[Mesa-dev] ANDROID: eglCreateImageKHR missing modifiers

[Emil Velikov]

Hi all,

Pardon for dropping in so late. I've seems to have missed this.

On 24 July 2018 at 14:24, Martin Fuzzey <martin.fuzzey at flowbird.group> wrote:
> Hi Thomasz,
>
> thanks for your reply
>
> On 21/07/18 04:27, Tomasz Figa wrote:
>>
>>
>> As you noticed, this adds back the dependency on gralloc handle
>> structure. Moreover, it actually adds a dependency on the handle
>> having a binary format compatible with gralloc_gbm_handle_t. This is
>> not something that we can do in upstream Mesa, since there are more
>> platforms running gralloc implementations other than gbm_gralloc.
>
>
> Looking at it a bit more is it really that bad?
>
Note that there are at least three different implementations - the
"original" drm_gralloc, gbm_gralloc (props to RobH) and an another one
used in CrOS (or was it Android?)


> The compile time dependency is on gralloc_handle.h which is actually part of
> libdrm not a specific gralloc implementation.
> Does mesa need to compile with old versions of libdrm?
> 0r is the structure going to be removed from libdrm?
>
I think you missed gbm in gralloc_*gbm*_handle_t. The header
gralloc_handle.h was added to libdrm by Robert Foss, explicitly to aim
and standardise things.


>>
>> Unfortunately, I don't have a very good solution for this. In Chrome
>> OS we just don't support modifiers in EGL/GLES on Android. Obviously
>> it would be a good idea to have some way to query gralloc for the
>> modifier, but I don't see Android providing any generic way to do it.
>>
>> The least evil I can think of as a makeshift for now could be an
>> optional gralloc0 perform call that returns the modifier for given
>> buffer.
>
>
> An advantage of a new perform call would be that other gralloc
> implementations could be extended to support it without changing their
> handle structure but is that really likely?
>
I did not keep track of the gralloc_handle_t discussion, but Rob
(cc'd) should have some info.
>From vague memory the standardized handle had means to track modifiers
amongst others.

That is obviously somewhat orthogonal to Android making it use of it ;-)

HTH
Emil