Merge pull request #90 from phaazon/release/4.1.1

Release/4.1.1

CHANGELOG.md

@@ -2,6 +2,7 @@
 
 <!-- vim-markdown-toc GFM -->
 
+* [4.1.1](#411)
 * [4.1](#41)
 * [4.0.3](#403)
 * [4.0.2](#402)
@@ -43,6 +44,17 @@
 
 <!-- vim-markdown-toc -->
 
+# 4.1.1
+
+> Jul 27, 2022
+
+- Internal enhancement of sampling splines by looking for control points. That brings the lookup from _O(1)_ to
+  _O(log(N))_. That is super embarassing because it should have been the default from the very first commit. Sorry
+  about that.
+- Fix hermite cubic interpolation.
+- Add support for `glam-0.21`.
+- Add support for `nalgebra-0.31`.
+
 # 4.1
 
 > Mar 28, 2022

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "splines"
-version = "4.1.0"
+version = "4.1.1"
 license = "BSD-3-Clause"
 authors = ["Dimitri Sabadie <dimitri.sabadie@gmail.com>"]
 description = "Spline interpolation made easy"
@@ -29,8 +29,8 @@ std = []
 
 [dependencies]
 cgmath = { version = ">=0.17, <0.19", optional = true }
-glam = { version = ">=0.10, <0.21", optional = true }
-nalgebra = { version = ">=0.21, <0.31", optional = true }
+glam = { version = ">=0.10, <0.22", optional = true }
+nalgebra = { version = ">=0.21, <0.32", optional = true }
 serde =  { version = "1", features = ["derive"], optional = true }
 
 [dev-dependencies]

src/interpolate.rs

@@ -127,15 +127,16 @@ macro_rules! impl_Interpolate {
         let three_t = t * 3.;
         let t2 = t * t;
         let t3 = t2 * t;
-        let two_t3 = t3 * two_t;
-        let three_t2 = t2 * three_t;
+        let two_t3 = t2 * two_t;
+        let two_t2 = t * two_t;
+        let three_t2 = t * three_t;
 
         // tangents
-        let m0 = (b.1 - x.1) / (b.0 - x.0);
-        let m1 = (y.1 - a.1) / (y.0 - a.0);
+        let m0 = (b.1 - x.1) / (b.0 - x.0) * (b.0 - a.0);
+        let m1 = (y.1 - a.1) / (y.0 - a.0) * (b.0 - a.0);
 
         a.1 * (two_t3 - three_t2 + 1.)
-          + m0 * (t3 - t2 * two_t + t)
+          + m0 * (t3 - two_t2 + t)
           + b.1 * (three_t2 - two_t3)
           + m1 * (t3 - t2)
       }
@@ -192,15 +193,16 @@ macro_rules! impl_InterpolateT {
         let three_t = t * 3.;
         let t2 = t * t;
         let t3 = t2 * t;
-        let two_t3 = t3 * two_t;
-        let three_t2 = t2 * three_t;
+        let two_t3 = t2 * two_t;
+        let two_t2 = t * two_t;
+        let three_t2 = t * three_t;
 
         // tangents
-        let m0 = (b.1 - x.1) / (Self::from(b.0 - x.0));
-        let m1 = (y.1 - a.1) / (Self::from(y.0 - a.0));
+        let m0 = (b.1 - x.1) / (Self::from(b.0 - x.0)) * (Self::from(b.0 - a.0));
+        let m1 = (y.1 - a.1) / (Self::from(y.0 - a.0)) * (Self::from(b.0 - a.0));
 
         a.1 * (two_t3 - three_t2 + 1.)
-          + m0 * (t3 - t2 * two_t + t)
+          + m0 * (t3 - two_t2 + t)
           + b.1 * (three_t2 - two_t3)
           + m1 * (t3 - t2)
       }

src/spline.rs

@@ -318,37 +318,20 @@ pub struct KeyMut<'a, T, V> {
 }
 
 // Find the lower control point corresponding to a given time.
+// It has the property to have a timestamp smaller or equal to t
 fn search_lower_cp<T, V>(cps: &[Key<T, V>], t: T) -> Option<usize>
 where
   T: PartialOrd,
 {
-  let mut i = 0;
   let len = cps.len();
-
   if len < 2 {
     return None;
   }
-
-  loop {
-    let cp = &cps[i];
-    let cp1 = &cps[i + 1];
-
-    if t >= cp1.t {
-      if i >= len - 2 {
-        return None;
-      }
-
-      i += 1;
-    } else if t < cp.t {
-      if i == 0 {
-        return None;
-      }
-
-      i -= 1;
-    } else {
-      break; // found
-    }
+  match cps.binary_search_by(|key| key.t.partial_cmp(&t).unwrap()) {
+    Err(i) if i >= len => None,
+    Err(i) if i == 0 => None,
+    Err(i) => Some(i - 1),
+    Ok(i) if i == len - 1 => None,
+    Ok(i) => Some(i),
   }
-
-  Some(i)
 }