MSAA on shadow pass

Currently I am able to set MSAA 4x on G-Buffer pass, but the shadow line is still jagged. I tried to set the sampleCount on my shadow pass but it didn’t work. So I’m wondering if it is possible to perform MSAA on shadow.

Screen Shot 2021-02-17 at 16.55.16

Thanks

The shadows in the book are low quality shadows. This link might help you towards resolving your issue: Common Techniques to Improve Shadow Depth Maps - Win32 apps | Microsoft Learn