99 lines
2.1 KiB
Dart
99 lines
2.1 KiB
Dart
import 'dart:async';
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import 'dart:typed_data';
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import 'package:flutter/cupertino.dart';
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import 'package:flutter/material.dart';
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import 'dart:ui' as ui;
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import 'package:flutter/services.dart';
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import '../components/coordinate_pro.dart';
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class Paper extends StatefulWidget {
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const Paper({super.key});
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@override
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_PaperState createState() => _PaperState();
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}
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class _PaperState extends State<Paper> {
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ui.Image? _img;
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bool get hasImage => _img != null;
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@override
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void initState() {
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super.initState();
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_loadImage();
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}
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@override
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Widget build(BuildContext context) {
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return Container(
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color: Colors.white,
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child: CustomPaint(
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painter: ImageShaderPainter(_img),
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),
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);
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}
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void _loadImage() async {
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_img = await loadImageFromAssets('assets/images/wy_200x300.jpg');
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setState(() {});
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}
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//读取 assets 中的图片
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Future<ui.Image>? loadImageFromAssets(String path) async {
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ByteData data = await rootBundle.load(path);
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return decodeImageFromList(data.buffer.asUint8List());
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}
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}
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class ImageShaderPainter extends CustomPainter {
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ui.Image? img;
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ImageShaderPainter(this.img);
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Coordinate coordinate = Coordinate();
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@override
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void paint(Canvas canvas, Size size) {
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if(img == null) return;
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coordinate.paint(canvas, size);
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canvas.translate(size.width / 2, size.height / 2);
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Paint paint = Paint()..shader = ImageShader(
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img!,
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TileMode.repeated,
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TileMode.repeated,
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Float64List.fromList([
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1, 0, 0, 0,
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0, 1, 0, 0,
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0, 0, 1, 0,
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0, 0, 0, 1,
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]));
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canvas.drawCircle(Offset(100, 100), 50, paint);
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canvas.translate(120, 0);
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canvas.drawCircle(
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Offset(100, 100),
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50,
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paint
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..strokeWidth = 10
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..style = PaintingStyle.stroke);
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canvas.translate(-120*2.0, 0);
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canvas.drawLine(
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Offset(100 , 50),
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Offset(100 , 50 + 100.0),
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paint
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..strokeWidth = 30
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..style = PaintingStyle.stroke);
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}
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@override
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bool shouldRepaint(CustomPainter oldDelegate) => true;
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}
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