I don't know Datashader that well, but from what I understand, it generates an image from a set of primitives (e.g. points), and then allows you to interactively inspect that image. It does not re-render the points on every frame like Fastplotlib/Pygfx does.
All true, except the bit that wgpu-py compiles to WASM. It's all desktop.
In the plans that we do have for running the browser, Fastplotlib, Pygfx and wgpy-py will still be Python, running on CPython that is compiled to WASM (via Pyodide). But instead of wgpu-py cffi-ing into a C library, it would make JS calls to the WebGPU API.
To clarify this a bit, wgpu is a Rust implementation of WebGPU, just like Dawn is a C++ implementation of WebGPU (by Google). Both projects expose a C-api following webgpu.h. wgpu-py Should eventually be able to work with both. (Disclaimer: I'm the author of wgpu-py)
Not sure if this is what you're asking :) but the UI framework will somehow provide access to the OS-level surface object, so that the GPU API can render directly to the screen.
Yeah, sounds like QRhi is about at the level of WebGPU/wgpu-py.
It sounds to me that Qt created their own abstraction over Vulkan and co, because wgpu did not exist yet.
I can't really compare them from a technical pov, because I'd have to read more into QRhi. But QRhi is obviously tight to / geared towards Qt, which has advantages, as well as disadvantages.
Wgpu is more geared towards the web, so it likely has more attention to e.g. safety. WebGPU is also based on a specification, there is a spec for the JS API as well as a spec for webgpu.h. There's actually two implementations (that I know of) that implement webgpu.h: wgpu-native (which runs WebGPU in firefox) and Dawn (which runs WebGPU in Chrome).
Apart from being based on wgpu, Pygfx also has a better design IMO. Korijn deserves the credit for this. It's inspired by ThreeJS, based on the idea to keep things modular.
We deliberately don't try to create an API that allows you to write visualizations with as few lines as possible. We focus on a flexible generic API instead, even if it's sometimes a bit verbose.
I wish. The revenue from the ads goes to readthedocs, AFAIK nothing is paid to the maintainers of the project.
That said, readthedocs is a pretty nice platform to host your docs in a simple way. Plus users are not tracked. So personally I don't mind so much, but I'm going to have a look at the paid plan to remove ads for our users :)
This is indeed one of the major differences. Many of the problems that are plaguing Vispy are related to OpenGL. The use of wgpu solves many of them.
Also, wgpu forces you to prepare visualizations in pipeline objects, which at drawtime require just a few calls. In OpenGL there is way more work for each object being visualized at drawtime. This overhead is particularly bad on Python. So this particular advantage of wgpu is extra advantageous for Python.
It's definitely still our intention to make it run in the browser. We're not actively working on that yet, but we've recently been able to remove some hurdles on that path, in particular the issue related to Webgpu being async.
Depending on your GPU, you can render say 1-50 million points smoothly. Also see e.g. https://github.com/pygfx/pygfx/discussions/819