Random Art in Nim (& OpenGL)

The official repo can be found on GitLab: https://gitlab.com/define-private-public/random-art-Nim

Though there is a mirror on GitHub were issues can be addressed: https://github.com/define-private-public/random-art-Nim

What is this?

This is an implementation of random art in the Nim programming language. You can give it an equation (or have it generate one) and it will spit out an image. This can do rendering on the CPU (normally) or on the GPU using OpenGL (ES 3.0). It is also built using GLFW (v3) and stb_image.

It is based off of the Python example found here: http://math.andrej.com/2010/04/21/random-art-in-python/

Building

From the root directory, run nake release. Make sure you have the necesssary packages and libraries specified in random_art.nimble.

Usage

If you want a simple 256x256 randomly generated piece of art rendered on the CPU, simply run ./random_art and sit back. An equation will pop out on standard output and it will be saved to render.png.

Here are some more details from running ./random_art help:

Usage:
  ./random_art [input] [options..]

  input : a path to an equation file, or provide `stdin` to read input
          from standard input

  Options:
  -r, --renderer : cpu | opengl
                   render on the CPU or with a GPU (using OpenGL)
  -s, --size     : <width>x<height>
                   the dimension of the render, must be a positive int
  -b, --bounds   : <xMin>,<xMax>,<yMin>,<yMax>
                   the bounds to use to render, must be a float
  -o, --output   : <filename>.png
                   the file to save the render as, must end with .png

If you render using the -r:opengl flag, please note that a window will pop up very quickly and then close. Rending with OpenGL is much faster, but note that the images might appear a little different than if rendered by the CPU. Take a look below; the first is rendered on the CPU, where the second is on the GPU.

Though it looks pretty close, so it might not matter too much. :P

Examples

If you want get the image that is at the top of this README, that equation is stored in examples/complex.txt, and run with the command:

./random_art examples/complex.txt -s:960x540 -b:-0.5,0.5,-1,1

Here's a much simplier example from examples/simple.txt:

(mul
  (var y)
  (mod
    (sum
      (var x)
      (var y)
    )
    (const 1 0.7 -0.1 0.95)
  )
)

It produces this:

Known Issues

• When saving renders with -r:opengl there is an issue if you try to do a render that is larger than you screen size. Go ahead and try it. It probably has something to do with glReadPixels()
• There is also some really odd bug when reading in equations directly from standard input. If an equation is really long, it will turn some parts into (zero) expressions. Reading in from files though is completely fine.

License

This port is under the MIT license. See the file LICENSE.txt for details.