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Separate Translucency Utility

Hi everyone,

I have a simple question : what is the use of separate tranlucency ?

I know it is used so that translucent objects are not affected by DoF but I can’t see any situations where I would want some objects that would pop from the DoF.

I know it also affect refraction but I’m just wondering if the cost is worth it if I don’t have any specific use of it.

Thanks :slight_smile:

To understand how it can be used, it helps to understand how it works. Objects rendered using separate translucency are drawn into a separate, off-screen render target that is later composited back into the screen (after DOF and motion blur). The biggest advantage is that the separate translucency buffer can have a different resolution than the screen buffer, so you can reduce its resolution for better performance when drawing fill-rate intensive effects like smoke and other translucent particles. You can reduce it manually using the r.SeparateTranslucencyScreenPercentage variable or configure it so UE4 dynamically reduces the resolution based on performance.