' 3D starfield
' made by Svjatoslav Agejenko
' in 2003.03
' H-Page: svjatoslav.eu
' E-Mail: svjatoslav@svjatoslav.eu

DECLARE SUB setstar (x2!, y2!, z2!)
DECLARE SUB galaxy ()
DIM SHARED mitu
DIM SHARED mituv


RANDOMIZE TIMER
mituv = 2000
mitu = mituv
rns = 500
wl = 0

DIM SHARED px(1 TO mitu + 1000)
DIM SHARED py(1 TO mitu + 1000)
DIM SHARED pz(1 TO mitu + 1000)

FOR a = 1 TO mitu
pz(a) = RND * 500 + 20
  n = RND * 100
  px(a) = SIN(n) * 20
  py(a) = COS(n) * 20
NEXT a


SCREEN 13


frm = 10
1
fps = fps + 1
IF tm$ <> TIME$ THEN
'LOCATE 1, 1
'PRINT fps
IF fps > 20 THEN wl = wl + 2 ELSE wl = wl - 1
IF wl < 0 THEN wl = 0
fps = 0
tm$ = TIME$
END IF
frm = frm + 1
xp = SIN(frm / 21) * 3
yp = SIN(frm / 18) * 3

nrk = (3.1412) / 2 + SIN(frm / 35) / 100 + SIN(frm / 21) / 100
rs1 = SIN(nrk)
rc1 = COS(nrk)

FOR a = 1 TO mitu
x = px(a)
y = py(a)
z = pz(a)
x1 = x / z * 160 + 160
y1 = y / z * 100 + 100
PSET (x1, y1), 0

x5 = x * rs1 - y * rc1
y5 = x * rc1 + y * rs1

x = x5
y = y5

z = z - 3
x = x + xp
y = y + yp
IF z < 10 THEN
z = RND * 300 + 400
x = RND * 800 - 400
y = RND * 800 - 400
END IF

x1 = x / z * 160 + 160
y1 = y / z * 100 + 100
c = 3000 / z + 15
IF c > 31 THEN c = 31
PSET (x1, y1), c

px(a) = x
py(a) = y
pz(a) = z
NEXT a


IF mituv - mitu > rns THEN galaxy: rns = RND * 800 + 100

FOR a = 1 TO 2
b = RND * (mitu - 10) + 1
SWAP px(mitu), px(b)
SWAP py(mitu), py(b)
SWAP pz(mitu), pz(b)

x = px(mitu)
y = py(mitu)
z = pz(mitu)
x1 = x / z * 160 + 160
y1 = y / z * 100 + 100
PSET (x1, y1), 0
mitu = mitu - 1
NEXT a

'LOCATE 2, 1
'PRINT wl
FOR a = 0 TO wl
FOR b = 0 TO 1000
c = c / 100
NEXT b
NEXT a

IF INKEY$ <> "" THEN SYSTEM
GOTO 1

SUB galaxy

xf = RND * 4 - 2
yf = RND * 4 - 2
xp = RND * 200 - 100
yp = RND * 200 - 100

FOR a = 1 TO RND * 15 + 10 STEP .04
x = SIN(a) * a * a / 10
y = COS(a) * a * a / 10
setstar x + RND * a * a / 30 + xp, y + RND * a * a / 30 + yp, 700 + RND * a * a / 30 + (x * xf) + (y * yf)
NEXT a

'SOUND 1000, 1
END SUB

SUB setstar (x2, y2, z2)
mitu = mitu + 1
s = mitu

px(s) = x2
py(s) = y2
pz(s) = z2
END SUB