The animated pattern math (background sweep, moving 24px bar, frame-
counter block) was copy-pasted across all five clear-based backends
(dx9/dx10/dx11/dx12/gl). The backends MUST render an identical image --
the capture test decodes the same frame-counter block from each -- so a
drift between copies would be a silent test hazard.
Factor it into one frame_pattern() helper (plus kBarWidth) in
render_backend.hpp; each backend now consumes the computed bg/bar_x/code
values with its own API's clear/fill. mock_game_test still decodes every
backend correctly.
The mock backends presented with vsync ("a game-like cadence") -- wrong for a
perf/stress fixture: it does trivial work on an RTX 4090, so it must run as fast
as it can. Vsync capped them to tens of fps (dx9 30, dx10 23, dx11 63, dx12 126),
which hid both capture-induced slowdowns and the hook-removal race. Uncapped now:
dx9/dx10 INTERVAL_IMMEDIATE / Present(0,0) (BLT), dx11/dx12 ALLOW_TEARING +
Present(0, ALLOW_TEARING) (flip), gl wglSwapIntervalEXT(0), vk IMMEDIATE/MAILBOX.
Measured no-hook: dx9 ~21000, dx10 ~2800, dx11 ~17000, dx12 ~12000, gl ~26000, vk
~24000 fps.
mock_game_test now adds a present-rate floor per backend (>= 300/s while
capturing): with the hook live every backend stays in the hundreds-thousands
(vk 13500, dx11 9000+, gl 1800, dx9/10 ~1000-1600, dx12 2500). This is the
dimension the frame-advance checks missed -- the Vulkan 144->3 FPS stall still
advanced frames -- so it catches a present-thread stall OR an accidental vsync.
The faster storm exposed the hook-removal UAF fixed in the previous commit.
README roadmap + lessons-learned updated (incl. correcting the old "reset makes
in-flight trampoline calls safe" claim). Full suite 21/21.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A tiny test "game" for exercising the capture/audio/hook paths. Opens a normal
window and renders an animated pattern -- moving bar + per-frame background so
motion (and dropped frames) are obvious -- with a top-left block whose RGB
encodes the exact frame number, so a capture test can decode it and detect
dropped / duplicated / stale frames. Selectable backend (dx11 / dx12 today),
behind a RenderBackend interface so OpenGL/Vulkan can be added. With audio args
it also plays a configurable WASAPI tone (shared ToneSource), so it's a full A/V
source with a window (unlike coop_tone).
coop_mock_game.exe [dx11|dx12] [seconds] [rate] [channels] [bits] [pcm|float]
Milestone 1 of the mock-game roadmap item (the stress-test suite follows).
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
