Nvidia's PCSS soft shadow algorithm implemented in Unity
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TheMasonX Yup, shader variants were the issue. I set it up to track the shader …
…variants used in the editor, and started removing some of the unnecessary variations
Latest commit 9a6762f Jan 24, 2018

README.md

UnityPCSS

Nvidia's PCSS soft shadow algorithm implemented in Unity3D.

Description

"PCSS" or "Percentage Closer Soft Shadows" is a shadow sampling algorithm invented by Nvidia in 2005 (Original Whitepaper). The intent is to simulate a more realistic falloff where the shadows get progressively softer the further the receiver is from the caster.

This effect is easy to spot in real life, such as when looking at tree shadows: alt text

I thought this photo was really cool, so I did a quick recreation as a test: alt text

Current Limitations

Currently only works with "Directional" light sources, as it's primarily an override of the "Screen Space Shadows" shader in the graphics settings, but I'm looking into the possibility of directly overriding the actual "UnityShadowLibrary.cginc" to affect "Spot" and "Point" lights if possible.

Version Compatibility

The shadows themselves do work with 5.5, 5.6, and 2017 (no modifications necessary, it automatically detects and adapts to either version), but as this is now a Unity 2017 project, the materials in the demo scene do not import correctly in 5.5 or 5.6. There are only 3 or so materials that need their albedo/metallic/specular textures assigned from the nearby "Textures" folder, so it's not that bad, but if anybody has any ideas to fix this, please let me know! :)

Future Development

This asset and any improvements will remain free (both as in beer and speech), but if you wish to support me spending extra time on this, you can donate to me through PayPal. NOTE: Please do not feel pressured to donate it's just an option if anyone wishes to support me spending more time on this, and less on my game, which I can't even use it for.

I obviously didn't do this to make money though; instead, I'd prefer support in the form of you guys contributing back any fixes/improvements, so that we can all benefit :) I made it Open Source rather than just a free asset because I believe that if we work together, we can create something truly amazing. Thanks for the interest, and I hope you guys get some good use out of it! Let me know if you have any issues or ideas, and I'll respond to pull requests ASAP.