Mandelbrot Viewer

A performant GUI mandelbrot explorer that enables zooming beyond hardware floating point precision using perturbation theory.

Features

• CPU multiprocessing with jit compilation
• GPU processing via OpenCL (double precision optional)
• Deep zoom capability up to e300 on either CPU or GPU
• GUI for zooming

Examples

Usage

python -m brot 

For command line interface run

python -m brot --help

Repositioning and zooming is performed with the mouse, by clicking and dragging a rectangle around the area you wish to zoom to.

All command line options have equivalent settings in the UI.

Tips

• Increase 'Max Iterations' when the boundary of the mandelbrot set becomes less detailed
• Enable 'high precision' if the image becomes pixelated, this works in CPU and GPU mode
• Enable 'gpu double precision' if the image becomes pixelated in GPU mode. This may be much slower on your GPU
• Render at a lower 'resolution scale' for better performance

Installation

From project root

pip install .

Optionally, if you would like GPU acceleration using OpenCL

pip install .[gpu] 

Note: this will require having an existing OpenCL installation on your system which you can likely get from your graphics card manufacturer.

GMPY2 and PyOpenCL can be a difficult to build on later versions of python on windows, unofficial prebuilt binaries for both can be found here and installed with

pip install path/to/binary.whl

after which you can repeat the original install.

Limitations

• The max iterations must be set manually and increased as you zoom. Ideally this would be automatic.
• The colouring algorithm is relatively simple, and sometimes doesn't give the best looking images. Distance estimation and stripe-average colouring methods could be used to improve the images produced.
• For slow renders there is no user feedback on how the render is progressing. Ideally there would be some feedback in the UI, as well as a more progressive rendering technique which initially renders in low resolutions for faster feedback.
• When computing using perturbations the estimate on when the series approximation becomes innaccurate is sometimes too conservative, missing out on the large performance gains it can provide.
• The GUI experience could be smoother, especially when the renders are fast, by allowing the user to pan and scroll instead of dragging and selecting a rectangle.
• The host memory usage of OpenCL is abnormally high when using a high number of iterations which becomes a serious bottleneck.