Fix assert when using QScreenRayCaster with multiple viewports

The mouse can't be in all viewports at once so the ray will not be
valid for all the viewports.

Cherry-picked from b68ebfde583dc5cec7ae60f752f1e05371e57dba

Change-Id: Id196f043c4f670cd2106993fc5c0a9dd468a491e
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>

1 files changed, 5 insertions, 2 deletions

diff --git a/src/render/jobs/raycastingjob.cpp b/src/render/jobs/raycastingjob.cpp
index e76b9fe8d..7d3af34cc 100644
--- a/src/render/jobs/raycastingjob.cpp
+++ b/src/render/jobs/raycastingjob.cpp
@@ -164,8 +164,11 @@ bool RayCastingJob::runHelper()
             rays.back().transform(*pair.first->worldTransform());
             break;
         case QAbstractRayCasterPrivate::ScreenScapeRayCaster:
-            for (const PickingUtils::ViewportCameraAreaDetails &vca : vcaDetails)
-                rays << rayForViewportAndCamera(vca, nullptr, pair.second->position());
+            for (const PickingUtils::ViewportCameraAreaDetails &vca : vcaDetails) {
+                auto ray = rayForViewportAndCamera(vca, nullptr, pair.second->position());
+                if (ray.isValid())
+                    rays << ray;
+            }
             break;
         default:
             Q_UNREACHABLE();