Parametric Lights

Parametric Lights are available from ​Version 2023.2​​.

In addition to the default HDRI lights, version 2023.2 supports ​Parametric Lights​​. Parametric Lights provide the ability to create custom lights which improve the overall look of the render output. Using Parametric Lights reduces dependency on HDRI which requires more computing power for Unreal.
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When using Parametric Lights, bear in mind that the direction of the light source is determined by setting the angle of the lights source. The following custom lights are supported:

• ​​​Area light: ​​The light source is projected in a specific direction, in a rectangular shape. This light source can be compared to a window where through which light shines in.
• ​​​Spotlight: ​​A light source projected in a specific direction, in a circular shape. This light source mimics the light in a studio or on a stage. The light source fades away at the edges.
• ​​​Directional Light: ​​A strong light source, like the sun. The light source is from a specific direction and angle, without a specific shape and projects light endlessly in all directions.
• ​​​Point Light:​​ Similar to a regular light bulb, this light source has no specific direction, shape or angle and projects light in all directions.

To choose the lighting:

1. On the ​Main ​​menu, click ​3D Environment​ and then ​Add Lights​​. You can also view the lighting options under ​Lights ​​in the ​3D Resources​ tab. To do this, click the ​+ ​​icon next to the ​New Lights Preset​​ drop-down list. The following lighting options are available:
   
2. Select the lighting option you want to use. The parameters for the selected option appear in the ​Context view​​. Depending on the lighting option selected, a window similar to the following appears:
   
3. Adjust the parameters as necessary.

• A description of all possible parameters follows:

  • Type​​: Select the type of light source.

  • ​​Color: Select the color of the light source.

  • ​​​Intensity​​: Allows you to set the intensity of the light source.

  • ​​Distance: Available for Area Light.

  • ​​Angle: Available for Spotlight. Determines the angle of the light source.

  • ​​Falloff: Available for Spotlight and Directional Light. Determines how light is dimmed towards the edges of the light beam.

  • ​​Width: Available for Area Light only. Determines the size of the light source shape.

  • ​​Height: Available for Area Light only. Determines the size of the light source shape.

  • Cast Shadow​​: Allows hiding the default shadow that appears (based on HDRI parameters).

  • ​​3D Object: Allows hiding the 3D objects which project light. You can also toggle the ​​​eye.PNG​​ icon next to the light type in the ​3D Resources​​ tab.
  • ​​3D Transformation​​: Allows manually adjusting the ​3D Gizmo​​ parameters.
    
    • ​​Version 2023.3: ​​As of this version, the same transformation capabilities are available for the different types of Parametric Lights. This allows easily moving from using one type of parametric light to another. Spot, Directional and Area lights use local transformations. This means that the 3D gizmo will always be aligned with the object coordinates. Point lights use world transformation, which means that the 3D gizmo will always be aligned with the world coordinates. For point lights, it is only possible to move the 3D gizmo (no rotation).