RenderSettings: only destroy the RenderSettings component that is used

Since we only create a backend node for the first RenderSettings component that
is inserted in the scene, we should only destroy that instance. Otherwise, in
the case we have several QRenderSettings components in a scene, if one of them
gets destroyed we might end up destroying the RenderSettings instanced actually
used by the Renderer.

We so far assumed there would only be a single QRenderSettings per application
but introducing Scene3DView might change that.

Change-Id: Ibef1328253b871f3b40a2298ccd8504130d75d86
Reviewed-by: Mike Krus <mike.krus@kdab.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/src/render/backend/rendersettings.cpp b/src/render/backend/rendersettings.cpp
index 96c90f20d..2b8067ce8 100644
--- a/src/render/backend/rendersettings.cpp
+++ b/src/render/backend/rendersettings.cpp
@@ -131,8 +131,10 @@ void RenderSettingsFunctor::destroy(Qt3DCore::QNodeId id) const
     Q_UNUSED(id);
     // Deletes the old settings object
     auto settings = m_renderer->settings();
-    delete settings;
-    m_renderer->setSettings(nullptr);
+    if (settings && settings->peerId() == id) {
+        m_renderer->setSettings(nullptr);
+        delete settings;
+    }
 }
 
 } // namespace Render