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render-settings

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Writing render settings to control rendering behavior. Use when user asks to change render settings, set max bounces, configure path tracing, change render quality, or modify RTX settings on a RenderProduct.

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How to use this skill

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  1. Open your project in Codex.
  2. Copy and paste the prompt below.
  3. Review files and risks before approving any action.
Prompt to paste
Inspect the Agent Skill at https://github.com/NVIDIA-Omniverse/ovrtx/blob/HEAD/skills/render-settings/SKILL.md and all supporting files. Report provenance, permissions, scripts, dependencies, and security risks. Propose an exact installation into .agents/skills/render-settings, but wait for my approval before writing files or running scripts.

Copying this prompt does not install or run the skill. Review third-party files before use.

Render Settings

When to Use

Use this skill when the user asks to change render settings, set max bounces, configure path tracing, change render quality, or modify RTX settings on a RenderProduct.

Inputs

Resolve inputs in this order: existing repository files and referenced snippets, explicit user request, then broader agent context.

  • Target API surface: Python, C/C++, USD, or a combination.
  • RenderProduct prim path and the exact omni:rtx:* setting attribute to author or update.
  • Desired setting value, USD type, runtime/write timing, and whether reset/warmup behavior matters.
  • Existing scene or snippet that already owns related RenderProduct settings.
  • Repository source snippets referenced below. Treat these snippets as the API source of truth.

Prerequisites

  • Use an ovrtx checkout that contains the referenced examples and docs tests.
  • Read the relevant > **Source:** snippet before writing or explaining API usage.
  • Confirm the setting belongs on the RenderProduct prim, not on a Camera, RenderVar, or renderer creation option.
  • Use writing-attributes when the setting is changed through runtime APIs.

Instructions

  1. Identify the RenderProduct path and the exact RTX setting attribute to change.
  2. Write settings on the RenderProduct prim, not on the Camera or RenderVar prim.
  3. Match the value type to the USD attribute schema and preserve existing authored settings that are unrelated to the request.
  4. Apply the writing-attributes skill when setting values through runtime APIs rather than static USD.
  5. When changing code, run the render-settings docs test that owns the setting snippet whenever practical.

Output Format

  • For explanations, cite the relevant API names, source snippets, and caveats.
  • For code changes, summarize the files changed, snippets affected, and validation run.

Scripts

This skill has no scripts.

Limitations

  • The referenced snippets remain the source of truth; update or add tested snippets before documenting new API usage.

Overview

Render settings in ovrtx are written as attributes on the RenderProduct prim. To change a setting, use write_attribute() in Python or ovrtx_write_attribute() in C, targeting the RenderProduct prim path (e.g., /Render/Camera) with the setting's attribute name.

Settings use the omni:rtx: namespace prefix. For example, to set the maximum number of path tracing bounces, write omni:rtx:rtpt:maxBounces as an int32 attribute.

After changing a render setting, call reset() and run warm-up frames to allow the renderer to converge with the new setting.

Python

Set a render setting on a RenderProduct

Source: tests/docs/python/test_base.py snippet doc-set-render-setting

C

Set a render setting on a RenderProduct

Source: tests/docs/c/test_base.cpp snippet doc-set-render-setting-c

Key Types / Functions

PythonC
renderer.write_attribute(prim_paths=["/Render/Camera"], attribute_name="omni:rtx:rtpt:maxBounces", tensor=np.array([value], dtype=np.int32))ovrtx_write_attribute(renderer, &binding, &buffer, OVRTX_DATA_ACCESS_SYNC) with int32 DLTensor

Render Mode Selection

SettingTypeDefaultDescription
omni:rtx:rendermodestring"Real-Time Path-Tracing"Render mode: "Real-Time Path-Tracing", "PathTracing", or "Minimal"

Real-Time Path-Tracing Settings (rtpt:)

Sampling and Caching

SettingTypeDefault
omni:rtx:rtpt:cached:enabledbooltrue
omni:rtx:rtpt:lightcache:cached:enabledbooltrue
omni:rtx:rtpt:ris:meshLightsboolfalse

Ray Bounces and Shading

SettingTypeDefault
omni:rtx:rtpt:maxBouncesint3
omni:rtx:rtpt:maxSpecularAndTransmissionBouncesint3
omni:rtx:rtpt:maxVolumeBouncesint15
omni:rtx:pt:fractionalCutoutOpacitybooltrue
omni:rtx:rtpt:maxRoughnessfloat0.3
omni:rtx:rt:reflections:roughnessCacheThresholdfloat0.3
omni:rtx:rtpt:translucency:virtualMotion:enabledbooltrue

Firefly Filter

SettingTypeDefault
omni:rtx:rtpt:fireflyFilter:enabledbooltrue
omni:rtx:rtpt:fireflyFilter:maxUnexposedIntensityPerSamplefloat3200.0
omni:rtx:rtpt:fireflyFilter:maxUnexposedIntensityPerSampleDiffusefloat3200.0
omni:rtx:rtpt:fireflyFilter:maxPerEmissiveUnexposedIntensityfloat3200.0

Gaussian Splatting

SettingTypeDefault
omni:rtx:rtpt:gaussian:accumulatedDepth:enabledbooltrue
omni:rtx:rtpt:gaussian:accumulatedAlbedo:enabledbooltrue
omni:rtx:rtpt:gaussian:maxGaussiansToAccumulateint48

Path Tracing Settings (pt:)

Path Tracing

SettingTypeDefault
omni:rtx:pt:samplesPerPixelint512
omni:rtx:pt:samplesPerIterationint1
omni:rtx:pt:adaptiveSampling:enabledbooltrue
omni:rtx:pt:limits:maxBouncesint4
omni:rtx:pt:limits:maxGlossyBouncesint6
omni:rtx:pt:maxVolumeBouncesint15
omni:rtx:pt:limits:maxFogBouncesint2
omni:rtx:pt:fractionalCutoutOpacitybooltrue

Denoising

SettingTypeDefault
omni:rtx:pt:denoising:enabledbooltrue
omni:rtx:pt:denoising:optix:temporalboolfalse
omni:rtx:pt:denoising:blendFactorfloat0.0
omni:rtx:pt:denoising:optix:denoiseAOVsbooltrue

Sampling and Caching

SettingTypeDefault
omni:rtx:pt:radianceCache:enabledbooltrue
omni:rtx:pt:lightCache:enabledbooltrue
omni:rtx:pt:ris:meshLightsboolfalse
omni:rtx:pathtracing:rayguide:cached:enabledboolfalse

Firefly Filter

SettingTypeDefault
omni:rtx:pt:fireflyFilter:enabledbooltrue
omni:rtx:pt:fireflyFilter:maxUnexposedIntensityPerSamplefloat3200.0
omni:rtx:pt:fireflyFilter:maxUnexposedIntensityPerSampleDiffusefloat3200.0
omni:rtx:pt:fireflyFilter:maxPerEmissiveUnexposedIntensityfloat3200.0

Spectral Rendering

SettingTypeDefault
omni:rtx:pathtracing:spectral:enabledboolfalse
omni:rtx:pathtracing:spectral:wavelengthMinfloat10.0
omni:rtx:pathtracing:spectral:wavelengthMaxfloat10000.0
omni:rtx:renderingColorSpacestring"lin_rec709_scene"
omni:rtx:pathtracing:spectral:responseCurveuint0

Non-Uniform Volumes

SettingTypeDefault
omni:rtx:pt:ptvol:enabledboolfalse
omni:rtx:pt:volumes:transmittanceMethodintBiasedRayMarching
omni:rtx:pt:volumes:tracking:maxScatteringStepsint1024
omni:rtx:pt:volumes:tracking:maxShadowStepsint32
omni:rtx:pt:limits:maxVolumeBouncesint2

Multi-GPU

SettingTypeDefault
omni:rtx:pt:multigpu:enabledbooltrue
omni:rtx:pt:mgpu:autoLoadBalancing:enabledbooltrue
omni:rtx:pt:mgpu:compressRadianceboolfalse
omni:rtx:pt:mgpu:compressAlbedobooltrue
omni:rtx:pt:mgpu:compressNormalsbooltrue
omni:rtx:multiThreading:enabledbooltrue

Global Volumetric Effects

SettingTypeDefault
omni:rtx:pt:ptvol:raySkyboolfalse
omni:rtx:pt:ptvol:raySkyScalefloat1.0
omni:rtx:pt:ptvol:raySkyDomelightboolfalse

Anti-Aliasing

SettingTypeDefault
omni:rtx:pt:pixelFilter:filterintTriangle
omni:rtx:pt:pixelFilter:radiusfloat1.0

Minimal Settings

Minimal mode is optimized for speed-of-light rendering performance and stability. It only respects the first DistantLight found in the scene, and shadows from that light are hard shadows. Other light types, including DomeLight, are ignored for Minimal mode lighting; if no DistantLight exists, Minimal mode uses a single camera light instead. For improved visibility, use the ambient light attributes documented in docs/sensors/cameras/render_modes/minimal.rst, or disable shadows with omni:rtx:minimal:castShadows.

SettingTypeDescription
omni:rtx:minimal:modeintMinimal render mode variant
omni:rtx:minimal:constantColorfloat3Constant color output
omni:rtx:minimal:castShadowsboolEnable hard shadows from the first DistantLight
omni:rtx:rt:ambientLight:colorfloat3Ambient light color
omni:rtx:rt:ambientLight:intensityfloatAmbient light intensity

Troubleshooting

  • Render settings are attributes on the RenderProduct prim, not on a separate RenderSettings prim. Write them to the same prim path you pass to step() (e.g., /Render/Camera).
  • The dtype must match exactly -- omni:rtx:rtpt:maxBounces is int32, not int64.
  • After changing a setting, call reset() and run warm-up frames before capturing output. The renderer needs time to reconverge.
  • Settings use the omni:rtx: namespace prefix, with subsystem prefixes like rtpt: (real-time path tracing), post: (post-processing), etc.

References

  • Use the > **Source:** directives in this skill to locate tested snippets before reusing API patterns.
  • Keep related skills, docs, and snippets synchronized when changing the workflow.