§ Программа на QBasic

1SCREEN 13
2
3DIM SHARED wp(320) AS SINGLE
4DIM SHARED wn(320) AS SINGLE
5DIM SHARED bt(320) AS INTEGER
6
7' Empty
8FOR i = 0 TO 319: wp(i) = 0: NEXT
9
10Atmo
11
12DO
13
14  k$ = INKEY$
15
16  ' Water effect
17  IF k$ = " " OR id > nx THEN
18
19    FOR i = 0 TO 4
20      x = INT(RND * 320)
21      wp(x) = wp(x) - 8 * RND
22    NEXT
23
24    id = 0
25    nx = INT(RND * 25 + 15)
26
27  END IF
28
29  ' Redraw
30  Update
31
32  ' Time effect
33  id = id + 1
34LOOP UNTIL k$ = CHR$(27)
35
36SUB Atmo
37
38  RANDOMIZE TIMER
39
40  LINE (0, 0)-(320, 100), 1, BF
41  CIRCLE (300, 20), 13, 14: PAINT (300, 20), 14
42
43  ' Beach level
44  FOR x = 0 TO 320: bt(x) = 200: NEXT
45
46  ' Draw simple beach
47  FOR x = 0 TO 128
48    h = INT(x ^ 2 / 128)
49    s = 150 + h
50    bt(x) = s
51    FOR y = s TO 199
52      l = y - 149
53      IF RND > l / 75 THEN cl = 14 ELSE cl = 6
54      PSET (x, y), cl
55    NEXT
56  NEXT
57
58END SUB
59
60SUB Update
61
62  omega = .995
63  relax = .995
64
65  FOR i = 0 TO 319
66
67    IF i = 0 THEN a = wn(1) ELSE a = wn(i - 1)
68    IF i = 319 THEN b = wn(318) ELSE b = wn(i + 1)
69
70    laplas = (a + b) / 2
71
72    ' Difference between previous (wn) and current (wp) level
73    wp(i) = laplas + omega * (wn(i) - wp(i))
74
75    ' Relax
76    wp(i) = wp(i) * relax
77
78  NEXT
79
80  ' Line level
81  WU = 100
82  WL = 170
83
84  ' Swap fields
85  FOR i = 0 TO 319
86
87    SWAP wp(i), wn(i)
88
89    lv = WL - INT(wn(i))
90
91    ' Draw
92    IF lv <= bt(i) THEN
93
94      LINE (i, WU)-(i, lv - 2), 1   ' Sky
95      LINE (i, lv)-(i, bt(i)), 3    ' Water
96
97      ' Lighting
98      nx = wn(i + 1) - wn(i)
99      IF nx < 0 THEN cl = 15 ELSE cl = 11
100      PSET (i, lv - 1), cl
101
102    ELSE
103
104      LINE (i, WU)-(i, bt(i)), 1' Sky
105
106    END IF
107
108  NEXT
109
110END SUB