[libre-riscv-dev] Vulkanizing

[Jacob Lifshay]

On Tue, Feb 18, 2020, 10:38 Scheming Pony <scheming-pony at protonmail.com>
wrote:

>
> Luke mentioned that you were going with Vulkan for the graphics API, no
> dissent was allowed.

Dissent is certainly allowed, but it's not really practical to switch at
this point, since I've already written a large portion of one of the
drivers. Also, Vulkan is low-level enough that it can relatively
efficiently be used as the target for translating other graphics APIs to,
and, since it isn't 30 years old, it doesn't have a giant mountain of
legacy stuff that needs to be implemented.

see page 9 of
https://www.khronos.org/assets/uploads/developers/library/2019-xdc-montreal/Khronos-XDC-Montreal_Oct19.pdf

  My idea would be to go straight to ray tracing, but the available
> horsepower probably wouldn't be enough.  nVidia did have a ray tracing
> extension for Vulkan--is that standard now?


Not standard just yet, they're going to have the latest progress report at
GDC 2020:
https://www.khronos.org/events/2020-gdc
search for ray tracing

I told Luke that I'm at OpenGL 2.0 with GLSL and it's hard for me to move
> on.  RenderMan would be another alternative for a shader language.
>

The shader language Kazan is designed to use is the shader variant of
SPIR-V, which is a compiler intermediate language. There are several
front-ends which target it, some of which compile GLSL (including OpenGL
2.x) to SPIR-V. There might be a front-end for RenderMan, I'm not sure --
someone will probably write one at some point. If you're looking, just make
sure that whatever front-end you use supports producing the shader variant
since there is also a quite different (OpenCL) kernel variant of SPIR-V
which Kazan won't support (at least without lots of work).

>
> Whatever happened to the ownership of the SGI graphics hardware designs?
> What ever happened to Digital Alpha?  What ever happened to Thinking
> Machines?
>

I'm not sure, I would guess that HPE currently owns Alpha, since DEC was
acquired by Compaq which was acquired by HP.

I know there is an open-source OpenGL 1.x GPU on GitHub, I don't recall if
it came from SGI.

Jacob