Frozen Fractals is a free program which creates snowflake fractals based on replacement of a straight line with a more complex figure. It consists of a fractal interpreter and a user interface, both of which can be downloaded here:
It is possible to use the fractal interpreter without the user interface, but the user interface requires the interpreter. Running these programs requires Python, which is available for all major platforms. Python 2 is required for the moment, rather than Python 3.
Fractals are expressed using a simple fractal description language. Here are some examples.
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