{-# LANGUAGE FlexibleContexts #-} {-# LANGUAGE TemplateHaskell #-} {-# LANGUAGE TypeFamilies #-} ----------------------------------------------------------------------------- -- | -- Module : Diagrams.TwoD.Shapes -- Copyright : (c) 2011 diagrams-lib team (see LICENSE) -- License : BSD-style (see LICENSE) -- Maintainer : diagrams-discuss@googlegroups.com -- -- Various two-dimensional shapes. -- ----------------------------------------------------------------------------- module Diagrams.TwoD.Shapes ( -- * Miscellaneous hrule, vrule -- * Regular polygons , regPoly , triangle , eqTriangle , square , pentagon , hexagon , heptagon , septagon , octagon , nonagon , decagon , hendecagon , dodecagon -- * Other special polygons , unitSquare , rect -- * Other shapes , roundedRect , RoundedRectOpts(..), radiusTL, radiusTR, radiusBL, radiusBR , roundedRect' ) where import Control.Lens (makeLenses, op, (&), (.~), (<>~), (^.)) import Data.Default.Class import Data.Semigroup import Diagrams.Core import Diagrams.Angle import Diagrams.Located (at) import Diagrams.Path import Diagrams.Segment import Diagrams.Trail import Diagrams.TrailLike import Diagrams.TwoD.Arc import Diagrams.TwoD.Polygons import Diagrams.TwoD.Transform import Diagrams.TwoD.Types import Diagrams.TwoD.Vector import Diagrams.Util -- | Create a centered horizontal (L-R) line of the given length. -- -- <> -- -- > hruleEx = vcat' (with & sep .~ 0.2) (map hrule [1..5]) -- > # centerXY # pad 1.1 hrule :: (InSpace V2 n t, TrailLike t) => n -> t hrule d = trailLike $ trailFromSegments [straight $ r2 (d, 0)] `at` p2 (-d/2,0) -- | Create a centered vertical (T-B) line of the given length. -- -- <> -- -- > vruleEx = hcat' (with & sep .~ 0.2) (map vrule [1, 1.2 .. 2]) -- > # centerXY # pad 1.1 vrule :: (InSpace V2 n t, TrailLike t) => n -> t vrule d = trailLike $ trailFromSegments [straight $ r2 (0, -d)] `at` p2 (0,d/2) -- | A square with its center at the origin and sides of length 1, -- oriented parallel to the axes. -- -- <> unitSquare :: (InSpace V2 n t, TrailLike t) => t unitSquare = polygon (def & polyType .~ PolyRegular 4 (sqrt 2 / 2) & polyOrient .~ OrientH) -- > unitSquareEx = unitSquare # pad 1.1 # showOrigin -- | A square with its center at the origin and sides of the given -- length, oriented parallel to the axes. -- -- <> square :: (InSpace V2 n t, TrailLike t) => n -> t square d = rect d d -- > squareEx = hcat' (with & sep .~ 0.5) [square 1, square 2, square 3] -- > # centerXY # pad 1.1 -- | @rect w h@ is an axis-aligned rectangle of width @w@ and height -- @h@, centered at the origin. -- -- <> rect :: (InSpace V2 n t, TrailLike t) => n -> n -> t rect w h = trailLike . head . op Path $ unitSquare # scaleX w # scaleY h -- > rectEx = rect 1 0.7 # pad 1.1 -- The above may seem a bit roundabout. In fact, we used to have -- -- rect w h = unitSquare # scaleX w # scaleY h -- -- since unitSquare can produce any TrailLike. The current code -- instead uses (unitSquare # scaleX w # scaleY h) to specifically -- produce a Path, which is then deconstructed and passed back into -- 'trailLike' to create any TrailLike. -- -- The difference is that while scaling by zero works fine for -- Path it does not work very well for, say, Diagrams (leading to -- NaNs or worse). This way, we force the scaling to happen on a -- Path, where we know it will behave properly, and then use the -- resulting geometry to construct an arbitrary TrailLike. -- -- See https://github.com/diagrams/diagrams-lib/issues/43 . ------------------------------------------------------------ -- Regular polygons ------------------------------------------------------------ -- | Create a regular polygon. The first argument is the number of -- sides, and the second is the /length/ of the sides. (Compare to the -- 'polygon' function with a 'PolyRegular' option, which produces -- polygons of a given /radius/). -- -- The polygon will be oriented with one edge parallel to the x-axis. regPoly :: (InSpace V2 n t, TrailLike t) => Int -> n -> t regPoly n l = polygon (def & polyType .~ PolySides (repeat (1/fromIntegral n @@ turn)) (replicate (n-1) l) & polyOrient .~ OrientH ) -- > shapeEx sh = sh 1 # pad 1.1 -- > triangleEx = shapeEx triangle -- > pentagonEx = shapeEx pentagon -- > hexagonEx = shapeEx hexagon -- > heptagonEx = shapeEx heptagon -- > octagonEx = shapeEx octagon -- > nonagonEx = shapeEx nonagon -- > decagonEx = shapeEx decagon -- > hendecagonEx = shapeEx hendecagon -- > dodecagonEx = shapeEx dodecagon -- | A synonym for 'triangle', provided for backwards compatibility. eqTriangle :: (InSpace V2 n t, TrailLike t) => n -> t eqTriangle = triangle -- | An equilateral triangle, with sides of the given length and base -- parallel to the x-axis. -- -- <> triangle :: (InSpace V2 n t, TrailLike t) => n -> t triangle = regPoly 3 -- | A regular pentagon, with sides of the given length and base -- parallel to the x-axis. -- -- <> pentagon :: (InSpace V2 n t, TrailLike t) => n -> t pentagon = regPoly 5 -- | A regular hexagon, with sides of the given length and base -- parallel to the x-axis. -- -- <> hexagon :: (InSpace V2 n t, TrailLike t) => n -> t hexagon = regPoly 6 -- | A regular heptagon, with sides of the given length and base -- parallel to the x-axis. -- -- <> heptagon :: (InSpace V2 n t, TrailLike t) => n -> t heptagon = regPoly 7 -- | A synonym for 'heptagon'. It is, however, completely inferior, -- being a base admixture of the Latin /septum/ (seven) and the -- Greek γωνία (angle). septagon :: (InSpace V2 n t, TrailLike t) => n -> t septagon = heptagon -- | A regular octagon, with sides of the given length and base -- parallel to the x-axis. -- -- <> octagon :: (InSpace V2 n t, TrailLike t) => n -> t octagon = regPoly 8 -- | A regular nonagon, with sides of the given length and base -- parallel to the x-axis. -- -- <> nonagon :: (InSpace V2 n t, TrailLike t) => n -> t nonagon = regPoly 9 -- | A regular decagon, with sides of the given length and base -- parallel to the x-axis. -- -- <> decagon :: (InSpace V2 n t, TrailLike t) => n -> t decagon = regPoly 10 -- | A regular hendecagon, with sides of the given length and base -- parallel to the x-axis. -- -- <> hendecagon :: (InSpace V2 n t, TrailLike t) => n -> t hendecagon = regPoly 11 -- | A regular dodecagon, with sides of the given length and base -- parallel to the x-axis. -- -- <> dodecagon :: (InSpace V2 n t, TrailLike t) => n -> t dodecagon = regPoly 12 ------------------------------------------------------------ -- Other shapes ------------------------------------------ ------------------------------------------------------------ data RoundedRectOpts d = RoundedRectOpts { _radiusTL :: d , _radiusTR :: d , _radiusBL :: d , _radiusBR :: d } makeLenses ''RoundedRectOpts instance (Num d) => Default (RoundedRectOpts d) where def = RoundedRectOpts 0 0 0 0 -- | @roundedRect w h r@ generates a closed trail, or closed path -- centered at the origin, of an axis-aligned rectangle with width -- @w@, height @h@, and circular rounded corners of radius @r@. If -- @r@ is negative the corner will be cut out in a reverse arc. If -- the size of @r@ is larger than half the smaller dimension of @w@ -- and @h@, then it will be reduced to fit in that range, to prevent -- the corners from overlapping. The trail or path begins with the -- right edge and proceeds counterclockwise. If you need to specify -- a different radius for each corner individually, use -- 'roundedRect'' instead. -- -- <> -- -- > roundedRectEx = pad 1.1 . centerXY $ hcat' (with & sep .~ 0.2) -- > [ roundedRect 0.5 0.4 0.1 -- > , roundedRect 0.5 0.4 (-0.1) -- > , roundedRect' 0.7 0.4 (with & radiusTL .~ 0.2 -- > & radiusTR .~ -0.2 -- > & radiusBR .~ 0.1) -- > ] roundedRect :: (InSpace V2 n t, TrailLike t, RealFloat n) => n -> n -> n -> t roundedRect w h r = roundedRect' w h (def & radiusTL .~ r & radiusBR .~ r & radiusTR .~ r & radiusBL .~ r) -- | @roundedRect'@ works like @roundedRect@ but allows you to set the radius of -- each corner indivually, using @RoundedRectOpts@. The default corner radius is 0. -- Each radius can also be negative, which results in the curves being reversed -- to be inward instead of outward. roundedRect' :: (InSpace V2 n t, TrailLike t, RealFloat n) => n -> n -> RoundedRectOpts n -> t roundedRect' w h opts = trailLike . (`at` p2 (w/2, abs rBR - h/2)) . wrapTrail . glueLine $ seg (0, h - abs rTR - abs rBR) <> mkCorner 0 rTR <> seg (abs rTR + abs rTL - w, 0) <> mkCorner 1 rTL <> seg (0, abs rTL + abs rBL - h) <> mkCorner 2 rBL <> seg (w - abs rBL - abs rBR, 0) <> mkCorner 3 rBR where seg = lineFromOffsets . (:[]) . r2 diag = sqrt (w * w + h * h) -- to clamp corner radius, need to compare with other corners that share an -- edge. If the corners overlap then reduce the largest corner first, as far -- as 50% of the edge in question. rTL = clampCnr radiusTR radiusBL radiusBR radiusTL rBL = clampCnr radiusBR radiusTL radiusTR radiusBL rTR = clampCnr radiusTL radiusBR radiusBL radiusTR rBR = clampCnr radiusBL radiusTR radiusTL radiusBR clampCnr rx ry ro r = let (rx',ry',ro',r') = (opts^.rx, opts^.ry, opts^.ro, opts^.r) in clampDiag ro' . clampAdj h ry' . clampAdj w rx' $ r' -- prevent curves of adjacent corners from overlapping clampAdj len adj r = if abs r > len/2 then sign r * max (len/2) (min (len - abs adj) (abs r)) else r -- prevent inward curves of diagonally opposite corners from intersecting clampDiag opp r = if r < 0 && opp < 0 && abs r > diag / 2 then sign r * max (diag / 2) (min (abs r) (diag + opp)) else r sign n = if n < 0 then -1 else 1 mkCorner k r | r == 0 = mempty | r < 0 = doArc 3 (-1) | otherwise = doArc 0 1 where doArc d s = arc' r (xDir & _theta <>~ ((k+d)/4 @@ turn)) (s/4 @@ turn)