Copyright	(c) 2013 diagrams-lib team (see LICENSE)
License	BSD-style (see LICENSE)
Maintainer	diagrams-discuss@googlegroups.com
Safe Haskell	None
Language	Haskell2010

Diagrams.TwoD.Arrow

Contents

Examples
- Example 1
- Example 2
Creating arrows
Options

Description

Drawing arrows in two dimensions. For a tutorial on drawing arrows using this module, see the diagrams website: http://projects.haskell.org/diagrams/doc/arrow.html.

Synopsis

Examples

Example 1

-- Connecting two diagrams at their origins.

sq = square 2 # showOrigin # lc darkgray # lw ultraThick
ds = (sq # named "left") ||| strutX 3 ||| (sq # named "right")

shaft  = cubicSpline False ( map p2 [(0, 0), (1, 0), (1, 0.2), (2, 0.2)])

example1 = ds # connect' (with & arrowHead .~ dart & arrowTail .~ quill
                               & arrowShaft .~ shaft
                               & headLength .~ huge & tailLength .~ veryLarge)
                               "left" "right" # pad 1.1

Example 2

-- Comparing connect, connectPerim, and arrowAt.

oct  = octagon 1 # lc darkgray # lw ultraThick # showOrigin
dias = oct # named "first" ||| strut 3 ||| oct # named "second"

-- Connect two diagrams and two points on their trails.
ex12 = dias # connect' (with & lengths .~ veryLarge) "first" "second"
            # connectPerim' (with & lengths .~ veryLarge)
       "first" "second" (15/16 @@ turn) (9/16 @@ turn)

-- Place an arrow at (0,0) the size and direction of (0,1).
ex3 = arrowAt origin unit_Y

example2 = (ex12 <> ex3) # centerXY # pad 1.1

Creating arrows

arrowV :: Renderable (Path R2) b => R2 -> Diagram b R2 Source

arrowV v creates an arrow with the direction and magnitude of the vector v (with its tail at the origin), using default parameters.

arrowV' :: Renderable (Path R2) b => ArrowOpts -> R2 -> Diagram b R2 Source

arrowV' v creates an arrow with the direction and magnitude of the vector v (with its tail at the origin).

arrowAt :: Renderable (Path R2) b => P2 -> R2 -> Diagram b R2 Source

Create an arrow starting at s with length and direction determined by the vector v.

arrowAt' :: Renderable (Path R2) b => ArrowOpts -> P2 -> R2 -> Diagram b R2 Source

arrowBetween :: Renderable (Path R2) b => P2 -> P2 -> Diagram b R2 Source

arrowBetween s e creates an arrow pointing from s to e with default parameters.

arrowBetween' :: Renderable (Path R2) b => ArrowOpts -> P2 -> P2 -> Diagram b R2 Source

arrowBetween' opts s e creates an arrow pointing from s to e using the given options. In particular, it scales and rotates arrowShaft to go between s and e, taking head, tail, and gaps into account.

connect :: (Renderable (Path R2) b, IsName n1, IsName n2) => n1 -> n2 -> Diagram b R2 -> Diagram b R2 Source

Connect two diagrams with a straight arrow.

connect' :: (Renderable (Path R2) b, IsName n1, IsName n2) => ArrowOpts -> n1 -> n2 -> Diagram b R2 -> Diagram b R2 Source

Connect two diagrams with an arbitrary arrow.

connectPerim :: (Renderable (Path R2) b, IsName n1, IsName n2) => n1 -> n2 -> Angle -> Angle -> Diagram b R2 -> Diagram b R2 Source

Connect two diagrams at point on the perimeter of the diagrams, choosen by angle.

connectPerim' :: (Renderable (Path R2) b, IsName n1, IsName n2) => ArrowOpts -> n1 -> n2 -> Angle -> Angle -> Diagram b R2 -> Diagram b R2 Source

connectOutside :: (Renderable (Path R2) b, IsName n1, IsName n2) => n1 -> n2 -> Diagram b R2 -> Diagram b R2 Source

Draw an arrow from diagram named "n1" to diagram named "n2". The arrow lies on the line between the centres of the diagrams, but is drawn so that it stops at the boundaries of the diagrams, using traces to find the intersection points.

connectOutside' :: (Renderable (Path R2) b, IsName n1, IsName n2) => ArrowOpts -> n1 -> n2 -> Diagram b R2 -> Diagram b R2 Source

arrow :: Renderable (Path R2) b => Double -> Diagram b R2 Source

arrow len creates an arrow of length len with default parameters, starting at the origin and ending at the point (len,0).

arrow' :: Renderable (Path R2) b => ArrowOpts -> Double -> Diagram b R2 Source

arrow' opts len creates an arrow of length len using the given options, starting at the origin and ending at the point (len,0). In particular, it scales the given arrowShaft so that the entire arrow has length len.

Options

data ArrowOpts Source

Constructors

ArrowOpts
Fields _arrowHead :: ArrowHT _arrowTail :: ArrowHT _arrowShaft :: Trail R2 _headGap :: Measure R2 _tailGap :: Measure R2 _headStyle :: Style R2 _headLength :: Measure R2 _tailStyle :: Style R2 _tailLength :: Measure R2 _shaftStyle :: Style R2

Instances

Default ArrowOpts

arrowHead :: Lens' ArrowOpts ArrowHT Source

A shape to place at the head of the arrow.

arrowTail :: Lens' ArrowOpts ArrowHT Source

A shape to place at the tail of the arrow.

arrowShaft :: Lens' ArrowOpts (Trail R2) Source

The trail to use for the arrow shaft.

headGap :: Lens' ArrowOpts (Measure R2) Source

Distance to leave between the head and the target point.

tailGap :: Lens' ArrowOpts (Measure R2) Source

Distance to leave between the starting point and the tail.

gaps :: Traversal' ArrowOpts (Measure R2) Source

Set both the headGap and tailGap simultaneously.

gap :: Traversal' ArrowOpts (Measure R2) Source

Same as gaps, provided for backward compatiiblity.

headTexture :: Setter' ArrowOpts Texture Source

A lens for setting or modifying the texture of an arrowhead. For example, one may write ... (with & headTexture .~ grad) to get an arrow with a head filled with a gradient, assuming grad has been defined. Or ... (with & headTexture .~ solid blue to set the head color to blue. For more general control over the style of arrowheads, see headStyle.

headStyle :: Lens' ArrowOpts (Style R2) Source

Style to apply to the head. headStyle is modified by using the lens combinator %~ to change the current style. For example, to change an opaque black arrowhead to translucent orange: (with & headStyle %~ fc orange . opacity 0.75).

headLength :: Lens' ArrowOpts (Measure R2) Source

The length from the start of the joint to the tip of the head.

tailTexture :: Setter' ArrowOpts Texture Source

A lens for setting or modifying the texture of an arrow tail.

tailStyle :: Lens' ArrowOpts (Style R2) Source

Style to apply to the tail. See headStyle.

tailLength :: Lens' ArrowOpts (Measure R2) Source

The length of the tail plus its joint.

lengths :: Traversal' ArrowOpts (Measure R2) Source

Set both the headLength and tailLength simultaneously.

shaftTexture :: Setter' ArrowOpts Texture Source

A lens for setting or modifying the texture of an arrow shaft.