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DX11 MSAA Deferred Renderer

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I know with DX11, it is possible to have proper MSAA with a deferred renderer, but I am wondering how realistic this is in practice with current tech. My main concern is GPU memory for 4X MSAA, if all my render targets are 4X bigger.

I have a big dev monitor (2560x1600), so one fullscreen 32-bit render target weighs in at 16MB. So 4X ups it to 64MB.

I have 32-bit normal buffer, 32 bit diffuse albedo buffer, 32-bit spec albedo buffer, 32-bit depth/stencil buffer, 32-bit copy of depth/stencil buffer (for reading from shader since I need to support DX10), 64-bit HDR light accumulation buffer, fullscreen refraction map. This does not count buffers for CSM, SSAO, ToneMapping, etc.

Geforce 680 only has 2048MB, so with MSAA I am eating a huge percentage of that memory for MSAA. My monitor is above average size, but still.

Obviously I could support it for high-end systems, but I am wondering if I should devote my time to the older DX9 deferred rendering AA styles that used edge detection.

Do a lot of current AAA games not use MSAA for deferred rendering?

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Dropping in something like FXAA will take you an hour or two. Seriously, it's that easy. So I don't think between MSAA and FXAA, instead your decision should be whether it's worth your time to implement MSAA [i]in addition[/i] to FXAA. AAA games have shipped with deferred rendering + MSAA...Battlefield 3 is is the first one that comes to mind. A lot of AAA games have shipped on PC without MSAA support, particularly those that use DX9.

Looking at the [url="http://store.steampowered.com/hwsurvey/"]Steam HW survey[/url], most people don't go over 1920x1080 resolution. Which means your 2560x1600 is an abnormally high-end case to consider. MSAA at 1920x1080 should definitely be doable on a high-end GPU, even with a deferred renderer.

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Personally I preffer the results of SMAA: http://www.iryoku.com/smaa/

But, really MJP is correct, there's no particular need for getting together MSAA in deffered renderer unless you really don't like aliasing. There was a paper, a recent paper, describing how to get the memory cost of MSAA in deffered down to something similar to a forward renderer, but unfortunately I can't seem to remember what it was called.

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