State initialization

The MOOG Environment class takes a state_initializer keyword argument that is a callable returning an initial state at the beginning of each episode. This directory contains tools for creating such a state initializer.

Distributions

The distributions.py file contains a library of distributions that can be composed to create arbitrarily complex distributions of sprite factors. If you find yourself beginning to implement a complicate sampler to generate sprite factors, check distributions.py to see if some of the tools there can be used.

Sprite generators

The sprite_generators.py file contains functions for generating lists of multiple sprites from the same distribution. In many cases, these functions don't save much space in the config (it's easy to sample by hand: sprites = [Sprite(**my_factor_distrib.sample() for _ in range(num_sprites)]). However, the tools in sprite_generators.py do offer some additional functionality that may be useful: * Sampling disjoint sprites. The disjoint boolean argument in a sprite generator can be used to force all generated sprites to not overlap. * Sampling sprites that don't overlap other sprites. The without_overlapping argument can be a list of sprites, in which case all generated sprites are forced to not overlap any of those in the given list.

Cross-Trial Dependencies

In some cases, you might want to implement a task where there the initial state is not sampled independently each trial, but instead depends on some aspect of previous trials (e.g. maybe there's a Poisson rule switch that happens every few trials). The easiest way to do this is to make the state_initializer a method of a class. Namely, instead of making it a function in the config, make it a method of a class and let the class's state monitor the necessary cross-trial data. For a simple example of this, see the predators_arena.py example config.

""".. include:: README.md"""

Sub-modules

moog.state_initialization.distributions

Factor distribution library …

moog.state_initialization.sprite_generators

Generators for producing lists of sprites based on factor distributions.