From 60f22c51b94a5be0f3f9b8a9f71ff69fad09db97 Mon Sep 17 00:00:00 2001
From: Zach Pomerantz <zach@highfidelity.io>
Date: Thu, 17 Mar 2016 16:27:36 -0700
Subject: [PATCH] Check qml gl context on create

---
 libraries/gl/src/gl/OffscreenGLCanvas.cpp   | 18 ++++++++++++++----
 libraries/gl/src/gl/OffscreenGLCanvas.h     |  2 +-
 libraries/gl/src/gl/OffscreenQmlSurface.cpp |  8 ++++++--
 3 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/libraries/gl/src/gl/OffscreenGLCanvas.cpp b/libraries/gl/src/gl/OffscreenGLCanvas.cpp
index 6ce80296e9..1b10d6b032 100644
--- a/libraries/gl/src/gl/OffscreenGLCanvas.cpp
+++ b/libraries/gl/src/gl/OffscreenGLCanvas.cpp
@@ -32,17 +32,27 @@ OffscreenGLCanvas::~OffscreenGLCanvas() {
     _context->doneCurrent();
 }
 
-void OffscreenGLCanvas::create(QOpenGLContext* sharedContext) {
+bool OffscreenGLCanvas::create(QOpenGLContext* sharedContext) {
     if (nullptr != sharedContext) {
         sharedContext->doneCurrent();
         _context->setShareContext(sharedContext);
     }
     _context->setFormat(getDefaultOpenGLSurfaceFormat());
-    _context->create();
+    if (_context->create()) {
+        _offscreenSurface->setFormat(_context->format());
+        _offscreenSurface->create();
+        return true;
+    }
 
-    _offscreenSurface->setFormat(_context->format());
-    _offscreenSurface->create();
+    std::call_once(_reportOnce, []{
+        qWarning() << "GL Version: " << QString((const char*) glGetString(GL_VERSION));
+        qWarning() << "GL Shader Language Version: " << QString((const char*) glGetString(GL_SHADING_LANGUAGE_VERSION));
+        qWarning() << "GL Vendor: " << QString((const char*) glGetString(GL_VENDOR));
+        qWarning() << "GL Renderer: " << QString((const char*) glGetString(GL_RENDERER));
+        qWarning() << "Failed to create OffscreenGLCanvas";
+    });
 
+    return false;
 }
 
 bool OffscreenGLCanvas::makeCurrent() {
diff --git a/libraries/gl/src/gl/OffscreenGLCanvas.h b/libraries/gl/src/gl/OffscreenGLCanvas.h
index 0f02e7c76f..9858c7cefa 100644
--- a/libraries/gl/src/gl/OffscreenGLCanvas.h
+++ b/libraries/gl/src/gl/OffscreenGLCanvas.h
@@ -23,7 +23,7 @@ class OffscreenGLCanvas : public QObject {
 public:
     OffscreenGLCanvas();
     ~OffscreenGLCanvas();
-    void create(QOpenGLContext* sharedContext = nullptr);
+    bool create(QOpenGLContext* sharedContext = nullptr);
     bool makeCurrent();
     void doneCurrent();
     QOpenGLContext* getContext() {
diff --git a/libraries/gl/src/gl/OffscreenQmlSurface.cpp b/libraries/gl/src/gl/OffscreenQmlSurface.cpp
index 6a780d74e2..33287493d4 100644
--- a/libraries/gl/src/gl/OffscreenQmlSurface.cpp
+++ b/libraries/gl/src/gl/OffscreenQmlSurface.cpp
@@ -65,7 +65,11 @@ class OffscreenQmlRenderer : public OffscreenGLCanvas {
 public:
 
     OffscreenQmlRenderer(OffscreenQmlSurface* surface, QOpenGLContext* shareContext) : _surface(surface) {
-        OffscreenGLCanvas::create(shareContext);
+        if (!OffscreenGLCanvas::create(shareContext)) {
+            static const char* error = "Failed to create OffscreenGLCanvas";
+            qWarning() << error;
+            throw error;
+        };
 
         _renderControl = new QMyQuickRenderControl();
 
@@ -153,7 +157,7 @@ private:
             qWarning("Failed to make context current on render thread");
             return;
         }
-        _renderControl->initialize(_context);
+        _renderControl->initialize(getContext());
         setupFbo();
         _escrow.setRecycler([this](GLuint texture){
             _textures.recycleTexture(texture);