c42a3f070a removed PAUSE_REQUESTED, which turned the acknowledge-wait in
EmuThreadPause() into dead code: emuThreadState is set to PAUSED on the line
above the `while (emuThreadState != PAUSED)` poll, so pause returns without the
emu thread parked at a frame boundary. retro_serialize / retro_unserialize then
race the GL ThreadFrame handshake and can deadlock the emu thread under periodic
save-states.
Restore the minimal handshake: EmuThreadPause() requests the pause, the emu
thread transitions PAUSE_REQUESTED -> PAUSED at its own frame boundary, and
retro_run treats the request window as paused. START_REQUESTED stays removed and
the new shutdown path is untouched.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
- Add frametests.py: walks a dump tree, renders each dump per config variant
through PPSSPPHeadless, generates reference images when missing and compares
MSE when present, and writes a self-contained HTML report. The JSON config
(which lives with the test set, not in the repo) points at the data tree
and defines variants as suffix -> CLI args, e.g. 'soft': '--graphics=software'.
- Headless: --screenshot-save saves PNG when the path ends in .png; new
--screenshot-diff always writes a visual comparison when comparing;
screenshot comparison failures (mismatch or unloadable reference) now fail
the test instead of passing silently.
- Read back framebuffers top-down, flipping only for BMP output/input
(fixes upside-down PNG references). Sync libretro copy accordingly.
- Document the system in docs/frametest.md; add AGENTS.md reference.
