@Saeed I am doing all of the data fetching, VTK filtering, and VTK rendering with C++ compiled to WebAssembly (WASM) using Emscripten. The only functionality that is done in JS is simple user interaction, such as selecting parameters for what data the user wants to see. This is passed as a string from JS to WebAssembly and in WebAssembly I am fetching the data based on the string that was passed. I then display the data using VTK C++.
So basically, the JS handles all button and menu selections only. I am not using vtk.js at all. This information is passed to WebAssembly as a simple string, and then in C++ I am fetching the data and displaying it with VTK C++.
Look up “Emscripten Fetch” to see how to “fetch” data from a server.