The length of the barn door attached to the Rect Light. The angle of the barn door attached to the Rect Light. The extent of the Rect Light along its local Z axis. The extent of the Rect Light along its local Y axis. Like a Point Light or a Spot Light, a Rect Light has a spherical attenuation radius. As you increase the Source Width and Source Height of the light, you will need to increase the Intensity in order to maintain the same apparent brightness.īounds the light's visible influence.

Note that for Rect Lights, this value is averaged over the surface area of the light. The properties of a Rect Light are broken up into 4 categories: Light, Lightmass, Light Function and Light Profiles. If you need to use forward rendering in your Project, use a Spot Light or Point Light instead. The forward renderer does not currently support Rect Lights. Alternatively, you could opt to set the mobility of the light to Static, which has no effect on runtime rendering performance at all. The cost is also due in part to shadow casting, so you may be able to minimize the extra cost by turning off the Casts Shadows option. The exact cost scaling depends on the platform, but in general, Movable lights cost more than Stationary lights. Rect Lights that are set to Stationary or Movable are typically much more expensive to render than a Point Light or Spot Light with the same mobility. For example, in the image on the right above, the sharp shadow cast on the floor indicates that the light is emitted from the center of the rectangle. The actual light is emitted outward from the center of the Rect Light, similar to a Point Light. If your Rect Light is set to Movable, the width and height of the rectangle are only used for specular reflections. If you set your Rect Light to Stationary Mobility, you may be able to achieve better quality shadows by also enabling the Use Area Shadows for Stationary Light setting. However, this setting is typically the slowest to render. This allows your light to cast correct shadows from moving objects in the game at runtime every frame. None of its direct or indirect illumination is baked by Lightmass at all. Movable: With this setting, the light is totally dynamic.

This setting preserves the high-quality soft shadowing and global illumination pre-computed by Lightmass, but it also permits you to change the color and intensity of the light in the game at runtime.

The direct lighting cast by the light is calculated dynamically every frame in the game. Stationary: With this setting, only the indirect illumination from the light is baked into lightmaps when you build lighting for your level.

This is the fastest method for rendering, but it means that the light cannot be changed in the game at runtime. Static: With this setting, the light's direct and indirect illumination are both baked to lightmaps when you build lighting for your level. Like other types of light sources, Rect Lights have three Mobility settings: The Rect Light has a spherical attenuation radius, like a Point Light or a Spot Light. As shown in the image above, the Rect Light emits light within its sphere of attenuation only in the positive direction of its local X axis, similar to a Spot Light with its cone set to 180 degrees. However, specular highlights for Rect Lights show the width and height of the light's rectangular area. See the discussion on mobility settings below.Įach Rect Light has two key settings, Source Width and Source Height, which determine the size of its rectangle along its local Y and Z axes: RectLights do not behave like true area lights in all situations.

China dynamic light box