Marek Posts Mesa Tessellation Support For RadeonSI Gallium3D

[phoronix]

Phoronix: Marek Posts Mesa Tessellation Support For RadeonSI Gallium3D

It looks like OpenGL tessellation shader support within Mesa/Gallium3D is finally about to become a reality! Prolific Mesa contributor Marek Olš?k has finished up the enablement work started by others and now has OpenGL tessellation working with the AMD RadeonSI Gallium3D open-source graphics driver...

http://www.phoronix.com/scan.php?page=news_item&px=Mesa-RadeonSI-Tessellation

[przemoli]

According to gl3.txt radeonsi needs:

one more from 4.0
two more from 4.1
there more from 4.2

[ernstp]

Cool!

[kaprikawn]

What do the Metro games require? I'd consider that to be a fairly good yardstick to measure by given that it's probably the most advanced tech that a lot of people use on Linux with regards to graphics.

This is great news and a significant achievement to all involved.

[Krejzi]

http://lists.freedesktop.org/archives/mesa-dev/2015-May/085401.html

GL_ARB_shader_subroutine patches were posted back in May. Still under review it seems.

[imirkin]

According to gl3.txt radeonsi needs:

one more from 4.0
two more from 4.1
there more from 4.2

Actually radeonsi is also missing ARB_gpu_shader5 and ARB_gpu_shader_fp64 from 4.0 (in addition to subroutines, which all drivers are missing but there are patches out for which will enable it for all drivers). However only 1 "real" one left in radeonsi from 4.1 (ARB_viewport_array) which should be fairly simple. The other two are roughly free once some of the 4.0 stuff is in.

You can see the state of extensions provided on various hw in released mesa versions at http://people.freedesktop.org/~imirk...o/glxinfo.html.

[kmare]

also ARB_framebuffer_no_attachments just got implemented for i965:

http://cgit.freedesktop.org/mesa/mes...f372f0c809f4bf

[godlike_panos]

Great news. I do believe that shader_storage_buffer and compute_shader are more important features. People should focus on these.

[r1348]

Awesome! Tesselation is a known performace killer, so I really wonder what the radeonsi performance impact will be... maybe another idea for a round of benchmarks? Radeonsi vs. Catalyst with tesselation on/off... Michael?

[haagch]

What do the Metro games require? I'd consider that to be a fairly good yardstick to measure by given that it's probably the most advanced tech that a lot of people use on Linux with regards to graphics.

Only shader subroutine. Dave's implementation works with it.

And mod(int,int), so a few shaders fail to compile. But it looks mostly okay: https://www.youtube.com/watch?v=e97hP1ys-7s

https://www.reddit.com/r/linux_gaming/comments/3a5t5f/metro_2033_redux_on_mesa_radeonsi_hd_7970m_very/

As for tesselation: https://imgur.com/a/pZSuq Works nicely. No crashes, no graphical glitches I can see.