De-coupled remaining aspects of game into packages

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

packages/wolf_3d_renderer/lib/weapon_painter.dart

@@ -0,0 +1,54 @@
+import 'package:flutter/material.dart';
+import 'package:wolf_3d_data_types/wolf_3d_data_types.dart';
+import 'package:wolf_3d_renderer/color_palette.dart';
+
+class WeaponPainter extends CustomPainter {
+  final Sprite? sprite;
+
+  // Initialize a reusable Paint object and disable anti-aliasing to keep the
+  // pixels perfectly sharp and chunky.
+  final Paint _paint = Paint()
+    ..isAntiAlias = false
+    ..style = PaintingStyle.fill;
+
+  WeaponPainter({required this.sprite});
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    if (sprite == null) return;
+
+    // Calculate width and height separately in case the container isn't a
+    // perfect square
+    double pixelWidth = size.width / 64;
+    double pixelHeight = size.height / 64;
+
+    for (int x = 0; x < 64; x++) {
+      for (int y = 0; y < 64; y++) {
+        int colorByte = sprite![x][y];
+
+        if (colorByte != 255) {
+          // 255 is our transparent magenta
+          _paint.color = ColorPalette.vga[colorByte];
+
+          canvas.drawRect(
+            Rect.fromLTWH(
+              x * pixelWidth,
+              y * pixelHeight,
+              // Add a tiny 0.5 overlap to completely eliminate visual seams
+              pixelWidth + 0.5,
+              pixelHeight + 0.5,
+            ),
+            _paint,
+          );
+        }
+      }
+    }
+  }
+
+  @override
+  bool shouldRepaint(covariant WeaponPainter oldDelegate) {
+    // ONLY repaint if the actual animation frame (sprite) has changed!
+    // This saves massive amounts of CPU when the player is just walking around.
+    return oldDelegate.sprite != sprite;
+  }
+}