Start v1.0 apis (sprite, animation, box2d, etc)

lib/components/component.dart

@@ -0,0 +1,69 @@
+import 'dart:math';
+import 'dart:ui';
+
+import 'package:flame/sprite.dart';
+import 'package:flutter/painting.dart';
+
+abstract class Component {
+  void update(double t);
+
+  void render(Canvas c);
+
+  bool loaded() {
+    return true;
+  }
+
+  bool destroy() {
+    return false;
+  }
+}
+
+abstract class PositionComponent extends Component {
+  double x = 0.0, y = 0.0, angle = 0.0;
+
+  double angleBetween(PositionComponent c) {
+    return (atan2(c.x - this.x, this.y - c.y) - PI / 2) % (2 * PI);
+  }
+
+  double distance(PositionComponent c) {
+    return sqrt(pow(this.y - c.y, 2) + pow(this.x - c.x, 2));
+  }
+
+  void prepareCanvas(Canvas canvas) {
+    canvas.translate(x, y);
+    canvas.rotate(angle); // TODO: rotate around center
+  }
+}
+
+class SpriteComponent extends PositionComponent {
+  double width, height;
+  Sprite sprite;
+
+  final Paint paint = new Paint()..color = new Color(0xffffffff);
+
+  SpriteComponent.square(double size, String imagePath) : this.rectangle(size, size, imagePath);
+
+  SpriteComponent.rectangle(this.width, this.height, String imagePath) {
+    this.sprite = new Sprite(imagePath);
+  }
+
+  SpriteComponent.fromSprite(this.width, this.height, this.sprite);
+
+  @override
+  render(Canvas canvas) {
+    if (sprite.loaded()) {
+      prepareCanvas(canvas);
+      sprite.render(canvas, width, height);
+    }
+  }
+
+  @override
+  bool loaded() {
+    return this.sprite.loaded();
+  }
+
+  @override
+  void update(double t) {
+  }
+}
+