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QTimer in QQuickItem’s updatePaintNode()
user28 last edited by
From this blog, I understand that threaded renderer is used by default on mac.
Is it possible to start a timer in QQuickItem's updatePaintNode() on mac? During updatePaintNode, on mac we are currently on the scene graph renderer thread with the scene graph's OpenGL context current.
@QSGNode *AAA::updatePaintNode(QSGNode *oldNode, UpdatePaintNodeData *)
m_timer = new(std::nothrow) QTimer(0);
connect(m_timer, SIGNAL(timeout()), this, SLOT(pulse_()),Qt::DirectConnection);
// Draw stuff
I want the timer to be executed continuously and like to destroy it in my class's destructor.. I am not sure how the render thread's event loop works. With the above code, timeout events stop once drawing completes and then re-starts when update occurs the next time.
Basically , I am using a custom library for drawing an OpenGL component. At certain conditions, if the drawing and GUI threads are different, the library blocks the GUI thread and waits for a pulse event to unblock the UI thread.
I am trying to send this pulse event from a timer that is running in the renderer thread.
I am trying to figure out the best place to place my timer in multithreaded environment. Would appreciate any help on this.