[Mesa-dev] Newbie task to get started

[Jakob Sinclair]

On 2016-04-12 11:00, Timothy Arceri wrote:
> On Sun, 2016-04-10 at 21:45 +0200, Jakob Sinclair wrote:
>> Hi! My name is Jakob Sinclair and I would like to start contributing
>> to 
>> mesa development. I was wondering if anyone has any easy tasks that I
>> as 
>> a newbie could start working on. I tried looking at 
>> https://wiki.freedesktop.org/dri/NewbieProjects/ but it seems that
>> page 
>> is outdated and most of the tasks over there have already been done. 
>> Thanks in advance for your help!
>> 
> 
> Hi Jakob,
> 
> Not sure if you have found something to work on yet. Also I'm not sure
> it fits the easy category but I did notice something recently that is a
> some what self contained piece of work. Currently there are two
> different ways for drivers to store and access uniforms.
> 
> In the struct gl_uniform_storage we have:
> 
>    gl_constant_value *storage
> 
> Which is used by glGetUniform and also directly in the Intel i965
> driver to access uniforms.
> 
> And we have:
> 
>    unsigned num_driver_storage;
>    struct gl_uniform_driver_storage *driver_storage;
> 
> Which is used by all other drivers e.g Gallium drivers, Intel i915
> driver.
> 
> Ideally we would could just make use of gl_constant_value *storage and
> we could get rid of all the helper functions etc used for the
> driver_storage such as _mesa_propagate_uniforms_to_driver_storage()
> currently gallium drivers are storing the data twice and even the intel
> driver will end up calling the progate function even though it just
> falls back to doing nothing.
> 
> It seems the reason driver for gl_uniform_driver_storage is historical
> (please someone correct me if I'm wrong) it makes use of the
> gl_program_parameter list to store uniforms in a way that predates the
> glsl compilers introduction to Mesa. This list is not ideal in itself
> since its just an array that needs to be regenerated as it grows
> meaning we need to hold only other information such as UniformHash in
> order to keep track of things that we could otherwise free also.
> 
> Anway I can see many things that could be cleaned up by reworking how
> this is handled. However it also looks like a big task and there are
> likely to be a number of issues that need to be solve in order to pull
> it off, but it will introduce you to a number of components that make
> up Mesa.
> 
> If you want to look into it further I sugest taking a look at
> how get_mesa_program() in st_glsl_to_tgsi.cpp works and also the
> various piece in ir_to_mesa.cpp that handle uniforms such as the
> add_uniform_to_shader class.
> 
> You also might want to check with some of the developers who work on
> gallium based drivers to see if this sounds like a reasonable idea
> before starting as I haven't had a huge amount to do with it in that
> past so I may be underestimating the work/problems involved.
> 
> Tim

Hi Tim! Thanks for the suggestion! It sound's very interesting and it 
could definitely be something I could work on, assuming that the other 
gallium developers agree to this.

On a side note: I actually remember way back when you did your 
kickstarter for mesa development and it's very awesome to see that you 
still work with mesa. Your old blog posts have helped me a ton in the 
last few days and you have done a lot of awesome work. Just wanted to 
say thank you and keep it up!

-- 
Mvh Jakob Sinclair