> It takes a lot of work to make a usable UI out of triangles, so most applications did not go this path. One big exception was games, which were already heavy

> It takes a lot of work to make a usable UI out of triangles, so most applications did not go this path. One big exception was games, which were already heavy GPU users In the past, Scaleform was close to ubiquitous, at least for large games. Scaleform is Flash-based, so it was a vector graphics engine with a JavaScript-like language. It was presumably faster and less bloated than a browser engine would be, as a game middleware from the Xbox 360 era. But from a developer experience point of view, it closer to a browser engine than to "[making] a usable UI out of triangles." Scaleform is still pretty popular, but it has become popular to create game UIs with web technologies. You can find libCEF.dll in pretty much every game nowadays. Sometimes it's just used to render the update news or in-game store, but often the entire UI is HTML.