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3080 :: Mandelbrot fraktal with SDL2 produces artifacts at high zoom levels

• Bernd (orginal) [2017-07-30T13:00:46+02:00] view original

  Hei There!

  I am playing with nim and SDL2 and have been hacking together a Mandelbrot generator. Consider that I am not a C type programmer, my knowledge with programming is based on html, php, mysql and some js.

  Here is a GIF showing the artifacts: https://media.giphy.com/media/3o6vXPxFdXDzmYhMTS/giphy.gif

  And here you can download the source for compiling: https://www.file-upload.net/download-12633332/AnoraksMandelbrot.zip.html

  There are some basic controls:

  • Arrow keys for navigating
  • Z and X for zooming in and out
  • I and O for iterating

  Any clue what is happening there? Is this a limitation of SDL or nim; or did i do something wrong? :D

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• def (orginal) [2017-07-30T14:03:38+02:00] view original

  Very highly magnified images require more than the standard 64–128 or so bits of precision that most hardware floating-point units provide, requiring renderers to use slow "bignum" or "arbitrary-precision" math libraries to calculate.

  https://en.wikipedia.org/wiki/Mandelbrot_set#Perturbation_theory_and_series_approximation

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• Bernd (orginal) [2017-07-30T14:57:19+02:00] view original

  +1

  Thanks for this hint! I was thinking alreading that the precision might be a problem. But this explains it in good detail. :)

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• Bernd (orginal) [2017-07-30T16:17:50+02:00] view original

  Well, the bignum / gmp packages do not install.

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