From 92a588b0603af4811082f609f192f4fcea68465c Mon Sep 17 00:00:00 2001
From: f4exb <f4exb06@gmail.com>
Date: Sun, 6 Mar 2016 10:48:34 +0100
Subject: [PATCH] OpenGL modernization: GLScope: enhance openGL context
 checking and debugging at initializeGL time

---
 include/gui/glshadersimple.h |  1 +
 sdrbase/gui/glscope.cpp      | 28 ++++++++++++++++++++++++++--
 2 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/include/gui/glshadersimple.h b/include/gui/glshadersimple.h
index 65b370f5f..633f621f8 100644
--- a/include/gui/glshadersimple.h
+++ b/include/gui/glshadersimple.h
@@ -19,6 +19,7 @@
 #define INCLUDE_GUI_GLSHADERSIMPLE_H_
 
 #include <QString>
+#include <QOpenGLFunctions>
 
 class QOpenGLShaderProgram;
 class QMatrix4x4;
diff --git a/sdrbase/gui/glscope.cpp b/sdrbase/gui/glscope.cpp
index a928d2aab..4c13a93c0 100644
--- a/sdrbase/gui/glscope.cpp
+++ b/sdrbase/gui/glscope.cpp
@@ -21,6 +21,7 @@
 #include <QMouseEvent>
 #include <QOpenGLContext>
 #include <QOpenGLFunctions>
+#include <QSurface>
 #include "gui/glscope.h"
 #include "dsp/dspengine.h"
 
@@ -239,6 +240,7 @@ void GLScope::newTrace(const std::vector<Complex>& trace, int sampleRate)
 void GLScope::initializeGL()
 {
 	QOpenGLContext *glCurrentContext =  QOpenGLContext::currentContext();
+	//QOpenGLContext *glCurrentContext =  context();
 
 	if (glCurrentContext) {
 		if (QOpenGLContext::currentContext()->isValid()) {
@@ -255,6 +257,28 @@ void GLScope::initializeGL()
 		return;
 	}
 
+	QSurface *surface = glCurrentContext->surface();
+
+	if (surface == 0)
+	{
+		qCritical() << "GLScope::initializeGL: no surface attached";
+		return;
+	}
+	else
+	{
+		if (surface->surfaceType() != QSurface::OpenGLSurface)
+		{
+			qCritical() << "GLScope::initializeGL: surface is not an OpenGLSurface: " << surface->surfaceType()
+				<< " cannot use an OpenGL context";
+			return;
+		}
+		else
+		{
+			qDebug() << "GLScope::initializeGL: OpenGL surface:"
+				<< " class: " << (surface->surfaceClass() == QSurface::Window ? "Window" : "Offscreen");
+		}
+	}
+
 	connect(glCurrentContext, &QOpenGLContext::aboutToBeDestroyed, this, &GLScope::cleanup); // TODO: when migrating to QOpenGLWidget
 
 	QOpenGLFunctions *glFunctions = QOpenGLContext::currentContext()->functions();
@@ -2825,12 +2849,12 @@ void GLScope::connectTimer(const QTimer& timer)
 
 void GLScope::cleanup()
 {
-	makeCurrent();
+	//makeCurrent();
 	m_glShaderSimple.cleanup();
 	m_glShaderBottom1Scale.cleanup();
 	m_glShaderBottom2Scale.cleanup();
 	m_glShaderLeft1Scale.cleanup();
 	m_glShaderPowerOverlay.cleanup();
-    doneCurrent();
+    //doneCurrent();
 }