radiance

Definition

A radiometric quantity: the light leaving a point in a particular direction. A radiance field assigns that value to every point and direction in space, and integrating it along a camera ray gives a pixel's color. The direction-dependence is the part that matters — it is why these representations reproduce specular highlights and reflections, which a plain per-point color cannot.

Explainers using this term

• The State of 3D Generation — From NeRF to Gaussian SplattingNeRF: Representing Scenes as Neural Radiance Fields for View Synthesis