Apecs.Util

Utility

runGC :: System w ()

Explicitly invoke the garbage collector

global :: Entity

Convenience entity, for use in places where the entity value does not matter, i.e. a global store.

EntityCounter

newtype EntityCounter

Component used by newEntity to track the number of issued entities. Automatically added to any world created with makeWorld

Constructors

EntityCounter

Fields

• getCounter :: Sum Int

Instances

Eq EntityCounter

Defined in Apecs.Util

Methods

(==) :: EntityCounter -> EntityCounter -> Bool

(/=) :: EntityCounter -> EntityCounter -> Bool

Show EntityCounter

Defined in Apecs.Util

Methods

showsPrec :: Int -> EntityCounter -> ShowS

show :: EntityCounter -> String

showList :: [EntityCounter] -> ShowS

Semigroup EntityCounter

Defined in Apecs.Util

Methods

(<>) :: EntityCounter -> EntityCounter -> EntityCounter

sconcat :: NonEmpty EntityCounter -> EntityCounter

stimes :: Integral b => b -> EntityCounter -> EntityCounter

Monoid EntityCounter

Defined in Apecs.Util

Methods

mempty :: EntityCounter

mappend :: EntityCounter -> EntityCounter -> EntityCounter

mconcat :: [EntityCounter] -> EntityCounter

Component EntityCounter

Defined in Apecs.Util

Associated Types

type Storage EntityCounter :: Type

type Storage EntityCounter

Defined in Apecs.Util

type Storage EntityCounter = ReadOnly (Global EntityCounter)

nextEntity :: (MonadIO m, Get w m EntityCounter) => SystemT w m Entity

Bumps the EntityCounter and yields its value

newEntity :: (MonadIO m, Set w m c, Get w m EntityCounter) => c -> SystemT w m Entity

Writes the given components to a new entity, and yields that entity. The return value is often ignored.

Spatial hashing

The following are helper functions for spatial hashing. Your spatial hash is defined by two vectors;

• The cell size vector contains real components and dictates how large each cell in your table is in world space units. It is used by quantize to translate a world space coordinate into a table space index vector
• The table size vector contains integral components and dictates how many cells your field consists of in each direction. It is used by flatten to translate a table-space index vector into a flat integer

quantize

Arguments

:: (Fractional (v a), Integral b, RealFrac a, Functor v)

=> v a

Quantization cell size

-> v a

Vector to be quantized

-> v b

Quantize turns a world-space coordinate into a table-space coordinate by dividing by the given cell size and rounding towards negative infinity.

flatten :: (Applicative v, Integral a, Foldable v) => v a -> v a -> Maybe a

Turns a table-space vector into an integral index, given some table size vector. Yields Nothing for out-of-bounds queries

inbounds :: (Num a, Ord a, Applicative v, Foldable v) => v a -> v a -> Bool

Tests whether a vector is in the region given by 0 and the size vector (inclusive)

region

Arguments

:: (Enum a, Applicative v, Traversable v)

=> v a

Lower bound for the region

-> v a

Higher bound for the region

-> [v a]

For two table-space vectors indicating a region's bounds, gives a list of the vectors contained between them. This is useful for querying a spatial hash.

flatten' :: (Applicative v, Integral a, Foldable v) => v a -> v a -> a

flatten, but yields garbage for out-of-bounds vectors.