From e0b63468fcced1a0ec245d89adfe8717ad09cc00 Mon Sep 17 00:00:00 2001
From: justin <justin.g.kruger@gmail.com>
Date: Fri, 1 Jul 2022 20:11:10 +0100
Subject: [PATCH] Redo Geometry.Zone (restrict exports, inlining)

---
 src/FoldableHelp.hs  |   1 -
 src/Geometry/Zone.hs | 208 +++----------------------------------------
 2 files changed, 10 insertions(+), 199 deletions(-)

diff --git a/src/FoldableHelp.hs b/src/FoldableHelp.hs
index 4ad1da0ae..e5dff9d2d 100644
--- a/src/FoldableHelp.hs
+++ b/src/FoldableHelp.hs
@@ -15,7 +15,6 @@ import Data.Foldable
 
 import qualified Control.Foldl as L
 
-
 -- TODO check up whether and how it is necessary to specialise this
 -- | A version of 'minimum' where the comparison is done on some extracted value.
 --   Returns Nothing if the list is empty.
diff --git a/src/Geometry/Zone.hs b/src/Geometry/Zone.hs
index 1c4a24705..68f40aa71 100644
--- a/src/Geometry/Zone.hs
+++ b/src/Geometry/Zone.hs
@@ -1,11 +1,6 @@
 --{-# LANGUAGE TupleSections #-}
 module Geometry.Zone
-    ( ddaExt
-    , ddaExt'
-    , ddaSq
-    , ddaSqStream
-    , ddaStream
-    , ddaStreamX
+    ( ddaStreamX
     , ddaStreamY
     , xIntercepts
     , yIntercepts
@@ -19,60 +14,13 @@ import Geometry.Vector
 
 import StreamingHelp
 import qualified Streaming.Prelude as S
-import Data.Foldable
-import qualified Data.IntMap.Strict as IM
-import qualified Data.IntSet as IS
---import Control.Monad
-
---foldl2'
---    :: (b -> a -> a -> b) 
---    -> b 
---    -> [a]
---    -> b
---foldl2' f s (t:ts) = fst $ foldl' g (s, t) ts
---  where
---    g (r,x) y = (f r x y,y)
---foldl2' _ s _ = s
-
---sortArguments 
---    :: Ord a 
---    => (a -> a -> b)
---    -> a -> a -> b
---sortArguments f x y
---    | x < y = f x y
---    | otherwise = f y x
---sortArgumentsReverse
---    :: Ord a 
---    => (a -> a -> [b])
---    -> a -> a -> [b]
---sortArgumentsReverse f x y
---    | x < y = f x y
---    | otherwise = reverse $ f y x
---
---intervalBounds
---    :: Float    -- ^ interval threshold
---    -> Float    -- ^ First endpoint
---    -> Float    -- ^ Second endpoint
---    -> [Float]
---intervalBounds = sortArgumentsReverse . f
---  where 
---    f r a b 
---        | x > b = [a]
---        | otherwise = (a : [x,x+r..b])
---      where
---        x = floorTo r a + r
-
---floorTo :: Float -> Float -> Float
---floorTo r x = r * (fromIntegral ((floor $ x / r) :: Int))
-
---ceilingTo :: Float -> Float -> Float
---ceilingTo r x = r * (fromIntegral ((ceiling $ x / r) :: Int))
 
 divTo :: Float -> Float -> Int
 {-# INLINE divTo #-}
 divTo s = floor . (/s)
 
 modTo :: Float -> Float -> Float
+{-# INLINE modTo #-}
 modTo s x = x - s * fromIntegral (divTo s x)
 
 --remTo :: Float -> Float -> Float
@@ -82,75 +30,13 @@ modTo s x = x - s * fromIntegral (divTo s x)
 --{-# INLINE quotTo #-}
 --quotTo s = truncate . (/s)
 
-
---flipV :: Point2 -> Point2
---{-# INLINE flipV #-}
---flipV (V2 a b) = V2 b a
-
---applyInverted 
---    :: (Point2 -> Point2 -> [Point2])
---    -> Point2 -> Point2 -> [Point2]
---applyInverted f sp@(V2 sx sy) ep@(V2 ex ey)
---    | abs (sx-ex) > abs (sy-ey) = f sp ep
---    | otherwise = map flipV $ f (flipV sp) (flipV ep)
-
 zoneOfPoint :: Float -> Point2 -> V2 Int
 {-# INLINE zoneOfPoint #-}
 zoneOfPoint s = fmap (divTo s)
 
---increasingInterval :: Int -> Int -> [Int]
---increasingInterval x y
---    | y > x = [x .. y]
---    | otherwise = [y .. x]
-
--- | Determines a "square" zone of points for a line
-ddaSq :: Float -> V2 Float -> V2 Float -> IM.IntMap IS.IntSet
-ddaSq s (V2 sx sy) (V2 ex ey) = IM.fromSet (const ys) xs
-  where
-    maxMin a b | a >= b = (a,b)
-        | otherwise = (b,a)
-    (maxx,minx) = maxMin (divTo s sx) (divTo s ex)
-    (maxy,miny) = maxMin (divTo s sy) (divTo s ey)
-    xs = IS.fromDistinctAscList [minx-1..maxx+1]
-    ys = IS.fromDistinctAscList [miny-1..maxy+1]
-
---ddaSqStream :: Monad m => Float -> V2 Float -> V2 Float -> Stream (Of (V2 Int)) m ()
---ddaSqStream s (V2 sx sy) (V2 ex ey) = S.each [V2 x y | x <- [minx..maxx], y <- [miny..maxy]]
---  where
---    maxMin a b | a >= b = (a,b)
---        | otherwise = (b,a)
---    (maxx,minx) = maxMin (divTo s sx) (divTo s ex)
---    (maxy,miny) = maxMin (divTo s sy) (divTo s ey)
-
--- | Determines which horizontal and vertical lines on a grid are crossed by a
--- line. For each adds the x-y index of the square to the right or above the
--- crossed grid line. Also adds the index of the square containing the start
--- point.
-ddaExt' :: Float -> V2 Float -> V2 Float -> IM.IntMap IS.IntSet
-ddaExt' s sp@(V2 sx sy) ep@(V2 ex ey) 
-    | x1 <= x2 = addsp . addys . IM.fromDistinctAscList $ zip [x1 .. x2] 
-                    $ map (IS.singleton . divTo s) [x1y,x1y+ydx..]
-    | otherwise = ddaExt' s ep sp
-  where
-    addsp im = let V2 x y = zoneOfPoint s sp
-        in insertXY im (x,y)
-    x1 = divTo s sx
-    x2 = divTo s ex
-    x1y = fx' sp ep $ s * fromIntegral x1
-    ydx = s * ydx' sp ep
-    addys m = add2s m ypairs 
-    y1 = divTo s sy
-    y2 = divTo s ey
-    y1x = fy' sp ep $ s * fromIntegral y1
-    y2x = fy' sp ep $ s * fromIntegral y2
-    xdy = s * xdy' sp ep
-    ypairs 
-        | y1 <= y2  = zip (map (divTo s) [y1x,y1x+xdy..])
-                         [y1 .. y2] 
-        | otherwise = zip (map (divTo s) [y2x,y2x+xdy..])
-                         [y2-1 .. y1-1] 
-ddaSqStream :: Float -> Point2 -> Point2 -> Stream (Of (V2 Int)) Identity ()
-ddaSqStream s sp ep = S.each [V2 x y | x <- makeInterval sx ex, y <- makeInterval sy ey]
+zoneOfRect :: Float -> Point2 -> Point2 -> Stream (Of (V2 Int)) Identity ()
+{-# INLINE zoneOfRect #-}
+zoneOfRect s sp ep = S.each [V2 x y | x <- makeInterval sx ex, y <- makeInterval sy ey]
   where
     V2 sx sy = zoneOfPoint s sp
     V2 ex ey = zoneOfPoint s ep
@@ -161,13 +47,12 @@ makeInterval x y
     | otherwise = [y-1..x+1]
 
 zoneInsideCirc :: Float -> Point2 -> Float -> StreamOf Int2
-zoneInsideCirc x p r = ddaSqStream x (p +.+ V2 r r) (p -.- V2 r r)
+{-# INLINE zoneInsideCirc #-}
+zoneInsideCirc x p r = zoneOfRect x (p +.+ V2 r r) (p -.- V2 r r)
 
 zoneOfSeg :: Float -> Point2 -> Point2 -> StreamOf Int2
-zoneOfSeg = ddaStream
-
-ddaStream :: Float -> Point2 -> Point2 -> Stream (Of (V2 Int)) Identity ()
-ddaStream s sp ep = S.map (zoneOfPoint s)
+{-# INLINE zoneOfSeg #-}
+zoneOfSeg s sp ep = S.map (zoneOfPoint s)
     $  S.yield sp
     <> xIntercepts s sp ep
     <> yIntercepts s sp ep
@@ -193,80 +78,7 @@ xIntercepts s (V2 sx sy) (V2 ex ey)
         | otherwise = s + sx - modTo s sx
 
 yIntercepts :: Float -> Point2 -> Point2 -> Stream (Of Point2) Identity ()
+{-# INLINE yIntercepts #-}
 yIntercepts s sp ep = S.map f $ xIntercepts s (f sp) (f ep)
   where
     f (V2 x y) = V2 y x
-
-
--- | Determines which horizontal and vertical lines on a grid are crossed by a
--- line. For each adds the x-y index of the square to the right or above the
--- crossed grid line. Also adds the index of the square containing the start
--- point.
--- Not correct, eg ddaExt 10 (V2 40 50) (V2 0 0)
-ddaExt :: Float -> V2 Float -> V2 Float -> IM.IntMap IS.IntSet
-ddaExt s sp@(V2 sx sy) ep@(V2 ex ey) 
-    | x1 <= x2 = addsp . addys . IM.fromDistinctAscList $ zip [x1 .. x2] 
-                    $ map (IS.singleton . divTo s) [x1y,x1y+ydx..]
-    | otherwise = addsp . addys . IM.fromDistinctAscList $ zip [x2-1 .. x1-1]
-                    $ map (IS.singleton . divTo s) [x2y,x2y+ydx..]
-  where
-    addsp im = let V2 x y = zoneOfPoint s sp
-        in insertXY im (x,y)
-    x1 = divTo s sx
-    x2 = divTo s ex
-    x1y = fx' sp ep $ s * fromIntegral x1
-    x2y = fx' sp ep $ s * fromIntegral x2
-    ydx = s * ydx' sp ep
-    addys m = add2s m ypairs 
-    y1 = divTo s sy
-    y2 = divTo s ey
-    y1x = fy' sp ep $ s * fromIntegral y1
-    y2x = fy' sp ep $ s * fromIntegral y2
-    xdy = s * xdy' sp ep
-    ypairs 
-        | y1 <= y2  = zip (map (divTo s) [y1x,y1x+xdy..])
-                         [y1 .. y2] 
-        | otherwise = zip (map (divTo s) [y2x,y2x+xdy..])
-                         [y2-1 .. y1-1] 
-
-ydx' :: Point2 -> Point2 -> Float
-{-# INLINE ydx' #-}
-ydx' (V2 sx sy) (V2 ex ey)
-    | sx == ex = 0
-    | otherwise = (ey - sy) / (ex - sx)
-fx' :: Point2 -> Point2 -> Float -> Float
-{-# INLINE fx' #-}
-fx' sp@(V2 sx sy) ep@(V2 _ ey) x
-    | sy == ey = sy
-    | otherwise = sy + ydx' sp ep * (x - sx)
-
-xdy' :: Point2 -> Point2 -> Float
-{-# INLINE xdy' #-}
-xdy' (V2 sx sy) (V2 ex ey)
-    | sy == ey = 0
-    | otherwise = (ex - sx) / (ey - sy)
-fy' :: Point2 -> Point2 -> Float -> Float
-{-# INLINE fy' #-}
-fy' sp@(V2 sx sy) ep@(V2 ex _) y
-    | sx == ex = sx
-    | otherwise = sx + xdy' sp ep * (y - sy)
-
-add2s :: IM.IntMap IS.IntSet -> [(Int,Int)] -> IM.IntMap IS.IntSet
-{-# INLINE add2s #-}
-add2s = foldl' 
-    (\m (k,x) -> IM.insertWith (\_ old -> IS.insert x old) k (IS.singleton x) m)
-
-insertXY :: IM.IntMap IS.IntSet -> (Int,Int) -> IM.IntMap IS.IntSet
-{-# INLINE insertXY #-}
-insertXY m (k,x) = IM.insertWith (\_ old -> IS.insert x old) k (IS.singleton x) m
-
---addV2s :: IM.IntMap IS.IntSet -> [V2 Int] -> IM.IntMap IS.IntSet
---{-# INLINE addV2s #-}
---addV2s imis = foldl' 
---    (\m (V2 k x) -> IM.insertWith (\_ old -> IS.insert x old) k (IS.singleton x) m)
---    imis
-
---pairsToIntMapSet :: [V2 Int] -> IM.IntMap IS.IntSet
---pairsToIntMapSet = foldl' 
---    (\m (V2 k x) -> IM.insertWith (\_ old -> IS.insert x old) k (IS.singleton x) m)
---    IM.empty