Light
Create a directional, point, spot, or area light for the 3D scene.
What it does
Light creates a light source that illuminates PBR-rendered geometry in a 3D scene. Type selects Directional (parallel rays, like the sun), Point (an omnidirectional bulb), Spot (a cone, like a flashlight), or Area (a rectangular emitter with soft, physically based falloff). Only the parameters that apply to the chosen type are shown: position and range are hidden for Directional, for instance.
The node has two outputs. light is the data form the scene's PBR lighting consumes directly. field is the same light expressed as a Colour Field, so it feeds anywhere a Colour Field is accepted: a Points or Sphere fill, a compositing graph, a volumetric preview. Wiring a Distance Field into Scene SDF gives the field output soft, distance-traced self-shadowing.
When to use it
Lighting a 3D scene. This is the light source node for PBR rendering.
The sun, or a broad flat wash of directional light: Directional type.
A bulb-like light that falls off with distance in every direction: Point type.
A focused, cone-shaped beam with soft edges: Spot type, with Inner and Outer Angle setting the penumbra.
A soft rectangular source such as a window or a softbox: Area type.
A light's glow as a Colour Field for shading, scattering or volumetric work: the
fieldoutput.
| Parameter | Type | Default | What it does |
|---|---|---|---|
light_type | String | "Point" | Type of light source. One of: Directional, Point, Spot, Area. |
position | Vec3 | (0, 100, 0) | Light position (ignored for Directional) |
direction | Vec3 | (0, -1, 0) | Light direction (normalized automatically) |
color | Vec3 | (1, 1, 1) | Light color (RGB, linear space) |
intensity | Number | 10 | Light brightness (can be > 1 for HDR) |
range | Number | 200 | Distance at which light reaches zero |
inner_angle | Number | 25 | Full intensity within this angle |
outer_angle | Number | 35 | Light fades to zero at this angle |
size_x | Number | 100 | Area light width (world units) |
size_y | Number | 100 | Area light height (world units) |
roll | Number | 0 | Rect roll around the light direction |
two_sided | Boolean | false | Two-sided emission (one-sided lights emit along the direction only) |
cast_shadows | Boolean | false | Cast shadows from this light (ray-traced; works for every light type) |
scene_sdf | SDF or Field | — | Optional scene SDF — wire to enable sphere-traced shadows on the field output |
shadow_softness | Number | 32 | Shadow penumbra hardness (k in `min(k·d/t, vis)`); higher = sharper |
Gotchas
Position is ignored for Directional lights, which have a direction and no origin, and Direction is ignored for Point lights, which radiate equally in every direction. The parameter panel hides whichever does not apply to the current Type.
Wiring a Distance Field into Scene SDF affects the field output only. It adds no shadows to the light output, which relies on the scene renderer's own shadow handling. Use Cast Shadows for that.
Outer Angle is always held at least slightly larger than Inner Angle internally, even when the two are set equal or crossed. A spot edge that reads unexpectedly soft or hard is usually the two angles fighting.
Cast Shadows applies to every light type. A Point or Spot light casts shadows just as a Directional or Area one does.
Worked example
Add a Light and leave Type as Point for an all-round bulb, or switch to Directional for a sun-like key light.
Set Position (for Point/Spot/Area) or Direction (for Directional/Spot/Area) to aim the light at your scene.
Raise Intensity until the geometry reads well. Values above 1 are fine for a bright HDR look.
For a Spot, narrow Inner Angle for a tighter hotspot and widen Outer Angle for a softer falloff at the cone's edge.
Enable Cast Shadows to have the light cast shadows in the scene. It works for every light type.
Optionally wire a Distance Field into Scene SDF to add soft self-shadowing to the
fieldoutput when the light is used as a Colour Field elsewhere.