DECLARE SUB pal ()
CLS : SCREEN 13
pal





DIM x%(3), y%(3), c%(1)
xshift% = 190: '>+
yshift% = 100: '^-     

recen = 0:  ' centre X
imcen = 0: ' centre Y these coords x,y MUST be inside the M set, for -k its
s = .02: ' some sort of scale, small=zoomed in
k% = 2: '- number of its for this boundry, starts at 2
c%(1) = 1

CLS : c% = 2
FOR k% = 2 TO -20 STEP -1
c%(0) = c%(1)
c%(1) = c%(1) + 2: IF c%(1) = 192 THEN c%(1) = 1
PAINT (xshift%, yshift%), c%(0), c%(0)

FOR i% = 0 TO 10000
rec = s * i% + recen: imc = imcen
GOSUB 500
IF outside% = 1 GOTO 100: ' if hit boundry
NEXT i%
END

100 vin% = 1: vout% = 2: vnew% = 3
x%(vin%) = i% - 1: x%(vout%) = i%: x%(vnew%) = i%
y%(vin%) = 0: y%(vout%) = 0: y%(vnew%) = 1
xin% = x%(vin%): yin% = y%(vin%): xout% = x%(vout%): yout% = y%(vout%)
PSET (x%(vin%) + xshift%, y%(vin%) + yshift%), c%(1)

200 rec = s * x%(vnew%) + recen: imc = s * y%(vnew%) + imcen
GOSUB 500
IF outside% = 1 GOTO 300
LINE -(x%(vnew%) + xshift%, -y%(vnew%) + yshift%), c%(1)
vref% = vin%: vin% = vnew%: vnew% = vref%
GOTO 400

300 vref% = vout%: vout% = vnew%: vnew% = vref%

400 x%(vnew%) = x%(vin%) + x%(vout%) - x%(vref%)
y%(vnew%) = y%(vin%) + y%(vout%) - y%(vref%)
IF x%(vin%) <> xin% OR y%(vin%) <> yin% GOTO 200
IF x%(vout%) <> xout% OR y%(vout%) <> yout% GOTO 200
NEXT k%
END

500 outside% = 1:    'This is where the point is calculated
re = rec: im = imc
FOR j% = 0 TO 2 - k%
re2 = re * re: im2 = im * im
im = 2 * re * im + imc
re = re2 - im2 + rec
IF re * re + im * im > 4 THEN RETURN
NEXT j%
outside% = 0
RETURN

SUB pal

FOR t% = 0 TO 192
LINE (t%, 195)-(t%, 199), t%
NEXT t%

FOR p = 0 TO 63 STEP 2
p% = p
a% = a% + 1
PALETTE a%, 63 + 256 * p%
NEXT p
FOR p = 0 TO 63 STEP 2
p% = p
a% = a% + 1
PALETTE a%, 63 - p% + 63 * 256
NEXT p
FOR p = 0 TO 63 STEP 2
p% = p
a% = a% + 1
PALETTE a%, 256 * 63 + p% * 65536
NEXT p
FOR p = 0 TO 63 STEP 2
p% = p
a% = a% + 1
PALETTE a%, (63 - p%) * 256 + 63 * 65536
NEXT p
FOR p = 0 TO 63 STEP 2
p% = p
a% = a% + 1
PALETTE a%, p% + 65536 * 63
NEXT p
FOR p = 0 TO 63 STEP 2
p% = p
a% = a% + 1
PALETTE a%, (63 - p%) * 65536 + 63
NEXT p


END SUB