DECLARE SUB pal ()
DECLARE SUB branch (x, y, length, angle)

' Hoppy's Recursive L-system fractaly stuff
' vertical is 0 degrees ^
' animated method, using sine generated values, but with a constant
' divider, per branch (aa, ra, da)

pi = ATN(1) * 4
CLS
DIM SHARED br%, ord%, a&
a& = 1

INPUT "# branches (min 1)"; br%
INPUT "Seed"; t&
INPUT "# orders"; ko%

DIM SHARED angle(br%), ratio(br%), di(br%), o%, ps
RANDOMIZE t&
FOR n% = 1 TO br%
    aa(n%) = 50 + RND * 50
    ra(n%) = 50 + RND * 50
    da(n%) = 50 + RND * 50
NEXT n%

SCREEN 12
pal
here:
    ord% = 0
    o% = ko%
    ps = 14 / o%
    LINE (320, 420)-(320, 320), 1
    FOR n% = 1 TO br%
        angle(n%) = pi * SIN(b& / aa(n%))
        ratio(n%) = .5 + SIN(b& / ra(n%)) * .4
        di(n%) = .5 + SIN(b& / da(n%)) * .4
        LOCATE n% + 2, 1: PRINT INT(180 / pi * angle(n%))
        LOCATE n% + 2, 10: PRINT ratio(n%)
        LOCATE n% + 2, 19: PRINT di(n%)
    NEXT n%
   
    COLOR 14: LOCATE 1, 1: PRINT "Hoppy's funky l-system trees"
    COLOR 15
    LOCATE 2, 1: PRINT " Angles   "; " Ratios  "; " Diminuations"
    LOCATE br% + 3, 1: PRINT "Counter:"; b&
    LOCATE br% + 4, 1: PRINT "Orders:"; ko%; "Branches:"; br%; "Random seed:"; t&
    LOCATE br% + 5, 1: PRINT "Keys:"
    LOCATE br% + 6, 1: PRINT "7/1 -> +/- 1"
    LOCATE br% + 7, 1: PRINT "8/2 -> +/- 10"
    LOCATE br% + 8, 1: PRINT "9/3 -> +/- 100"
   
    branch 320, 420, 100, 0
    DO
        i$ = INKEY$
    LOOP WHILE i$ = ""
    CLS
    IF i$ = "7" THEN b& = b& + 1
    IF i$ = "1" THEN b& = b& - 1
    IF i$ = "8" THEN b& = b& + 10
    IF i$ = "2" THEN b& = b& - 10
    IF i$ = "9" THEN b& = b& + 100
    IF i$ = "3" THEN b& = b& - 100
    IF i$ = CHR$(27) THEN END

GOTO here

SUB branch (x, y, length, angle)
ord% = ord% + 1: IF ord% > o% THEN EXIT SUB
FOR n% = 1 TO br%
        xstart = x + length * ratio(n%) * SIN(angle)
        ystart = y - length * ratio(n%) * COS(angle)
        newangle = angle + angle(n%)
        newlength = length * di(n%)
        xend = xstart + newlength * SIN(newangle)
        yend = ystart - newlength * COS(newangle)
        LINE (xstart, ystart)-(xend, yend), ord% * ps:  a& = a& + 1
        IF ord% = o% THEN PSET (xend, yend), 15
        branch xstart, ystart, newlength, newangle
ord% = ord% - 1
NEXT n%
'Whooops: Not needed!
'branch xstart, ystart, newlength, newangle
'ord% = ord% - 1
END SUB

SUB pal
FOR p% = 1 TO 15
PALETTE p%, p% * 4 * 256 + 37 - (p% * 2) + p% * 65536 * (p% \ 6)
PALETTE 15, 60 + 30 * 256 + 55 * 65536
LINE (p% * 4, 470)-(p% * 4 + 4, 480), p%, BF
NEXT p%

END SUB