Make sure the context is current when needed

Task-number: QTBUG-44148
Change-Id: Ia15592328638dd243b7f82d8e2dcc7e523447cbf
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>

3 files changed, 24 insertions, 7 deletions

diff --git a/src/render/backend/qgraphicscontext.cpp b/src/render/backend/qgraphicscontext.cpp
index 75eb217c2..7145d5451 100644
--- a/src/render/backend/qgraphicscontext.cpp
+++ b/src/render/backend/qgraphicscontext.cpp
@@ -144,11 +144,8 @@ bool QGraphicsContext::beginDrawing(QSurface *surface, const QColor &clearColor)
             return false;
     }
 
-    bool ok = m_gl->makeCurrent(m_surface);
-    if (!ok) {
-        qCWarning(Backend) << Q_FUNC_INFO << "make current failed";
+    if (!makeCurrent(m_surface))
         return false;
-    }
 
     GLint err = m_gl->functions()->glGetError();
     if (err != 0) {
@@ -234,8 +231,25 @@ void QGraphicsContext::setOpenGLContext(QOpenGLContext* ctx, QSurface *surface)
     releaseOpenGL();
     m_gl = ctx;
 
-    m_gl->makeCurrent(surface);
-    resolveHighestOpenGLFunctions();
+    if (makeCurrent(surface)) {
+        resolveHighestOpenGLFunctions();
+        m_gl->doneCurrent();
+    }
+}
+
+bool QGraphicsContext::makeCurrent(QSurface *surface)
+{
+    Q_ASSERT(m_gl);
+    if (!m_gl->makeCurrent(surface)) {
+        qCWarning(Backend) << Q_FUNC_INFO << "makeCurrent failed";
+        return false;
+    }
+    return true;
+}
+
+void QGraphicsContext::doneCurrent()
+{
+    Q_ASSERT(m_gl);
     m_gl->doneCurrent();
 }
 
diff --git a/src/render/backend/qgraphicscontext_p.h b/src/render/backend/qgraphicscontext_p.h
index 37b55500f..6cae74612 100644
--- a/src/render/backend/qgraphicscontext_p.h
+++ b/src/render/backend/qgraphicscontext_p.h
@@ -104,6 +104,8 @@ public:
     void releaseOpenGL();
     void setOpenGLContext(QOpenGLContext* ctx, QSurface *surface);
     QOpenGLContext *openGLContext() { return m_gl; }
+    bool makeCurrent(QSurface *surface);
+    void doneCurrent();
 
     void activateShader(RenderShader* shader);
     QOpenGLShaderProgram *containsProgram(const ProgramDNA &dna) const
diff --git a/src/render/backend/renderer.cpp b/src/render/backend/renderer.cpp
index 3b4105488..1451253fe 100644
--- a/src/render/backend/renderer.cpp
+++ b/src/render/backend/renderer.cpp
@@ -331,7 +331,7 @@ void Renderer::initialize(QOpenGLContext *context)
     }
     m_graphicsContext->setOpenGLContext(ctx, m_surface);
 
-    if (enableDebugLogging) {
+    if (enableDebugLogging && ctx->makeCurrent(m_surface)) {
         bool supported = ctx->hasExtension("GL_KHR_debug");
         if (supported) {
             qCDebug(Backend) << "Qt3D: Enabling OpenGL debug logging";
@@ -350,6 +350,7 @@ void Renderer::initialize(QOpenGLContext *context)
         } else {
             qCDebug(Backend) << "Qt3D: OpenGL debug logging requested but GL_KHR_debug not supported";
         }
+        ctx->doneCurrent();
     }
 
     // Awake setScenegraphRoot in case it was waiting