Data.Path

SVG path manipulation

Path fundamental

Every element of an svg path can be thought of as exactly two points in space, with instructions of how to draw a curve between them. From this point of view, one which this library adopts, a path chart is thus very similar to a line chart. There's just a lot more information about the style of this line to deal with.

References:

SVG d

SVG path

data PathInfo a

To fit in with the requirements of the library design, specifically the separation of what a chart is into XY data Points from representation of these points, path instructions need to be decontructed into:

• define a single chart element as a line.
• split a single path element into the start and end points of the line, which become the xys of a Chart, and the rest of the information, which is called PathInfo and incorporated into the Chart annotation.

An arc path is variant to affine transformations of the xys points: angles are not presevred in the new reference frame.

Constructors

StartI

LineI

CubicI (Point a) (Point a)

QuadI (Point a)

ArcI (ArcInfo a)

Instances

Eq a => Eq (PathInfo a)

Defined in Data.Path

Methods

(==) :: PathInfo a -> PathInfo a -> Bool

(/=) :: PathInfo a -> PathInfo a -> Bool

Show a => Show (PathInfo a)

Defined in Data.Path

Methods

showsPrec :: Int -> PathInfo a -> ShowS

show :: PathInfo a -> String

showList :: [PathInfo a] -> ShowS

Generic (PathInfo a)

Defined in Data.Path

Associated Types

type Rep (PathInfo a) :: Type -> Type

Methods

from :: PathInfo a -> Rep (PathInfo a) x

to :: Rep (PathInfo a) x -> PathInfo a

type Rep (PathInfo a)

Defined in Data.Path

type Rep (PathInfo a) = D1 ('MetaData "PathInfo" "Data.Path" "chart-svg-0.2.2-AJskDBGhW2w5nFQE5Ah360" 'False) ((C1 ('MetaCons "StartI" 'PrefixI 'False) (U1 :: Type -> Type) :+: C1 ('MetaCons "LineI" 'PrefixI 'False) (U1 :: Type -> Type)) :+: (C1 ('MetaCons "CubicI" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a))) :+: (C1 ('MetaCons "QuadI" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a))) :+: C1 ('MetaCons "ArcI" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (ArcInfo a))))))

data ArcInfo a

Information about an individual arc path.

Constructors

ArcInfo

Fields

• radii :: Point a

  ellipse radii

• phi :: a

  rotation of the ellipse. positive means counter-clockwise (which is different to SVG).

• large :: Bool
• clockwise :: Bool

  sweep means clockwise

Instances

Eq a => Eq (ArcInfo a)

Defined in Data.Path

Methods

(==) :: ArcInfo a -> ArcInfo a -> Bool

(/=) :: ArcInfo a -> ArcInfo a -> Bool

Show a => Show (ArcInfo a)

Defined in Data.Path

Methods

showsPrec :: Int -> ArcInfo a -> ShowS

show :: ArcInfo a -> String

showList :: [ArcInfo a] -> ShowS

Generic (ArcInfo a)

Defined in Data.Path

Associated Types

type Rep (ArcInfo a) :: Type -> Type

Methods

from :: ArcInfo a -> Rep (ArcInfo a) x

to :: Rep (ArcInfo a) x -> ArcInfo a

type Rep (ArcInfo a)

Defined in Data.Path

type Rep (ArcInfo a) = D1 ('MetaData "ArcInfo" "Data.Path" "chart-svg-0.2.2-AJskDBGhW2w5nFQE5Ah360" 'False) (C1 ('MetaCons "ArcInfo" 'PrefixI 'True) ((S1 ('MetaSel ('Just "radii") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: S1 ('MetaSel ('Just "phi") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 a)) :*: (S1 ('MetaSel ('Just "large") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 Bool) :*: S1 ('MetaSel ('Just "clockwise") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 Bool))))

data ArcPosition a

Specification of an Arc using positional referencing as per SVG standard.

Constructors

ArcPosition

Fields

• posStart :: Point a
• posEnd :: Point a
• posInfo :: ArcInfo a

Instances

Eq a => Eq (ArcPosition a)

Defined in Data.Path

Methods

(==) :: ArcPosition a -> ArcPosition a -> Bool

(/=) :: ArcPosition a -> ArcPosition a -> Bool

Show a => Show (ArcPosition a)

Defined in Data.Path

Methods

showsPrec :: Int -> ArcPosition a -> ShowS

show :: ArcPosition a -> String

showList :: [ArcPosition a] -> ShowS

Generic (ArcPosition a)

Defined in Data.Path

Associated Types

type Rep (ArcPosition a) :: Type -> Type

Methods

from :: ArcPosition a -> Rep (ArcPosition a) x

to :: Rep (ArcPosition a) x -> ArcPosition a

type Rep (ArcPosition a)

Defined in Data.Path

type Rep (ArcPosition a) = D1 ('MetaData "ArcPosition" "Data.Path" "chart-svg-0.2.2-AJskDBGhW2w5nFQE5Ah360" 'False) (C1 ('MetaCons "ArcPosition" 'PrefixI 'True) (S1 ('MetaSel ('Just "posStart") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: (S1 ('MetaSel ('Just "posEnd") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: S1 ('MetaSel ('Just "posInfo") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (ArcInfo a)))))

parsePath :: Text -> [PathCommand]

parse a raw path string

>>> let outerseg1 = "M-1.0,0.5 A0.5 0.5 0.0 1 1 0.0,-1.2320508075688774 1.0 1.0 0.0 0 0 -0.5,-0.3660254037844387 1.0 1.0 0.0 0 0 -1.0,0.5 Z"
>>> parsePath outerseg1
[MoveTo OriginAbsolute [V2 (-1.0) 0.5],EllipticalArc OriginAbsolute [(0.5,0.5,0.0,True,True,V2 0.0 (-1.2320508075688774)),(1.0,1.0,0.0,False,False,V2 (-0.5) (-0.3660254037844387)),(1.0,1.0,0.0,False,False,V2 (-1.0) 0.5)],EndPath]

https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/d

toPathAbsolute

Arguments

:: (PathInfo Double, Point Double)

(info, start, end)

-> Text

path text

convert from a path info, start point, end point triple to a path text clause.

Note that morally,

toPathsAbsolute . toInfos . parsePath == id

but the round trip destroys much information, including:

• path text spacing
• Z, which is replaced by a LineI instruction from the end point back to the original start of the path.
• Sequences of the same instruction type are uncompressed
• As the name suggests, relative paths are translated to absolute ones.
• implicit L's in multiple M instructions are separated.

In converting between chart-svg and SVG there are two changes in reference:

• arc rotation is expressed as positive degrees for a clockwise rotation in SVG, and counter-clockwise in radians for chart-svg
• A positive y-direction is down for SVG and up for chart-svg

toPathCommand

Arguments

:: (PathInfo Double, Point Double)

-> PathCommand

path text

Convert from PathInfo to PathCommand

toPathAbsolutes :: [(PathInfo Double, Point Double)] -> Text

convert an (info, point) list to an svg d path text.

toPathXYs :: [PathCommand] -> [(PathInfo Double, Point Double)]

Convert from a path command list to a PathA specification

data ArcCentroid a

Arc specification based on centroidal interpretation.

See: https://www.w3.org/TR/SVG/implnote.html#ArcConversionEndpointToCenter

Constructors

ArcCentroid

Fields

• centroid :: Point a

  ellipse center

• radius :: Point a

  ellipse radii

• cphi :: a

  ellipse rotation

• ang0 :: a

  starting point angle to the x-axis

• angdiff :: a

  difference between ending point angle and starting point angle

Instances

Eq a => Eq (ArcCentroid a)

Defined in Data.Path

Methods

(==) :: ArcCentroid a -> ArcCentroid a -> Bool

(/=) :: ArcCentroid a -> ArcCentroid a -> Bool

Show a => Show (ArcCentroid a)

Defined in Data.Path

Methods

showsPrec :: Int -> ArcCentroid a -> ShowS

show :: ArcCentroid a -> String

showList :: [ArcCentroid a] -> ShowS

Generic (ArcCentroid a)

Defined in Data.Path

Associated Types

type Rep (ArcCentroid a) :: Type -> Type

Methods

from :: ArcCentroid a -> Rep (ArcCentroid a) x

to :: Rep (ArcCentroid a) x -> ArcCentroid a

type Rep (ArcCentroid a)

Defined in Data.Path

type Rep (ArcCentroid a) = D1 ('MetaData "ArcCentroid" "Data.Path" "chart-svg-0.2.2-AJskDBGhW2w5nFQE5Ah360" 'False) (C1 ('MetaCons "ArcCentroid" 'PrefixI 'True) ((S1 ('MetaSel ('Just "centroid") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: S1 ('MetaSel ('Just "radius") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a))) :*: (S1 ('MetaSel ('Just "cphi") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 a) :*: (S1 ('MetaSel ('Just "ang0") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 a) :*: S1 ('MetaSel ('Just "angdiff") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 a)))))

arcCentroid :: (FromInteger a, Ord a, TrigField a, ExpField a) => ArcPosition a -> ArcCentroid a

convert from an ArcPosition spec to ArcCentroid spec.

See also this

>>> let p = ArcPosition (Point 0 0) (Point 1 0) (ArcInfo (Point 1 0.5) (pi/4) False True)
>>> arcCentroid p
ArcCentroid {centroid = Point 0.20952624903444356 -0.48412291827592724, radius = Point 1.0 0.5, cphi = 0.7853981633974483, ang0 = 1.3753858999692936, angdiff = -1.823476581936975}

arcPosition :: (Ord a, Signed a, TrigField a) => ArcCentroid a -> ArcPosition a

convert from an ArcCentroid to an ArcPosition specification.

Morally, > arcPosition . arcCentroid == id

Not isomorphic if:

• angle diff is pi and large is True
• radii are less than they should be and thus get scaled up.

arcBox :: ArcPosition Double -> Rect Double

compute the bounding box for an arcBox

let p = ArcPosition (Point 0 0) (Point 1 0) (ArcInfo (Point 1 0.5) (pi/4) False True)
arcBox p

Rect -8.326672684688674e-17 0.9999999999999998 -5.551115123125783e-17 0.30644649676616753

arcDerivs :: Point Double -> Double -> (Double, Double)

potential arc turning points.

>>> arcDerivs (Point 1 0.5) (pi/4)
(-0.4636476090008061,0.4636476090008062)

ellipse :: (Direction b a, Affinity b a, TrigField a) => b -> b -> a -> a -> b

ellipse formulae

>>> ellipse zero (Point 1 2) (pi/6) pi
Point -0.8660254037844388 -0.4999999999999997

Compare this "elegent" definition from stackexchange

\[\dfrac{((x-h)\cos(A)+(y-k)\sin(A))^2}{a^2}+\dfrac{((x-h) \sin(A)-(y-k) \cos(A))^2}{b^2}=1\]

with the haskell code:

c + (rotate phi |. (r * ray theta))

See also: wolfram

data QuadPosition a

Quadratic bezier curve expressed in positional terms.

Constructors

QuadPosition

Fields

• qposStart :: Point a

  starting point

• qposEnd :: Point a

  ending point

• qposControl :: Point a

  control point

Instances

Eq a => Eq (QuadPosition a)

Defined in Data.Path

Methods

(==) :: QuadPosition a -> QuadPosition a -> Bool

(/=) :: QuadPosition a -> QuadPosition a -> Bool

Show a => Show (QuadPosition a)

Defined in Data.Path

Methods

showsPrec :: Int -> QuadPosition a -> ShowS

show :: QuadPosition a -> String

showList :: [QuadPosition a] -> ShowS

Generic (QuadPosition a)

Defined in Data.Path

Associated Types

type Rep (QuadPosition a) :: Type -> Type

Methods

from :: QuadPosition a -> Rep (QuadPosition a) x

to :: Rep (QuadPosition a) x -> QuadPosition a

type Rep (QuadPosition a)

Defined in Data.Path

type Rep (QuadPosition a) = D1 ('MetaData "QuadPosition" "Data.Path" "chart-svg-0.2.2-AJskDBGhW2w5nFQE5Ah360" 'False) (C1 ('MetaCons "QuadPosition" 'PrefixI 'True) (S1 ('MetaSel ('Just "qposStart") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: (S1 ('MetaSel ('Just "qposEnd") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: S1 ('MetaSel ('Just "qposControl") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)))))

data QuadPolar a

Quadratic bezier curve with control point expressed in polar terms normalised to the start - end line.

Constructors

QuadPolar

Fields

• qpolStart :: Point a

  starting point

• qpolEnd :: Point a

  ending point

• qpolControl :: Polar a a

  control point in terms of distance from and angle to the qp0 - qp2 line

Instances

Eq a => Eq (QuadPolar a)

Defined in Data.Path

Methods

(==) :: QuadPolar a -> QuadPolar a -> Bool

(/=) :: QuadPolar a -> QuadPolar a -> Bool

Show a => Show (QuadPolar a)

Defined in Data.Path

Methods

showsPrec :: Int -> QuadPolar a -> ShowS

show :: QuadPolar a -> String

showList :: [QuadPolar a] -> ShowS

Generic (QuadPolar a)

Defined in Data.Path

Associated Types

type Rep (QuadPolar a) :: Type -> Type

Methods

from :: QuadPolar a -> Rep (QuadPolar a) x

to :: Rep (QuadPolar a) x -> QuadPolar a

type Rep (QuadPolar a)

Defined in Data.Path

type Rep (QuadPolar a) = D1 ('MetaData "QuadPolar" "Data.Path" "chart-svg-0.2.2-AJskDBGhW2w5nFQE5Ah360" 'False) (C1 ('MetaCons "QuadPolar" 'PrefixI 'True) (S1 ('MetaSel ('Just "qpolStart") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: (S1 ('MetaSel ('Just "qpolEnd") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: S1 ('MetaSel ('Just "qpolControl") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Polar a a)))))

quadPosition :: (ExpField a, TrigField a) => QuadPolar a -> QuadPosition a

Convert from a polar to a positional representation of a quadratic bezier.

quadPosition . quadPolar == id
quadPolar . quadPosition == id

>>> quadPosition $ quadPolar (QuadPosition (Point 0 0) (Point 1 1) (Point 2 -1))
QuadPosition {qposStart = Point 0.0 0.0, qposEnd = Point 1.0 1.0, qposControl = Point 2.0 -0.9999999999999998}

quadPolar :: (ExpField a, TrigField a) => QuadPosition a -> QuadPolar a

Convert from a positional to a polar representation of a cubic bezier.

>>> quadPolar (QuadPosition (Point 0 0) (Point 1 1) (Point 2 -1))
QuadPolar {qpolStart = Point 0.0 0.0, qpolEnd = Point 1.0 1.0, qpolControl = Polar {magnitude = 2.1213203435596424, direction = -0.7853981633974483}}

quadBox :: QuadPosition Double -> Rect Double

Bounding box for a QuadPosition

>>> quadBox (QuadPosition (Point 0 0) (Point 1 1) (Point 2 -1))
Rect 0.0 1.3333333333333335 -0.33333333333333337 1.0

quadBezier :: (ExpField a, FromInteger a) => QuadPosition a -> a -> Point a

The quadratic bezier equation

>>> quadBezier (QuadPosition (Point 0 0) (Point 1 1) (Point 2 -1)) 0.33333333
Point 0.9999999933333332 -0.33333333333333326

quadDerivs :: QuadPosition Double -> [Double]

QuadPosition turning points.

>>> quadDerivs (QuadPosition (Point 0 0) (Point 1 1) (Point 2 -1))
[0.6666666666666666,0.3333333333333333]

data CubicPosition a

cubic bezier curve

Note that the ordering is different to the svg standard.

Constructors

CubicPosition

Fields

• cposStart :: Point a

  starting point

• cposEnd :: Point a

  ending point

• cposControl1 :: Point a

  control point 1

• cposControl2 :: Point a

  control point 2

Instances

Eq a => Eq (CubicPosition a)

Defined in Data.Path

Methods

(==) :: CubicPosition a -> CubicPosition a -> Bool

(/=) :: CubicPosition a -> CubicPosition a -> Bool

Show a => Show (CubicPosition a)

Defined in Data.Path

Methods

showsPrec :: Int -> CubicPosition a -> ShowS

show :: CubicPosition a -> String

showList :: [CubicPosition a] -> ShowS

Generic (CubicPosition a)

Defined in Data.Path

Associated Types

type Rep (CubicPosition a) :: Type -> Type

Methods

from :: CubicPosition a -> Rep (CubicPosition a) x

to :: Rep (CubicPosition a) x -> CubicPosition a

type Rep (CubicPosition a)

Defined in Data.Path

type Rep (CubicPosition a) = D1 ('MetaData "CubicPosition" "Data.Path" "chart-svg-0.2.2-AJskDBGhW2w5nFQE5Ah360" 'False) (C1 ('MetaCons "CubicPosition" 'PrefixI 'True) ((S1 ('MetaSel ('Just "cposStart") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: S1 ('MetaSel ('Just "cposEnd") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a))) :*: (S1 ('MetaSel ('Just "cposControl1") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: S1 ('MetaSel ('Just "cposControl2") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)))))

data CubicPolar a

A polar representation of a cubic bezier with control points expressed as polar and normalised to the start - end line.

Constructors

CubicPolar

Fields

• cpolStart :: Point a

  starting point

• cpolEnd :: Point a

  ending point

• cpolControl1 :: Polar a a

  control point in terms of distance from and angle to the start end line

• cpolControl2 :: Polar a a

  control point in terms of distance from and angle to the start end line

Instances

Eq a => Eq (CubicPolar a)

Defined in Data.Path

Methods

(==) :: CubicPolar a -> CubicPolar a -> Bool

(/=) :: CubicPolar a -> CubicPolar a -> Bool

Show a => Show (CubicPolar a)

Defined in Data.Path

Methods

showsPrec :: Int -> CubicPolar a -> ShowS

show :: CubicPolar a -> String

showList :: [CubicPolar a] -> ShowS

Generic (CubicPolar a)

Defined in Data.Path

Associated Types

type Rep (CubicPolar a) :: Type -> Type

Methods

from :: CubicPolar a -> Rep (CubicPolar a) x

to :: Rep (CubicPolar a) x -> CubicPolar a

type Rep (CubicPolar a)

Defined in Data.Path

type Rep (CubicPolar a) = D1 ('MetaData "CubicPolar" "Data.Path" "chart-svg-0.2.2-AJskDBGhW2w5nFQE5Ah360" 'False) (C1 ('MetaCons "CubicPolar" 'PrefixI 'True) ((S1 ('MetaSel ('Just "cpolStart") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a)) :*: S1 ('MetaSel ('Just "cpolEnd") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Point a))) :*: (S1 ('MetaSel ('Just "cpolControl1") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Polar a a)) :*: S1 ('MetaSel ('Just "cpolControl2") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedStrict) (Rec0 (Polar a a)))))

cubicPosition :: (ExpField a, TrigField a) => CubicPolar a -> CubicPosition a

Convert from a polar to a positional representation of a cubic bezier.

cubicPosition . cubicPolar == id
cubicPolar . cubicPosition == id

>>> cubicPosition $ cubicPolar (CubicPosition (Point 0 0) (Point 1 1) (Point 1 -1) (Point 0 2))
CubicPosition {cposStart = Point 0.0 0.0, cposEnd = Point 1.0 1.0, cposControl1 = Point 1.0 -1.0, cposControl2 = Point 1.6653345369377348e-16 2.0}

cubicPolar :: (ExpField a, TrigField a) => CubicPosition a -> CubicPolar a

Convert from a positional to a polar representation of a cubic bezier.

cubicPosition . cubicPolar == id
cubicPolar . cubicPosition == id

>>> cubicPolar (CubicPosition (Point 0 0) (Point 1 1) (Point 1 -1) (Point 0 2))
CubicPolar {cpolStart = Point 0.0 0.0, cpolEnd = Point 1.0 1.0, cpolControl1 = Polar {magnitude = 1.1180339887498947, direction = -1.2490457723982544}, cpolControl2 = Polar {magnitude = 1.1180339887498947, direction = 1.8925468811915387}}

cubicBox :: CubicPosition Double -> Rect Double

Bounding box for a CubicPosition

>>> cubicBox (CubicPosition (Point 0 0) (Point 1 1) (Point 1 -1) (Point 0 2))
Rect 0.0 1.0 -0.20710678118654752 1.2071067811865475

cubicBezier :: (ExpField a, FromInteger a) => CubicPosition a -> a -> Point a

The cubic bezier equation

>>> cubicBezier (CubicPosition (Point 0 0) (Point 1 1) (Point 1 -1) (Point 0 2)) 0.8535533905932737
Point 0.6767766952966369 1.2071067811865475

cubicDerivs :: CubicPosition Double -> [Double]

Turning point positions for a CubicPosition (0,1 or 2)

>>> cubicDerivs (CubicPosition (Point 0 0) (Point 1 1) (Point 1 -1) (Point 0 2))
[0.8535533905932737,0.14644660940672624,0.5]

singletonCubic :: CubicPosition Double -> [(PathInfo Double, Point Double)]

convert cubic position to path info.

singletonQuad :: QuadPosition Double -> [(PathInfo Double, Point Double)]

convert quad position to path info.

singletonArc :: ArcPosition Double -> [(PathInfo Double, Point Double)]

convert arc position to path info.

singletonPie :: ArcPosition Double -> [(PathInfo Double, Point Double)]

convert arc position to a pie slice.

singletonPie' :: Point Double -> ArcPosition Double -> [(PathInfo Double, Point Double)]

convert arc position to a pie slice, with a specific center.

toSingletonArc :: [(PathInfo Double, Point Double)] -> Maybe (ArcPosition Double)

convert path info to an ArcPosition.

pathBoxes :: [(PathInfo Double, Point Double)] -> Maybe (Rect Double)

Bounding box for a list of path XYs.

pathBox :: Point Double -> (PathInfo Double, Point Double) -> Rect Double

Bounding box for a path info, start and end Points.