From 266e85ce7cb75d71fc29717ece6d0552b392d630 Mon Sep 17 00:00:00 2001
From: feroult <feroult@gmail.com>
Date: Tue, 14 Nov 2017 14:34:21 -0200
Subject: [PATCH] box fit for sprite components

---
 lib/component.dart | 38 +++++++++++++++++++++++++++-----------
 1 file changed, 27 insertions(+), 11 deletions(-)

diff --git a/lib/component.dart b/lib/component.dart
index faf3e3128..4fe43c758 100644
--- a/lib/component.dart
+++ b/lib/component.dart
@@ -1,20 +1,25 @@
-import 'dart:ui';
 import 'dart:math';
+import 'dart:ui';
+
+import 'package:flutter/painting.dart';
 
 import 'flame.dart';
 
 abstract class Component {
 
   void update(double t);
+
   void render(Canvas c);
 
 }
 
 abstract class PositionComponent extends Component {
-  double x, y, angle;
+  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);
+    return (atan2(c.x - this.x, this.y - c.y) - PI / 2) % (2 * PI);
   }
 
   double distance(PositionComponent c) {
@@ -28,22 +33,33 @@ abstract class SpriteComponent extends PositionComponent {
   double width, height;
   Image image;
 
-  final Paint paint = new Paint()..color = new Color(0xffffffff);
+  final Paint paint = new Paint()
+    ..color = new Color(0xffffffff);
 
-  SpriteComponent.square(double size, String imagePath) : this.rectangle(size, size, imagePath);
+  SpriteComponent.square(double size, String imagePath)
+      : this.rectangle(size, size, imagePath);
 
   SpriteComponent.rectangle(this.width, this.height, String imagePath) {
-    Flame.images.load(imagePath).then((image) { this.image = image; });
+    Flame.images.load(imagePath).then((image) {
+      this.image = image;
+    });
   }
 
   render(Canvas canvas) {
     canvas.translate(x, y);
-    canvas.rotate(PI/2 + angle);
-    canvas.translate(-width/2, -height/2);
+    canvas.rotate(angle); // TODO: rotate around center
     if (image != null) {
-      Rect src = new Rect.fromLTWH(0.0, 0.0, image.width.toDouble(), image.height.toDouble());
-      Rect dst = new Rect.fromLTWH(0.0, 0.0, width, height);
-      canvas.drawImageRect(image, src, dst, paint);
+      final Rect outputRect = new Rect.fromLTWH(0.0, 0.0, width, height);
+
+      final Size imageSize = new Size(
+          image.width.toDouble(), image.height.toDouble());
+      final FittedSizes sizes = applyBoxFit(
+          BoxFit.fill, imageSize, outputRect.size);
+      final Rect inputSubrect = Alignment.center.inscribe(
+          sizes.source, Offset.zero & imageSize);
+      final Rect outputSubrect = Alignment.center.inscribe(
+          sizes.destination, outputRect);
+      canvas.drawImageRect(image, inputSubrect, outputSubrect, paint);
     }
   }