Find if pixel is in shadow

Development Rendering
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1

Hi there,

I’m trying to control the look of my shadows (different shadow colors for different materials for example) and I’m struggling to access the shadow map.

I was using the following process (forward shading + LightAttenuationTexture) in 4.18 :

But since 4.19 the LightAttenuationTexture appears to be black and no longer contains shadows from the engine. Is there a way to achieve the same effect with recent version of the engine ? Looking through the .ush files I’ve found the following function :

float ShadowDepth = Texture2DSampleLevel(ForwardLightData.DirectionalLightShadowmapAtlas, ForwardLightData.ShadowmapSampler, ShadowUVs, 0).x;

But trying to access it from a custom node in the material editor crash the engine.
Maybe there is a way with SceneCapture to generate my own shadow map but I don’t know if that’s possible to compute it for a point light ?

Any help appreciated !

edit : found this related issue : Unreal Engine Issues and Bug Tracker (UE-61513)

2

Three year is a long period and I also wonder if there is a solution in the recent version engine.

3

Just a note from 2024: UE5.3 is still crashing if trying access ForwardLightData from a Custom material node.