Struct LSSampler

pub struct LSSampler { /* private fields */ }

Creates Transformation samples for a given item. The samples are drawn from normal distributions with decaying standard deviations. Each time an improvement is found, the mean of the distributions is shifted to the new best transformation.

Implementations

impl LSSampler

pub fn new( item: &Item, ref_transform: &DTransformation, sd_transl_range: (fsize, fsize), sd_rot_range: (fsize, fsize), ) -> Self

pub fn from_defaults( item: &Item, ref_transform: &DTransformation, bbox: &AARectangle, ) -> Self

Creates a new sampler with default standard deviation ranges: SD_TRANSL and SD_ROT.

pub fn shift_mean(&mut self, ref_transform: &DTransformation)

Shifts the mean of the normal distributions to the given reference transformation.

pub fn set_stddev(&mut self, stddev_transl: fsize, stddev_rot: fsize)

Sets the standard deviation of the normal distributions.

pub fn decay_stddev(&mut self, progress_pct: fsize)

Adjusts the standard deviation according to the fraction of samples that have passed, following an exponential decay curve. progress_pct is a value in [0, 1].

f(0) = init; f(1) = end; f(x) = init * (end/init)^x;

pub fn sample(&mut self, rng: &mut impl Rng) -> DTransformation

Samples a transformation from the distribution.