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d3d11 Hardware Geometry Shader

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In the NVIDIA "GPU Programming Guide Geforce 8 and 9 Series" they basically say that the GS is not very good, and really only recommend it for point sprites. This document is about 3 years old now, and I am just wondering if anyone has read in a newer document that they have improved things with Fermi architecture.

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With SM5 you have more powerful tool to generate new vertices/triangles - tessleation (hull & domain shaders).
For example read this: [url=http://developer.download.nvidia.com/presentations/2008/Gamefest/Gamefest2008-DisplacedSubdivisionSurfaceTessellation-Slides.PDF]Tessellation of Displaced Subdivision Surfaces in DX11[/url].

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In my experience it's generally okay as long as you don't emit too many new primitives/verts, and your post-vertex-shader vertex structure isn't too big. Using it for tessellation or to send a single primitive to multiple render targets just isn't worth it.

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[quote name='MartinsM' timestamp='1305397991' post='4810796']
With SM5 you have more powerful tool to generate new vertices/triangles - tessleation (hull & domain shaders).
For example read this: [url="http://developer.download.nvidia.com/presentations/2008/Gamefest/Gamefest2008-DisplacedSubdivisionSurfaceTessellation-Slides.PDF"]Tessellation of Displaced Subdivision Surfaces in DX11[/url].
[/quote]
The problem with this is that you can only generate triangles. If you want more fine control over what you are making, the GS is a good choice. However, as MJP said, it has to be used for the right things. I have found that the sending of geometry to multiple render targets can be helpful in a number of cases, especially if there is some moderately expensive vertex level processing (i.e. skinning).

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