books

2023-12-21 22:06:28 +08:00
parent 8b846f86d3
commit 2f4e8d3564
62 changed files with 6651 additions and 92 deletions
--- a/packages/idraw/lib/p15/s03.dart
+++ b/packages/idraw/lib/p15/s03.dart
@@ -0,0 +1,96 @@
+
+import 'package:flutter/material.dart';
+
+import '../components/coordinate_pro.dart';
+
+class Paper extends StatefulWidget {
+  const Paper({super.key});
+
+  @override
+  _PaperState createState() => _PaperState();
+}
+
+class _PaperState extends State<Paper> with SingleTickerProviderStateMixin {
+  late AnimationController _controller;
+
+  @override
+  void initState() {
+    super.initState();
+    _controller = AnimationController(
+      duration: const Duration(milliseconds: 500),
+      vsync: this,
+    )..repeat();
+  }
+
+  @override
+  void dispose() {
+    _controller.dispose();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    return Container(
+      color: Colors.white,
+      child: CustomPaint(
+        painter: PaperPainter(_controller),
+      ),
+    );
+  }
+}
+
+class PaperPainter extends CustomPainter {
+  final Coordinate coordinate = Coordinate();
+  Paint _helpPaint = Paint();
+
+  final Animation<double> repaint;
+
+  PaperPainter(this.repaint) : super(repaint: repaint);
+
+  double waveWidth = 80;
+  double wrapHeight = 100;
+  double waveHeight = 20;
+
+  @override
+  void paint(Canvas canvas, Size size) {
+    coordinate.paint(canvas, size);
+    canvas.translate(size.width / 2, size.height / 2);
+
+    Path path = Path();
+    Paint paint = Paint()
+      ..color = Colors.orange
+      ..style = PaintingStyle.stroke
+      ..strokeWidth = 2;
+
+    canvas.save();
+    // canvas.translate(-2*waveWidth, 0);
+    canvas.translate(-2 * waveWidth + 2 * waveWidth * repaint.value, 0);
+    path.moveTo(0, 0);
+    path.relativeQuadraticBezierTo(
+        waveWidth / 2, -waveHeight * 2, waveWidth, 0);
+    path.relativeQuadraticBezierTo(waveWidth / 2, waveHeight * 2, waveWidth, 0);
+    path.relativeQuadraticBezierTo(
+        waveWidth / 2, -waveHeight * 2, waveWidth, 0);
+    path.relativeQuadraticBezierTo(waveWidth / 2, waveHeight * 2, waveWidth, 0);
+    path.relativeLineTo(0, wrapHeight);
+    path.relativeLineTo(-waveWidth * 2 * 2.0, 0);
+    path.close();
+    canvas.drawPath(path, paint..style = PaintingStyle.fill);
+    canvas.restore();
+
+    _drawHelp(canvas);
+  }
+
+  void _drawHelp(Canvas canvas) {
+    _helpPaint
+      ..color = Colors.purple
+      ..style = PaintingStyle.stroke
+      ..strokeCap = StrokeCap.round;
+    canvas.drawRect(Rect.fromPoints(Offset(0, -100), Offset(160, 100)),
+        _helpPaint..strokeWidth = 2);
+  }
+
+  @override
+  bool shouldRepaint(PaperPainter oldDelegate) =>
+      oldDelegate.repaint != repaint;
+}