render-settings

name	render-settings
description	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.
license	LicenseRef-NvidiaProprietary
version	0.3.0
author	NVIDIA ovrtx
tags	["ovrtx","rendering","settings"]
tools	["Read","Grep"]

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 a uint32 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

Python	C
renderer.write_attribute(prim_paths=["/Render/Camera"], attribute_name="omni:rtx:rtpt:maxBounces", tensor=np.array([value], dtype=np.uint32))	ovrtx_write_attribute(renderer, &binding, &buffer, OVRTX_DATA_ACCESS_SYNC) with uint32 DLTensor

Render Mode Selection

Setting	Type	Default	Description
omni:rtx:rendermode	token	"RealTimePathTracing"	Render mode: "RealTimePathTracing", "PathTracing", or "Minimal"

Real-Time Path-Tracing Settings (rtpt:)

Sampling and Caching

Setting	Type	Default
omni:rtx:rtpt:cached:enabled	bool	true
omni:rtx:rtpt:lightcache:cached:enabled	bool	true
omni:rtx:rtpt:ris:meshLights	bool	false

Ray Bounces and Shading

Setting	Type	Default
omni:rtx:rtpt:maxBounces	uint	3
omni:rtx:rtpt:maxSpecularAndTransmissionBounces	uint	3
omni:rtx:rtpt:maxVolumeBounces	uint	3
omni:rtx:pt:fractionalCutoutOpacity	bool	true
omni:rtx:rtpt:maxRoughness	float	0.3
omni:rtx:rt:reflections:roughnessCacheThreshold	float	0.3
omni:rtx:rtpt:translucency:virtualMotion:enabled	bool	true

Firefly Filter

Setting	Type	Default
omni:rtx:rtpt:fireflyFilter:enabled	bool	true
omni:rtx:rtpt:fireflyFilter:maxUnexposedIntensityPerSample	float	3200.0
omni:rtx:rtpt:fireflyFilter:maxUnexposedIntensityPerSampleDiffuse	float	3200.0
omni:rtx:rtpt:fireflyFilter:maxPerEmissiveUnexposedIntensity	float	3200.0

Gaussian Splatting

Setting	Type	Default
omni:rtx:rtpt:gaussian:accumulatedDepth:enabled	bool	true
omni:rtx:rtpt:gaussian:accumulatedAlbedo:enabled	bool	true
omni:rtx:rtpt:gaussian:maxGaussiansToAccumulate	int	48

Path Tracing Settings (pt:)

Path Tracing

Setting	Type	Default
omni:rtx:pt:samplesPerPixel	uint	512
omni:rtx:pt:samplesPerIteration	int	1
omni:rtx:pt:adaptiveSampling:enabled	bool	true
omni:rtx:pt:limits:maxBounces	uint	4
omni:rtx:pt:limits:maxGlossyBounces	uint	6
omni:rtx:pt:maxVolumeBounces	uint	15
omni:rtx:pt:limits:maxFogBounces	uint	2
omni:rtx:pt:fractionalCutoutOpacity	bool	true

Denoising

Setting	Type	Default
omni:rtx:pt:denoising:enabled	bool	true
omni:rtx:pt:denoising:optix:temporal	bool	false
omni:rtx:pt:denoising:blendFactor	float	0.0
omni:rtx:pt:denoising:optix:denoiseAOVs	bool	true

Sampling and Caching

Setting	Type	Default
omni:rtx:pt:radianceCache:enabled	bool	true
omni:rtx:pt:lightCache:enabled	bool	true
omni:rtx:pt:ris:meshLights	bool	false
omni:rtx:pathtracing:rayguide:cached:enabled	bool	false

Firefly Filter

Setting	Type	Default
omni:rtx:pt:fireflyFilter:enabled	bool	true
omni:rtx:pt:fireflyFilter:maxUnexposedIntensityPerSample	float	3200.0
omni:rtx:pt:fireflyFilter:maxUnexposedIntensityPerSampleDiffuse	float	3200.0
omni:rtx:pt:fireflyFilter:maxPerEmissiveUnexposedIntensity	float	3200.0

Spectral Rendering

Setting	Type	Default
omni:rtx:pathtracing:spectral:enabled	bool	false
omni:rtx:pathtracing:spectral:wavelengthMin	float	10.0
omni:rtx:pathtracing:spectral:wavelengthMax	float	10000.0
omni:rtx:renderingColorSpace	string	"lin_rec709_scene"
omni:rtx:pathtracing:spectral:responseCurve	uint	0

Non-Uniform Volumes

Setting	Type	Default
omni:rtx:pt:ptvol:enabled	bool	false
omni:rtx:pt:volumes:transmittanceMethod	token	"biasedRayMarching"
omni:rtx:pt:volumes:tracking:maxScatteringSteps	int	1024
omni:rtx:pt:volumes:tracking:maxShadowSteps	int	32
omni:rtx:pt:limits:maxVolumeBounces	uint	2

Multi-GPU

Setting	Type	Default
omni:rtx:pt:multigpu:enabled	bool	true
omni:rtx:pt:mgpu:autoLoadBalancing:enabled	bool	true
omni:rtx:pt:mgpu:compressRadiance	bool	false
omni:rtx:pt:mgpu:compressAlbedo	bool	true
omni:rtx:pt:mgpu:compressNormals	bool	true
omni:rtx:multiThreading:enabled	bool	true

Global Volumetric Effects

Setting	Type	Default
omni:rtx:pt:ptvol:raySky	bool	false
omni:rtx:pt:ptvol:raySkyScale	float	1.0
omni:rtx:pt:ptvol:raySkyDomelight	bool	false

Anti-Aliasing

Setting	Type	Default
omni:rtx:pt:pixelFilter:filter	token	"triangle"
omni:rtx:pt:pixelFilter:radius	float	1.0

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.

Setting	Type	Description
omni:rtx:minimal:mode	int	Minimal render mode variant
omni:rtx:minimal:constantColor	color3f	Constant color output
omni:rtx:minimal:castShadows	bool	Enable hard shadows from the first DistantLight
omni:rtx:rt:ambientLight:color	color3f	Ambient light color
omni:rtx:rt:ambientLight:intensity	float	Ambient 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 the schema type exactly. Most integer settings above are uint, so write np.uint32 -- omni:rtx:rtpt:maxBounces is uint32, not int32 or int64. Settings typed token (such as omni:rtx:rendermode and omni:rtx:pt:pixelFilter:filter) are written as interned token IDs, not integers; see writing-attributes for the full USD-type-to-dtype table.
• 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.