Probe material nodes

Use Spectral Sampler when a material needs to read probe lighting explicitly. Supported ordinary lit materials should first be checked with the normal lighting path; adding another sampled contribution can otherwise change the intended lighting balance.

For the dedicated graph references, including connections, examples, and troubleshooting, see Spectral Sampler and Spectral Subsurface Boost in Spectral Material Nodes.

Spectral Sampler

Samples probe lighting at the current pixel. The current node has no position or normal input to wire. Its two outputs choose how the pixel's normal is used.

Normal output

Returns probe lighting evaluated using the pixel normal. The output is an RGB lighting value, not a normal vector, despite the short pin label.

Multiply an Unlit material's intended color by this value and connect that result to Emissive Color when you want the sampled field to provide its lighting.

Double Sided output

Returns probe lighting using the authored front-face normal on both sides. It is useful for thin, two-sided surfaces whose underside should retain the front-side lighting response.

This output does not turn a one-sided material into a two-sided material. Configure the material's own two-sided behavior separately.

Outside probe coverage

Both outputs return white outside coverage. Multiplying a surface color by the sample therefore leaves that color unchanged outside the field rather than forcing it black.

If an Unlit test material looks fully colored outside the field, that is the neutral fallback, not proof of valid baked probe coverage.

Sampling Quality

Default: Optimized. Choices: Optimized, Full L2.

Optimized retains ambient and first-order RGB directionality with a cheaper sampling path. Full L2 retains second-order directional information as well, with more atlas reads.

Full L2 preserves more directional detail. It does not add probe positions or improve a sparse grid. Compare its material cost against the visible difference.

This choice changes material compilation, not the bake settings. It can use the existing baked data.

Spectral Subsurface Boost

A bake-only adjustment placed between the material's subsurface color source and its Subsurface Color input. The runtime path keeps the original color.

Subsurface Color input

Required RGB input. Supplies the original subsurface color to preserve at runtime and modify for the bake.

Bake Boost

Default: 2. Minimum: 0; slider up to 4, without a declared hard maximum.

Multiplier used when the Boost pin is not connected. 1 preserves the bake color, 0 removes this bake-side subsurface contribution, and values above 1 increase it.

The resulting bake color is clamped to the supported 0-to-1 color range. Raising the multiplier after a channel has reached that limit cannot keep increasing that channel indefinitely.

Boost input

Optional scalar input that overrides Bake Boost. Connect a scalar parameter when material instances need different bake boosts. Negative values are prevented from creating a negative boost.

Rebake after changing the effective boost. This node does not replace the material's shading model or its normal runtime subsurface setup.