Challenges and solutions

Recreating a Half-Life: Alyx Inspired Liquid Shader

The liquid shader in Half-Life: Alyx is an impressive effect in the Source 2 engine. I needed to create a similar effect in Unreal Engine for its specific use case.

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Solution:

• Instead of directly replicating the effect, I applied a ‘smoke and mirrors’ technique.

• A low-poly egg shape inside the pod acts as the liquid volume.

• The shader applies to this shape, giving the illusion of a draining effect, adapting to the pod orientation.

• A glass surface material with refraction and a tiled normal map helps conceal the fact that the liquid lacks a cap.

• Future Improvement: I’d like to revisit this and explore adding a dynamic cap. 

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Developing an Efficient Subsurface Material

I created a custom material function with a subsurface scattering input that works in conjunction with a custom output from Substance Painter. This looks great for materials like curtains and plastic containers. But it doesn't work well for realistic skin.

Solution:​

• Instead of using my shader, I opted for built-in skin shader in Unreal. Although its more expensive, it delivered exceptional results.

• My shader is still used and works perfectly for skin when used in a VR game, or for non-skin assets