Create offscreen context at startup and reuse it.

common/lc_application.cpp

@@ -772,6 +772,11 @@ lcStartupMode lcApplication::Initialize(QList<QPair<QString, bool>>& LibraryPath
 #endif
 	}
 
+#ifdef LC_USE_QOPENGLWIDGET
+	if (!lcContext::CreateOffscreenContext())
+		return lcStartupMode::Error;
+#endif
+
 	gMainWindow = new lcMainWindow();
 	lcLoadDefaultKeyboardShortcuts();
 	lcLoadDefaultMouseShortcuts();

common/lc_context.cpp

@@ -27,6 +27,10 @@
 #define GL_STATIC_DRAW_ARB GL_STATIC_DRAW
 #endif
 
+#ifdef LC_USE_QOPENGLWIDGET
+std::unique_ptr<QOpenGLContext> lcContext::mOffscreenContext;
+std::unique_ptr<QOffscreenSurface> lcContext::mOffscreenSurface;
+#endif
 lcProgram lcContext::mPrograms[static_cast<int>(lcMaterialType::Count)];
 int lcContext::mValidContexts;
 
@@ -93,6 +97,47 @@ lcContext::~lcContext()
 	}
 }
 
+#ifdef LC_USE_QOPENGLWIDGET
+
+bool lcContext::CreateOffscreenContext()
+{
+	std::unique_ptr<QOpenGLContext> OffscreenContext(new QOpenGLContext());
+
+	if (!OffscreenContext)
+		return false;
+
+	OffscreenContext->setShareContext(QOpenGLContext::globalShareContext());
+
+	if (!OffscreenContext->create() || !OffscreenContext->isValid())
+		return false;
+
+	std::unique_ptr<QOffscreenSurface> OffscreenSurface(new QOffscreenSurface());
+
+	if (!OffscreenSurface)
+		return false;
+
+	OffscreenSurface->create();
+
+	if (!OffscreenSurface->isValid())
+		return false;
+
+	if (!OffscreenContext->makeCurrent(OffscreenSurface.get()))
+		return false;
+
+	mOffscreenContext = std::move(OffscreenContext);
+	mOffscreenSurface = std::move(OffscreenSurface);
+
+	return true;
+}
+
+void lcContext::DestroyOffscreenContext()
+{
+	mOffscreenSurface.reset();
+	mOffscreenContext.reset();
+}
+
+#endif
+
 void lcContext::CreateShaderPrograms()
 {
 	const char* ShaderPrefix =
@@ -255,20 +300,33 @@ void lcContext::DestroyResources()
 	}
 }
 
+void lcContext::MakeCurrent()
+{
+	if (mWidget)
+		mWidget->makeCurrent();
 #ifdef LC_USE_QOPENGLWIDGET
-void lcContext::SetGLContext(QOpenGLContext* GLContext)
+	else
+		mOffscreenContext->makeCurrent(mOffscreenSurface.get());
+#endif
+}
+
+#ifdef LC_USE_QOPENGLWIDGET
+void lcContext::SetGLContext(QOpenGLContext* Context, QOpenGLWidget* Widget)
 #else
-void lcContext::SetGLContext(const QGLContext* GLContext)
+void lcContext::SetGLContext(const QGLContext* Context, QGLWidget* Widget)
 #endif
 {
+	mContext = Context;
+	mWidget = Widget;
+
 #ifdef LC_USE_QOPENGLWIDGET
+	MakeCurrent();
 	initializeOpenGLFunctions();
-	mGLContext = GLContext;
 #endif
 
 	if (!mValidContexts)
 	{
-		lcInitializeGLExtensions(GLContext);
+		lcInitializeGLExtensions(Context);
 
 		// TODO: Find a better place for the grid texture and font
 		gStringCache.Initialize(this);
@@ -289,6 +347,15 @@ void lcContext::SetGLContext(const QGLContext* GLContext)
 	mValidContexts++;
 }
 
+#ifdef LC_USE_QOPENGLWIDGET
+
+void lcContext::SetOffscreenContext()
+{
+	SetGLContext(mOffscreenContext.get(), nullptr);
+}
+
+#endif
+
 void lcContext::SetDefaultState()
 {
 #ifdef LC_USE_QOPENGLWIDGET
@@ -610,7 +677,7 @@ void lcContext::ClearFramebuffer()
 		return;
 
 #ifdef LC_USE_QOPENGLWIDGET
-	glBindFramebuffer(GL_FRAMEBUFFER, mGLContext->defaultFramebufferObject());
+	glBindFramebuffer(GL_FRAMEBUFFER, mContext->defaultFramebufferObject());
 #else
 	if (gSupportsFramebufferObjectARB)
 		glBindFramebuffer(GL_FRAMEBUFFER, 0);
@@ -664,7 +731,7 @@ lcFramebuffer lcContext::CreateFramebuffer(int Width, int Height, bool Depth, bo
 #ifdef LC_USE_QOPENGLWIDGET
 		else
 		{
-			QOpenGLFunctions_3_2_Core* Funcs = mGLContext->versionFunctions<QOpenGLFunctions_3_2_Core>();
+			QOpenGLFunctions_3_2_Core* Funcs = mContext->versionFunctions<QOpenGLFunctions_3_2_Core>();
 
 			BindTexture2DMS(Framebuffer.mColorTexture);
 			Funcs->glTexImage2DMultisample(GL_TEXTURE_2D_MULTISAMPLE, Samples, GL_RGBA, Width, Height, GL_TRUE);
@@ -824,7 +891,7 @@ void lcContext::GetRenderFramebufferImage(const std::pair<lcFramebuffer, lcFrame
 		glBindFramebuffer(GL_READ_FRAMEBUFFER, RenderFramebuffer.first.mObject);
 
 #ifdef LC_USE_QOPENGLWIDGET
-		QOpenGLFunctions_3_2_Core* Funcs = mGLContext->versionFunctions<QOpenGLFunctions_3_2_Core>();
+		QOpenGLFunctions_3_2_Core* Funcs = mContext->versionFunctions<QOpenGLFunctions_3_2_Core>();
 		Funcs->glBlitFramebuffer(0, 0, Width, Height, 0, 0, Width, Height, GL_COLOR_BUFFER_BIT, GL_LINEAR);
 #else
 		glBlitFramebuffer(0, 0, Width, Height, 0, 0, Width, Height, GL_COLOR_BUFFER_BIT, GL_LINEAR);

common/lc_context.h

@@ -120,16 +120,23 @@ public:
 	lcContext(const lcContext&) = delete;
 	lcContext& operator=(const lcContext&) = delete;
 
+#ifdef LC_USE_QOPENGLWIDGET
+	static bool CreateOffscreenContext();
+	static void DestroyOffscreenContext();
+#endif
+
 	void CreateResources();
 	void DestroyResources();
 
 	void SetDefaultState();
 	void ClearResources();
 
+	void MakeCurrent();
 #ifdef LC_USE_QOPENGLWIDGET
-	void SetGLContext(QOpenGLContext* GLContext);
+	void SetGLContext(QOpenGLContext* GLContext, QOpenGLWidget* Widget);
+	void SetOffscreenContext();
 #else
-	void SetGLContext(const QGLContext* GLContext);
+	void SetGLContext(const QGLContext* GLContext, QGLWidget* Widget);
 #endif
 
 	void ClearColorAndDepth(const lcVector4& ClearColor);
@@ -234,7 +241,8 @@ protected:
 	void FlushState();
 
 #ifdef LC_USE_QOPENGLWIDGET
-	QOpenGLContext* mGLContext = nullptr;
+	QOpenGLWidget* mWidget = nullptr;
+	QOpenGLContext* mContext = nullptr;
 #endif
 	bool mValid = false;
 
@@ -273,6 +281,11 @@ protected:
 
 	GLuint mFramebufferObject;
 
+#ifdef LC_USE_QOPENGLWIDGET
+	static std::unique_ptr<QOpenGLContext> mOffscreenContext;
+	static std::unique_ptr<QOffscreenSurface> mOffscreenSurface;
+#endif
+
 	static lcProgram mPrograms[static_cast<int>(lcMaterialType::Count)];
 	static int mValidContexts;
 

common/lc_model.cpp

@@ -1276,9 +1276,12 @@ QImage lcModel::GetStepImage(bool Zoom, int Width, int Height, lcStep Step)
 	lcCamera* Camera = ActiveView->GetCamera();
 
 	lcView View(lcViewType::View, this);
-	View.SetCamera(Camera, false);
+	View.SetCamera(Camera, true);
 
-#ifndef LC_USE_QOPENGLWIDGET
+#ifdef LC_USE_QOPENGLWIDGET
+	View.SetOffscreenContext();
+	View.MakeCurrent();
+#else
 	ActiveView->MakeCurrent();
 	lcContext* Context = ActiveView->mContext;
 	View.SetContext(Context);

common/lc_partselectionwidget.cpp

@@ -398,6 +398,9 @@ void lcPartSelectionListModel::DrawPreview(int InfoIndex)
 	{
 		mView = std::unique_ptr<lcView>(new lcView(lcViewType::PartsList, nullptr));
 
+		mView->SetOffscreenContext();
+		mView->MakeCurrent();
+
 		if (!mView->BeginRenderToImage(Width, Height))
 		{
 			mView.reset();
@@ -406,6 +409,7 @@ void lcPartSelectionListModel::DrawPreview(int InfoIndex)
 	}
 
 	mView->MakeCurrent();
+	mView->BindRenderFramebuffer();
 
 	lcContext* Context = mView->mContext;
 #else
@@ -456,6 +460,7 @@ void lcPartSelectionListModel::DrawPreview(int InfoIndex)
 	Scene.Draw(Context);
 
 #ifdef LC_USE_QOPENGLWIDGET
+	mView->UnbindRenderFramebuffer();
 	QImage Image = mView->GetRenderFramebufferImage().convertToFormat(QImage::Format_ARGB32);
 #else
 	QImage Image = Context->GetRenderFramebufferImage(mRenderFramebuffer);

common/lc_view.cpp

@@ -76,12 +76,7 @@ void lcView::UpdateAllViews()
 
 void lcView::MakeCurrent()
 {
-	if (mWidget)
-		mWidget->makeCurrent();
-#ifdef LC_USE_QOPENGLWIDGET
-	else if (mOffscreenContext)
-		mOffscreenContext->makeCurrent(mOffscreenSurface.get());
-#endif
+	mContext->MakeCurrent();
 }
 
 void lcView::Redraw()
@@ -90,6 +85,15 @@ void lcView::Redraw()
 		mWidget->update();
 }
 
+#ifdef LC_USE_QOPENGLWIDGET
+
+void lcView::SetOffscreenContext()
+{
+	mContext->SetOffscreenContext();
+}
+
+#else
+
 void lcView::SetContext(lcContext* Context)
 {
 	if (mDeleteContext)
@@ -99,6 +103,8 @@ void lcView::SetContext(lcContext* Context)
 	mDeleteContext = false;
 }
 
+#endif
+
 void lcView::SetFocus(bool Focus)
 {
 	if (Focus)
@@ -725,36 +731,6 @@ lcArray<lcObject*> lcView::FindObjectsInBox(float x1, float y1, float x2, float
 
 bool lcView::BeginRenderToImage(int Width, int Height)
 {
-#ifdef LC_USE_QOPENGLWIDGET
-	std::unique_ptr<QOpenGLContext> OffscreenContext(new QOpenGLContext());
-
-	if (!OffscreenContext)
-		return false;
-
-	OffscreenContext->setShareContext(QOpenGLContext::globalShareContext());
-
-	if (!OffscreenContext->create() || !OffscreenContext->isValid())
-		return false;
-
-	std::unique_ptr<QOffscreenSurface> OffscreenSurface(new QOffscreenSurface());
-
-	if (!OffscreenSurface)
-		return false;
-
-	OffscreenSurface->create();
-
-	if (!OffscreenSurface->isValid())
-		return false;
-
-	if (!OffscreenContext->makeCurrent(OffscreenSurface.get()))
-		return false;
-
-	mContext->SetGLContext(OffscreenContext.get());
-
-	mOffscreenContext = std::move(OffscreenContext);
-	mOffscreenSurface = std::move(OffscreenSurface);
-#endif
-
 	GLint MaxTexture;
 	glGetIntegerv(GL_MAX_TEXTURE_SIZE, &MaxTexture);
 
@@ -795,8 +771,6 @@ bool lcView::BeginRenderToImage(int Width, int Height)
 void lcView::EndRenderToImage()
 {
 #ifdef LC_USE_QOPENGLWIDGET
-	mOffscreenContext.reset();
-	mOffscreenSurface.reset();
 	mRenderFramebuffer.reset();
 #else
 	mRenderImage = QImage();
@@ -812,13 +786,19 @@ QImage lcView::GetRenderImage() const
 
 #ifdef LC_USE_QOPENGLWIDGET
 
-QImage lcView::GetRenderFramebufferImage() const
+void lcView::BindRenderFramebuffer()
+{
+	mRenderFramebuffer->bind();
+}
+
+void lcView::UnbindRenderFramebuffer()
 {
 	mRenderFramebuffer->release();
-	QImage Image = mRenderFramebuffer->toImage();
-	mRenderFramebuffer->bind();
+}
 
-	return Image;
+QImage lcView::GetRenderFramebufferImage() const
+{
+	return mRenderFramebuffer->toImage();
 }
 
 #endif
@@ -918,7 +898,9 @@ void lcView::OnDraw()
 			if (!mRenderImage.isNull())
 			{
 #ifdef LC_USE_QOPENGLWIDGET
+				UnbindRenderFramebuffer();
 				QImage TileImage = GetRenderFramebufferImage();
+				BindRenderFramebuffer();
 				quint8* Buffer = TileImage.bits();
 #else
 				quint8* Buffer = (quint8*)malloc(mWidth * mHeight * 4);

common/lc_view.h

@@ -176,7 +176,12 @@ public:
 
 	void MakeCurrent();
 	void Redraw();
+
+#ifdef LC_USE_QOPENGLWIDGET
+	void SetOffscreenContext();
+#else
 	void SetContext(lcContext* Context);
+#endif
 
 	void SetFocus(bool Focus);
 	void SetMousePosition(int MouseX, int MouseY);
@@ -236,6 +241,8 @@ public:
 	void EndRenderToImage();
 	QImage GetRenderImage() const;
 #ifdef LC_USE_QOPENGLWIDGET
+	void BindRenderFramebuffer();
+	void UnbindRenderFramebuffer();
 	QImage GetRenderFramebufferImage() const;
 #endif
 
@@ -300,8 +307,6 @@ protected:
 
 	QImage mRenderImage;
 #ifdef LC_USE_QOPENGLWIDGET
-	std::unique_ptr<QOpenGLContext> mOffscreenContext;
-	std::unique_ptr<QOffscreenSurface> mOffscreenSurface;
 	std::unique_ptr<QOpenGLFramebufferObject> mRenderFramebuffer;
 #else
 	std::pair<lcFramebuffer, lcFramebuffer> mRenderFramebuffer;

common/lc_viewwidget.cpp

@@ -56,7 +56,7 @@ void lcViewWidget::SetView(lcView* View)
 		if (context())
 		{
 			makeCurrent();
-			View->mContext->SetGLContext(context());
+			View->mContext->SetGLContext(context(), this);
 		}
 
 		View->SetWidget(this);
@@ -73,7 +73,7 @@ void lcViewWidget::SetView(lcView* View)
 
 void lcViewWidget::initializeGL()
 {
-	mView->mContext->SetGLContext(context());
+	mView->mContext->SetGLContext(context(), this);
 }
 
 void lcViewWidget::resizeGL(int Width, int Height)

qt/qtmain.cpp

@@ -3,6 +3,7 @@
 #include "lc_qupdatedialog.h"
 #include "lc_mainwindow.h"
 #include "lc_profile.h"
+#include "lc_context.h"
 #include <QApplication>
 #include <locale.h>
 
@@ -197,6 +198,10 @@ int main(int argc, char *argv[])
 		ExecReturn = Application.exec();
 	}
 
+#ifdef LC_USE_QOPENGLWIDGET
+	lcContext::DestroyOffscreenContext();
+#endif
+
 	delete gMainWindow;
 	gMainWindow = nullptr;