Earlier quoted context omitted.
I'm open to the possibility that I'm that wrong in my understanding, but this didn't help me understand any better at all. The technique does sound similar to me. Both (as I understand it) maintain a representation in memory of the final rendering and use a diff to determine which parts of the rendering to perform. The "virtual DOM" technique isn't strictly tied to a browser DOM, though the term is a reference to tha…
virtual DOM implies DOM existence. DOM based systems use so called retained mode rendering. But this one uses something that can be classified as immediate mode rendering. Check https://docs.microsoft.com/en-us/windows/win32/learnwin32/re...
A virtual DOM, to me, means that the application renders by, every time, constructing data structures which are handed off to be reconciled with the display.
If, as in an HTML application, you render by means of a retained mode real DOM, then the reconciliation is via comparison of the virtual with the real. But that's not the only way to handle the output of the construction of a virtual DOM; it could figure out how those structures intersect with the dirty rectangle/s, and only render the subtree of the DOM which applies.
rxi's technique resembles a virtual DOM of depth 2 (1 root and everything is a child) and absolute positioning, though it's even closer to an OpenGL display list or combined vertex & command buffer. For that reason, I think it's a little bit of a stretch; not on the virtual DOM angle, but on the not particularly DOM-like nature of the drawing commands.