LuminalVGD is NortheBridge Foundation's first-party virtual display driver for LuminalShine: a Rust UMDF IddCx driver that creates per-client virtual monitors with exact modes and HDR10, and hands finished frames to the streaming host through a shared-memory texture ring — no desktop-capture API in the hot path.
This is the first public release (alpha). It replaces SudoVDA as LuminalShine's virtual display backend; LuminalShine 26.08.0-beta.1 and newer bundle, install, and default to this driver.
Highlights
Display
- Per-client virtual monitors created and destroyed per streaming session, with identity retention — Windows remembers resolution, HDR state, and scaling for each client across reconnects.
- Exact modes: up to four modes per monitor at millihertz-precise refresh rates (59.94 Hz works), 320×200 through 7680×4320, no refresh ceiling. Frame-generation refresh doubling is a mode switch, not a monitor recreate.
- HDR10 end to end: CTA-861.3 EDID metadata, FP16 scRGB frame transport, 10-bit wire formats — Windows engages advanced color natively on the virtual display.
- Hardware cursor plane: the cursor is transported out-of-band (shape + position via a shared section) and composited by the host at encode time — cursor motion stays smooth even over an idle desktop.
Transport
- Direct-to-encoder frame ring: the driver GPU-copies each composed frame into named keyed-mutex shared textures; the host claims frames via a lock-free cross-process protocol (take-CAS hardened, race-tested with threaded regression suites and live soaks).
- Every wait is bounded. No IddCx callback performs D3D work inline, teardown shares a hard deadline budget, and a wedged worker can never hang the compositor, the control plane, or the machine — the reliability failure class this driver was built to eliminate.
Lifecycle & control
- Driver-side lease watchdog reaps orphaned monitors when a stream stops pinging.
- Permanent display pool: always-on virtual displays that survive reboots (up to 4).
- Locked-down control surface: creating, destroying, or leasing monitors requires SYSTEM or an elevated Administrator — unprivileged processes are refused at open.
Diagnostics
- ETW TraceLogging provider
NortheBridge.LuminalVGD{c501990d-df12-5581-60a8-f55d593d7f7c}with breadcrumbs across bring-up, transport, and cursor paths. vgd-probeCLI (build from source) exercises the full control + transport cycle, including a ring-soak mode with stall autopsy.
Requirements
- Windows 11 x64 (build 22000+). Windows 11 24H2 (build 26100+) is required for full HDR support; SDR works on any Windows 11.
- LuminalShine 26.08.0-beta.1 or newer to stream (the driver alone only provides virtual displays).
Install
Unpack the zip, then from an elevated PowerShell in the unpacked folder:
powershell -ExecutionPolicy Bypass -File .\install-driver.ps1 -Package .\driver-package -SeedTrustedPublisher-SeedTrustedPublisher places the NortheBridge signing certificate in LocalMachine\TrustedPublisher only (the certificate chains to a public root; the Root store is never touched) so the install runs without a prompt. Uninstall with uninstall-driver.ps1. Full details in the bundled INSTALL.md.
LuminalShine 26.08.0-beta.1+ installs this driver automatically — the manual install is only needed for standalone use or driver-only updates.
Integrity
luminal_vgd_driver.dllandluminalvgd.catare Authenticode-signed by NortheBridge Foundation and RFC-3161 timestamped.- Device Manager reports driver version 0.1.0.8 (this release, build 8).
- Verify the download against
SHA256SUMS.
Known limitations (alpha)
- Gamma-ramp requests (Night Light, calibration) are acknowledged but not applied to streamed pixels — identical behavior to streaming a physical display, where capture is also pre-LUT.
- AV1 4:4:4 encoding is an NVENC hardware gap on consumer GeForce GPUs, not a driver limitation.
- Signing is OV + TrustedPublisher; Microsoft attestation signing (no TrustedPublisher step) is planned.
Provenance & license
AGPL-3.0-only (commercial licensing available — see LICENSING.md). Rust core and transport lineage from pf-vdisplay (MIT/Apache-2.0); SudoVDA behaviors were reimplemented from specification, not ported code. See THIRD-PARTY-NOTICES.md.