From 00f90559d46644989d44337e8c80bbcfa9ef9d34 Mon Sep 17 00:00:00 2001
From: Hennadii Chernyshchyk <genaloner@gmail.com>
Date: Fri, 25 Oct 2024 03:03:42 +0300
Subject: [PATCH] Fix `SmoothDelta` modifier

---
 CHANGELOG.md                                  |  4 ++++
 .../input_modifier/smooth_delta.rs            | 23 +++++++------------
 2 files changed, 12 insertions(+), 15 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index bf1f542..a195d23 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Logging for binding.
 
+### Fixed
+
+- `SmoothDelta` modifier.
+
 ### Changed
 
 - Remove world access from conditions and modifiers. This means that you no longer can write game-specific conditions or modifiers. But it's much nicer (and faster) to just do it in observers instead.
diff --git a/src/input_context/input_modifier/smooth_delta.rs b/src/input_context/input_modifier/smooth_delta.rs
index 8f71587..a322f71 100644
--- a/src/input_context/input_modifier/smooth_delta.rs
+++ b/src/input_context/input_modifier/smooth_delta.rs
@@ -18,9 +18,7 @@ pub struct SmoothDelta {
     /// Multiplier for delta time.
     pub speed: f32,
 
-    old_value: Vec3,
-
-    value_delta: Vec3,
+    prev_value: Vec3,
 }
 
 impl SmoothDelta {
@@ -29,8 +27,7 @@ impl SmoothDelta {
         Self {
             kind: kind.into(),
             speed,
-            old_value: Default::default(),
-            value_delta: Default::default(),
+            prev_value: Default::default(),
         }
     }
 }
@@ -42,21 +39,17 @@ impl InputModifier for SmoothDelta {
             return self.apply(time, value.into());
         }
 
-        let dim = value.dim();
-        let value = value.as_axis3d();
-        let target_value_delta = (value - self.old_value).normalize_or_zero();
-        self.old_value = value;
-
-        let alpha = (time.delta_seconds() * self.speed).min(1.0);
-        self.value_delta = match self.kind {
+        let alpha = time.delta_seconds() * self.speed;
+        let smoothed = match self.kind {
             SmoothKind::EaseFunction(ease_function) => {
                 let ease_alpha = alpha.calc(ease_function);
-                self.value_delta.lerp(target_value_delta, ease_alpha)
+                self.prev_value.lerp(value.as_axis3d(), ease_alpha)
             }
-            SmoothKind::Linear => self.value_delta.lerp(target_value_delta, alpha),
+            SmoothKind::Linear => self.prev_value.lerp(value.as_axis3d(), alpha),
         };
+        self.prev_value = smoothed;
 
-        ActionValue::Axis3D(self.value_delta).convert(dim)
+        ActionValue::Axis3D(smoothed).convert(value.dim())
     }
 }