Remove 16× MSAA support due to driver bugs and low performance #49063
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nathanfranke
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Jul 4, 2021
In the `master` branch, 16× MSAA caused the entire system to freeze on NVIDIA GPUs. This is likely caused by graphics drivers not actually implementing 16× MSAA, but combining 8× MSAA with 2× SSAA instead. On top of that, modern shader complexity makes 16× MSAA very difficult to use while keeping a good framerate. 8× MSAA is hard enough to use as it is.
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akien-mga
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In the
masterbranch, 16× MSAA caused the entire system to freeze on NVIDIA GPUs. This is likely caused by graphics drivers not actually implementing 16× MSAA, but combining 8× MSAA with 2× SSAA instead. If you need to implement a "photo mode" for high quality in-game screenshots, you can combine 2× SSAA with 8× MSAA manually.On top of that, modern shader complexity makes 16× MSAA very difficult to use while keeping a good framerate. This is especially true when you start using GIProbe or SDFGI. 8× MSAA is hard enough to use as it is, and it's not much of a loss visually compared to 16× MSAA.
In the
3.xbranch, there are only minor bugs with 16× MSAA such as #14727, so I think we can keep it there. Shaders are also not as complex in3.x, so higher MSAA values are more usable in practice.This closes #37917.