In the real world, light fades over distance, and dim lights have a lower range than bright lights. The term “fall-off” refers to the rate at which light fades. Alongside Unity’s default fall-off lighting behaviour, you can also use custom fall-off settings.
Progressive Lightmapper provides custom fall-off presets, which you can implement via script. See the image below the table for a visual representation of how these work, and the code sample below the image for an example of how to use this functionality.
Propiedad: | Función: |
---|---|
InverseSquared |
Apply an inverse-squared distance fall-off model. This means the light intensity decreases inversely proportional to the square of location’s distance to the light source. For more information , see Wikipedia: Inverse-square law. This option is the most physically accurate. |
InverseSquaredNoRangeAttenuation |
Apply an inverse-squared distance fall-off model with no smooth range attenuation. This works in the same way as InverseSquared , but the lighting system does not take into account the attenuation for the range parameter of punctual lights (that is, point lights and spotlights). |
Legacy |
Apply a quadratic fall-off model. This model bases the light attenuation on the range of the light source. The intensity diminishes as the light gets further away from the source, but there is a very sharp and unnatural drop in the attenuation, and the visual effect is not realistic. |
Linear |
Apply a linear fall-off model. In this model, attenuation is inversely proportional to the distance from the light, and the fall-off diminishes at a fixed rate from its source. |
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.Experimental.GlobalIllumination;
using UnityEngine.SceneManagement;
[ExecuteInEditMode]
public class ExtractFalloff : MonoBehaviour
{
public void OnEnable()
{
Lightmapping.RequestLightsDelegate testDel = (Light[] requests, Unity.Collections.NativeArray<LightDataGI> lightsOutput) =>
{
DirectionalLight dLight = new DirectionalLight();
PointLight point = new PointLight();
SpotLight spot = new SpotLight();
RectangleLight rect = new RectangleLight();
LightDataGI ld = new LightDataGI();
for (int i = 0; i < requests.Length; i++)
{
Light l = requests[i];
switch (l.type)
{
case UnityEngine.LightType.Directional: LightmapperUtils.Extract(l, ref dLight); ld.Init(ref dLight); break;
case UnityEngine.LightType.Point: LightmapperUtils.Extract(l, ref point); ld.Init(ref point); break;
case UnityEngine.LightType.Spot: LightmapperUtils.Extract(l, ref spot); ld.Init(ref spot); break;
case UnityEngine.LightType.Area: LightmapperUtils.Extract(l, ref rect); ld.Init(ref rect); break;
default: ld.InitNoBake(l.GetInstanceID()); break;
}
ld.falloff = FalloffType.InverseSquared;
lightsOutput[i] = ld;
}
};
Lightmapping.SetDelegate(testDel);
}
void OnDisable()
{
Lightmapping.ResetDelegate();
}
}
Progressive Lightmapper added in 2018.1 NewIn20181
2018–03–28 Page published with limited editorial review