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[red_Marvin]

Surprise!
Maybe not to some, since an older version has been visible on freebasic.net forums, but I though you migh be interested here too.

Code:

' random/changing IFS fractal generator by red_Marvin/insomninja code is licensed under the GNU GPL

#define fc 6.283185308

declare sub ifs(x0 as single, y0 as single, branchcount as uinteger, l0 as single, a0 as single, lm as single ptr, am as single ptr, maxdepth as integer, depth as uinteger = 0)

randomize timer
dim as uinteger md = 10
dim as uinteger bc = 3
dim as single ptr lm = callocate(len(single)*bc)
dim as single ptr am = callocate(len(single)*bc)
dim as single ptr lma = callocate(len(single)*bc)
dim as single ptr ama = callocate(len(single)*bc)

dim as single a0=rnd*fc
for n as integer = 0 to bc-1
    lma[n]=rnd*.2+.8
    ama[n]=(rnd-rnd)/100
    lm[n]=rnd
    am[n]=rnd*fc
next

screenres 1024,768,32,1,&H41
setmouse,,0
do
    screenlock
    cls
    ifs(512, 384, bc, 100, a0, lm, am, md)
    screenunlock
    for n as integer = 0 to bc-1
        lma[n]*=rnd/500+.999
        if lma[n]>1.01 then lma[n]=1.01
        if lma[n]<.99 then lma[n]=.99
        lm[n]*=lma[n]
        if lm[n]>.9 then lm[n]=.9 : lma[n]=1
        if lm[n]<.5 then lm[n]=.5 : lma[n]=1
        
        ama[n]+=(rnd-rnd)/1000
        if ama[n]>.01 then ama[n]=.01
        if ama[n]<-.01 then ama[n]=-.01
        am[n]+=ama[n]
        if am[n]>fc then am[n]-=fc
        if am[n]<0 then am[n]+=fc
    next
    sleep 15
loop while inkey=""
deallocate lm
deallocate am
deallocate lma
deallocate ama

sub ifs(x0 as single, y0 as single, branchcount as uinteger, l0 as single, a0 as single, lm as single ptr, am as single ptr, maxdepth as integer, depth as uinteger = 0)
    if depth < maxdepth then
        dim as single l1, a1, x1, y1
        for n as uinteger = 0 to branchcount-1
            l1=l0*lm[n]
            a1=a0+am[n]
            x1=x0+l1*cos(a1)
            y1=y0+l1*sin(a1)
            line(x0, y0)-(x1, y1), rgba(255,255,255,64-depth*64\maxdepth)
            ifs(x1, y1, branchcount, l1, a1, lm, am, maxdepth, depth+1)
        next
    end if
end sub