The Gaussian Splat shape renders point-based scene representations composed of millions of oriented volumetric splats instead of traditional polygonal geometry. Gaussian splats are commonly generated from photogrammetry, neural rendering, or radiance field reconstruction workflows and provide an efficient way to represent highly detailed real-world captures.

Each splat is represented as an anisotropic 3D Gaussian distribution defined by:

• Position — center of the splat in 3D space
• Scale — ellipsoid size along each axis
• Orientation — rotation of the ellipsoid
• Color / Radiance — emitted or reflected appearance
• Opacity — transparency contribution

During rendering, Arnold projects and blends splats together to reconstruct continuous surfaces and volumetric detail with smooth transitions and high visual fidelity.

The Gaussian Splat shape loads and renders Gaussian splat datasets inside Arnold. These parameters control file loading, viewport display, color handling, and advanced rendering options.

Path

Specifies the Gaussian Splat file to load (PLY).

Up Axis

Specifies the coordinate-system convention used by the source splat file (for example, Y up or Z up). Set this to match how the splat dataset was authored so that the data is oriented correctly in the scene.

Min Pixel Width

Defines the minimum on-screen size of individual splats in pixels. Increasing the Min Pixel Width (MPW) can help reduce holes and sparse regions, improve the visibility of distant splats, and produce smoother surface reconstructions. Lower values preserve finer detail but may introduce gaps or aliasing in thin regions.

There is a global switch for Min Pixel Width available in the Render Setup window.

The Min Pixel Width parameter can also be overridden on a per-object basis using the Arnold Properties modifier.

Input Color Space

Specifies the color space used to interpret splat color data. Choose the color space that matches the source dataset to ensure accurate shading and lighting.

Shading

Controls how each splat's stored color and radiance data is interpreted, shaded, and combined into the final image.

Emission Tint

Applies a color multiplier to the emission component of each splat. White preserves the original captured color; other values shift the emitted appearance for look development, grading, or matching scene lighting.

Emission Weight

Scales the contribution of each splat's stored radiance, treating splat color as emitted light. A value of 1.0 renders splats at their captured brightness; 0.0 disables the emission contribution.

Diffuse Tint

Applies a color multiplier to the diffuse component of each splat.

Diffuse Weight

Scales the diffuse shading contribution from scene lights. Use a non-zero value to have splats respond to Arnold lights; set to 0.0 for an unshaded, radiance-only look.

Diffuse Roughness

Controls the roughness of the diffuse response. Higher values produce a flatter, more uniform diffuse falloff across each splat.