Forum archive

Ken: your version of the mandelbrot set in QBasic.

Return to forum index

• Madman at 2005-10-30 02:25
  Hello again, Ken: --
  
  What would your suggestion of the mandelbrot set algorithm be when devised entirely in QBasic?
  
  Thanks in advance :)
• Awesoken at 2005-10-30 02:57
  It would be very similar to the MANDEL.KC script I wrote for EVALDRAW:
  
  

  SCREEN 12
  
  FOR sy% = 0 TO 479
  
     FOR sx% = 0 TO 639
  
        x = (sx% - 320) / 160: ox = x
  
        y = (sy% - 240) / 160: oy = y
  
        FOR c% = 15 TO 1 STEP -1
  
           xx = x * x: yy = y * y
  
           IF xx + yy >= 4 THEN EXIT FOR
  
           y = x * y * 2 + oy
  
           x = xx - yy + ox
  
        NEXT
  
        PSET (sx%, sy%), c%
  
     NEXT
  
  NEXT

  
  
  If you were looking for fancy optimizations, you won't find them here. If I really cared, I would write the algorithm in assembly code, first using SSE (because it's easier), and then MMX - could be nearly twice the speed of SSE, although I don't know if the precision would be acceptable - I can't say for sure until trying. Of course, taking advantage of multithreading is a must. MANDEL.KC already does this since Evaldraw can take full advantage of HT/Dual core processors.