obj_ctr].amt = amt
    objs[obj_ctr].sound = sound
'   sprite command deleted
'   move obj_ctr, 160, 100 'hide sprite
    obj_ctr = obj_ctr+1
end sub

'''
''' init all objects
'''
sub obj_init_all

    print "Loading Sprites..."

    obj_init(0, "money.pic", 32,50,100, "money.mus")
    obj_init(0, "money.pic", 20,140,100, "money.mus")
    obj_init(0, "money.pic", 20,240,100, "money.mus")
    obj_init(0, "money.pic", 224,40,100, "money.mus")
    obj_init(0, "money.pic", 224,140,100, "money.mus")
    obj_init(0, "money.pic", 224,240,100, "money.mus")
    obj_init(0, "money.pic", 432,40,100, "money.mus")
    obj_init(0, "money.pic", 432,110,100, "money.mus")
    obj_init(0, "money.pic", 432,170,100, "money.mus")
    obj_init(0, "money.pic", 432,240,100, "money.mus")

    print "Still Loading Sprites..."

    obj_init(1, "money.pic", 64, 40, 100, "money.mus")
    obj_init(1, "money.pic", 64,140, 100, "money.mus")
    obj_init(1, "money.pic", 64,260, 100, "money.mus")
    obj_init(1, "money.pic",224, 40, 100, "money.mus")
    obj_init(1, "money.pic",224,140, 100, "money.mus")
    obj_init(1, "money.pic",224,260, 100, "money.mus")
    obj_init(1, "money.pic",384, 40, 100, "money.mus")
    obj_init(1, "money.pic",384,140, 100, "money.mus")
    obj_init(1, "money.pic",384,260, 100, "money.mus")
end sub

'''
''' read the playfield file defined by
''' 'field' and set up the sprites and
''' the collision table
'''
sub init_playfield(field as int)
    dim fname[32] as char
    dim s[32] as char

    current_playfield = field-1

    ''' create the filename to read
    sprint fname, "playfield", field, ".dat"

    ''' open the playfield definition file
    open fname for read as 1

    getstring(1, s) 'get the sprite name

    '''
    ''' the playfield sprite has 9 bitmaps
    ''' one for each of the different areas of the
    ''' playfield
    sprite sprite_field, s

    '''
    ''' read the 30 playfield collision rows
    '''
    for i=0 to 29
        getstring(1, collision_table[i])
    next

    '''
    ''' close the playfield.dat file
    '''
    close 1
end sub

'''
''' check collisions
'''
sub check_collisions
    for i=0 to obj_ctr-1
      if objs[i].playfield = current_playfield and objs[i].screen = current_screen and objs[i].x>=0 then
        move objs[i].mysprite, objs[i].x, objs[i].y
        if collision(sprite_lemming, objs[i].mysprite) then
            objs[i].x=-1 ' turn off this sprite
            points = points + objs[i].amt
            music foreground, objs[i].sound
            music foreground, play
            exit for
        end if
      endif
    next
end sub

'''
''' main subroutine
'''
sub mainsub
    init
    init_playfield(1)

    while true
        inline _escape(0); /* check the escape key */
        repaint
        get_keys
        check_collisions
    wend
end sub

'''
''' call the main subroutine
'''
mainsub