// Mandelbrot
//
HGR 
PROC mandel
print time / 1000
savescreen ("mandel.bmp") 
END 
//
DEF PROC mandel
LOCAL mColour, cCounter
mColour = 16
LOCAL lSide, tp
lSide = -2.0
tp = 1.25
LOCAL xSide, ySide
xSide = 2.5
ySide = -2.5
LOCAL xScale, yScale, oMax
xScale = xSide / GWIDTH
yScale = ySide / GHEIGHT
LOCAL x, y
LOCAL cx, cy, zx, zy, tempx
FOR y = 0 TO GHEIGHT / 2 CYCLE 
  FOR x = 0 TO GWIDTH - 1 CYCLE 
    cx = x * xScale + lSide
    cy = y * yScale + tp
    zx = 0
    zy = 0
    cCounter = 0
    oMax = 15
    WHILE (((zx * zx + zy * zy) < oMax) & (cCounter < mColour)) CYCLE 
      tempx = zx * zx - zy * zy + cx
      zy = 2 * zx * zy + cy
      zx = tempx
      cCounter = cCounter + 1
    REPEAT 
    COLOUR = cCounter
    PLOT (x, y)
    PLOT (x, GHEIGHT - 1 - y)
  REPEAT 
REPEAT 
UPDATE 
ENDPROC