https://ossia.io does some of it, I've been working on a new release that also supports the whole QtQuick stack in the node graph items but you can already combine videos & shader effects. There are also text and image nodes but i want to redo them, they were quick and dirty prototypes for an exhibition and don't support some of the use cases artists using the software then came up with, e.g. sifting through gigabytes of images more or less instantly.
The underlying C++ part of this is kiiinda independent of the rest of the app, at least the graph part : https://github.com/ossia/score/tree/master/src/plugins/score... - I'm sure it wouldn't be too hard to extract this folder specifically. Shaders use the ISF specification (https://isf.video) and the backend is through Qt's RHI so things are then mapped to metal, vk, d3d or GL.
Ossia looks very cool. I have also developed a node-based tool in Qt/C++ (https://www.easydatatransform.com/). Might be interesting to talk Qt-related stuff with you some time (Qt versions, deployment, OSs etc).
The underlying C++ part of this is kiiinda independent of the rest of the app, at least the graph part : https://github.com/ossia/score/tree/master/src/plugins/score... - I'm sure it wouldn't be too hard to extract this folder specifically. Shaders use the ISF specification (https://isf.video) and the backend is through Qt's RHI so things are then mapped to metal, vk, d3d or GL.