# Ovrtx Materialx Openpbr

> Prepare Blender materials for the add-on's OVRTX MaterialX/OpenPBR conversion and diagnose failures without renderer source access. Use for source textures, OpenPBR graphs, black/red/flat OVRTX materials, missing bindings, UV/normal-map issues, or Blender-versus-OVRTX material comparisons.

- Skill: `nvidia-omniverse/ovrtx-materialx-openpbr` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add nvidia-omniverse/ovrtx-materialx-openpbr`
- Raw SKILL.md: https://api.skillmd.com/api/skills/nvidia-omniverse/ovrtx-materialx-openpbr/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- License: Apache-2.0
- Author: NVIDIA-Omniverse (https://skillmd.com/u/nvidia-omniverse)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/nvidia-omniverse/ovrtx-materialx-openpbr

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# OVRTX MaterialX/OpenPBR

Prepare Blender materials for the add-on's OVRTX MaterialX/OpenPBR conversion
and diagnose failures through documented add-on and runtime interfaces.

## When to Use

Use for source textures, OpenPBR graphs, black/red/flat OVRTX materials, missing bindings, UV/normal-map issues, or Blender-versus-OVRTX material comparisons.

## Boundary and inputs

- Work through the installed add-on, Blender APIs, documented probes, and the
  supported runtime interfaces.
- Preserve source textures and relative paths. Do not bake a comparison image
  and call it a material conversion.
- Record Blender, add-on, runtime, material, texture, UV, and color-space
  identities before changing the graph.

## Instructions

1. Inventory only materials assigned to renderable polygons and verify evaluated
   geometry, slots, polygon assignment, UV layer, and texture paths.
2. Build or repair a reachable graph from the active material output. Prefer
   named Principled/OpenPBR-adjacent inputs and source image textures over
   disconnected diagnostic nodes.
3. Validate base color, roughness, metallic/specular, normal, transmission,
   opacity, emission, coat, sheen, and texture color-space intent separately.
4. Confirm the add-on's generated MaterialX/OpenPBR binding and geomprop/UV name
   in the resolved output. Treat USD Preview fallback as a separate lane.
5. Render a neutral control and one material-specific fixture through Blender and
   OVRTX. Compare scene-linear/HDR data when available; use display PNGs only as
   a separately labeled presentation comparison.
6. Classify each used material as `faithful`, `approximate`, `unbound`, or
   `runtime-unavailable`, with the cause and next action.

## Failure ladder

Diagnose in this order: runtime/readback, stage/material identity and binding,
UV/texture path and color space, global lighting/exposure/display transform,
then individual lobe conversion. Do not change albedo to hide a light or
tone-map problem. Do not reject a scene because an unreachable unsupported node
exists.

## Handoff

Summarize the material changed, conversion class, native result, and any
unsupported node or texture. Add hashes, mapping tables, fixture renders, or
raw/display comparisons only when the caller needs a reproducible handoff or
review artifact. Pair with `ovrtx-render-settings` for probed scene
controls and a contributor parity skill for graph-family regression tests.