smoothie 0.3 → 0.3.1

raw patch · 5 files changed

+36/−10 lines, 5 files

Files

• CHANGELOG.md +6/−0
• smoothie.cabal +1/−1
• src/Data/Spline.hs +1/−5
• src/Data/Spline/Curve.hs +3/−1
• src/Data/Spline/Key.hs +25/−3

@@ -1,3 +1,9 @@+## 0.3.1++- Fixed sampling implementation.+- Updated documentation.+- Added normalizeSampling.+ ## 0.3  - Added Bézier interpolation mode.

@@ -1,5 +1,5 @@ name:                smoothie
-version:             0.3
+version:             0.3.1
 synopsis:            Smooth curves via several splines and polynomials.
 description:         This package exports several splines and curves you can use
                      to interpolate points in between.

@@ -7,12 +7,8 @@ -- Stability   : experimental -- Portability : portable ----- A @Spline s a@ represents a curve in which 'a' is very likely to be+-- A @Spline a s@ represents a curve in which 'a' is very likely to be -- 'Additive' (see "linear") and 's' is the sampling type.------ The library exports two useful functions: 'spline' and 'smooth'. The former--- enables you to create splines while the latter enables you to sample from--- them using their control points. ----------------------------------------------------------------------------  module Data.Spline (

@@ -60,7 +60,9 @@ sample :: (Additive a,Floating s,Ord s) => Spline a s -> s -> Maybe (a s) sample (Spline keys sampler) at = do   i <- bsearchLower (\k -> compare at (sampler $ keyValue k)) keys-  interpolateKeys at <$> keys !? i <*> keys !? (i + 1)+  k0 <- keys !? i+  k1 <- keys !? (i + 1)+  pure $ interpolateKeys (normalizeSampling sampler at k0 k1) k0 k1  -- Helper binary search that searches the ceiling index for the -- value to be searched according to the predicate.

@@ -14,6 +14,7 @@   , keyValue     -- * interpolation   , interpolateKeys+  , normalizeSampling   ) where  import Linear@@ -33,8 +34,8 @@ -- key. -- -- @Bezier l v r@ represents a cubic Bezier interpolation, where 'l' refers--- to the input – left – normal of the key and 'r' is the--- output – right – normal of the key.+-- to the input – left – tangent of the key and 'r' is the+-- output – right – tangent of the key. data Key a   = Hold a   | Linear a@@ -81,7 +82,7 @@     b = keyValue end  -- @interpolateBezier s k0 r0 l1 k1@ performs a Bezier interpolation--- between keys 'k0' and 'k1' using their respectives right and left handles.+-- between keys 'k0' and 'k1' using their respectives right and left tangents. interpolateBezier :: (Additive a,Floating s)                   => s                   -> a s@@ -93,3 +94,24 @@   where     u = k0 ^+^ (r0 ^-^ k0) ^* s     v = l1 ^+^ (k1 ^-^ l1) ^* s++-- |Normalize a sampling value by clamping and scaling it between two keys.+--+-- The following laws should be satisfied in order to get a coherent output:+--+-- @+--   sampler :: a s -> s+--+--   sampler (keyValue k1) <= s >= sampler (keyValue k0)+--   0 <= normalizeSampling sampler s k0 k1 <= 1+-- @+normalizeSampling :: (Fractional s)+                  => (a s -> s)+                  -> s+                  -> Key (a s)+                  -> Key (a s)+                  -> s+normalizeSampling sampler s k0 k1 = (s - s0) / (s1 - s0)+  where+    s0 = sampler (keyValue k0)+    s1 = sampler (keyValue k1)