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Learning vtkjs之ImageMarchingSquares

news 2025/7/2 7:47:04

体积等值线处理

介绍

vtkImageMarchingSquares - 对图像（或来自体积的切片）进行等值线处理

给定一个指定的等值，使用Marching Squares算法（3D Marching Cubes算法的2D版本）生成等值线。

效果

在这里插入图片描述
自己增加了两个小球，主要是对比一下ISO前后的效果

核心代码

参数更新

const updateParam = (value) => {const { mSquares, renderWindow } = context.current;mSquares.setSlicingMode(value);setState({...state,slicingMode: value,});renderWindow.render();};

主要流程

const fullScreenRenderer = vtkFullScreenRenderWindow.newInstance({background: [0, 0, 0],rootContainer: vtkContainerRef.current,});const renderer = fullScreenRenderer.getRenderer();const renderWindow = fullScreenRenderer.getRenderWindow();const { Operation } = vtkImplicitBoolean;const actor = vtkActor.newInstance();renderer.addActor(actor);const mapper = vtkMapper.newInstance();actor.setMapper(mapper);// Build pipelineconst sphere = vtkSphere.newInstance({center: [-2.5, 0.0, 0.0],radius: 3.0,});const sphere2 = vtkSphere.newInstance({center: [2.5, 0.0, 0.0],radius: 0.5,});// const plane = vtkPlane.newInstance({ origin: [0, 0, 0], normal: [0, 1, 0] });const impBool = vtkImplicitBoolean.newInstance({operation: Operation.UNION,functions: [sphere, sphere2],});const sample = vtkSampleFunction.newInstance({implicitFunction: impBool,sampleDimensions: [50, 50, 50],modelBounds: [-5.0, 5.0, -2.0, 2.0, -1.0, 1.0],});// Isocontourconst mSquares = vtkImageMarchingSquares.newInstance({ slice: 1 });mSquares.setSlicingMode(2);// Connect the pipeline propermSquares.setInputConnection(sample.getOutputPort());mapper.setInputConnection(mSquares.getOutputPort());// Update the pipeline to obtain metadata (range) about scalarssample.update();const cValues = [];const [min, max] = sample.getOutputData().getPointData().getScalars().getRange();const step = 20;for (let i = 0; i < step; ++i) {cValues[i] = min + (i / (step - 1)) * (max - min);}mSquares.setContourValues(cValues);mSquares.setSlice(25);// Create an outline// Bounding boxconst outline = vtkOutlineFilter.newInstance();outline.setInputConnection(sample.getOutputPort());const outlineMapper = vtkMapper.newInstance();outlineMapper.setInputConnection(outline.getOutputPort());const outlineActor = vtkActor.newInstance();outlineActor.setMapper(outlineMapper);renderer.addActor(outlineActor);context.current = {mSquares,renderer,renderWindow,};// 同步sphereconst sphereReference = createSphere([-2.5, 0.0, 0.0], 3.0);renderer.addActor(sphereReference);const sphereReference2 = createSphere([2.5, 0.0, 0.0], 0.5);renderer.addActor(sphereReference2);renderer.resetCamera();renderWindow.render();