Add more combinators.

src/Reanimate/Monad.hs

@@ -123,6 +123,13 @@ mapF fn frame = Frame $ \d t -> do
 pauseAtEnd :: Double -> Animation -> Animation
 pauseAtEnd p a = a `andThen` pause p
 
+pauseAtBeginning :: Double -> Animation -> Animation
+pauseAtBeginning d1 a =
+    Animation d1 (freezeFrame 0 a) `before` a
+
+freezeFrame :: Double -> Animation -> Frame ()
+freezeFrame t (Animation d f) = Frame $ \_ _ -> unFrame f d t
+
 adjustSpeed :: Double -> Animation -> Animation
 adjustSpeed factor (Animation d fn) =
   Animation (d/factor) $ Frame $ \_dur t -> unFrame fn d (t*factor)

src/Reanimate/Svg.hs

@@ -518,6 +518,9 @@ withFillColorPixel color = fillColor .~ pure (ColorRef color)
 withFillOpacity :: Double -> Tree -> Tree
 withFillOpacity opacity = fillOpacity .~ Just (realToFrac opacity)
 
+withGroupOpacity :: Double -> Tree -> Tree
+withGroupOpacity opacity = groupOpacity .~ Just (realToFrac opacity)
+
 withStrokeWidth :: Number -> Tree -> Tree
 withStrokeWidth width = strokeWidth .~ pure width
 
@@ -557,6 +560,9 @@ mkDefinitions :: [Tree] -> Tree
 mkDefinitions forest = DefinitionTree $ defaultSvg
   & groupChildren .~ forest
 
+mkUse :: String -> Tree
+mkUse name = UseTree (defaultSvg & useName .~ name) Nothing
+
 mkClipPath :: String -> [Tree] -> Tree
 mkClipPath idTag forest = withId idTag $ ClipPathTree $ (defaultSvg
   & clipPathContent .~ forest)