[WSL] Qt `WId` and VSG XCB Native Window Handle Type Mismatch

[lonelyong]

Bug Description

When embedding a VSG renderer into a Qt window on Linux/WSL, the native window handle obtained from QWindow::winId() was passed directly to VSG as the XCB native window handle.

For example:

traits->nativeWindow = window->winId();

This causes a runtime type mismatch because QWindow::winId() returns Qt's WId type, while the VSG XCB backend expects an xcb_window_t.

Consider using std::uintptr_t instead of std::any here, since nativeWindow represents a native window handle.

[robertosfield]

Which Qt version? Which level linux distro? Which VSG and vsgQt version? Does it happen with vsgqtviewer example?

…

On Thu, 3 Sept 2026, 02:52 Yong Zhou, ***@***.***> wrote: *lonelyong* created an issue (vsg-dev/VulkanSceneGraph#1742) <#1742> Bug Description When embedding a VSG renderer into a Qt window on Linux/WSL, the native window handle obtained from QWindow::winId() was passed directly to VSG as the XCB native window handle. For example: traits->nativeWindow = window->winId(); This causes a runtime type mismatch because QWindow::winId() returns Qt's WId type, while the VSG XCB backend expects an xcb_window_t. Image: Image (view on web) <https://github.com/user-attachments/assets/3375fa4f-2a53-4a42-a353-d596fefc4e0d> — Reply to this email directly, view it on GitHub <#1742?email_source=notifications&email_token=AAKEGUD46XQJLWULHDA3XTT5NDFFJA5CNFSL4Z3JMQ5C6L3HNF2C22DVMIXUS43TOVSS6NJTGMYTEMRTGY4DNJTSMVQXG33OVJZXKYTTMNZGSYTFMSSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAKEGUCEUCQ3OJXV2YXKWG35NDFFJAVCNFSNUABFKJSXA33TNF2G64TZHMYTIOBWGA4TAMBUHNEXG43VMU5TKMZTGEZDEMZWHA3KC5QC> . Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/AAKEGUAVSJP4FR7COLEIC7D5NDFFJA5CNFSL4Z3JMQ5C6L3HNF2C22DVMIXUS43TOVSS6NJTGMYTEMRTGY4DNJTSMVQXG33OVJZXKYTTMNZGSYTFMSSWK5TFNZ2KUZTPN52GK4S7NFXXG> and Android <https://github.com/notifications/mobile/android/AAKEGUDYDQWXR65G74FNSOD5NDFFJA5CNFSL4Z3JMQ5C6L3HNF2C22DVMIXUS43TOVSS6NJTGMYTEMRTGY4DNJTSMVQXG33OVJZXKYTTMNZGSYTFMSSWK5TFNZ2K4ZTPN52GK4S7MFXGI4TPNFSA>. Download it today! You are receiving this because you are subscribed to this thread.Message ID: ***@***.***>

[lonelyong]

Reproduced on WSL / Ubuntu 24.04 / Qt 6.4 / X11 (XCB). The issue is a WId vs xcb_window_t type mismatch. Since nativeWindow uses std::any, passing window-&gt;winId() directly is easy to misuse and results in std::bad_any_cast. The workaround is: traits-&gt;nativeWindow = &nbsp; &nbsp; static_cast(window-&gt;winId()); This suggests the nativeWindow API may be error-prone, as the correct native handle type is not enforced at compile time. Original&nbsp;

…

------------------ From: Robert Osfield ***@***.***&gt; Date: Thu,Sep 3,2026 2:59 PM To: vsg-dev/VulkanSceneGraph ***@***.***&gt; Cc: Yong Zhou ***@***.***&gt;, Author ***@***.***&gt; Subject: Re: [vsg-dev/VulkanSceneGraph] [WSL] Qt `WId` and VSG XCB Native Window Handle Type Mismatch (Issue #1742) robertosfield left a comment (vsg-dev/VulkanSceneGraph#1742) Which Qt version? Which level linux distro? Which VSG and vsgQt version? Does it happen with vsgqtviewer example? On Thu, 3 Sept 2026, 02:52 Yong Zhou, ***@***.***&gt; wrote: &gt; *lonelyong* created an issue (vsg-dev/VulkanSceneGraph#1742) &gt; <#1742&gt; &gt; Bug Description &gt; &gt; When embedding a VSG renderer into a Qt window on Linux/WSL, the native &gt; window handle obtained from QWindow::winId() was passed directly to VSG &gt; as the XCB native window handle. &gt; &gt; For example: &gt; &gt; traits-&gt;nativeWindow = window-&gt;winId(); &gt; &gt; This causes a runtime type mismatch because QWindow::winId() returns Qt's &gt; WId type, while the VSG XCB backend expects an xcb_window_t. &gt; Image: Image (view on web) &gt; <https://github.com/user-attachments/assets/3375fa4f-2a53-4a42-a353-d596fefc4e0d&gt; &gt; &gt; — &gt; Reply to this email directly, view it on GitHub &gt; <#1742?email_source=notifications&amp;email_token=AAKEGUD46XQJLWULHDA3XTT5NDFFJA5CNFSL4Z3JMQ5C6L3HNF2C22DVMIXUS43TOVSS6NJTGMYTEMRTGY4DNJTSMVQXG33OVJZXKYTTMNZGSYTFMSSWK5TFNZ2KYZTPN52GK4S7MNWGSY3L&gt;, &gt; or unsubscribe &gt; <https://github.com/notifications/unsubscribe-auth/AAKEGUCEUCQ3OJXV2YXKWG35NDFFJAVCNFSNUABFKJSXA33TNF2G64TZHMYTIOBWGA4TAMBUHNEXG43VMU5TKMZTGEZDEMZWHA3KC5QC&gt; &gt; . &gt; Triage notifications, keep track of coding agent tasks and review pull &gt; requests on the go with GitHub Mobile for iOS &gt; <https://github.com/notifications/mobile/ios/AAKEGUAVSJP4FR7COLEIC7D5NDFFJA5CNFSL4Z3JMQ5C6L3HNF2C22DVMIXUS43TOVSS6NJTGMYTEMRTGY4DNJTSMVQXG33OVJZXKYTTMNZGSYTFMSSWK5TFNZ2KUZTPN52GK4S7NFXXG&gt; &gt; and Android &gt; <https://github.com/notifications/mobile/android/AAKEGUDYDQWXR65G74FNSOD5NDFFJA5CNFSL4Z3JMQ5C6L3HNF2C22DVMIXUS43TOVSS6NJTGMYTEMRTGY4DNJTSMVQXG33OVJZXKYTTMNZGSYTFMSSWK5TFNZ2K4ZTPN52GK4S7MFXGI4TPNFSA&gt;. &gt; Download it today! &gt; You are receiving this because you are subscribed to this thread.Message &gt; ID: ***@***.***&gt; &gt; — Reply to this email directly, view it on GitHub, or unsubscribe. Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS and Android. Download it today! You are receiving this because you authored the thread.Message ID: ***@***.***&gt;