Fractal Generator Library

This project consists of:

• An API to request the generation of a fractal descriptor given a fractal pattern and the number of recursions.
• A main framework (which expects concrete transformations implementations) to compute fractals from an specific fractal pattern implementation.
• A SPI to implement fractal patterns of any kind and a particular one to implement geometric kind of fractal patterns
• A specific fractal pattern implementation consisting of shape transformations for the simplest of all shapes: lines!
• A sub-framework to update progress of an abstract task (i.e. fractal generator) using abstract workers.
• Two implementations of the update progress workers: polling (asynchronous) and threshold reached (synchronous).

Usage Examples

The following client applications have been developed using this library:

• Android App
• Java Swing App
• JavaFX App

Usage & Design

The generator framework requires concrete implementations of the shapes is going to be using with their respective transformation logic:

	public interface GeometricPattern<SHAPE_TYPE> {
		public void computeConstants(SHAPE_TYPE base);
		public SHAPE_TYPE computeGeometryEquivalentTo(SHAPE_TYPE relativeBase);
	}

Having this interface implemented, the framework will generate the fractal using the following logic:

• The first shape of a fractal pattern is a base, and the rest of the shapes are relative transformations to be applied to said base.
• The generator recursively applies the same transformations to each of the other shapes.
• Cut off arguments are available to catalyze the process. The level of depth of the recursion can be control with the number of recursions argument and if we want only the last level of recursion, the boolean argument onlyLastIteration need to be set as true.

	// Generator constructor
	public GeometricPatternFractalGenerator(
		List<SHAPE_TYPE> pattern,	// fractal pattern
		int numRecursions,			// recursion depth
		boolean lastIterOnly,		// only gather shapes computed @ last recursion level
		Consumer<Float> listener	// progress listener
	){  ...  }

• This class exposes two API methods to execute the generation (in memory) of the corresponding fractal descriptor:

	public void generateFractal()		// asynchronous generation
	public void generateFractalSync()	// synchronous generation

• After the generator finished generating the fractal descriptor (return from the synchronous call or receiving a finished generation event from the asynchronous call - described later here), the fractal descriptor can be accessed through the getFractal() method:

    List<SHAPE_TYPE> shapesGenerated = fractalGenerator.getFractal();
    shapesGenerated.stream().forEach(shape -> draw(shape));

• Asynchronous generation
  • In this case, the invocation of generateFractal() must be pair up with a reaction from the progress listener registered, with the following overall logic:

	Consumer<Float> progressListener = this::listenProgress;

	...

	public void listenProgress(float percentProgress)  {
		if (progress == IProgressUpdater.FINISHED_PROGRESS) {
			// The fractal generator has finished computing the fractal
		} else {
			// Update progress status if desired
		}
	}