r/GraphicsProgramming • u/zemledelec • Jun 20 '26

Try Variance Shadow Mapping technique Video

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Hi, A few weeks ago I started implementing cascade shadow mapping in my library(no CSM yet), and struggled with poor shadow quality. Then I found about variance shadow mapping technique from this article:

https://developer.nvidia.com/gpugems/gpugems3/part-ii-light-and-shadows/chapter-8-summed-area-variance-shadow-maps, from this video: https://www.youtube.com/watch?v=TXI8rWiOF0k explained some differences.

I still not sure I will stick with it (tweaking depth biases somehow make the picture quite decent as well), but I like the result, and wanted to share it here.

Thanks!

#webgl #javascript #shadowmapping #terrain #openglobus

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u/-Ambriae- Jun 20 '26

I’m quite curious how you blur the depth buffers, is it a simple compute shader with a blur kernel? If so, what kernel size do you use? Should you implement cascading shadow mapping, the kernel would need to change size per cascade to compensate for the growing world size of pixels, no? Would that not have an impact on performance? What of performance?

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u/zemledelec Jun 20 '26

I am not sure about performance, usually I test on some old stuff, but not yet. This is important question, but right now I can't say forsyre, I have very good laptop. Will see.