UXCore.dll

Source	src/UXCore/ (14 files)
CMake target	UXCore
Type	Win32 DLL
Family	DirectUI engine layer

At a glance

The reconstructed DirectUI core: the element system Movie Maker's UI is built on. DirectUI ("DUI") is the markup-driven UI framework Microsoft used across Windows Live applications — elements, not Win32 controls, with behaviors attached via class names.

The original shipped as the system uxcore.dll (not present on modern Windows); this target reconstructs the subset the application depends on, in the DirectUI namespace.

Public surface

Exported via __declspec(dllexport) on the classes (no .def file):

Header	Contents
Element.h	The base Element class — the DUI element tree node
Containers.h	HWNDElement (root HWND hosting) and container elements
Controls.h	Native-feeling DUI controls
Resources.cpp	Resource/registry helpers (__cdecl — one of the two documented non-__stdcall exception families; see Calling Conventions)

Implementation notes

• HWNDElement owns the root HWND and key-focus tracking — the bridge between Win32 messages and the DUI element tree.
• A CRMDUIParser (referenced from Containers.h) parses DUI markup resources into the element tree.
• DirectUI .duxt resource loading is a known partial area — tracked as a top priority in the TODO audit.
• MovieMakerCore's UI layer consumes this core; the external surface it does not need is stubbed in src/MovieMakerCore/External/ (see Support Subsystems).

Testing

• Contracts in tests/mmr-python cover the exported entry points and decoration parity.
• tests/OtherDlls/ includes UXCore-adjacent checks.

Analysis artifacts

analysis/SharedMFDlls/, analysis/Shared/, and the UXCore sections of analysis/CrossDllImports/.