opengl-fractal

This is my OpenGL fractal explorer program. It was developed for the Rasberry Pi 4B (OpenGL ES 3.1) to put into a coffee table, but it can perfectly well be used on a desktop or laptop. It is controlled via the keyboard, with a Python script to map rotary encoders to keyboard keys.

Run:

This repo contains precompiled binaries for Windows 10 and Raspberry Pi OS, which should (hopefully) work. The binaries are in opengl-fractal/opengl-fractal. If you get a .dll error on Windows, you may need to install the latest Visual C++ Redistributable

Build:

Windows:

If you have some flavor of Microsoft Visual Studio 2019, go to File -> Open -> Cmake... and open the CMakeLists.txt in the root directory of the project. Choose x64-Debug or x64-Release in the Configuration dropdown and fractal.exe in the Startup Item dropdown and compile.

Raspberry Pi 4/Linux:

Run the following commands in the project root directory:
$ cmake . -DCMAKE_BUILD_TYPE=Release/Debug
$ make fractal

Fractal binary will be written to opengl-fractal/opengl-fractal

To run the Python script (on a Pi):

sudo pip3 install python-uinput
sudo modprobe uinput
sudo python3 (install folder)/opengl-fractal/opengl-fractal/src/rotaryencoder.py

Controls:

UP DOWN LEFT RIGHT move the crosshair around
W A S D move the crosshair around just like the arrow keys in Mandelbrot mode. In Julia set mode, they move the crosshair on the Mandelbrot set, which changes the set displayed
Enter zooms in
Backspace zooms out
J displays the Julia set pointed to by the crosshair in-place -- i.e., The Z value is the same as the C value from the Mandelbrot set and the zoom level is maintained
H displays the whole Julia set for the point at the crosshair -- the view is set to the origin (0 + 0i) and a zoom level of 1. Pressing H again always returns you to where you were when you first pressed it, even if you change the Julia set. J will return you back to the Mandelbrot in-place.

Mandelbrot	`J`	`H`

N and P respectively raise and lower the exponent of the fractal function by an interval specified by . (+- .01, .05, .25, or 1.0)

`N`	-	`P`
z ↦ z^4.10 + c	z ↦ z^2 + c (Mandelbrot)	z ↦ z^1.90 + c

R resets to 1x zoom and the origin (0 + 0i) on any set
C centers the screen at the crosshair
O toggles through different maximum iterations (100, 200, or 400 -- default 400)
I toggles the text info on/off
T toggles displaying the render time for the last frame (for diagnostics)
Alt + Space toggles between windowed and fullscreen mode
Esc exits the program

There's lots to explore, have fun!