Merge pull request #3016 from vlidholt/linedrawing

Initial version of Fancy line drawer demo

examples/material_gallery/flutter.yaml

@@ -24,3 +24,4 @@ assets:
   - packages/flutter_gallery_assets/jumpingjack.json
   - packages/flutter_gallery_assets/jumpingjack.png
   - packages/flutter_gallery_assets/grain.png
+  - packages/flutter_gallery_assets/fancylines.png

examples/material_gallery/lib/demo/drawing_demo.dart

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+import 'dart:async';
+
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+
+import 'package:flutter_sprites/flutter_sprites.dart';
+
+class DrawingDemo extends StatefulWidget {
+  @override
+  _DrawingDemoState createState() => new _DrawingDemoState();
+}
+
+class _DrawingDemoState extends State<DrawingDemo> {
+  _LineDrawingNode _rootNode;
+  ImageMap _images;
+
+  Future<Null> _loadAssets(AssetBundle bundle) async {
+    _images = new ImageMap(bundle);
+    await _images.load(<String>[
+      'packages/flutter_gallery_assets/fancylines.png'
+    ]);
+  }
+
+  @override
+  void initState() {
+    super.initState();
+    _loadAssets(DefaultAssetBundle.of(context)).then((_) {
+      setState(() {
+        _rootNode = new _LineDrawingNode(_images);
+      });
+    });
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    Widget body;
+    if (_rootNode == null) {
+      body = new Center(
+        child: new CircularProgressIndicator()
+      );
+    } else {
+      body = new SpriteWidget(_rootNode, SpriteBoxTransformMode.nativePoints);
+    }
+
+    return new Scaffold(
+      appBar: new AppBar(
+        title: new Text("Fancy Lines")
+      ),
+      body: body
+    );
+  }
+}
+
+class _LineDrawingNode extends NodeWithSize {
+  _LineDrawingNode(this._images) : super(const Size(1024.0, 1024.0)) {
+    userInteractionEnabled = true;
+  }
+
+  final ImageMap _images;
+  EffectLine _currentLine;
+
+  @override
+  bool handleEvent(SpriteBoxEvent event) {
+    if (event.type == PointerDownEvent) {
+      _currentLine = new EffectLine(
+        texture: new Texture(_images['packages/flutter_gallery_assets/fancylines.png']),
+        colorSequence: new ColorSequence.fromStartAndEndColor(Colors.purple[500], Colors.purple[600]),
+        fadeAfterDelay: 3.0,
+        fadeDuration: 1.0
+      );
+      _currentLine.addPoint(event.boxPosition);
+      addChild(_currentLine);
+    } else if (event.type == PointerMoveEvent) {
+      _currentLine.addPoint(event.boxPosition);
+    }
+
+    return true;
+  }
+}

examples/material_gallery/lib/gallery/home.dart

@@ -16,6 +16,7 @@ import '../demo/chip_demo.dart';
 import '../demo/date_picker_demo.dart';
 import '../demo/dialog_demo.dart';
 import '../demo/drop_down_demo.dart';
+import '../demo/drawing_demo.dart';
 import '../demo/fitness_demo.dart';
 import '../demo/flexible_space_demo.dart';
 import '../demo/grid_list_demo.dart';
@@ -80,6 +81,7 @@ class GalleryHomeState extends State<GalleryHome> {
             children: <Widget>[
               new GalleryItem(title: "Weather", builder: () => new WeatherDemo()),
               new GalleryItem(title: "Fitness", builder: () => new FitnessDemo()),
+              new GalleryItem(title: "Fancy Lines", builder: () => new DrawingDemo()),
             ]
           ),
           new TwoLevelSublist(

examples/material_gallery/pubspec.yaml

@@ -7,4 +7,4 @@ dependencies:
     path: ../../packages/flutter
   flutter_sprites:
     path: ../../packages/flutter_sprites
-  flutter_gallery_assets: '0.0.12'
+  flutter_gallery_assets: '0.0.13'

packages/flutter_sprites/lib/src/sprite_box.dart

@@ -228,7 +228,7 @@ class SpriteBox extends RenderBox {
       // Check if this event should be dispatched
       if (node.handleMultiplePointers || event.pointer == node._handlingPointer) {
         // Dispatch event
-        bool consumedEvent = node.handleEvent(new SpriteBoxEvent(event.position, event.runtimeType, event.pointer));
+        bool consumedEvent = node.handleEvent(new SpriteBoxEvent(globalToLocal(event.position), event.runtimeType, event.pointer));
         if (consumedEvent == null || consumedEvent)
           break;
       }