From 65f2a5d60b12ed127a99497e713f0257ad7b7c03 Mon Sep 17 00:00:00 2001
From: Jonas Wanke <contact@jonas-wanke.com>
Date: Sat, 30 Dec 2023 11:02:32 +0100
Subject: [PATCH] Interpolate colors in Oklab space i/o HSV

---
 example/pubspec.lock       | 42 +++++++++++++++++++++++++++++++++-----
 lib/src/app_bar/state.dart |  9 ++++++--
 pubspec.yaml               |  1 +
 3 files changed, 45 insertions(+), 7 deletions(-)

diff --git a/example/pubspec.lock b/example/pubspec.lock
index 5a4b0a6..94408c4 100644
--- a/example/pubspec.lock
+++ b/example/pubspec.lock
@@ -105,6 +105,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "3.0.0"
+  color_models:
+    dependency: transitive
+    description:
+      name: color_models
+      sha256: "3683f0a461570161ca22b7d3e1765b2ce2bce3534db14e00d5ee458d0287abac"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.3.3"
   convert:
     dependency: transitive
     description:
@@ -215,6 +223,14 @@ packages:
     description: flutter
     source: sdk
     version: "0.0.0"
+  flutter_color_models:
+    dependency: transitive
+    description:
+      name: flutter_color_models
+      sha256: "8454198ba9a82e533452d0764f1df3d6c3ccc2b33e18eb1f2fedc7ae4a5c43be"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.3.3+2"
   flutter_lints:
     dependency: transitive
     description:
@@ -307,10 +323,18 @@ packages:
     dependency: transitive
     description:
       name: meta
-      sha256: "3c74dbf8763d36539f114c799d8a2d87343b5067e9d796ca22b5eb8437090ee3"
+      sha256: a6e590c838b18133bb482a2745ad77c5bb7715fb0451209e1a7567d416678b8e
       url: "https://pub.dev"
     source: hosted
-    version: "1.9.1"
+    version: "1.10.0"
+  num_utilities:
+    dependency: transitive
+    description:
+      name: num_utilities
+      sha256: "170695bcafd17a19ee3a060325e7e10fb35bb878c8bcb3e6f5691dde1462c0ae"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.0.5"
   oxidized:
     dependency: transitive
     description:
@@ -359,6 +383,14 @@ packages:
       url: "https://pub.dev"
     source: hosted
     version: "0.2.2"
+  powers:
+    dependency: transitive
+    description:
+      name: powers
+      sha256: "389ba222d4264655ecd3ffa461921bc707a07e4597b98831d21dd516eed6f496"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.0.0+2"
   pub_semver:
     dependency: transitive
     description:
@@ -505,10 +537,10 @@ packages:
     dependency: transitive
     description:
       name: web
-      sha256: dc8ccd225a2005c1be616fe02951e2e342092edf968cf0844220383757ef8f10
+      sha256: afe077240a270dcfd2aafe77602b4113645af95d0ad31128cc02bce5ac5d5152
       url: "https://pub.dev"
     source: hosted
-    version: "0.1.4-beta"
+    version: "0.3.0"
   web_socket_channel:
     dependency: transitive
     description:
@@ -534,5 +566,5 @@ packages:
     source: hosted
     version: "3.1.2"
 sdks:
-  dart: ">=3.1.0-185.0.dev <4.0.0"
+  dart: ">=3.2.0-194.0.dev <4.0.0"
   flutter: ">=3.10.0"
diff --git a/lib/src/app_bar/state.dart b/lib/src/app_bar/state.dart
index 63998e5..cd6083f 100644
--- a/lib/src/app_bar/state.dart
+++ b/lib/src/app_bar/state.dart
@@ -3,6 +3,7 @@ import 'dart:ui';
 import 'package:black_hole_flutter/black_hole_flutter.dart';
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
+import 'package:flutter_color_models/flutter_color_models.dart';
 
 import 'leading.dart';
 
@@ -55,8 +56,12 @@ class MorphingState {
   SystemUiOverlayStyle get systemOverlayStyle =>
       t < 0.5 ? parent.systemOverlayStyle : child.systemOverlayStyle;
 
-  static Color _lerpColor(Color a, Color b, double t) =>
-      HSVColor.lerp(HSVColor.fromColor(a), HSVColor.fromColor(b), t)!.toColor();
+  /// Interpolate between colors in Oklab space.
+  static Color _lerpColor(Color a, Color b, double t) {
+    return OklabColor.fromColor(a)
+        .interpolate(OklabColor.fromColor(b), t)
+        .toColor();
+  }
 }
 
 @immutable
diff --git a/pubspec.yaml b/pubspec.yaml
index a75f93a..511f230 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -15,6 +15,7 @@ dependencies:
   collection: ^1.15.0
   flutter:
     sdk: flutter
+  flutter_color_models: ^1.3.3+2
   list_diff: ^2.0.0
 
 dev_dependencies: