Shader compile thread seperation

apps/LoopThroughWithOpenGLCompositing/gl/OpenGLComposite.cpp

@@ -8,6 +8,7 @@
 #include "OpenGLRenderPass.h"
 #include "OpenGLShaderPrograms.h"
 #include "RuntimeServices.h"
+#include "ShaderBuildQueue.h"
 
 #include <memory>
 #include <string>
@@ -16,7 +17,8 @@
 OpenGLComposite::OpenGLComposite(HWND hWnd, HDC hDC, HGLRC hRC) :
 	hGLWnd(hWnd), hGLDC(hDC), hGLRC(hRC),
 	mDeckLink(std::make_unique<DeckLinkSession>()),
-	mRenderer(std::make_unique<OpenGLRenderer>())
+	mRenderer(std::make_unique<OpenGLRenderer>()),
+	mUseCommittedLayerStates(false)
 {
 	InitializeCriticalSection(&pMutex);
 	mRuntimeHost = std::make_unique<RuntimeHost>();
@@ -31,6 +33,7 @@ OpenGLComposite::OpenGLComposite(HWND hWnd, HDC hDC, HGLRC hRC) :
 		[this]() { paintGL(); });
 	mRenderPass = std::make_unique<OpenGLRenderPass>(*mRenderer);
 	mShaderPrograms = std::make_unique<OpenGLShaderPrograms>(*mRenderer, *mRuntimeHost);
+	mShaderBuildQueue = std::make_unique<ShaderBuildQueue>(*mRuntimeHost);
 	mRuntimeServices = std::make_unique<RuntimeServices>();
 }
 
@@ -38,6 +41,8 @@ OpenGLComposite::~OpenGLComposite()
 {
 	if (mRuntimeServices)
 		mRuntimeServices->Stop();
+	if (mShaderBuildQueue)
+		mShaderBuildQueue->Stop();
 	mDeckLink->ReleaseResources();
 	mRenderer->DestroyResources();
 
@@ -223,6 +228,8 @@ bool OpenGLComposite::InitOpenGLState()
 		MessageBoxA(NULL, compilerErrorMessage, "OpenGL shader failed to load or compile", MB_OK);
 		return false;
 	}
+	mCachedLayerRenderStates = mShaderPrograms->CommittedLayerStates();
+	mUseCommittedLayerStates = false;
 	mShaderPrograms->ResetTemporalHistoryState();
 
 	std::string rendererError;
@@ -268,32 +275,14 @@ bool OpenGLComposite::Stop()
 
 bool OpenGLComposite::ReloadShader()
 {
-	char compilerErrorMessage[1024];
-
-	EnterCriticalSection(&pMutex);
-	wglMakeCurrent(hGLDC, hGLRC);
-
-	bool success = mShaderPrograms->CompileLayerPrograms(mDeckLink->InputFrameWidth(), mDeckLink->InputFrameHeight(), sizeof(compilerErrorMessage), compilerErrorMessage);
 	if (mRuntimeHost)
+	{
+		mRuntimeHost->SetCompileStatus(true, "Shader rebuild queued.");
 		mRuntimeHost->ClearReloadRequest();
-
-	wglMakeCurrent(NULL, NULL);
-	LeaveCriticalSection(&pMutex);
-
-	if (!success)
-	{
-		if (mRuntimeHost)
-			mRuntimeHost->SetCompileStatus(false, compilerErrorMessage);
-		MessageBoxA(NULL, compilerErrorMessage, "Slang shader reload failed", MB_OK);
 	}
-	else
-	{
-		if (mRuntimeHost)
-			mRuntimeHost->SetCompileStatus(true, "Shader compiled successfully.");
-		broadcastRuntimeState();
-	}
-
-	return success;
+	RequestShaderBuild();
+	broadcastRuntimeState();
+	return true;
 }
 
 void OpenGLComposite::renderEffect()
@@ -302,7 +291,11 @@ void OpenGLComposite::renderEffect()
 
 	const bool hasInputSource = mDeckLink->HasInputSource();
 	std::vector<RuntimeRenderState> layerStates;
-	if (mRuntimeHost)
+	if (mUseCommittedLayerStates)
+	{
+		layerStates = mShaderPrograms->CommittedLayerStates();
+	}
+	else if (mRuntimeHost)
 	{
 		if (mRuntimeHost->TryGetLayerRenderStates(mDeckLink->InputFrameWidth(), mDeckLink->InputFrameHeight(), layerStates))
 			mCachedLayerRenderStates = layerStates;
@@ -341,22 +334,44 @@ bool OpenGLComposite::ProcessRuntimePollResults()
 		broadcastRuntimeState();
 
 	if (!events.reloadRequested)
-		return true;
-
-	char compilerErrorMessage[1024] = {};
-	if (!mShaderPrograms->CompileLayerPrograms(mDeckLink->InputFrameWidth(), mDeckLink->InputFrameHeight(), sizeof(compilerErrorMessage), compilerErrorMessage))
 	{
-		mRuntimeHost->SetCompileStatus(false, compilerErrorMessage);
-		mRuntimeHost->ClearReloadRequest();
+		PreparedShaderBuild readyBuild;
+		if (!mShaderBuildQueue || !mShaderBuildQueue->TryConsumeReadyBuild(readyBuild))
+			return true;
+
+		char compilerErrorMessage[1024] = {};
+		if (!mShaderPrograms->CommitPreparedLayerPrograms(readyBuild, mDeckLink->InputFrameWidth(), mDeckLink->InputFrameHeight(), sizeof(compilerErrorMessage), compilerErrorMessage))
+		{
+			mRuntimeHost->SetCompileStatus(false, compilerErrorMessage);
+			mUseCommittedLayerStates = true;
+			broadcastRuntimeState();
+			return false;
+		}
+
+		mUseCommittedLayerStates = false;
+		mCachedLayerRenderStates = mShaderPrograms->CommittedLayerStates();
+		mShaderPrograms->ResetTemporalHistoryState();
 		broadcastRuntimeState();
-		return false;
+		return true;
 	}
 
-	mShaderPrograms->ResetTemporalHistoryState();
+	mRuntimeHost->SetCompileStatus(true, "Shader rebuild queued.");
+	RequestShaderBuild();
 	broadcastRuntimeState();
 	return true;
 }
 
+void OpenGLComposite::RequestShaderBuild()
+{
+	if (!mShaderBuildQueue || !mDeckLink)
+		return;
+
+	mUseCommittedLayerStates = true;
+	if (mRuntimeHost)
+		mRuntimeHost->ClearReloadRequest();
+	mShaderBuildQueue->RequestBuild(mDeckLink->InputFrameWidth(), mDeckLink->InputFrameHeight());
+}
+
 void OpenGLComposite::broadcastRuntimeState()
 {
 	if (mRuntimeServices)