Accelerating 2D - 3D Graphics in Qt 6
This overview tutorial is from the Qt Virtual tech Conference in 2020. It provides a good overview of what is going on under the hood in Qt 6, and how that was changed from what was going on in Qt 5.14 and 5.15.
Here's a followup from fall 2020 to help out understanding how all of this comes together in Qt 6.
Redirecting Qt Quick rendering
CMake in build system converts .frag files to .qsb files for inclusion in the application