perf: schedule engine frames at the composition frame rate (throttled ticker)

CHANGELOG.md

@@ -1,3 +1,6 @@
+## 3.6.0
+- Reduce CPU usage by only scheduling animation frames at the composition frame rate instead of on every vsync
+
 ## 3.5.2
 - Fix a CanvasKit stack overflow when drawing animated Trim Paths on Flutter web
 

example/android/app/build.gradle

@@ -1,6 +1,6 @@
 plugins {
     id "com.android.application"
-    id "kotlin-android"
+    id "org.jetbrains.kotlin.android"
     id "dev.flutter.flutter-gradle-plugin"
 }
 

example/android/build.gradle

@@ -1,16 +1,3 @@
-buildscript {
-    ext.kotlin_version = '1.7.10'
-    repositories {
-        google()
-        mavenCentral()
-    }
-
-    dependencies {
-        classpath 'com.android.tools.build:gradle:7.3.0'
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
-    }
-}
-
 allprojects {
     repositories {
         google()

example/android/gradle.properties

@@ -1,3 +1,7 @@
 org.gradle.jvmargs=-Xmx1536M
 android.useAndroidX=true
 android.enableJetifier=true
+# This builtInKotlin flag was added automatically by Flutter migrator
+android.builtInKotlin=false
+# This newDsl flag was added automatically by Flutter migrator
+android.newDsl=false

example/android/gradle/wrapper/gradle-wrapper.properties

@@ -2,4 +2,4 @@ distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.5-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.7-all.zip

example/android/settings.gradle

@@ -5,16 +5,21 @@ pluginManagement {
         def flutterSdkPath = properties.getProperty("flutter.sdk")
         assert flutterSdkPath != null, "flutter.sdk not set in local.properties"
         return flutterSdkPath
-    }
-    settings.ext.flutterSdkPath = flutterSdkPath()
+    }()
 
-    includeBuild("${settings.ext.flutterSdkPath}/packages/flutter_tools/gradle")
+    includeBuild("$flutterSdkPath/packages/flutter_tools/gradle")
 
-    plugins {
-        id "dev.flutter.flutter-gradle-plugin" version "1.0.0" apply false
+    repositories {
+        google()
+        mavenCentral()
+        gradlePluginPortal()
     }
 }
 
-include ":app"
+plugins {
+    id "dev.flutter.flutter-plugin-loader" version "1.0.0"
+    id "com.android.application" version "8.6.0" apply false
+    id "org.jetbrains.kotlin.android" version "1.8.22" apply false
+}
 
-apply from: "${settings.ext.flutterSdkPath}/packages/flutter_tools/gradle/app_plugin_loader.gradle"
+include ":app"

example/lib/bench_main.dart

@@ -0,0 +1,40 @@
+import 'dart:async';
+import 'package:flutter/material.dart';
+import 'package:flutter/scheduler.dart';
+import 'package:lottie/lottie.dart';
+
+void main() {
+  WidgetsFlutterBinding.ensureInitialized();
+  var frames = 0;
+  SchedulerBinding.instance.addTimingsCallback((timings) {
+    frames += timings.length;
+  });
+  Timer.periodic(const Duration(seconds: 1), (_) {
+    // ignore: avoid_print
+    print('frames/s: $frames');
+    frames = 0;
+  });
+  runApp(const BenchApp());
+}
+
+class BenchApp extends StatelessWidget {
+  const BenchApp({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      home: Scaffold(
+        body: ListView(
+          children: [
+            Lottie.asset(
+              const String.fromEnvironment(
+                'ASSET',
+                defaultValue: 'assets/LottieLogo1.json',
+              ),
+            ),
+          ],
+        ),
+      ),
+    );
+  }
+}