LambdaHack-0.6.1.0: A game engine library for roguelike dungeon crawlers

Safe HaskellNone
LanguageHaskell2010

Game.LambdaHack.Common.Vector

Description

Basic operations on 2D vectors represented in an efficient, but not unique, way.

Synopsis

Documentation

data Vector Source #

2D vectors in cartesian representation. Coordinates grow to the right and down, so that the (1, 1) vector points to the bottom-right corner of the screen.

Constructors

Vector 

Fields

Instances

Enum Vector Source # 
Eq Vector Source # 

Methods

(==) :: Vector -> Vector -> Bool #

(/=) :: Vector -> Vector -> Bool #

Ord Vector Source # 
Read Vector Source # 
Show Vector Source # 
Generic Vector Source # 

Associated Types

type Rep Vector :: * -> * #

Methods

from :: Vector -> Rep Vector x #

to :: Rep Vector x -> Vector #

Binary Vector Source # 

Methods

put :: Vector -> Put #

get :: Get Vector #

putList :: [Vector] -> Put #

NFData Vector Source # 

Methods

rnf :: Vector -> () #

type Rep Vector Source # 
type Rep Vector = D1 * (MetaData "Vector" "Game.LambdaHack.Common.Vector" "LambdaHack-0.6.1.0-HURqEs4cFyW7LJywblRLqn" False) (C1 * (MetaCons "Vector" PrefixI True) ((:*:) * (S1 * (MetaSel (Just Symbol "vx") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 * X)) (S1 * (MetaSel (Just Symbol "vy") NoSourceUnpackedness SourceStrict DecidedStrict) (Rec0 * Y))))

isUnit :: Vector -> Bool Source #

Tells if a vector has length 1 in the chessboard metric.

isDiagonal :: Vector -> Bool Source #

Checks whether a unit vector is a diagonal direction, as opposed to cardinal. If the vector is not unit, it checks that the vector is not horizontal nor vertical.

neg :: Vector -> Vector Source #

Reverse an arbirary vector.

chessDistVector :: Vector -> Int Source #

The lenght of a vector in the chessboard metric, where diagonal moves cost 1.

euclidDistSqVector :: Vector -> Vector -> Int Source #

Squared euclidean distance between two vectors.

moves :: [Vector] Source #

Vectors of all unit moves in the chessboard metric, clockwise, starting north-west.

movesCardinal :: [Vector] Source #

Vectors of all cardinal direction unit moves, clockwise, starting north.

movesDiagonal :: [Vector] Source #

Vectors of all diagonal direction unit moves, clockwise, starting north.

vicinity Source #

Arguments

:: X 
-> Y

limit the search to this area

-> Point

position to find neighbours of

-> [Point] 

All (8 at most) closest neighbours of a point within an area.

vicinityCardinal Source #

Arguments

:: X 
-> Y

limit the search to this area

-> Point

position to find neighbours of

-> [Point] 

All (4 at most) cardinal direction neighbours of a point within an area.

shift :: Point -> Vector -> Point Source #

Translate a point by a vector.

shiftBounded :: X -> Y -> Point -> Vector -> Point Source #

Translate a point by a vector, but only if the result fits in an area.

trajectoryToPath :: Point -> [Vector] -> [Point] Source #

A list of points that a list of vectors leads to.

trajectoryToPathBounded :: X -> Y -> Point -> [Vector] -> [Point] Source #

A list of points that a list of vectors leads to, bounded by level size.

vectorToFrom :: Point -> Point -> Vector Source #

The vector between the second point and the first. We have

shift pos1 (pos2 `vectorToFrom` pos1) == pos2

The arguments are in the same order as in the underlying scalar subtraction.

pathToTrajectory :: [Point] -> [Vector] Source #

A list of vectors between a list of points.

rotate :: RadianAngle -> Vector -> Vector Source #

Rotate a vector by the given angle (expressed in radians) counterclockwise and return a unit vector approximately in the resulting direction.

towards :: Point -> Point -> Vector Source #

Given two distinct positions, determine the direction (a unit vector) in which one should move from the first in order to get closer to the second. Ignores obstacles. Of several equally good directions (in the chessboard metric) it picks one of those that visually (in the euclidean metric) maximally align with the vector between the two points.