Move examples into separate executables.

examples/boundingbox.hs

@@ -0,0 +1,51 @@
+#!/usr/bin/env stack
+-- stack --resolver lts-13.14 runghc --package reanimate
+{-# LANGUAGE OverloadedStrings #-}
+module Main (main) where
+
+import           Control.Lens
+
+import           Graphics.SvgTree (Number(..),Tree)
+import           Reanimate.Driver (reanimate)
+import           Reanimate.LaTeX
+import           Reanimate.Monad
+import           Reanimate.Svg
+import           Reanimate.Signal
+
+main :: IO ()
+main = reanimate bbox
+
+bbox :: Animation
+bbox = bg `sim`
+    mapA (translate (-50) 0) bbox1 `sim`
+    mapA (translate 50 0) bbox2
+  where
+    bg = mkAnimation 0 $ emit $ mkBackground "black"
+
+bbox1 :: Animation
+bbox1 = mkAnimation 5 $ do
+    s <- getSignal signalLinear
+    emit $ mkGroup
+      [ mkBoundingBox $ rotate (360*s) svg
+      , withFillColor "white" $ rotate (360*s) svg ]
+  where
+    svg = scale 3 $ center $ latexAlign "\\sum_{k=1}^\\infty"
+
+bbox2 :: Animation
+bbox2 = autoReverse $ mkAnimation 2.5 $ do
+  s <- getSignal signalLinear
+  emit $ mkGroup
+    [ mkBoundingBox $ partialSvg s heartShape
+    , withStrokeColor "white" $ withFillOpacity 0 $ partialSvg s heartShape ]
+
+mkBoundingBox :: Tree -> Tree
+mkBoundingBox svg = withStrokeColor "red" $ withFillOpacity 0 $
+    mkRect (Num x, Num y) (Num w) (Num h)
+  where
+    (x, y, w, h) = boundingBox svg
+
+heartShape =
+    center $ rotateAroundCenter 225 $ mkPathString
+      "M0.0,40.0 v-40.0 h40.0\
+      \a20.0 20.0 90.0 0 1 0.0,40.0\
+      \a20.0 20.0 90.0 0 1 -40.0,0.0 Z"

examples/latex_basic.hs

@@ -0,0 +1,24 @@
+#!/usr/bin/env stack
+-- stack --resolver lts-13.14 runghc --package reanimate
+{-# LANGUAGE OverloadedStrings #-}
+module Main (main) where
+
+import           Control.Lens
+
+import           Graphics.SvgTree (Number(..))
+import           Reanimate.Driver (reanimate)
+import           Reanimate.LaTeX
+import           Reanimate.Monad
+import           Reanimate.Svg
+import           Reanimate.Signal
+
+main :: IO ()
+main = reanimate $ autoReverse $ mkAnimation 2 $ do
+    s <- getSignal signalLinear
+    emit $ mkGroup
+      [ mkBackground "black"
+      , withStrokeColor "white" $ withFillOpacity 0 $ withStrokeWidth (Num 0.1) text
+      , withFillColor "white" $ withFillOpacity s text ]
+  where
+    text = scale 4 $ center $ latexAlign
+      "\\sum_{k=1}^\\infty {1 \\over k^2} = {\\pi^2 \\over 6}"

examples/latex_color.hs

@@ -1,5 +1,5 @@
 #!/usr/bin/env stack
--- stack --resolver lts-12.26 runghc --package reanimate
+-- stack --resolver lts-13.14 runghc --package reanimate
 {-# LANGUAGE OverloadedStrings #-}
 module Main (main) where
 

examples/latex_draw.hs

@@ -0,0 +1,29 @@
+#!/usr/bin/env stack
+-- stack --resolver lts-13.14 runghc --package reanimate
+{-# LANGUAGE OverloadedStrings #-}
+module Main (main) where
+
+import           Control.Lens
+
+import           Graphics.SvgTree (Number(..))
+import           Reanimate.Driver (reanimate)
+import           Reanimate.LaTeX
+import           Reanimate.Monad
+import           Reanimate.Svg
+import           Reanimate.Signal
+
+main :: IO ()
+main = reanimate $
+    bg `sim` (autoReverse $ drawText `andThen` fillText)
+  where
+    bg = mkAnimation 0 $ emit (mkBackground "black")
+    msg = "\\sum_{k=1}^\\infty {1 \\over k^2} = {\\pi^2 \\over 6}"
+    glyphs = pathify $ center $ latexAlign msg
+    fillText = mkAnimation 1 $ do
+      s <- getSignal signalLinear
+      emit $ scale 5 $ withFillColor "white" $ withFillOpacity s glyphs
+    drawText = mkAnimation 2 $ do
+      s <- getSignal signalLinear
+      emit $ scale 5 $
+        withStrokeColor "white" $ withFillOpacity 0 $ withStrokeWidth (Num 0.1) $
+          partialSvg s glyphs

examples/sunflower.hs

@@ -0,0 +1,53 @@
+#!/usr/bin/env stack
+-- stack --resolver lts-13.14 runghc --package reanimate
+{-# LANGUAGE OverloadedStrings #-}
+module Main (main) where
+
+import           Codec.Picture.Types
+import qualified Data.Colour.Palette.BrewerSet as D
+import qualified Diagrams.Backend.SVG          as D
+import           Diagrams.Prelude              hiding (Animation, boundingBox,
+                                                center, circle, duration,
+                                                fontSize, rotate, scale,
+                                                translate)
+import qualified Diagrams.Prelude              as D
+import qualified Diagrams.TwoD.Path.LSystem    as D
+import           Graphics.SvgTree              (Number (..))
+import           Graphics.SvgTree              as S
+import           Linear.V2
+import           Reanimate.Diagrams
+import           Reanimate.Driver              (reanimate)
+import           Reanimate.LaTeX
+import           Reanimate.Monad
+import           Reanimate.Signal
+import           Reanimate.Svg
+
+
+main :: IO ()
+main = reanimate $ mkAnimation 10 $ do
+    n <- getSignal $ signalFromTo 1 500 signalLinear
+    rot <- getSignal $ signalFromTo 0 45 signalLinear
+    emit $ mkBackground "black"
+    emit $ rotate rot $ translate (-320/2) (-180/2)
+      (dSvg $ round n)
+  where
+    cached = [ dSvg n | n <- [0..]]
+    dSvg n = renderDiagram $ withEnvelope (D.rect 320 180 :: SvgDiagram) $
+      D.scale 5 $ sunflower n
+
+    mkCoords :: [P2 Double]
+    mkCoords =[coord (fromIntegral i) | i <- [1..]]
+      where
+        coord m = p2 $ fromPolar (sqrt m) (2.4 * m)
+        fromPolar r theta = (r * cos theta, r * sin theta)
+
+    floret :: Double -> SvgDiagram
+    floret r = D.circle 0.6 # lw none # fc (colors !! n)
+      where
+        n = floor (1.4 * sqrt r) `mod` 10
+        colors = black : (reverse $ D.brewerSet D.YlOrBr 9)
+
+    sunflower :: Int ->  SvgDiagram
+    sunflower n = frame 4 $ position $ take n $ zip mkCoords florets
+      where
+        florets = [ floret (sqrt (fromIntegral i)) | i <- [1 ..]]

examples/tangent_and_normal.hs

@@ -0,0 +1,63 @@
+#!/usr/bin/env stack
+-- stack --resolver lts-13.14 runghc --package reanimate
+{-# LANGUAGE OverloadedStrings #-}
+module Main (main) where
+
+import           Codec.Picture.Types
+import qualified Data.Colour.Palette.BrewerSet as D
+import qualified Diagrams.Backend.SVG          as D
+import           Diagrams.Prelude              hiding (Animation, boundingBox,
+                                                center, circle, duration,
+                                                fontSize, rotate, scale,
+                                                translate)
+import qualified Diagrams.Prelude              as D
+import qualified Diagrams.TwoD.Path.LSystem    as D
+import           Graphics.SvgTree              (Number (..))
+import           Graphics.SvgTree              as S
+import           Linear.V2
+import           Reanimate.Diagrams
+import           Reanimate.Driver              (reanimate)
+import           Reanimate.LaTeX
+import           Reanimate.Monad
+import           Reanimate.Signal
+import           Reanimate.Svg
+
+
+main :: IO ()
+main = reanimate $ mkAnimation 5 $ do
+    s <- oscillate $ getSignal $ signalCurve 2
+    emit $ mkBackground "black"
+    emit $ translate (-320/2) (-180/2) $ withStrokeColor "white" $
+      renderDiagram $
+        withEnvelope (D.rect 320 180 :: SvgDiagram) $
+        D.scale 50 $ D.translate (V2 (-2) (-0.75)) $ dia s
+  where
+    dia param =
+        frame 0.5 $ lc white $
+        mconcat
+          [ lc green $ rightAngleSquare
+          , tangentLine
+          , baselineText "tangent" # D.translate tangentVector
+          , normalLine
+          , topLeftText "normal" # D.translate (-normalVector)
+          ] # moveTo pt # D.fontSize large
+          <> strokeLocTrail spline
+      where
+        pts = map p2 [(0,0), (1,1), (2,1), (3,0), (3.5,0)]
+
+        spline :: Located (Trail V2 Double)
+        spline = cubicSpline False pts
+
+        pt = atParam spline param
+        tangentVector ::  V2 Double
+        tangentVector = D.normalize $ tangentAtParam spline param
+        normalVector = D.normalize $ normalAtParam spline param
+
+        symmetricLine :: V2 Double -> SvgDiagram
+        symmetricLine v = fromOffsets [2 *^ v] # D.center
+        tangentLine :: SvgDiagram
+        tangentLine = symmetricLine tangentVector
+        normalLine = symmetricLine normalVector
+
+        rightAngleSquare :: SvgDiagram
+        rightAngleSquare = square 0.1 # alignBL # D.rotate (signedAngleBetween tangentVector unitX)