Proposal: DisplayXR for Adobe Substance 3D Designer (live material in 3D in Designer's own dock panel, Leia SR tested)

[joehillthunder]

Substance 3D Designer has no OpenXR mode. Its Python API reaches the Qt main window, dock panels and the computed graph outputs (SDTexture pixel buffers), but has no camera and no 3D-view render hook. So the prototype draws the 3D with a small material view of its own, fed live with Designer's outputs, and shows it inside Designer's UI.

Code: private repo @ ba91a40 (Apache-2.0 + NOTICE), access on request.

What it does

• A "DisplayXR 3D" dock added by a Designer plug-in. It runs on the app-neutral host core shared with MotionBuilder (Proposal: DisplayXR for Autodesk MotionBuilder (in its own viewer via the texture target; an in-process adapter on an app-neutral host core) #2423), Nuke (Proposal: DisplayXR for Foundry Nuke (3D in Nuke's own Viewer via the texture target; NDK node on the shared host core, Leia SR tested) #2433) and Houdini (Proposal: DisplayXR for SideFX Houdini (HDK adapter on the shared host core, dedicated 3D window; Leia SR tested) #2432), with two additions for hosts that have no draw hook:
  • dxrh_set_renderer: the host renders the eyes on the core's 3D thread;
  • dxrh_present_into: the core presents the v9 texture-target weave into a native child widget the host lays out. That's a DXGI flip swapchain, whose vsync also paces the session (xrWaitFrame doesn't pace a session that submits no layers (about 8,700 frames/s before the first image) #2386).
• The material view (D3D11):
  • the height output is real displaced geometry (a 512² grid), since a normal map alone gives no stereo depth;
  • GGX lighting with a shadowed key light, a sky/ground ambient and a soft backdrop, never black.
• Camera: it orbits the material, with the glass on the orbit centre and a canvas-true rig (XrCameraRigDXR: with an app-framed verticalFov wider than canvas-true, the eyes land far above the app camera and the frustum is entirely below the horizon #2422). The depth control fills the comfort budget for the material in view; going above it needs an explicit opt-in. The shared depth slider is honoured.
• Input: mouse orbit, pan and zoom in the dock. An XInput pad works only while Designer is in front, and the launcher turns off the runtime's own pad camera.
• Omniverse:
  • "Send to Omniverse (USD)" exports the outputs as a USD material on relief geometry: Kit layout, Y-up, cm, defaultPrim, UsdPreviewSurface + OmniPBR.
  • "Live to Omniverse" republishes every edit behind a shared live USD stage that USD Composer follows and shows in 3D. The Sampler prototype uses the same stage.

Measured

Designer 16.0.7, runtime v2.55.0, Leia SR laptop panel.

• 3D active in the dock at about 60 fps on Designer's own shipped gravel material, with Designer's menus and other apps fully usable alongside. Anchor fallback, because LeiaSR is 1.38.
• Parallax −0.10 % in front and +0.05 % behind (of panel width), inside the comfort budget. A seated viewer judged it comfortable.

What Designer would need to add

A 3D-view render hook in the Python or C++ API. Either:

• set or read the 3D view's camera and render it per eye into a texture; or
• accept a DisplayXR texture target for the 3D view.

Glasses-free 3D would then use Designer's own renderer, environment and camera inside its own 3D view, like the in-viewport prototypes for Blender, USD Composer, 3D Slicer and ParaView. Until then the eyes come from our material view.

Pending

• The mouse and Full-panel hands-on check.
• "Live to Omniverse" seen in USD Composer in 3D.
• macOS is blocked (no display plug-in); Linux is n/a.
• In anchor fallback, the woven texture looked un-interlaced in a dump. Retest with LeiaSR ≥ 1.39 (windowless).

🤖 Generated with Claude Code

[joehillthunder]

Readiness and seated check on the released runtime: Pass (2026-10-28)

Installed runtime v2.57.1 (C:\Program Files\DisplayXR) with the Leia SR plug-in 2.19.1, not sim-display, started from the default launcher.

Check	Result	Conditions
Launch, "3D active" in Designer's own dock	Pass	~60 fps
Mouse orbit and reset	Pass	—
Full panel and back	Pass	opens at 3840×2400, returns to the dock
Depth control	Pass	0 % = no parallax; 100 % = front −0.10 % / behind +0.07 % of panel width (within the 0.14 % / 0.42 % budget); Reset restores 100 %
Seated check at the tested display (Leia SR)	Pass	100 % depth
Clean exit	Pass	two xrEndFrame −1 results only when the app window closes; matches #2349 and is harmless

Still open, not blocking: Live to Omniverse shown in Kit RTX in 3D (it passes headless), and a windowless retest once LeiaSR ≥ 1.39 is available.