refactor: ExposureSliderPainter を別ファイルに切り出し

camera_screen.dart の末尾にあった _ExposureSliderPainter (60行) を
lib/screens/camera_exposure_painter.dart に分離。
動作変更なし。718行 → 659行。

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

lib/screens/camera_exposure_painter.dart

@@ -0,0 +1,70 @@
+import 'package:flutter/material.dart';
+
+/// カメラ画面右端の露出スライダーを描画する CustomPainter。
+///
+/// - 縦トラック（白半透明）
+/// - 中央基準線（0 EV を示すマーカー）
+/// - 現在値を示すノブ（影付き白丸）
+class ExposureSliderPainter extends CustomPainter {
+  final double currentValue;
+  final double minValue;
+  final double maxValue;
+
+  const ExposureSliderPainter({
+    required this.currentValue,
+    required this.minValue,
+    required this.maxValue,
+  });
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    final trackPaint = Paint()
+      ..color = Colors.white.withValues(alpha: 0.3)
+      ..strokeWidth = 4
+      ..strokeCap = StrokeCap.round;
+
+    final centerLinePaint = Paint()
+      ..color = Colors.white54
+      ..strokeWidth = 2;
+
+    final knobPaint = Paint()
+      ..color = Colors.white
+      ..style = PaintingStyle.fill;
+
+    final knobShadowPaint = Paint()
+      ..color = Colors.black26
+      ..maskFilter = const MaskFilter.blur(BlurStyle.normal, 4);
+
+    // 縦トラック（中央線）
+    final trackX = size.width / 2;
+    canvas.drawLine(
+      Offset(trackX, 10),
+      Offset(trackX, size.height - 10),
+      trackPaint,
+    );
+
+    // 0 EV マーカー
+    canvas.drawLine(
+      Offset(trackX - 6, size.height / 2),
+      Offset(trackX + 6, size.height / 2),
+      centerLinePaint,
+    );
+
+    // ノブ位置を算出
+    final range = maxValue - minValue;
+    if (range > 0) {
+      // minValue(下端) → 0.0、maxValue(上端) → 1.0 に正規化してY座標に変換
+      final normalized = (currentValue - minValue) / range;
+      final knobY = (size.height - 20) * (1.0 - normalized) + 10;
+      canvas.drawCircle(Offset(trackX, knobY), 7, knobShadowPaint);
+      canvas.drawCircle(Offset(trackX, knobY), 6, knobPaint);
+    }
+  }
+
+  @override
+  bool shouldRepaint(ExposureSliderPainter oldDelegate) {
+    return oldDelegate.currentValue != currentValue ||
+        oldDelegate.minValue != minValue ||
+        oldDelegate.maxValue != maxValue;
+  }
+}

lib/screens/camera_screen.dart

@@ -13,6 +13,7 @@ import 'package:image_picker/image_picker.dart'; // Gallery & Camera
 import '../services/image_compression_service.dart';
 import '../theme/app_colors.dart';
 import 'camera_analysis_mixin.dart';
+import 'camera_exposure_painter.dart';
 
 
 enum CameraMode {
@@ -475,8 +476,8 @@ class _CameraScreenState extends ConsumerState<CameraScreen> with SingleTickerPr
                             height: 180,
                             width: 48, // Wider for easier tapping
                             child: CustomPaint(
-                              key: ValueKey(_currentExposureOffset), // Force repaint on value change
+                              key: ValueKey(_currentExposureOffset),
-                              painter: _ExposureSliderPainter(
+                              painter: ExposureSliderPainter(
                                 currentValue: _currentExposureOffset,
                                 minValue: _minExposure,
                                 maxValue: _maxExposure,
@@ -656,63 +657,3 @@ class _CameraScreenState extends ConsumerState<CameraScreen> with SingleTickerPr
 
 }
 
-// Custom Painter for Exposure Slider
-class _ExposureSliderPainter extends CustomPainter {
-  final double currentValue;
-  final double minValue;
-  final double maxValue;
-
-  _ExposureSliderPainter({
-    required this.currentValue,
-    required this.minValue,
-    required this.maxValue,
-  });
-
-  @override
-  void paint(Canvas canvas, Size size) {
-    final trackPaint = Paint()
-      ..color = Colors.white.withValues(alpha: 0.3)
-      ..strokeWidth = 4
-      ..strokeCap = StrokeCap.round;
-
-    final centerLinePaint = Paint()
-      ..color = Colors.white54
-      ..strokeWidth = 2;
-
-    final knobPaint = Paint()
-      ..color = Colors.white
-      ..style = PaintingStyle.fill;    final knobShadowPaint = Paint()
-      ..color = Colors.black26
-      ..maskFilter = const MaskFilter.blur(BlurStyle.normal, 4);    // Draw vertical track (centered)
-    final trackX = size.width / 2;
-    canvas.drawLine(
-      Offset(trackX, 10),
-      Offset(trackX, size.height - 10),
-      trackPaint,
-    );    // Draw center marker
-    canvas.drawLine(
-      Offset(trackX - 6, size.height / 2),
-      Offset(trackX + 6, size.height / 2),
-      centerLinePaint,
-    );    // Calculate knob position
-    final range = maxValue - minValue;
-    if (range > 0) {
-      // Normalize currentValue to 0.0-1.0 range
-      // minValue (e.g., -4.0) -> 0.0 (bottom)
-      // 0.0 (center) -> 0.5 (middle)
-      // maxValue (e.g., +4.0) -> 1.0 (top)
-      final normalized = (currentValue - minValue) / range;
-      // Map to Y coordinate: 0.0 (normalized) -> bottom, 1.0 (normalized) -> top
-      final knobY = (size.height - 20) * (1.0 - normalized) + 10;
-      // Draw knob shadow
-      canvas.drawCircle(Offset(trackX, knobY), 7, knobShadowPaint);
-      // Draw knob
-      canvas.drawCircle(Offset(trackX, knobY), 6, knobPaint);
-    }
-  }  @override
-  bool shouldRepaint(_ExposureSliderPainter oldDelegate) {
-    return oldDelegate.currentValue != currentValue ||
-        oldDelegate.minValue != minValue ||
-        oldDelegate.maxValue != maxValue;
-  }
-}

pubspec.yaml

@@ -16,7 +16,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
 # In Windows, build-name is used as the major, minor, and patch parts
 # of the product and file versions while build-number is used as the build suffix.
-version: 1.0.41+48
+version: 1.0.42+49
 
 environment:
   sdk: ^3.10.1