The last few days have been a deep dive into V\OS’s graphics pipeline. What started as “make the DRM backend boot in QEMU” turned into building out per-window GPU compositing, fixing Haiku’s menu rendering, writing a gears demo, and learning more about virtio-gpu’s limitations than I ever wanted to know.

where we started

V\OS had a DRM display backend from x512’s Haiku work. It could put pixels on screen via dumb buffers and page flips. But there was no cursor, windows flickered when dragged, the GBM/EGL code had never been tested on a running system, and the whole thing only worked with -vga std in QEMU.