Version 0.1.0

lib/components/cat.dart

@@ -0,0 +1,91 @@
+import 'dart:math';
+import 'dart:ui';
+
+import 'package:flame/anchor.dart';
+import 'package:flame/components/component.dart';
+import 'package:flame/sprite.dart';
+import 'package:vector_math/vector_math_64.dart';
+
+final random = Random(DateTime.now().millisecondsSinceEpoch);
+
+class Cat extends PositionComponent {
+  static const vmin = 0.1;
+  static const vmax = 150.0;
+  static const accLength = 20.0;
+  static const minDistance = 4.0;
+
+  final anchor = Anchor.bottomCenter;
+  final renderFlipX = true;
+  final axis = Vector2(-1.0, 0.0);
+
+  final catNumber = random.nextInt(7) + 1;
+
+  void Function() onBored;
+
+  bool shouldDestroy = false;
+
+  Vector2 target;
+  Vector2 position;
+  Vector2 velocity = Vector2.zero();
+  bool bored = false;
+
+  bool get isSitting => velocity.length < vmin;
+  double get width => isSitting ? 25.0 : 40.0;
+  double get height => isSitting ? 18.0 : 18.0;
+  double get x => position.x;
+  double get y => position.y;
+  double get angle => -velocity.angleToSigned(axis);
+  bool get renderFlipY => angle.abs() > 0.5 * pi;
+
+  Sprite sitting;
+  Sprite running;
+
+  Cat() {
+    sitting = Sprite('cat${catNumber}s.png');
+    running = Sprite('cat${catNumber}r.png');
+  }
+
+  void runTo(Vector2 target) {
+    bored = false;
+    this.target = target;
+
+    if (position == null) {
+      position = target;
+    }
+
+    velocity = (target - position).normalized() * vmax;
+  }
+
+  @override
+  void render(Canvas canvas) {
+    prepareCanvas(canvas);
+
+    if (isSitting) {
+      sitting.render(canvas, width: width, height: height);
+    } else {
+      running.render(canvas, width: width, height: height);
+    }
+  }
+
+  @override
+  void update(double t) {
+    if ((position - target).length < minDistance) {
+      position = target;
+      velocity.setZero();
+      if (!bored) {
+        bored = true;
+        if (onBored != null) {
+          onBored();
+        }
+      }
+    } else {
+      position += velocity * t;
+    }
+  }
+
+  @override
+  bool destroy() => shouldDestroy;
+
+  @override
+  int priority() => 10000;
+}