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Introduction
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============
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Calculating Mandelbrot using different ways. It tries to imitate the Mandelbrot
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calculation by Zom-B but be faster in doing so.
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This project started by trying to reproduce this zoom sequence but in higher
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resolution:
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https://en.wikipedia.org/wiki/File:Mandelbrot_sequence_new.gif
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The generator used for this version is available here:
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https://github.com/josch/mandelbrot_zomb
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Overview
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========
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mandel:
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- straight forward "long double" based mandelbrot
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- this is obviously the fastest implementation but has limited precision
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mandel_mpfr:
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- mandelbrot using the arbitrary precision mpfr library
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mandel_quad:
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- mandelbrot using gcc libquad
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mandel_dd:
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- mandelbrot using custom double double math
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- this is the fastest implementation given double double precision
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mandel_dd_aa:
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- with antialiasing
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- it is more than three times faster than the Zom-B version (see below)
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How to compile
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==============
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Compile by running `make`.
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How to execute
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==============
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Each of the tools takes as arguments the width, height, coordinates and
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magnification. Output is in PPM format on standard output.
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$ ./mandel_dd_aa 1920 1080 0.0 0.0 1.0 > out.ppm
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You can compress the ppm by using:
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$ convert out.ppm -format png out.png
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And even compress it further by doing:
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$ optipng -o4 -i0 out.png
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$ advpng -z4 out.png
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= How to generate zoom animation =
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The shell script (with a small python helper) `run.sh` will generate and
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execute a list of commands to create a zooming sequence of images.
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You can create a video of the resulting sequence using:
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$ avconv -i out_%05d.png out.mp4
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Or a gif animation by using:
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$ convert -delay 20 -loop 0 out_*.png out.gif
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Benchmark
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=========
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Benchmark against mandelbrot computation by Zom-B:
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at zoom coordinates:
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- x = -0.743643887037158704752191506114774
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- y = 0.131825904205311970493132056385139
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1 to 1e32 in 100 steps at 320x240 and no AA took
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- mandel_dd 1:28 h
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- mandel_zomb 2:45 h
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1.0e17 at 1920x1080 with 5xAA took
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- mandel_dd_aa 2:38 h
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- mandel_zomb 8:40 h
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