Proceed to the next frame even if we cannot lock the surface

Previously, if the render surface could not be locked or makeCurrent
failed, the aspect thread would be stuck waiting for the next frame and
the render thread would be stuck waiting for the render jobs.

This change makes sure both threads continue, which will allow changes
to the surface to be synchronized and make the render thread try to
lock the surface again.

Task-number: QTBUG-66243
Change-Id: I01bbe4c2ca74961f363efbe87c0586edaad41c62
Reviewed-by: Harald Vistnes <harald.vistnes@gmail.com>
Reviewed-by: Sean Harmer <sean.harmer@kdab.com>
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

1 files changed, 5 insertions, 0 deletions

diff --git a/src/render/backend/renderer.cpp b/src/render/backend/renderer.cpp
index 8fa68191d..0b975a3d3 100644
--- a/src/render/backend/renderer.cpp
+++ b/src/render/backend/renderer.cpp
@@ -621,6 +621,11 @@ void Renderer::lockSurfaceAndRender()
     if (!createSurfaceLockAndMakeCurrent()) {
         m_surfaceLockers.clear();
         abortRenderJobs();
+        // We cannot render because we could not lock the surface or the surface is a nullptr.
+        // However, the surface might change in the next frontend/backend sync.
+        // We therefore need to make sure the aspect thread does not get stuck waiting for
+        // the next frame.
+        m_vsyncFrameAdvanceService->proceedToNextFrame();
         return;
     }
     // Let the aspect thread know that we promise to render