vk_hook.cpp and coop_vk_layer.cpp each carried a verbatim copy of the
swap-chain registry -- the SwapInfo struct, the vector+mutex, find_swap,
the create-time de-dup + LRU cap, and the present-time lookup -- because
they are two independent early-presence paths (inline hook vs implicit
layer). The tracking logic is identical, so lift it into one
VkSwapchainRegistry (hook/src/vk_swapchain_registry.hpp); each module
owns an instance. add() de-dups + LRU-caps, lookup() copies the frame
out under the lock, clear() resets -- same behavior, one definition.
Net -45 lines. mock_game_test exercises both paths (the inline-hook vk
storm and the implicit-layer capture) and passes.
hook_registry.cpp still used strncpy for the hook-name copy (the same
class the log-ring fix addressed) -- replace with a bounded memcpy.
coop_vk_layer.cpp's debug logger used _wfopen -- switch to _wfopen_s.
Both were the only remaining C4996s in our own code.
Run clang-format (the repo's .clang-format: LLVM base, 120 cols, tabs,
Allman functions) over every source file so the tree is formatter-clean.
Whitespace only -- no behavior change; full x64 + x86 suites pass.
Also set SortIncludes: false in .clang-format. Windows include order is
load-bearing (windows.h must precede tlhelp32.h / mmreg.h / xinput.h /
dinput.h; winsock2.h must precede windows.h), and the default
alphabetical sort reorders tlhelp32.h ahead of windows.h -- a build
break. Leaving order alone keeps the manual, correct grouping.
Consolidate four copies of the keyed-mutex shared-texture setup
(present/opengl/d3d9/vk_capture) into one RAII SharedVideoTexture,
two copies of find_main_window into find_window.hpp, audio_hook's
hand-rolled detour guard into the shared DetourGate, the duplicated
vtable_method into vtable_hook.hpp, and the near-identical
Present/Present1 and SwapBuffers/wglSwapBuffers detour pairs into one
shared body each. The vk_layer and vk_capture_perf_test targets now
compile debug_log.cpp since the shared texture code logs.
Comments no longer narrate the past: drop stress-test/game anecdotes,
"used to"/"the old model" phrasing, plan-step labels, and pointers to
docs that do not exist; fix present_hook.hpp/opengl_hook.hpp claims
that predate the D3D12/D3D9/Vulkan backends. Net -266 lines, no
behavior change (full x64 + x86 suites pass, including the mock-game
hook/unhook storm).
g_swaps (vk_hook.cpp and the Vulkan layer) is pushed from the create-swapchain
detour and iterated by the present detour, which can run on different game
threads (Vulkan external sync is per-object, not global), and cleared on removal
from another thread -- all with no mutex. A push_back realloc could dangle the
SwapInfo* a concurrent find_swap/present is using. It was also never pruned, so a
game that recreates its swapchain each resize grew it without bound and could
match a recycled handle's stale images.
Add g_swaps_mutex around every access; the present detour now copies the matched
swapchain's fields out under the lock and captures without holding it (no GPU
submit under the lock, no dangling pointer). Create de-dups by handle and an LRU
cap (8) bounds growth -- the active swapchain is the newest, so it's never
evicted. Deliberately NOT hooking vkDestroySwapchainKHR: forwarding a destroy
incorrectly could break the game, and the de-dup + cap already bound growth and
defeat handle recycling.
Verified real by inspection (a concurrent-create+present Vulkan race isn't
deterministically reproducible in a test); validated by the full mock_game_test
Vulkan paths (capture + layer + too-late) staying green.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
The capture must never change vsync, and must not frame-limit itself.
- Removed the ~150 Hz capture throttle from VkCapture. It was wrong: vsync already
paces capture (a 144 Hz FIFO game presents 144x/s, so we mirror 144x/s). The only
limiter left is ring backpressure (skip a frame if the reaper is behind), which is
correctness, not a cap, and never touches the game's present thread or sync mode.
- The layer/hook already pass VkSwapchainCreateInfoKHR straight through, so the
present mode (= the sync mode) is untouched. Added a presentMode log to prove it.
Measured on Sphere Spectacle (direct launch, layer attached): presentMode=2 (FIFO),
steady 144.0 fps, and with the throttle gone the mirror now tracks it at 144/s
(was capped ~130). The earlier 400-600 fps reading was a direct-launch artifact --
a non-foreground windowed FIFO app isn't throttled by DWM -- not the layer, and not
the case through Steam (144). vk_validate now states the mirror follows the present
rate (no throttle) and still asserts a present-rate floor.
Full suite 21/21.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Against Sphere Spectacle (144 FPS, runs without Steam) the implicit-layer
capture dropped the game to ~3 FPS. Measured cause (per-stage trace in the
layer): the read-back ran on the game's PRESENT THREAD and spent ~370 ms per
1080p frame -- not the GPU copy (~2 ms) but the CPU swizzle, because the staging
buffer was a plain HOST_VISIBLE|HOST_COHERENT type (write-combined / uncached on
a discrete GPU), where a scattered CPU read runs at PCIe latency. 3 captures/s =
the 3 FPS the user saw.
Test-first: tests/vk_capture_perf_test reproduces the stall as a deterministic
unit test (372 ms/present, ratio 1.0 -> FAIL via `--sync`), then proves the fix
(0.02 ms/present, byte-correct BGRA->RGBA, ratio ~0 -> PASS).
Fix: extract the near-identical read-back from vk_hook.cpp and coop_vk_layer.cpp
into one shared coop::hook::VkCapture that:
* has the present thread only record + submit the copy (sub-ms) and return;
* runs a dedicated reaper thread for the fence wait + swizzle + D3D upload, off
the critical path, with a ring of in-flight slots (game never waits);
* allocates HOST_CACHED staging (fast CPU read), invalidating when non-coherent;
* throttles capture to ~150 Hz (a guest stream is <= the host refresh; no point
mirroring an uncapped 400+ FPS game and burning reaper CPU).
Real-game A/B: present rate now matches the no-capture baseline (605->470 vs
593->405 over the same ramp) with the mirror at ~130 fps -- no measurable impact.
Also adds present-thread overhead guards to the other GPU backends' hook tests
(present_overhead.hpp): DX11 0.05 ms, DX12 0.34 ms, OpenGL 0.09 ms overhead, all
asserted < one 60 Hz frame, so any future synchronous-stall regression fails.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
A real chain-aware Vulkan implicit layer the loader inserts at vkCreateInstance
-- the reliable early-presence path for games that init Vulkan immediately,
which the inline-hook vk_hook can't catch. It intercepts vkCreateInstance /
Device / CreateSwapchainKHR / QueuePresentKHR via proper layer-chain dispatch
and does the same read-back capture (vkCmdCopyImageToBuffer -> swizzle ->
hook-owned D3D11 shared texture, with present-semaphore re-chaining) as vk_hook.
The loader/layer link structs (VkLayer*CreateInfo, VkNegotiateLayerInterface)
aren't in Vulkan-Headers, so they're hand-declared to interface version 2. Key
gotcha found via tracing: the loader tags those link structs with small internal
sType values (LOADER_INSTANCE_CREATE_INFO=47, _DEVICE=48), not the 1000000000
range -- matching the wrong value made the device-chain walk fail.
Scoping: an implicit layer loads into every Vulkan app, so it only *captures*
when COOP_VK_LAYER_FORCE is set (tests) or this process's image matches
%TEMP%\coop_vk_target.txt (the host writes it); otherwise pure pass-through.
mock_game_test registers it via VK_LAYER_PATH/VK_INSTANCE_LAYERS and decodes
frames through it. Ships at the bin root with its JSON manifest.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
