Flutter 3D网页渲染插件web3d的使用

本文将介绍如何使用Flutter中的web3d插件进行3D网页渲染。web3d是一个支持在Flutter中实现3D图形渲染的插件，可以帮助开发者轻松创建交互式3D内容。

环境准备

在开始之前，请确保您的开发环境已正确配置：

1. 安装Flutter SDK。
2. 配置好Flutter开发环境，包括Dart语言支持。
3. 使用支持的浏览器（如Chrome）来运行和测试您的应用。

插件安装

首先，在pubspec.yaml文件中添加web3d依赖：

dependencies:
  web3d: ^版本号

然后执行以下命令以更新依赖项：

flutter pub get

示例代码

以下是一个简单的示例代码，展示如何使用web3d插件进行3D渲染。

示例代码

import 'package:flutter/material.dart';
import 'package:web3d/web3d.dart';
import 'package:get/get.dart';

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  [@override](/user/override)
  Widget build(BuildContext context) {
    return GetMaterialApp(
      title: 'Flutter Web3 Example',
      home: Home(),
    );
  }
}

class HomeController extends GetxController {
  // 初始化状态变量
  bool get isConnected => Ethereum.isSupported && currentAddress.isNotEmpty;

  String currentAddress = '';

  int currentChain = -1;

  Web3Provider? web3wc;

  // 连接到钱包
  connectProvider() async {
    if (Ethereum.isSupported) {
      final accs = await ethereum!.requestAccount();
      if (accs.isNotEmpty) {
        currentAddress = accs.first;
        currentChain = await ethereum!.getChainId();
      }
      update();
    }
  }

  // 使用Web3Provider连接到钱包
  connectWC() async {
    await wc.connect();
    if (wc.connected) {
      currentAddress = wc.accounts.first;
      currentChain = 56;
      web3wc = Web3Provider.fromWalletConnect(wc);
    }
    update();
  }

  // 清除状态
  clear() {
    currentAddress = '';
    currentChain = -1;
    wcConnected = false;
    web3wc = null;
    update();
  }

  // 初始化状态
  init() {
    if (Ethereum.isSupported) {
      connectProvider();

      ethereum!.onAccountsChanged((accs) {
        clear();
      });

      ethereum!.onChainChanged((chain) {
        clear();
      });
    }
  }

  // 获取最新区块信息
  getLastestBlock() async {
    print(await provider!.getLastestBlock());
    print(await provider!.getLastestBlockWithTransaction());
  }

  // 测试RPC Provider
  testProvider() async {
    final rpcProvider = JsonRpcProvider('https://bsc-dataseed.binance.org/');
    print(rpcProvider);
    print(await rpcProvider.getNetwork());
  }

  // 测试链切换
  testSwitchChain() async {
    await ethereum!.walletSwitchChain(97, () async {
      await ethereum!.walletAddChain(
        chainId: 97,
        chainName: 'Binance Testnet',
        nativeCurrency: CurrencyParams(name: 'BNB', symbol: 'BNB', decimals: 18),
        rpcUrls: ['https://data-seed-prebsc-1-s1.binance.org:8545/'],
      );
    });
  }

  [@override](/user/override)
  void onInit() {
    init();
    super.onInit();
  }
}

class Home extends StatelessWidget {
  [@override](/user/override)
  Widget build(BuildContext context) {
    return GetBuilder<HomeController>(
      init: HomeController(),
      builder: (h) => Scaffold(
        body: Center(
          child: Column(
            children: [
              Container(height: 10),
              Builder(
                builder: (_) {
                  var shown = '';
                  if (h.isConnected && h.isInOperatingChain)
                    shown = 'You\'re connected!';
                  else if (h.isConnected && !h.isInOperatingChain)
                    shown = 'Wrong chain! Please connect to BSC. (56)';
                  else if (Ethereum.isSupported)
                    return OutlinedButton(
                        child: Text('Connect'), onPressed: h.connectProvider);
                  else
                    shown = 'Your browser is not supported!';

                  return Text(
                    shown,
                    style: TextStyle(fontWeight: FontWeight.bold, fontSize: 20),
                  );
                },
              ),
              Container(height: 30),
              if (h.isConnected && h.isInOperatingChain) ...[
                TextButton(
                    onPressed: h.getLastestBlock,
                    child: Text('Get Latest Block')),
                Container(height: 10),
                TextButton(
                    onPressed: h.testProvider,
                    child: Text('Test Binance RPC Provider')),
                Container(height: 10),
                TextButton(onPressed: h.test, child: Text('Test')),
                Container(height: 10),
                TextButton(
                    onPressed: h.testSwitchChain,
                    child: Text('Test Switch Chain')),
              ],
              Container(height: 30),
              Row(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  Text('Wallet Connect connected: ${h.wcConnected}'),
                  Container(width: 10),
                  OutlinedButton(
                      child: Text('Connect to WC'), onPressed: h.connectWC)
                ],
              ),
              Container(height: 30),
              if (h.wcConnected && h.wc.connected) ...[
                Text(h.wc.walletMeta.toString()),
              ],
            ],
          ),
        ),
      ),
    );
  }
}