Check context before attempting to release opengl resources

In case of QMl ApplicationWindow using applications, openGL context
seems to be 0 when the renderer gets destroyed at application
shutdown. Work around this by checking for context validity on
destructors before attempting to free openGL resources.

Change-Id: I5ba5209740f8f4467f4ba2cc8dd195171bcd13c8
Reviewed-by: Mika Salmela <mika.salmela@digia.com>

6 files changed, 34 insertions, 25 deletions

diff --git a/src/datavisualization/engine/bars3drenderer.cpp b/src/datavisualization/engine/bars3drenderer.cpp
index ecdac21f..f13b6e79 100644
--- a/src/datavisualization/engine/bars3drenderer.cpp
+++ b/src/datavisualization/engine/bars3drenderer.cpp
@@ -99,11 +99,13 @@ Bars3DRenderer::Bars3DRenderer(Bars3DController *controller)
 
 Bars3DRenderer::~Bars3DRenderer()
 {
-    m_textureHelper->glDeleteFramebuffers(1, &m_selectionFrameBuffer);
-    m_textureHelper->glDeleteRenderbuffers(1, &m_selectionDepthBuffer);
-    m_textureHelper->deleteTexture(&m_selectionTexture);
-    m_textureHelper->glDeleteFramebuffers(1, &m_depthFrameBuffer);
-    m_textureHelper->deleteTexture(&m_bgrTexture);
+    if (QOpenGLContext::currentContext()) {
+        m_textureHelper->glDeleteFramebuffers(1, &m_selectionFrameBuffer);
+        m_textureHelper->glDeleteRenderbuffers(1, &m_selectionDepthBuffer);
+        m_textureHelper->deleteTexture(&m_selectionTexture);
+        m_textureHelper->glDeleteFramebuffers(1, &m_depthFrameBuffer);
+        m_textureHelper->deleteTexture(&m_bgrTexture);
+    }
 
     delete m_barShader;
     delete m_barGradientShader;
diff --git a/src/datavisualization/engine/drawer.cpp b/src/datavisualization/engine/drawer.cpp
index 14f0b315..f78b2d29 100644
--- a/src/datavisualization/engine/drawer.cpp
+++ b/src/datavisualization/engine/drawer.cpp
@@ -56,7 +56,8 @@ Drawer::Drawer(Q3DTheme *theme)
 Drawer::~Drawer()
 {
     delete m_textureHelper;
-    glDeleteBuffers(1, &m_pointbuffer);
+    if (QOpenGLContext::currentContext())
+        glDeleteBuffers(1, &m_pointbuffer);
 }
 
 void Drawer::initializeOpenGL()
diff --git a/src/datavisualization/engine/scatter3drenderer.cpp b/src/datavisualization/engine/scatter3drenderer.cpp
index 00452cf7..ee5c119e 100644
--- a/src/datavisualization/engine/scatter3drenderer.cpp
+++ b/src/datavisualization/engine/scatter3drenderer.cpp
@@ -98,11 +98,13 @@ Scatter3DRenderer::Scatter3DRenderer(Scatter3DController *controller)
 
 Scatter3DRenderer::~Scatter3DRenderer()
 {
-    m_textureHelper->glDeleteFramebuffers(1, &m_selectionFrameBuffer);
-    m_textureHelper->glDeleteRenderbuffers(1, &m_selectionDepthBuffer);
-    m_textureHelper->deleteTexture(&m_selectionTexture);
-    m_textureHelper->glDeleteFramebuffers(1, &m_depthFrameBuffer);
-    m_textureHelper->deleteTexture(&m_bgrTexture);
+    if (QOpenGLContext::currentContext()) {
+        m_textureHelper->glDeleteFramebuffers(1, &m_selectionFrameBuffer);
+        m_textureHelper->glDeleteRenderbuffers(1, &m_selectionDepthBuffer);
+        m_textureHelper->deleteTexture(&m_selectionTexture);
+        m_textureHelper->glDeleteFramebuffers(1, &m_depthFrameBuffer);
+        m_textureHelper->deleteTexture(&m_bgrTexture);
+    }
     delete m_dotShader;
     delete m_dotGradientShader;
     delete m_depthShader;
diff --git a/src/datavisualization/engine/surface3drenderer.cpp b/src/datavisualization/engine/surface3drenderer.cpp
index 69acb6b2..912edd97 100644
--- a/src/datavisualization/engine/surface3drenderer.cpp
+++ b/src/datavisualization/engine/surface3drenderer.cpp
@@ -134,16 +134,17 @@ Surface3DRenderer::Surface3DRenderer(Surface3DController *controller)
 
 Surface3DRenderer::~Surface3DRenderer()
 {
-    m_textureHelper->glDeleteFramebuffers(1, &m_depthFrameBuffer);
-    m_textureHelper->glDeleteRenderbuffers(1, &m_selectionDepthBuffer);
-    m_textureHelper->glDeleteFramebuffers(1, &m_selectionFrameBuffer);
-
-    m_textureHelper->deleteTexture(&m_depthTexture);
-    m_textureHelper->deleteTexture(&m_depthModelTexture);
-    m_textureHelper->deleteTexture(&m_selectionTexture);
-    m_textureHelper->deleteTexture(&m_selectionResultTexture);
-    m_textureHelper->deleteTexture(&m_uniformGradientTexture);
+    if (QOpenGLContext::currentContext()) {
+        m_textureHelper->glDeleteFramebuffers(1, &m_depthFrameBuffer);
+        m_textureHelper->glDeleteRenderbuffers(1, &m_selectionDepthBuffer);
+        m_textureHelper->glDeleteFramebuffers(1, &m_selectionFrameBuffer);
 
+        m_textureHelper->deleteTexture(&m_depthTexture);
+        m_textureHelper->deleteTexture(&m_depthModelTexture);
+        m_textureHelper->deleteTexture(&m_selectionTexture);
+        m_textureHelper->deleteTexture(&m_selectionResultTexture);
+        m_textureHelper->deleteTexture(&m_uniformGradientTexture);
+    }
     delete m_shader;
     delete m_depthShader;
     delete m_backgroundShader;
diff --git a/src/datavisualization/utils/abstractobjecthelper.cpp b/src/datavisualization/utils/abstractobjecthelper.cpp
index d47f2fe6..96cdc0c4 100644
--- a/src/datavisualization/utils/abstractobjecthelper.cpp
+++ b/src/datavisualization/utils/abstractobjecthelper.cpp
@@ -34,10 +34,12 @@ AbstractObjectHelper::AbstractObjectHelper()
 
 AbstractObjectHelper::~AbstractObjectHelper()
 {
-    glDeleteBuffers(1, &m_vertexbuffer);
-    glDeleteBuffers(1, &m_uvbuffer);
-    glDeleteBuffers(1, &m_normalbuffer);
-    glDeleteBuffers(1, &m_elementbuffer);
+    if (QOpenGLContext::currentContext()) {
+        glDeleteBuffers(1, &m_vertexbuffer);
+        glDeleteBuffers(1, &m_uvbuffer);
+        glDeleteBuffers(1, &m_normalbuffer);
+        glDeleteBuffers(1, &m_elementbuffer);
+    }
 }
 
 GLuint AbstractObjectHelper::vertexBuf()
diff --git a/src/datavisualization/utils/surfaceobject.cpp b/src/datavisualization/utils/surfaceobject.cpp
index 605376e2..6e4765e5 100644
--- a/src/datavisualization/utils/surfaceobject.cpp
+++ b/src/datavisualization/utils/surfaceobject.cpp
@@ -39,7 +39,8 @@ SurfaceObject::SurfaceObject()
 
 SurfaceObject::~SurfaceObject()
 {
-    glDeleteBuffers(1, &m_gridElementbuffer);
+    if (QOpenGLContext::currentContext())
+        glDeleteBuffers(1, &m_gridElementbuffer);
 }
 
 void SurfaceObject::setUpSmoothData(const QSurfaceDataArray &dataArray, const QRect &space,