Reorganise geometry modules slightly
This commit is contained in:
+1
-1
@@ -7,7 +7,7 @@ import Dodge.Wall.Delete
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import Dodge.Wall.Dust
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import Dodge.RandomHelp
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import Geometry
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import Geometry.ConvexPoly
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--import Geometry.ConvexPoly
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import Data.Function
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import qualified Data.IntSet as IS
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@@ -3,7 +3,7 @@ module Dodge.Creature.Boid
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import Dodge.Data
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import Dodge.Base
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import Geometry
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import Geometry.ConvexPoly
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--import Geometry.ConvexPoly
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import Control.Monad.Reader
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import Control.Lens
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@@ -78,25 +78,23 @@ mvRadar
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-> Point2 -- ^ Center of expanding circle
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-> World -> Particle -> (World, Maybe Particle)
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mvRadar 0 _ w _ = (w, Nothing)
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mvRadar x p w pt =
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( putBlips w
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, Just $ pt {_ptDraw = const pic ,_ptUpdate = mvRadar (x-1) p }
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)
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where
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pic = onLayerL [levLayer ShadowLayer, 1] $ pictures sweepPics
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putBlips = over worldEvents ( over particles (blips ++) . )
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blips = map (\bp -> blipAt bp (withAlpha (0.5*globalAlpha) red) 50) circPoints
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circPoints = mapMaybe (\wl -> uncurry collidePointCircCorrect (_wlLine wl) r p)
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$ map (over wlLine swp) (IM.elems $ wallsAlongCirc p r w)
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++ IM.elems (wallsAlongCirc p r w)
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swp (a,b) = (b,a)
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r = fromIntegral (800 - x*16)
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sweepPics = [--colHelper 0.1 $ uncurry translate p $ thickCircle r 15
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--,colHelper 0.06 $ uncurry translate p $ thickCircle (r-5) 5
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--,colHelper 0.03 $ uncurry translate p $ thickCircle (r-10) 5
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]
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globalAlpha | x > 10 = 1
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| otherwise = fromIntegral x / 10
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--colHelper y = color (withAlpha (y * globalAlpha) red)
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mvRadar x p w pt = undefined
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-- ( putBlips w
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-- , Just $ pt {_ptDraw = const pic ,_ptUpdate = mvRadar (x-1) p }
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-- )
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-- where
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-- pic = onLayerL [levLayer ShadowLayer, 1] $ pictures sweepPics
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-- putBlips = over worldEvents ( over particles (blips ++) . )
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-- blips = map (\bp -> blipAt bp (withAlpha (0.5*globalAlpha) red) 50) circPoints
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-- circPoints = mapMaybe (\wl -> uncurry collidePointCircCorrect (_wlLine wl) r p)
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-- $ map (over wlLine swp) (IM.elems $ wallsAlongCirc p r w)
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-- ++ IM.elems (wallsAlongCirc p r w)
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-- swp (a,b) = (b,a)
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-- r = fromIntegral (800 - x*16)
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-- sweepPics = [--colHelper 0.1 $ uncurry translate p $ thickCircle r 15
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-- --,colHelper 0.06 $ uncurry translate p $ thickCircle (r-5) 5
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-- --,colHelper 0.03 $ uncurry translate p $ thickCircle (r-10) 5
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-- ]
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-- globalAlpha | x > 10 = 1
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-- | otherwise = fromIntegral x / 10
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-- --colHelper y = color (withAlpha (y * globalAlpha) red)
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+1
-1
@@ -18,7 +18,7 @@ import Dodge.Default.Wall
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import Dodge.Room.Link
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import Dodge.Randify
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import Geometry
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import Geometry.ConvexPoly
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--import Geometry.ConvexPoly
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import qualified IntMapHelp as IM
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import Tile
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import Dodge.RandomHelp
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@@ -11,7 +11,7 @@ module Dodge.LevelGen.StaticWalls
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)
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where
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import Geometry
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import Geometry.ConvexPoly
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--import Geometry.ConvexPoly
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import FoldableHelp
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import Data.List.Extra
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@@ -31,8 +31,8 @@ thingsHit sp ep w
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where
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hitCrs = IM.elems
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$ IM.filter (\cr -> circOnSeg sp ep (_crPos cr) (_crRad cr))
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-- $ _creatures w
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$ creaturesAlongLine sp ep w
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$ _creatures w
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-- $ creaturesAlongLine sp ep w
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crPs = map (\cr -> ssaTriPoint ep (_crPos cr) sp (_crRad cr)) hitCrs
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crs = zip crPs (map Left hitCrs)
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hitWls = wallsOnLine sp ep (IM.unions [f b $ f a $ _znObjects $ _wallsZone w | a<-[x-1,x,x+1]
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@@ -127,6 +127,7 @@ thingsHitLongLine sp ep w
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$ _creatures w
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-- $ creaturesAlongLine sp ep w
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crPs = map (\cr -> ssaTriPoint ep (_crPos cr) sp (_crRad cr)) hitCrs
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--crPs = map _crPos hitCrs
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wls = zip (map (fromJust . hitPoint) hitWls) (map Right hitWls)
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--hitWls = wallsOnLine sp ep $ wallsAlongLine sp ep w
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hitWls = wallsOnLine sp ep $ _walls w
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+14
-125
@@ -16,16 +16,18 @@ module Geometry
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, module Geometry.Vector
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, module Geometry.Vector3D
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, module Geometry.LHS
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, module Geometry.Polygon
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) where
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import Geometry.Data
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import Geometry.Polygon
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import Geometry.Intersect
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import Geometry.Bezier
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import Geometry.Vector
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import Geometry.Vector3D
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import Geometry.LHS
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import Geometry.ConvexPoly
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--import Geometry.ConvexPoly
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import Data.Maybe
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--import Data.Maybe
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import Data.List
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-- | Return a point a distance away from a first point towards a second point.
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-- Does not go past the second point.
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@@ -33,65 +35,6 @@ alongSegBy :: Float -> Point2 -> Point2 -> Point2
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alongSegBy !x !a !b = a +.+ y *.* normalizeV (b -.- a)
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where
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y = min x $ dist a b
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-- | Given a line and a point return the point on the line closest to the
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-- point.
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closestPointOnLine
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:: Point2 -- ^ First line point.
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-> Point2 -- ^ Second line point.
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-> Point2 -- ^ Point not on line.
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-> Point2
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{-# INLINE closestPointOnLine #-}
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closestPointOnLine !a !b !p = a +.+ u *.* (b -.- a)
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where u = closestPointOnLineParam a b p
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-- | Given a line and a point return a value corresponding to how far along the
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-- line the point is.
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closestPointOnLineParam
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:: Point2 -- ^ First line point.
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-> Point2 -- ^ Second line point.
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-> Point2 -- ^ Point not on line.
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-> Float
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{-# INLINE closestPointOnLineParam #-}
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closestPointOnLineParam !a !b !p
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= (p -.- a) `dotV` (b -.- a) / (b -.- a) `dotV` (b -.- a)
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-- | Draw a rectangle based on maximal N E S W values.
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rectNESW :: Float -> Float -> Float -> Float -> [Point2]
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rectNESW !a !b !c !d = [V2 b a,V2 b c,V2 d c,V2 d a]
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-- | Draw a rectangle based on maximal N S E W values.
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rectNSEW :: Float -> Float -> Float -> Float -> [Point2]
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rectNSEW !n !s !e !w = rectNESW n e s w
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-- | Draw a rectangle based on maximal N S W E values.
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rectNSWE :: Float -> Float -> Float -> Float -> [Point2]
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rectNSWE !n !s !w !e = [V2 w n, V2 w s, V2 e s, V2 e n]
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-- | Draw a rectangle around the origin with given height and width
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rectWH :: Float -> Float -> [Point2]
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rectWH w h = rectNSWE h (-h) (-w) w
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rectXH :: Float -> Float -> [Point2]
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rectXH x h = rectNSWE h (-h) 0 x
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rectXY :: Float -> Float -> [Point2]
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rectXY x y = rectNSWE y 0 0 x
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square :: Float -> [Point2]
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square n = rectWH n n
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mirrorXAxis :: [Point2] -> [Point2]
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mirrorXAxis ps = orderPolygon $ ps ++ mapMaybe f ps
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where
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f (V2 _ 0) = Nothing
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f (V2 x y) = Just $ V2 x (-y)
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-- | Test whether a point is in a polygon or on the polygon border.
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-- Supposes the points in the
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-- polygon are listed in anticlockwise order.
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pointInOrOnPolygon :: Point2 -> [Point2] -> Bool
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pointInOrOnPolygon !p (x:xs) = all (\l -> not (uncurry isRHS l p)) $ zip (x:xs) (xs ++ [x])
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pointInOrOnPolygon _ _ = undefined
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-- | Test whether a point is strictly inside a polygon.
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-- Supposes the points in the polygon are listed in anticlockwise order.
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pointInPolygon :: Point2 -> [Point2] -> Bool
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pointInPolygon !p (x:xs) = all (\l -> uncurry isLHS l p) $ zip (x:xs) (xs ++ [x])
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pointInPolygon _ [] = False
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-- | Debug version of 'pointInPolygon'.
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errorPointInPolygon :: Int -> Point2 -> [Point2] -> Bool
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errorPointInPolygon !i !p xs
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@@ -123,55 +66,6 @@ errorClosestPointOnLineParam :: Int -> Point2 -> Point2 -> Point2 -> Float
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errorClosestPointOnLineParam _ !x! y! z
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| x == y = dist x z
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| otherwise = closestPointOnLineParam x y z
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orderPolygonAround
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:: Point2 -- ^ point to order around
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-> [Point2]
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-> [Point2]
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orderPolygonAround _ [] = []
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orderPolygonAround cen ps = sortOn (\p -> argV (p -.- cen)) ps
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orderAroundFirstReverse :: [Point2] -> [Point2]
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orderAroundFirstReverse [] = []
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orderAroundFirstReverse (a:as) = a : reverse (orderPolygonAround a as)
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orderAroundFirst :: [Point2] -> [Point2]
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orderAroundFirst [] = []
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orderAroundFirst (a:as) = a : orderPolygonAround a as
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-- | Reorder points to be anticlockwise around their center.
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orderPolygon :: [Point2] -> [Point2]
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orderPolygon [] = []
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--orderPolygon ps = orderPolygonAround (1/ fromIntegral (length ps) *.* foldr1 (+.+) ps) ps
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orderPolygon ps = orderPolygonAround (centroid ps) ps
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-- | Adds a point to a convex polygon.
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-- If the point is inside, returns the original.
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-- Points ordered anticlockwise, input not checked.
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addPointPolygon :: Point2 -> [Point2] -> [Point2]
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addPointPolygon p ps
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| pointInOrOnPolygon p ps = ps
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| otherwise = orderPolygon $ p : ps
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-- | Creates the convex hull of a set of points.
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-- Need to verify whether or not this is ordered
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convexHull :: [Point2] -> [Point2]
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convexHull (x:y:z:xs) = grahamScan $ orderAroundFirst $ sortOn (\(V2 a b) -> (b,a)) (x:y:z:xs)
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convexHull _ = error "Tried to create the convex hull of two or fewer points"
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-- | Creates the convex hull of a set of points.
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-- assumes no repetition of points: try nubbing!
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convexHullSafe :: [Point2] -> [Point2]
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--convexHullSafe (x:y:z:xs) = grahamScan $ orderAroundFirst $ sortOn (\(V2 a b) -> (b,a)) (x:y:z:xs)
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convexHullSafe (x:y:z:xs) = grahamScan $ orderAroundFirst $ sortOn (\(V2 a b) -> (b,a)) (x:y:z:xs)
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convexHullSafe _ = []
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grahamScan :: [Point2] -> [Point2]
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grahamScan = foldr push []
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where
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push point stack = grahamEliminate (point:stack)
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-- | Remove second element if top three elements are not counterclockwise.
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-- Repeat if necessary. See
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-- https://codereview.stackexchange.com/questions/206019/graham-scan-algorithm-in-haskell
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grahamEliminate :: [Point2] -> [Point2]
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grahamEliminate (x:y:z:xs)
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| not $ isLHS x y z = grahamEliminate (x:z:xs)
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grahamEliminate xs = xs
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-- | Return midpoint between two points.
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pHalf :: Point2 -> Point2 -> Point2
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@@ -302,19 +196,14 @@ ssaTriPoint' pa pb pc' bc
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= Just $ ssaTriPoint pa pb pc' bc
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-- | A potential correction of 'ssaTriPoint'.
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-- This should be tested and benchmarked.
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ssaTriPointCorrect :: Point2 -> Point2 -> Point2 -> Float -> Maybe Point2
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ssaTriPointCorrect pa pb pc' bc
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| param <= 1 && param >= 0 = Just p
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| otherwise = Nothing
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where
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p = ssaTriPoint pa pb pc' bc
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param = closestPointOnLineParam pa pc' p
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-- | Given a segment and external point, find the closest point on the segment.
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closestPointOnSeg :: Point2 -> Point2 -> Point2 -> Point2
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closestPointOnSeg segP1 segP2 p
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| errorClosestPointOnLineParam 3 segP1 segP2 p <= 0 = segP1
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| errorClosestPointOnLineParam 4 segP1 segP2 p >= 1 = segP2
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| otherwise = errorClosestPointOnLine 2 segP1 segP2 p
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--ssaTriPointCorrect :: Point2 -> Point2 -> Point2 -> Float -> Maybe Point2
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--ssaTriPointCorrect pa pb pc' bc
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-- | param <= 1 && param >= 0 = Just p
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-- | otherwise = Nothing
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-- where
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-- p = ssaTriPoint pa pb pc' bc
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-- param = closestPointOnLineParam pa pc' p
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-- | Return Just a point if it is inside a circle, Nothing otherwise.
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pointInCircle :: Point2 -> Float -> Point2 -> Maybe Point2
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pointInCircle p r c
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@@ -335,8 +224,8 @@ collidePointCirc'' :: Point2 -> Point2 -> Float -> Point2 -> Maybe (Point2,Float
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collidePointCirc'' p1 p2 rad c = (,) <$> collidePointCirc p1 p2 rad c
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<*> collidePointCirc' p1 p2 rad c
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-- | As 'collidePointCirc', but uses the supposedly correct version of ssaTriPoint.
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collidePointCircCorrect :: Point2 -> Point2 -> Float -> Point2 -> Maybe Point2
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collidePointCircCorrect p1 p2 rad c = ssaTriPointCorrect p2 c p1 rad
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--collidePointCircCorrect :: Point2 -> Point2 -> Float -> Point2 -> Maybe Point2
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--collidePointCircCorrect p1 p2 rad c = ssaTriPointCorrect p2 c p1 rad
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-- | Finds the height of a triangle using herons formula.
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-- The base is the line between the first two points.
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heron :: Point2 -> Point2 -> Point2 -> Float
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@@ -5,7 +5,7 @@ module Geometry.ConvexPoly
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, cpPoints
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, cpCen
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, cpRad
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, centroid
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-- , centroid
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, pointsToPoly
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, convexPolysOverlap
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, pointInPolyPoints
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@@ -14,9 +14,10 @@ import Geometry.Data
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import Geometry.Vector
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import Geometry.LHS
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import Geometry.Intersect
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import Geometry.Polygon
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import Control.Lens
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import qualified Control.Foldl as L
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--import qualified Control.Foldl as L
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data ConvexPoly = ConvexPoly
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{ _cpPoints :: [Point2]
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, _cpCen :: Point2
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@@ -68,7 +69,5 @@ pairPolyPointsIntersect a' b' (c':d':xs') = go c' a' b' (c':d':xs')
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go _ _ _ _ = False
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pairPolyPointsIntersect _ _ _ = False
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centroid :: Foldable t => t Point2 -> Point2
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centroid = L.fold $ (/) <$> L.Fold (+.+) (V2 0 0) id <*> L.genericLength
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makeLenses ''ConvexPoly
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@@ -1,13 +1,14 @@
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{-# LANGUAGE BangPatterns #-}
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--{-# LANGUAGE TupleSections #-}
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{-
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Testing for and finding intersection points.
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-}
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{- Testing for and finding intersection points. -}
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module Geometry.Intersect where
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import Geometry.Data
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import Geometry.Vector
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import Geometry.LHS
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import Control.Applicative
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import Data.List
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import Data.Maybe (isNothing)
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-- | If two lines intersect, return 'Just' that point.
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intersectLineLine' :: Point2 -> Point2 -> Point2 -> Point2 -> Maybe Point2
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@@ -212,3 +213,51 @@ intersectSegPolyFirst :: Point2 -> Point2 -> [Point2] -> Maybe Point2
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intersectSegPolyFirst a b xs = foldr (<|>) Nothing $ zipWith lineColl xs (tail xs ++ [head xs])
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where
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lineColl = intersectSegSeg a b
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-- | Given a line and a point return the point on the line closest to the
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-- point.
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closestPointOnLine
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:: Point2 -- ^ First line point.
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-> Point2 -- ^ Second line point.
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-> Point2 -- ^ Point not on line.
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-> Point2
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{-# INLINE closestPointOnLine #-}
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closestPointOnLine !a !b !p = a +.+ u *.* (b -.- a)
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where u = closestPointOnLineParam a b p
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-- | Given a line and a point return a value corresponding to how far along the
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-- line the point is.
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closestPointOnLineParam
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:: Point2 -- ^ First line point.
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-> Point2 -- ^ Second line point.
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-> Point2 -- ^ Point not on line.
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-> Float
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{-# INLINE closestPointOnLineParam #-}
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closestPointOnLineParam !a !b !p
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= (p -.- a) `dotV` (b -.- a) / (b -.- a) `dotV` (b -.- a)
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-- | Given a segment and external point, find the closest point on the segment.
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-- clamps to the end of the segment
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closestPointOnSeg :: Point2 -> Point2 -> Point2 -> Point2
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closestPointOnSeg segP1 segP2 p
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| closestPointOnLineParam segP1 segP2 p <= 0 = segP1
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| closestPointOnLineParam segP1 segP2 p >= 1 = segP2
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| otherwise = closestPointOnLine segP1 segP2 p
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-- | Given a segment and external point, find the closest point on the segment.
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-- does not return closest points beyond the segment
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orthogonalPointOnSeg :: Point2 -> Point2 -> Point2 -> Maybe Point2
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orthogonalPointOnSeg a b p
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| param < 0 || param > 1 = Nothing
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| otherwise = Just $ a +.+ param *.* (normalizeV $ b -.- a)
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where
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param = closestPointOnLineParam a b p
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intersectCircSeg :: Point2 -> Float -> Point2 -> Point2 -> [Point2]
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intersectCircSeg c r a b
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| y < 0 = []
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| otherwise = nub $ filter ( (< dist a b) . dist a ) [ d -.- v, d +.+ c ]
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where
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d = closestPointOnLine a b c
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x = dist d c
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y = r ** 2 - x ** 2
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z = sqrt y
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v = z *.* normalizeV (b -.- a)
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@@ -0,0 +1,102 @@
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{-# LANGUAGE BangPatterns #-}
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module Geometry.Polygon where
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import Geometry.Data
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import Geometry.LHS
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import Geometry.Vector
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import Data.Maybe
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import Data.List
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import qualified Control.Foldl as L
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-- | Draw a rectangle based on maximal N E S W values.
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rectNESW :: Float -> Float -> Float -> Float -> [Point2]
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rectNESW !a !b !c !d = [V2 b a,V2 b c,V2 d c,V2 d a]
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-- | Draw a rectangle based on maximal N S E W values.
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rectNSEW :: Float -> Float -> Float -> Float -> [Point2]
|
||||
rectNSEW !n !s !e !w = rectNESW n e s w
|
||||
-- | Draw a rectangle based on maximal N S W E values.
|
||||
rectNSWE :: Float -> Float -> Float -> Float -> [Point2]
|
||||
rectNSWE !n !s !w !e = [V2 w n, V2 w s, V2 e s, V2 e n]
|
||||
-- | Draw a rectangle around the origin with given height and width
|
||||
rectWH :: Float -> Float -> [Point2]
|
||||
rectWH w h = rectNSWE h (-h) (-w) w
|
||||
|
||||
rectXH :: Float -> Float -> [Point2]
|
||||
rectXH x h = rectNSWE h (-h) 0 x
|
||||
|
||||
rectXY :: Float -> Float -> [Point2]
|
||||
rectXY x y = rectNSWE y 0 0 x
|
||||
|
||||
square :: Float -> [Point2]
|
||||
square n = rectWH n n
|
||||
|
||||
mirrorXAxis :: [Point2] -> [Point2]
|
||||
mirrorXAxis ps = orderPolygon $ ps ++ mapMaybe f ps
|
||||
where
|
||||
f (V2 _ 0) = Nothing
|
||||
f (V2 x y) = Just $ V2 x (-y)
|
||||
|
||||
-- | Test whether a point is in a polygon or on the polygon border.
|
||||
-- Supposes the points in the
|
||||
-- polygon are listed in anticlockwise order.
|
||||
pointInOrOnPolygon :: Point2 -> [Point2] -> Bool
|
||||
pointInOrOnPolygon !p (x:xs) = all (\l -> not (uncurry isRHS l p)) $ zip (x:xs) (xs ++ [x])
|
||||
pointInOrOnPolygon _ _ = undefined
|
||||
-- | Test whether a point is strictly inside a polygon.
|
||||
-- Supposes the points in the polygon are listed in anticlockwise order.
|
||||
pointInPolygon :: Point2 -> [Point2] -> Bool
|
||||
pointInPolygon !p (x:xs) = all (\l -> uncurry isLHS l p) $ zip (x:xs) (xs ++ [x])
|
||||
pointInPolygon _ [] = False
|
||||
|
||||
orderPolygonAround
|
||||
:: Point2 -- ^ point to order around
|
||||
-> [Point2]
|
||||
-> [Point2]
|
||||
orderPolygonAround _ [] = []
|
||||
orderPolygonAround cen ps = sortOn (\p -> argV (p -.- cen)) ps
|
||||
|
||||
orderAroundFirstReverse :: [Point2] -> [Point2]
|
||||
orderAroundFirstReverse [] = []
|
||||
orderAroundFirstReverse (a:as) = a : reverse (orderPolygonAround a as)
|
||||
|
||||
orderAroundFirst :: [Point2] -> [Point2]
|
||||
orderAroundFirst [] = []
|
||||
orderAroundFirst (a:as) = a : orderPolygonAround a as
|
||||
-- | Reorder points to be anticlockwise around their center.
|
||||
orderPolygon :: [Point2] -> [Point2]
|
||||
orderPolygon [] = []
|
||||
--orderPolygon ps = orderPolygonAround (1/ fromIntegral (length ps) *.* foldr1 (+.+) ps) ps
|
||||
orderPolygon ps = orderPolygonAround (centroid ps) ps
|
||||
-- | Adds a point to a convex polygon.
|
||||
-- If the point is inside, returns the original.
|
||||
-- Points ordered anticlockwise, input not checked.
|
||||
addPointPolygon :: Point2 -> [Point2] -> [Point2]
|
||||
addPointPolygon p ps
|
||||
| pointInOrOnPolygon p ps = ps
|
||||
| otherwise = orderPolygon $ p : ps
|
||||
-- | Creates the convex hull of a set of points.
|
||||
-- Need to verify whether or not this is ordered
|
||||
convexHull :: [Point2] -> [Point2]
|
||||
convexHull (x:y:z:xs) = grahamScan $ orderAroundFirst $ sortOn (\(V2 a b) -> (b,a)) (x:y:z:xs)
|
||||
convexHull _ = error "Tried to create the convex hull of two or fewer points"
|
||||
-- | Creates the convex hull of a set of points.
|
||||
-- assumes no repetition of points: try nubbing!
|
||||
convexHullSafe :: [Point2] -> [Point2]
|
||||
--convexHullSafe (x:y:z:xs) = grahamScan $ orderAroundFirst $ sortOn (\(V2 a b) -> (b,a)) (x:y:z:xs)
|
||||
convexHullSafe (x:y:z:xs) = grahamScan $ orderAroundFirst $ sortOn (\(V2 a b) -> (b,a)) (x:y:z:xs)
|
||||
convexHullSafe _ = []
|
||||
|
||||
grahamScan :: [Point2] -> [Point2]
|
||||
grahamScan = foldr push []
|
||||
where
|
||||
push point stack = grahamEliminate (point:stack)
|
||||
-- | Remove second element if top three elements are not counterclockwise.
|
||||
-- Repeat if necessary. See
|
||||
-- https://codereview.stackexchange.com/questions/206019/graham-scan-algorithm-in-haskell
|
||||
grahamEliminate :: [Point2] -> [Point2]
|
||||
grahamEliminate (x:y:z:xs)
|
||||
| not $ isLHS x y z = grahamEliminate (x:z:xs)
|
||||
grahamEliminate xs = xs
|
||||
|
||||
centroid :: Foldable t => t Point2 -> Point2
|
||||
centroid = L.fold $ (/) <$> L.Fold (+.+) (V2 0 0) id <*> L.genericLength
|
||||
Reference in New Issue
Block a user