gitadora: (arena model) simulate Realtek device, fix asio redirect hooks (#732)

## Link to GitHub Issue or related Pull Request, if one exists #730, #718 ## Description of change Part 1) When ASIO is in use, the game also looks for a Realtek device so that it can open a WASAPI Exclusive mode stream for headphones. Add an option to fake that, in case the user doesn't have a Realtek device. Part 2) `-gdaasio` wasn't workign properly - fix the logic. ## Testing Seems to work with FlexASIO, and Xonar with no real Realtek device.
2026-06-05 00:08:52 -07:00
parent 85058c2156
commit 2dae86a6f2
15 changed files with 504 additions and 8 deletions
@@ -0,0 +1,54 @@
+#pragma once
+
+#include <atomic>
+#include <optional>
+#include <thread>
+#include <vector>
+
+#include <audioclient.h>
+
+#include "hooks/audio/implementations/backend.h"
+
+// discards all audio while pacing the game's event handle once per buffer period, so the game
+// keeps running normally with nothing output to any real device. routed through the shared
+// DummyIAudioClient, the same plumbing the asio backend uses.
+struct NullDiscardBackend final : AudioBackend {
+    ~NullDiscardBackend() final;
+
+    const WAVEFORMATEXTENSIBLE &format() const noexcept override;
+
+    HRESULT on_initialize(
+        AUDCLNT_SHAREMODE *,
+        DWORD *,
+        REFERENCE_TIME *hnsBufferDuration,
+        REFERENCE_TIME *,
+        const WAVEFORMATEX *pFormat,
+        LPCGUID) override;
+    HRESULT on_get_buffer_size(uint32_t *buffer_frames) override;
+    HRESULT on_get_stream_latency(REFERENCE_TIME *latency) override;
+    HRESULT on_get_current_padding(std::optional<uint32_t> &padding_frames) override;
+    HRESULT on_is_format_supported(
+        AUDCLNT_SHAREMODE *,
+        const WAVEFORMATEX *,
+        WAVEFORMATEX **ppClosestMatch) override;
+    HRESULT on_get_mix_format(WAVEFORMATEX **) override;
+    HRESULT on_get_device_period(
+        REFERENCE_TIME *default_device_period,
+        REFERENCE_TIME *minimum_device_period) override;
+    HRESULT on_start() override;
+    HRESULT on_stop() override;
+    HRESULT on_set_event_handle(HANDLE *event_handle) override;
+    HRESULT on_get_buffer(uint32_t num_frames_requested, BYTE **ppData) override;
+    HRESULT on_release_buffer(uint32_t, DWORD) override;
+
+private:
+    void pace_loop();
+
+    WAVEFORMATEXTENSIBLE format_ {};
+    uint32_t buffer_frames = 0;
+    REFERENCE_TIME period_reftime = 0;
+    HANDLE relay_handle = nullptr;
+    std::vector<BYTE> scratch;
+    std::thread pacing_thread;
+    std::atomic<bool> running = false;
+};