VTK.js学习分享

按流程先吐槽

刚刚进公司就扔过来一个项目，就好比：吃着火锅,唱着歌,突然就被麻匪劫了！

接下来甩正文。开始～～

1.什么是VTK？

可视化工具包（VTK）是一个开源，免费的软件系统，用于3D计算机图形，图像处理和可视化。它的实现包含一个ES6 JavaScript类库，该库可以集成到任何Web应用程序中。该工具包利用WebGL，并支持各种可视化算法，包括标量，矢量，张量，纹理和体积方法。VTK是Kitware商业支持的开源软件开发平台集合的一部分。简单来说，VTK.js 就是用于web上的可视化渲染库。

官网地址：kitware.github.io/vtk-js/

2.通过npm安装使用VTK（此步骤的下列容纯官网整理）

$ mkdir myVtkProject
$ cd myVtkProject
$ npm init   // init package.json 文件
$ npm install vtk.js --save
$ npm install kw-web-suite --save-dev

webpack config

// ./webpack.config.js
var path = require('path');
var webpack = require('webpack');
var vtkRules = require('vtk.js/Utilities/config/dependency.js').webpack.core.rules;

// Optional if you want to load *.css and *.module.css files
// var cssRules = require('vtk.js/Utilities/config/dependency.js').webpack.css.rules;

var entry = path.join(__dirname, './src/index.js');
const sourcePath = path.join(__dirname, './src');
const outputPath = path.join(__dirname, './dist');

module.exports = {
  entry,
  output: {
    path: outputPath,
    filename: 'MyWebApp.js',
  },
  module: {
    rules: [
        { test: /\.html$/, loader: 'html-loader' },
    ].concat(vtkRules),
  },
  resolve: {
    modules: [
      path.resolve(__dirname, 'node_modules'),
      sourcePath,
    ],
  },
};

package.json

// ./package.json
{
  [...],
  "scripts": {
    "build": "webpack --progress --colors --mode development",
    "build:release": "webpack --progress --colors --mode production",
    "start": "webpack-dev-server --content-base ./dist",

    "commit": "git cz",
    "semantic-release": "semantic-release"
  }
}

举个例子，虽然我特么根本看不懂啥玩意

// ./src/index.js
import vtkFullScreenRenderWindow from 'vtk.js/Sources/Rendering/Misc/FullScreenRenderWindow';

import vtkActor           from 'vtk.js/Sources/Rendering/Core/Actor';
import vtkCalculator      from 'vtk.js/Sources/Filters/General/Calculator';
import vtkConeSource      from 'vtk.js/Sources/Filters/Sources/ConeSource';
import vtkMapper          from 'vtk.js/Sources/Rendering/Core/Mapper';
import { AttributeTypes } from 'vtk.js/Sources/Common/DataModel/DataSetAttributes/Constants';
import { FieldDataTypes } from 'vtk.js/Sources/Common/DataModel/DataSet/Constants';

import controlPanel from './controller.html';

// ----------------------------------------------------------------------------
// Standard rendering code setup
// ----------------------------------------------------------------------------

const fullScreenRenderer = vtkFullScreenRenderWindow.newInstance();
const renderer = fullScreenRenderer.getRenderer();
const renderWindow = fullScreenRenderer.getRenderWindow();

// ----------------------------------------------------------------------------
// Example code
// ----------------------------------------------------------------------------

const coneSource = vtkConeSource.newInstance({ height: 1.0 });
const filter = vtkCalculator.newInstance();

filter.setInputConnection(coneSource.getOutputPort());
filter.setFormula({
  getArrays: inputDataSets => ({
    input: [],
    output: [
      { location: FieldDataTypes.CELL, name: 'Random', dataType: 'Float32Array', attribute: AttributeTypes.SCALARS },
    ],
  }),
  evaluate: (arraysIn, arraysOut) => {
    const [scalars] = arraysOut.map(d => d.getData());
    for (let i = 0; i < scalars.length; i++) {
      scalars[i] = Math.random();
    }
  },
});

const mapper = vtkMapper.newInstance();
mapper.setInputConnection(filter.getOutputPort());

const actor = vtkActor.newInstance();
actor.setMapper(mapper);

renderer.addActor(actor);
renderer.resetCamera();
renderWindow.render();

// -----------------------------------------------------------
// UI control handling
// -----------------------------------------------------------

fullScreenRenderer.addController(controlPanel);
const representationSelector = document.querySelector('.representations');
const resolutionChange = document.querySelector('.resolution');

representationSelector.addEventListener('change', (e) => {
  const newRepValue = Number(e.target.value);
  actor.getProperty().setRepresentation(newRepValue);
  renderWindow.render();
});

resolutionChange.addEventListener('input', (e) => {
  const resolution = Number(e.target.value);
  coneSource.setResolution(resolution);
  renderWindow.render();
});

The control template

// ./src/controller.html
<table>
  <tr>
    <td>
      <select class='representations' style="width: 100%">
        <option value='0'>Points</option>
        <option value='1'>Wireframe</option>
        <option value='2' selected>Surface</option>
      </select>
    </td>
  </tr>
  <tr>
    <td>
      <input class='resolution' type='range' min='4' max='80' value='6' />
    </td>
  </tr>
</table>

// ./dist/index.html
<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-type" content="text/html; charset=utf-8"/>
    <meta name="viewport" content="width=device-width, initial-scale=1">
  </head>
  <body>
    <script type="text/javascript" src="MyWebApp.js"></script>
  </body>
</html>

打包build项目

$ npm run build

启动服务

$ npm start

启动后效果：