[Mesa-dev] [PATCH] [RFC] egl: propose simple EGL_MESA_image_dma_buf_export v2.2

[Dave Airlie]

On 4 March 2015 at 05:06, Chad Versace <chad.versace at intel.com> wrote:
> On 03/03/2015 11:01 AM, Daniel Stone wrote:
>> Hi,
>>
>> On 3 March 2015 at 18:40, Chad Versace <chad.versace at intel.com> wrote:
>>> On 03/03/2015 12:13 AM, Daniel Stone wrote:
>>>> On Tuesday, March 3, 2015, Dave Airlie <airlied at gmail.com <mailto:airlied at gmail.com>> wrote:
>>>>     +    EGLBoolean eglExportDMABUFImageQueryMESA(EGLDisplay dpy,
>>>>     +                                  EGLImageKHR image,
>>>>     +                                 int *fourcc,
>>>>     +                                 int *num_planes);
>>>>
>>>>
>>>> Shouldn't this contain the modifier(s) as well?
>>>
>>> What is the motivation for defining two export calls, and exporting
>>> a subset of information from each call? I don't understand why the
>>> fourcc values are exported by one call, but the strides exported a
>>> separate call.
>>
>> Querying the image gives you what you need in order to know if you can
>> actually deal with the image, before you go to all the effort of
>> exporting it.
>
> Thanks. That makes sense.

Also you need the number of planes to correctly size the arrays for
the second call to put the results into.

Dave.