Adding Animation reversed (#66)

* Adding Animation#reversed

* Updating CHANGELOG

* PR suggestions

CHANGELOG.md

@@ -1,5 +1,6 @@
 ## [next]
 - Svg support
+- Adding `Animation#reversed` allowing a new reversed animation to be created from an existing animation.
 
 ## [0.10.2]
 - Fixed some warnings and formatting

doc/examples/animations/.gitignore

@@ -0,0 +1,70 @@
+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.buildlog/
+.history
+.svn/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# Visual Studio Code related
+.vscode/
+
+# Flutter/Dart/Pub related
+**/doc/api/
+.dart_tool/
+.flutter-plugins
+.packages
+.pub-cache/
+.pub/
+/build/
+
+# Android related
+**/android/**/gradle-wrapper.jar
+**/android/.gradle
+**/android/captures/
+**/android/gradlew
+**/android/gradlew.bat
+**/android/local.properties
+**/android/**/GeneratedPluginRegistrant.java
+
+# iOS/XCode related
+**/ios/**/*.mode1v3
+**/ios/**/*.mode2v3
+**/ios/**/*.moved-aside
+**/ios/**/*.pbxuser
+**/ios/**/*.perspectivev3
+**/ios/**/*sync/
+**/ios/**/.sconsign.dblite
+**/ios/**/.tags*
+**/ios/**/.vagrant/
+**/ios/**/DerivedData/
+**/ios/**/Icon?
+**/ios/**/Pods/
+**/ios/**/.symlinks/
+**/ios/**/profile
+**/ios/**/xcuserdata
+**/ios/.generated/
+**/ios/Flutter/App.framework
+**/ios/Flutter/Flutter.framework
+**/ios/Flutter/Generated.xcconfig
+**/ios/Flutter/app.flx
+**/ios/Flutter/app.zip
+**/ios/Flutter/flutter_assets/
+**/ios/ServiceDefinitions.json
+**/ios/Runner/GeneratedPluginRegistrant.*
+
+# Exceptions to above rules.
+!**/ios/**/default.mode1v3
+!**/ios/**/default.mode2v3
+!**/ios/**/default.pbxuser
+!**/ios/**/default.perspectivev3
+!/packages/flutter_tools/test/data/dart_dependencies_test/**/.packages

doc/examples/animations/.metadata

@@ -0,0 +1,10 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: 7fc14a55af64462763d28abfb4e610086c6e0f39
+  channel: dev
+
+project_type: app

doc/examples/animations/README.md

@@ -0,0 +1,3 @@
+# animations
+
+A Flame game showcasing how to use animations

doc/examples/animations/lib/main.dart

@@ -0,0 +1,31 @@
+import 'package:flame/flame.dart';
+import 'package:flame/game.dart';
+import 'package:flame/animation.dart' as FlameAnimation;
+import 'package:flame/components/animation_component.dart';
+import 'package:flutter/material.dart';
+
+void main() => runApp(MyGame().widget);
+
+class MyGame extends BaseGame {
+  MyGame() {
+    _start();
+  }
+
+  _start() async {
+    Size size = await Flame.util.initialDimensions();
+
+    final animation = await FlameAnimation.Animation.sequenced('chopper.png', 4, textureWidth: 48, textureHeight: 48, stepTime: 0.15);
+
+    final animationComponent = AnimationComponent(100, 100, animation);
+    animationComponent.x = size.width / 2 - 100;
+    animationComponent.y = 100;
+
+    final reversedAnimationComponent = AnimationComponent(100, 100, animation.reversed());
+    reversedAnimationComponent.x = size.width / 2;
+    reversedAnimationComponent.y = 100;
+
+    add(animationComponent);
+    add(reversedAnimationComponent);
+  }
+}
+

doc/examples/animations/pubspec.yaml

@@ -0,0 +1,21 @@
+name: animations
+description: Flame sample game showcasing animations features
+
+version: 1.0.0+1
+
+environment:
+  sdk: ">=2.1.0 <3.0.0"
+
+dependencies:
+  flutter:
+    sdk: flutter
+  flame:
+      path: ../../../
+
+dev_dependencies:
+  flutter_test:
+    sdk: flutter
+
+flutter:
+  assets:
+    - assets/images/chopper.png

lib/animation.dart

@@ -40,12 +40,12 @@ class Animation {
   /// Creates an animation based on the parameters.
   ///
   /// All frames have the same [stepTime].
-  Animation.spriteList(List<Sprite> sprites, {double stepTime, this.loop}) {
+  Animation.spriteList(List<Sprite> sprites, {double stepTime, this.loop = true}) {
     this.frames = sprites.map((s) => Frame(s, stepTime)).toList();
   }
 
   /// Creates an animation given a list of frames.
-  Animation(this.frames, {this.loop});
+  Animation(this.frames, {this.loop = true});
 
   /// Automatically creates a sequenced animation, that is, an animation based on a sprite sheet.
   ///
@@ -200,6 +200,11 @@ class Animation {
     }
   }
 
+  /// Returns a new Animation based on this animation, but with its frames in reversed order
+  Animation reversed() {
+    return Animation(this.frames.reversed.toList(), loop: this.loop);
+  }
+
   /// Wether all sprites composing this animation are loaded.
   bool loaded() {
     return frames.every((frame) => frame.sprite.loaded());