Shader ownership change

CMakeLists.txt

@@ -745,6 +745,35 @@ endif()
 
 add_test(NAME RenderCadenceCompositorFrameExchangeTests COMMAND RenderCadenceCompositorFrameExchangeTests)
 
+add_executable(RenderCadenceCompositorClockTests
+	"${RENDER_CADENCE_APP_DIR}/render/RenderCadenceClock.cpp"
+	"${CMAKE_CURRENT_SOURCE_DIR}/tests/RenderCadenceCompositorClockTests.cpp"
+)
+
+target_include_directories(RenderCadenceCompositorClockTests PRIVATE
+	"${RENDER_CADENCE_APP_DIR}/render"
+)
+
+if(MSVC)
+	target_compile_options(RenderCadenceCompositorClockTests PRIVATE /W3)
+endif()
+
+add_test(NAME RenderCadenceCompositorClockTests COMMAND RenderCadenceCompositorClockTests)
+
+add_executable(RenderCadenceCompositorTelemetryTests
+	"${CMAKE_CURRENT_SOURCE_DIR}/tests/RenderCadenceCompositorTelemetryTests.cpp"
+)
+
+target_include_directories(RenderCadenceCompositorTelemetryTests PRIVATE
+	"${RENDER_CADENCE_APP_DIR}/telemetry"
+)
+
+if(MSVC)
+	target_compile_options(RenderCadenceCompositorTelemetryTests PRIVATE /W3)
+endif()
+
+add_test(NAME RenderCadenceCompositorTelemetryTests COMMAND RenderCadenceCompositorTelemetryTests)
+
 add_executable(SystemOutputFramePoolTests
 	"${APP_DIR}/videoio/SystemOutputFramePool.cpp"
 	"${APP_DIR}/videoio/VideoIOFormat.cpp"

apps/RenderCadenceCompositor/README.md

@@ -38,7 +38,8 @@ Included now:
 - latest-N system-memory frame exchange
 - rendered-frame warmup
 - background Slang compile of `shaders/happy-accident`
-- render-thread-only GL commit once compiled shader source is ready
+- app-owned submission of a completed shader artifact
+- render-thread-only GL commit once the artifact is ready
 - compact telemetry
 - non-GL frame-exchange tests
 
@@ -106,9 +107,9 @@ Healthy first-run signs:
 
 ## Runtime Slang Shader Test
 
-On startup the app begins compiling `shaders/happy-accident` on a background thread.
+On startup the app begins compiling `shaders/happy-accident` on a background thread owned by the app orchestration layer.
 
-The render thread keeps drawing the simple motion renderer while Slang compiles. It only attempts the OpenGL shader compile/link once a complete GLSL fragment shader is ready. If either the Slang build or GL commit fails, the app keeps rendering the simple motion fallback.
+The render thread keeps drawing the simple motion renderer while Slang compiles. It does not choose packages, launch Slang, or track build lifecycle. It only receives a completed shader artifact and attempts the OpenGL shader compile/link at a frame boundary. If either the Slang build or GL commit fails, the app keeps rendering the simple motion fallback.
 
 Successful handoff signs:
 

apps/RenderCadenceCompositor/app/RenderCadenceApp.h

@@ -1,11 +1,13 @@
 #pragma once
 
 #include "AppConfig.h"
+#include "../runtime/RuntimeSlangShaderCompiler.h"
 #include "../telemetry/TelemetryPrinter.h"
 #include "../video/DeckLinkOutput.h"
 #include "../video/DeckLinkOutputThread.h"
 
 #include <chrono>
+#include <iostream>
 #include <string>
 #include <thread>
 #include <type_traits>
@@ -78,6 +80,7 @@ public:
 			Stop();
 			return false;
 		}
+		StartRuntimeShaderBuild();
 
 		if (!mFrameExchange.WaitForCompletedDepth(mConfig.warmupCompletedFrames, mConfig.warmupTimeout))
 		{
@@ -116,6 +119,7 @@ public:
 		mTelemetry.Stop();
 		mOutputThread.Stop();
 		mOutput.Stop();
+		StopRuntimeShaderBuild();
 		mRenderThread.Stop();
 		mOutput.ReleaseResources();
 		mStarted = false;
@@ -137,12 +141,47 @@ private:
 		return false;
 	}
 
+	void StartRuntimeShaderBuild()
+	{
+		mShaderCompiler.StartHappyAccidentBuild();
+		mShaderBridgeStopping = false;
+		mShaderBridgeThread = std::thread([this]() { ShaderBridgeMain(); });
+	}
+
+	void StopRuntimeShaderBuild()
+	{
+		mShaderBridgeStopping = true;
+		if (mShaderBridgeThread.joinable())
+			mShaderBridgeThread.join();
+		mShaderCompiler.Stop();
+	}
+
+	void ShaderBridgeMain()
+	{
+		while (!mShaderBridgeStopping)
+		{
+			RuntimeSlangShaderBuild build;
+			if (mShaderCompiler.TryConsume(build))
+			{
+				if (build.succeeded)
+					mRenderThread.SubmitRuntimeShaderArtifact(build.artifact);
+				else
+					std::cout << "Runtime Slang build failed: " << build.message << "\n";
+				return;
+			}
+			std::this_thread::sleep_for(std::chrono::milliseconds(5));
+		}
+	}
+
 	RenderThread& mRenderThread;
 	SystemFrameExchange& mFrameExchange;
 	AppConfig mConfig;
 	DeckLinkOutput mOutput;
 	DeckLinkOutputThread<SystemFrameExchange> mOutputThread;
 	TelemetryPrinter mTelemetry;
+	RuntimeSlangShaderCompiler mShaderCompiler;
+	std::thread mShaderBridgeThread;
+	std::atomic<bool> mShaderBridgeStopping{ false };
 	bool mStarted = false;
 };
 }

apps/RenderCadenceCompositor/render/RenderThread.cpp

@@ -93,7 +93,6 @@ void RenderThread::ThreadMain()
 		SignalStartupFailure("Render pipeline initialization failed.");
 		return;
 	}
-	mSlangCompiler.StartHappyAccidentBuild();
 
 	RenderCadenceClock clock(mConfig.frameDurationMilliseconds);
 	uint64_t frameIndex = 0;
@@ -156,7 +155,6 @@ void RenderThread::ThreadMain()
 	readback.Shutdown();
 	runtimeShaderRenderer.ShutdownGl();
 	renderer.ShutdownGl();
-	mSlangCompiler.Stop();
 	window.ClearCurrent();
 	mRunning.store(false, std::memory_order_release);
 }
@@ -193,23 +191,36 @@ void RenderThread::CountAcquireMiss()
 	++mMetrics.acquireMisses;
 }
 
-void RenderThread::TryCommitReadyRuntimeShader(RuntimeShaderRenderer& runtimeShaderRenderer)
+void RenderThread::SubmitRuntimeShaderArtifact(const RuntimeShaderArtifact& artifact)
 {
-	RuntimeSlangShaderBuild build;
-	if (!mSlangCompiler.TryConsume(build))
+	if (artifact.fragmentShaderSource.empty())
 		return;
 
-	if (!build.succeeded)
-	{
-		std::cout << "Runtime Slang build failed: " << build.message << "\n";
-		OutputDebugStringA(("Runtime Slang build failed: " + build.message + "\n").c_str());
-		std::lock_guard<std::mutex> lock(mMetricsMutex);
-		++mMetrics.shaderBuildFailures;
-		return;
+	std::lock_guard<std::mutex> lock(mShaderArtifactMutex);
+	mPendingShaderArtifact = artifact;
+	mHasPendingShaderArtifact = true;
 }
 
+bool RenderThread::TryTakePendingRuntimeShaderArtifact(RuntimeShaderArtifact& artifact)
+{
+	std::lock_guard<std::mutex> lock(mShaderArtifactMutex);
+	if (!mHasPendingShaderArtifact)
+		return false;
+
+	artifact = std::move(mPendingShaderArtifact);
+	mPendingShaderArtifact = RuntimeShaderArtifact();
+	mHasPendingShaderArtifact = false;
+	return true;
+}
+
+void RenderThread::TryCommitReadyRuntimeShader(RuntimeShaderRenderer& runtimeShaderRenderer)
+{
+	RuntimeShaderArtifact artifact;
+	if (!TryTakePendingRuntimeShaderArtifact(artifact))
+		return;
+
 	std::string commitError;
-	if (!runtimeShaderRenderer.CommitFragmentShader(build.fragmentShaderSource, commitError))
+	if (!runtimeShaderRenderer.CommitFragmentShader(artifact.fragmentShaderSource, commitError))
 	{
 		std::cout << "Runtime shader GL commit failed: " << commitError << "\n";
 		OutputDebugStringA(("Runtime shader GL commit failed: " + commitError + "\n").c_str());
@@ -218,8 +229,8 @@ void RenderThread::TryCommitReadyRuntimeShader(RuntimeShaderRenderer& runtimeSha
 		return;
 	}
 
-	std::cout << "Runtime shader committed: " << build.shaderId << ". " << build.message << "\n";
-	OutputDebugStringA(("Runtime shader committed: " + build.shaderId + ". " + build.message + "\n").c_str());
+	std::cout << "Runtime shader committed: " << artifact.shaderId << ". " << artifact.message << "\n";
+	OutputDebugStringA(("Runtime shader committed: " + artifact.shaderId + ". " + artifact.message + "\n").c_str());
 	std::lock_guard<std::mutex> lock(mMetricsMutex);
 	++mMetrics.shaderBuildsCommitted;
 }

apps/RenderCadenceCompositor/render/RenderThread.h

@@ -1,7 +1,7 @@
 #pragma once
 
 #include "RenderCadenceClock.h"
-#include "../runtime/RuntimeSlangShaderCompiler.h"
+#include "../runtime/RuntimeShaderArtifact.h"
 #include "RuntimeShaderRenderer.h"
 
 #include <atomic>
@@ -44,6 +44,7 @@ public:
 
 	bool Start(std::string& error);
 	void Stop();
+	void SubmitRuntimeShaderArtifact(const RuntimeShaderArtifact& artifact);
 
 	Metrics GetMetrics() const;
 	bool IsRunning() const { return mRunning.load(std::memory_order_acquire); }
@@ -56,10 +57,10 @@ private:
 	void CountCompleted();
 	void CountAcquireMiss();
 	void TryCommitReadyRuntimeShader(RuntimeShaderRenderer& runtimeShaderRenderer);
+	bool TryTakePendingRuntimeShaderArtifact(RuntimeShaderArtifact& artifact);
 
 	SystemFrameExchange& mFrameExchange;
 	Config mConfig;
-	RuntimeSlangShaderCompiler mSlangCompiler;
 	std::thread mThread;
 	std::atomic<bool> mStopping{ false };
 	std::atomic<bool> mRunning{ false };
@@ -71,4 +72,8 @@ private:
 
 	mutable std::mutex mMetricsMutex;
 	Metrics mMetrics;
+
+	std::mutex mShaderArtifactMutex;
+	bool mHasPendingShaderArtifact = false;
+	RuntimeShaderArtifact mPendingShaderArtifact;
 };

apps/RenderCadenceCompositor/runtime/RuntimeShaderArtifact.h

@@ -0,0 +1,10 @@
+#pragma once
+
+#include <string>
+
+struct RuntimeShaderArtifact
+{
+	std::string shaderId;
+	std::string fragmentShaderSource;
+	std::string message;
+};

apps/RenderCadenceCompositor/runtime/RuntimeSlangShaderCompiler.cpp

@@ -89,7 +89,7 @@ bool RuntimeSlangShaderCompiler::TryConsume(RuntimeSlangShaderBuild& build)
 RuntimeSlangShaderBuild RuntimeSlangShaderCompiler::BuildHappyAccident() const
 {
 	RuntimeSlangShaderBuild build;
-	build.shaderId = "happy-accident";
+	build.artifact.shaderId = "happy-accident";
 
 	try
 	{
@@ -126,7 +126,7 @@ RuntimeSlangShaderBuild RuntimeSlangShaderCompiler::BuildHappyAccident() const
 
 		std::string error;
 		const auto start = std::chrono::steady_clock::now();
-		if (!compiler.BuildPassFragmentShaderSource(shaderPackage, pass, build.fragmentShaderSource, error))
+		if (!compiler.BuildPassFragmentShaderSource(shaderPackage, pass, build.artifact.fragmentShaderSource, error))
 		{
 			build.succeeded = false;
 			build.message = error.empty() ? "Happy Accident Slang compile failed." : error;
@@ -136,7 +136,8 @@ RuntimeSlangShaderBuild RuntimeSlangShaderCompiler::BuildHappyAccident() const
 		const auto end = std::chrono::steady_clock::now();
 		const double milliseconds = std::chrono::duration_cast<std::chrono::duration<double, std::milli>>(end - start).count();
 		build.succeeded = true;
-		build.message = "Happy Accident Slang compile completed in " + std::to_string(milliseconds) + " ms.";
+		build.artifact.message = "Happy Accident Slang compile completed in " + std::to_string(milliseconds) + " ms.";
+		build.message = build.artifact.message;
 		return build;
 	}
 	catch (const std::exception& exception)

apps/RenderCadenceCompositor/runtime/RuntimeSlangShaderCompiler.h

@@ -1,5 +1,7 @@
 #pragma once
 
+#include "RuntimeShaderArtifact.h"
+
 #include <atomic>
 #include <mutex>
 #include <string>
@@ -9,8 +11,7 @@ struct RuntimeSlangShaderBuild
 {
 	bool available = false;
 	bool succeeded = false;
-	std::string shaderId;
-	std::string fragmentShaderSource;
+	RuntimeShaderArtifact artifact;
 	std::string message;
 };
 

apps/RenderCadenceCompositor/telemetry/CadenceTelemetry.h

@@ -1,8 +1,5 @@
 #pragma once
 
-#include "../video/DeckLinkOutput.h"
-#include "../video/DeckLinkOutputThread.h"
-
 #include <chrono>
 #include <cstddef>
 #include <cstdint>
@@ -34,10 +31,10 @@ struct CadenceTelemetrySnapshot
 class CadenceTelemetry
 {
 public:
-	template <typename SystemFrameExchange, typename OutputThread>
+	template <typename SystemFrameExchange, typename Output, typename OutputThread>
 	CadenceTelemetrySnapshot Sample(
 		const SystemFrameExchange& exchange,
-		const DeckLinkOutput& output,
+		const Output& output,
 		const OutputThread& outputThread)
 	{
 		const auto now = Clock::now();
@@ -46,7 +43,7 @@ public:
 			: 0.0;
 
 		const auto exchangeMetrics = exchange.Metrics();
-		const DeckLinkOutputMetrics outputMetrics = output.Metrics();
+		const auto outputMetrics = output.Metrics();
 		const auto threadMetrics = outputThread.Metrics();
 
 		CadenceTelemetrySnapshot snapshot;
@@ -80,10 +77,10 @@ public:
 		return snapshot;
 	}
 
-	template <typename SystemFrameExchange, typename OutputThread, typename RenderThread>
+	template <typename SystemFrameExchange, typename Output, typename OutputThread, typename RenderThread>
 	CadenceTelemetrySnapshot Sample(
 		const SystemFrameExchange& exchange,
-		const DeckLinkOutput& output,
+		const Output& output,
 		const OutputThread& outputThread,
 		const RenderThread& renderThread)
 	{

apps/RenderCadenceCompositor/telemetry/TelemetryPrinter.h

@@ -31,8 +31,8 @@ public:
 		Stop();
 	}
 
-	template <typename SystemFrameExchange, typename OutputThread, typename RenderThread>
-	void Start(const SystemFrameExchange& exchange, const DeckLinkOutput& output, const OutputThread& outputThread, const RenderThread& renderThread)
+	template <typename SystemFrameExchange, typename Output, typename OutputThread, typename RenderThread>
+	void Start(const SystemFrameExchange& exchange, const Output& output, const OutputThread& outputThread, const RenderThread& renderThread)
 	{
 		if (mRunning)
 			return;

tests/RenderCadenceCompositorClockTests.cpp

@@ -0,0 +1,94 @@
+#include "RenderCadenceClock.h"
+
+#include <chrono>
+#include <iostream>
+
+namespace
+{
+int gFailures = 0;
+
+void Expect(bool condition, const char* message)
+{
+	if (condition)
+		return;
+
+	std::cerr << "FAIL: " << message << "\n";
+	++gFailures;
+}
+
+void TestEarlyPollWaitsWithoutAdvancing()
+{
+	using Clock = RenderCadenceClock::Clock;
+	RenderCadenceClock cadence(16.0);
+	const auto start = Clock::now();
+	cadence.Reset(start);
+
+	const auto tick = cadence.Poll(start - std::chrono::milliseconds(1));
+	Expect(!tick.due, "early poll is not due");
+	Expect(tick.sleepFor > RenderCadenceClock::Duration::zero(), "early poll returns a sleep duration");
+	Expect(cadence.OverrunCount() == 0, "early poll does not count overrun");
+	Expect(cadence.SkippedFrameCount() == 0, "early poll does not skip frames");
+}
+
+void TestDuePollRendersWithoutSkipping()
+{
+	using Clock = RenderCadenceClock::Clock;
+	RenderCadenceClock cadence(16.0);
+	const auto start = Clock::now();
+	cadence.Reset(start);
+
+	const auto tick = cadence.Poll(start);
+	Expect(tick.due, "exact cadence time is due");
+	Expect(tick.skippedFrames == 0, "exact cadence time skips no frames");
+	Expect(cadence.OverrunCount() == 0, "exact cadence time is not an overrun");
+
+	cadence.MarkRendered(start);
+	Expect(cadence.NextRenderTime() > start, "mark rendered advances next render time");
+}
+
+void TestLatePollRecordsSkippedFrames()
+{
+	using Clock = RenderCadenceClock::Clock;
+	RenderCadenceClock cadence(10.0);
+	const auto start = Clock::now();
+	cadence.Reset(start);
+
+	const auto tick = cadence.Poll(start + std::chrono::milliseconds(35));
+	Expect(tick.due, "late poll is due");
+	Expect(tick.skippedFrames == 3, "late poll records skipped frame intervals");
+	Expect(cadence.OverrunCount() == 1, "late poll records overrun");
+	Expect(cadence.SkippedFrameCount() == 3, "late poll accumulates skipped frames");
+}
+
+void TestMarkRenderedRebasesAfterLargeStall()
+{
+	using Clock = RenderCadenceClock::Clock;
+	RenderCadenceClock cadence(10.0);
+	const auto start = Clock::now();
+	cadence.Reset(start);
+
+	const auto stalled = start + std::chrono::milliseconds(100);
+	cadence.MarkRendered(stalled);
+
+	const auto next = cadence.NextRenderTime();
+	Expect(next > stalled, "large stall rebases next render time after now");
+	Expect(next - stalled <= std::chrono::milliseconds(11), "large stall rebases to roughly one frame ahead");
+}
+}
+
+int main()
+{
+	TestEarlyPollWaitsWithoutAdvancing();
+	TestDuePollRendersWithoutSkipping();
+	TestLatePollRecordsSkippedFrames();
+	TestMarkRenderedRebasesAfterLargeStall();
+
+	if (gFailures != 0)
+	{
+		std::cerr << gFailures << " cadence clock test failure(s).\n";
+		return 1;
+	}
+
+	std::cout << "RenderCadenceCompositor cadence clock tests passed.\n";
+	return 0;
+}

tests/RenderCadenceCompositorTelemetryTests.cpp

@@ -0,0 +1,146 @@
+#include "CadenceTelemetry.h"
+
+#include <chrono>
+#include <cstdint>
+#include <iostream>
+#include <thread>
+
+namespace
+{
+int gFailures = 0;
+
+void Expect(bool condition, const char* message)
+{
+	if (condition)
+		return;
+
+	std::cerr << "FAIL: " << message << "\n";
+	++gFailures;
+}
+
+struct FakeExchangeMetrics
+{
+	std::size_t freeCount = 0;
+	std::size_t completedCount = 0;
+	std::size_t scheduledCount = 0;
+	uint64_t completedFrames = 0;
+	uint64_t scheduledFrames = 0;
+};
+
+struct FakeExchange
+{
+	FakeExchangeMetrics metrics;
+	FakeExchangeMetrics Metrics() const { return metrics; }
+};
+
+struct FakeOutputThreadMetrics
+{
+	uint64_t completedPollMisses = 0;
+	uint64_t scheduleFailures = 0;
+};
+
+struct FakeOutputThread
+{
+	FakeOutputThreadMetrics metrics;
+	FakeOutputThreadMetrics Metrics() const { return metrics; }
+};
+
+struct FakeOutputMetrics
+{
+	uint64_t completions = 0;
+	uint64_t displayedLate = 0;
+	uint64_t dropped = 0;
+	uint64_t scheduleFailures = 0;
+	bool actualBufferedFramesAvailable = false;
+	uint64_t actualBufferedFrames = 0;
+	double scheduleCallMilliseconds = 0.0;
+};
+
+struct FakeOutput
+{
+	FakeOutputMetrics metrics;
+	FakeOutputMetrics Metrics() const { return metrics; }
+};
+
+struct FakeRenderThreadMetrics
+{
+	uint64_t shaderBuildsCommitted = 0;
+	uint64_t shaderBuildFailures = 0;
+};
+
+struct FakeRenderThread
+{
+	FakeRenderThreadMetrics metrics;
+	FakeRenderThreadMetrics GetMetrics() const { return metrics; }
+};
+
+void TestTelemetrySamplesCompletedPollMissesAndShaderCounts()
+{
+	RenderCadenceCompositor::CadenceTelemetry telemetry;
+	FakeExchange exchange;
+	exchange.metrics.freeCount = 7;
+	exchange.metrics.completedCount = 1;
+	exchange.metrics.scheduledCount = 4;
+	exchange.metrics.completedFrames = 100;
+	exchange.metrics.scheduledFrames = 96;
+
+	FakeOutput output;
+	output.metrics.actualBufferedFramesAvailable = true;
+	output.metrics.actualBufferedFrames = 4;
+
+	FakeOutputThread outputThread;
+	outputThread.metrics.completedPollMisses = 12;
+	outputThread.metrics.scheduleFailures = 0;
+
+	FakeRenderThread renderThread;
+	renderThread.metrics.shaderBuildsCommitted = 1;
+	renderThread.metrics.shaderBuildFailures = 0;
+
+	const auto snapshot = telemetry.Sample(exchange, output, outputThread, renderThread);
+	Expect(snapshot.freeFrames == 7, "free frame count is sampled");
+	Expect(snapshot.completedFrames == 1, "completed frame count is sampled");
+	Expect(snapshot.scheduledFrames == 4, "scheduled frame count is sampled");
+	Expect(snapshot.completedPollMisses == 12, "completed poll misses are sampled");
+	Expect(snapshot.shaderBuildsCommitted == 1, "shader committed count is sampled");
+	Expect(snapshot.shaderBuildFailures == 0, "shader failure count is sampled");
+	Expect(snapshot.deckLinkBufferedAvailable, "buffer telemetry availability is sampled");
+	Expect(snapshot.deckLinkBuffered == 4, "buffer depth is sampled");
+}
+
+void TestTelemetryComputesRatesFromDeltas()
+{
+	RenderCadenceCompositor::CadenceTelemetry telemetry;
+	FakeExchange exchange;
+	FakeOutput output;
+	FakeOutputThread outputThread;
+	FakeRenderThread renderThread;
+
+	exchange.metrics.completedFrames = 10;
+	exchange.metrics.scheduledFrames = 10;
+	(void)telemetry.Sample(exchange, output, outputThread, renderThread);
+
+	std::this_thread::sleep_for(std::chrono::milliseconds(5));
+
+	exchange.metrics.completedFrames = 20;
+	exchange.metrics.scheduledFrames = 19;
+	const auto snapshot = telemetry.Sample(exchange, output, outputThread, renderThread);
+	Expect(snapshot.sampleSeconds > 0.0, "second telemetry sample has elapsed time");
+	Expect(snapshot.renderFps > 0.0, "render fps is computed from completed frame delta");
+	Expect(snapshot.scheduleFps > 0.0, "schedule fps is computed from scheduled frame delta");
+}
+}
+
+int main()
+{
+	TestTelemetrySamplesCompletedPollMissesAndShaderCounts();
+	TestTelemetryComputesRatesFromDeltas();
+
+	if (gFailures != 0)
+	{
+		std::cerr << gFailures << " telemetry test failure(s).\n";
+		return 1;
+	}
+
+	std::cout << "RenderCadenceCompositor telemetry tests passed.\n";
+	return 0;
+}