animation: Tweak clamped duration logic

2 files changed, 13 insertions, 7 deletions

diff --git a/src/animation/mod.rs b/src/animation/mod.rs
index a68b3342..0a972ab8 100644
--- a/src/animation/mod.rs
+++ b/src/animation/mod.rs
@@ -17,6 +17,8 @@ pub struct Animation {
     to: f64,
     duration: Duration,
     /// Time until the animation first reaches `to`.
+    ///
+    /// Best effort; not always exactly precise.
     clamped_duration: Duration,
     start_time: Duration,
     current_time: Duration,
@@ -117,12 +119,14 @@ impl Animation {
     }
 
     pub fn spring(spring: Spring) -> Self {
+        let _span = tracy_client::span!("Animation::spring");
+
         // FIXME: ideally we shouldn't use current time here because animations started within the
         // same frame cycle should have the same start time to be synchronized.
         let now = get_monotonic_time();
 
         let duration = spring.duration();
-        let clamped_duration = spring.clamped_duration();
+        let clamped_duration = spring.clamped_duration().unwrap_or(duration);
         let kind = Kind::Spring(spring);
 
         Self {
@@ -266,6 +270,8 @@ impl Animation {
     }
 
     /// Returns a value that stops at the target value after first reaching it.
+    ///
+    /// Best effort; not always exactly precise.
     pub fn clamped_value(&self) -> f64 {
         if self.is_clamped_done() {
             return self.to;
diff --git a/src/animation/spring.rs b/src/animation/spring.rs
index 506b01a3..226d7cc2 100644
--- a/src/animation/spring.rs
+++ b/src/animation/spring.rs
@@ -97,15 +97,15 @@ impl Spring {
     }
 
     /// Computes and returns the duration until the spring reaches its target position.
-    pub fn clamped_duration(&self) -> Duration {
+    pub fn clamped_duration(&self) -> Option<Duration> {
         let beta = self.params.damping / (2. * self.params.mass);
 
         if beta.abs() <= f64::EPSILON || beta < 0. {
-            return Duration::MAX;
+            return Some(Duration::MAX);
         }
 
         if (self.to - self.from).abs() <= f64::EPSILON {
-            return Duration::ZERO;
+            return Some(Duration::ZERO);
         }
 
         // The first frame is not that important and we avoid finding the trivial 0 for in-place
@@ -116,15 +116,15 @@ impl Spring {
         while (self.to - self.from > f64::EPSILON && self.to - y > self.params.epsilon)
             || (self.from - self.to > f64::EPSILON && y - self.to > self.params.epsilon)
         {
-            if i > 1000 {
-                return Duration::ZERO;
+            if i > 3000 {
+                return None;
             }
 
             i += 1;
             y = self.oscillate(f64::from(i) / 1000.);
         }
 
-        Duration::from_millis(u64::from(i))
+        Some(Duration::from_millis(u64::from(i)))
     }
 
     /// Returns the spring position at a given time in seconds.