[Mesa-dev] [RFC PATCH] mesa: Add MESA_SHADER_CAPTURE_PATH for writing .shader_test files.

[Marek Olšák]

On Mon, Jan 18, 2016 at 6:12 PM, Eero Tamminen
<eero.t.tamminen at intel.com> wrote:
> Hi,
>
> On 18.01.2016 17:05, Kenneth Graunke wrote:
>>
>> This writes linked shader programs to .shader_test files to
>> $MESA_SHADER_CAPTURE_PATH in the format used by shader-db
>> (http://cgit.freedesktop.org/mesa/shader-db).
>>
>> It supports both GLSL shaders and ARB programs.  All stages that
>> are linked together are written in a single .shader_test file.
>>
>> This eliminates the need for shader-db's split-to-files.py, as Mesa
>> produces the desired format directly.  It's much more reliable than
>> parsing stdout/stderr, as those may contain extraneous messages, or
>> simply be closed by the application and unavailable.
>
>
> It also has the advantage that if IDs get recycled, it will just overwrite
> earlier file with the newer one, whereas split-to-files.py ignored later
> shader using same ID. Shaders used e.g. for game menus and startup are less
> interesting than ones used during gameplay.
>
> If one wants startup shaders not to be overwritten, one can just kill the
> program at that point.  One could also somewhat differentiate shaders to
> different game stages (startup, menus, level 1, level 2....) by their file
> time stamps.

Wait, are you saying that this capturing method will overwrite shaders
sharing the same ID, leading to incomplete shader dumps? That's quite
a showstopper in my opinion.

The method we use is:
ST_DUMP_SHADERS=file
split-to-files.py file ..

There is no editing required.

Marek