vtk.js给图形上色

我们可以通过vtkColorTransferFunction设置不同灰度值进行着色

import vtkColorTransferFunction from 'vtk.js/Sources/Rendering/Core/ColorTransferFunction';

const ctfun = vtkColorTransferFunction.newInstance();

ctfun.addRGBPoint(0, 1.0, 0, 0);//立方体的颜色，红色

通过vtkPiecewiseFunction的立体分段设置透明度

const actor = vtkVolume.newInstance();//可视化实体

const ofun = vtkPiecewiseFunction.newInstance();

actor.getProperty().setScalarOpacity(0, ofun);

映射筛选数据源

const reader = vtkHttpDataSetReader.newInstance({
    fetchGzip: true,
});

reader
    .setUrl(`/data/LIDC2.vti`, { loadData: true })
    .then(() => {
        const data = reader.getOutputData();
        actor.setInputData(data);
        actor.setMapper(imageMapperI);
        renderer.addActor(imageMapperI);
        renderer.resetCamera();
        renderWindow.render();
})

利用这个过程，我们最终给截面上色，结果图如下：