' Svjatoslav Agejenko
' year 1999

DECLARE SUB setpal ()
DEFINT A-Y
DECLARE SUB box (x1, y1, x2, y2, x3, y3, x4, y4, c) 'draw filled
                                                    'box using 4 cordinates
                                                 '(sometimes don't work
                                                 'correctly, but fast.
                                                 '(PAINT command used))
DIM SHARED x1(1 TO 40, 1 TO 40)  ' X & Y  cordinates
DIM SHARED y1(1 TO 40, 1 TO 40)  '

SCREEN 12

setpal
zfa = 1.5
1
FOR b = 1 TO 40
FOR a = 1 TO 40

x = 120 + (a * 10)
y = 200 + (b * 3)

y = y - COS(SQR((a - 20) ^ 2 + (b - 20) ^ 2) / zfa) * 20

x = (x - 320) * (b + 50) / 50 + 320
y = (y - 240) * (b + 50) / 50 + 240

x1(a, b) = x
y1(a, b) = y

NEXT a
NEXT b



FOR b = 1 TO 39
FOR a = 1 TO 39
IF (a + b) \ 2 = (a + b + 1) \ 2 THEN c = 0 ELSE c = 5
kz = b + (a / 3)

box x1(a, b), y1(a, b), x1(a + 1, b), y1(a + 1, b), x1(a, b + 1), y1(a, b + 1), x1(a + 1, b + 1), y1(a + 1, b + 1), c
NEXT a
NEXT b

a$ = INPUT$(1)
zfa = zfa * 1.9
CLS
IF zfa > 10 THEN SYSTEM
GOTO 1

SUB box (x1, y1, x2, y2, x3, y3, x4, y4, c1)

c1 = c1 + (y2 - y1) / 3.5 + (kz / 8) + 4

IF c1 < 0 THEN c1 = 0
IF c1 > 15 THEN c1 = 15

a = SQR((x1 - x2) ^ 2 + (y1 - y2) ^ 2)
b = SQR((x3 - x4) ^ 2 + (y3 - y4) ^ 2)
IF b < a THEN b = a
FOR a = 1 TO b
x5 = (x2 - x1) * a / b + x1
y5 = (y2 - y1) * a / b + y1
x6 = (x4 - x3) * a / b + x3
y6 = (y4 - y3) * a / b + y3
LINE (x5, y5)-(x6, y6), c1
LINE (x5 + 1, y5)-(x6 + 1, y6), c1
NEXT a
END SUB

SUB setpal
FOR a = 0 TO 16
OUT &H3C8, a
OUT &H3C9, a * 4
OUT &H3C9, a * 4
OUT &H3C9, a * 3
NEXT
END SUB