DataArray example

Web
8

In vtk.js you can not create an empty vtkDataArray unless you state it explicitly.

const emptyArray = vtkDataArray.newInstance({ empty: true });
const values = new Float32Array(size * 3);
emptyArray.setData(values, 3);
emptyArray.setName('velocity')

or better

const values = new Float32Array(size * 3);
const filledArray = vtkDataArray.newInstance({ name: 'velocity', values, numberOfComponents: 3 });

polydata.getPointData().addArray(filledArray); // AddArray is for the C++ not the JS