[Mesa-dev] Mesa build fails with xlib/egl

[Lionel Landwerlin]

On Tue, Jul 13, 2010 at 9:40 AM, Chia-I Wu <olvaffe at gmail.com> wrote:
> On Sun, Jul 11, 2010 at 1:18 AM, Lionel Landwerlin
> <llandwerlin at gmail.com> wrote:
>> Thanks for your response, it worked well.
>>
>> I have another question but first I think I need to give some context.
>>
>> I'm trying to build an environment on my laptop which mimics what I'm
>> going to use on an embedded target. What I expect to find on my embedded
>> target is a closed source libGL (EGL + GLES2.0) which is bound to the
>> linux frame buffer interface as native system. Hopefully I will have
>> access to an SDK which permits to "repackage" the GL library so it will
>> use x11 as native system.
>> Also I'm planning to use an X11 compositor to render the different
>> applications which run on the system, and also I expect applications to
>> use OpenGL for whatever stuff they need.
>>
>> In this scenario, I understand that everyone (including the xserver)
>> will use direct rendering (which means to me that no one is going to
>> forward its GL commands to the xserver, but maybe did I misunderstood
>> something).
>>
>> So my question is, how do I build such a system ? To be precise, what
>> options should I give to the configure script of Mesa ?
> If you are simulating the environment on your desktop, either egl_dri2 or
> egl_gallium should satisfy your need.  But you need to use a hardware driver.
> Neither of the EGL drivers supports texture-from-pixmap with a software
> rasterizer.

Ok.
But since I want to use a compositor, I need texture-from-pixmap...
So this might require some modifications in mesa drivers and other
libraries around.
*What follows is crappy*
My plan was to modify libdrm, so libdrm does not access the drivers
anymore. Instead
it will allocate buffers from some kind of server (hey looks like
wayland?) which just mmaps
buffers from files. So all clients/GL applications will be able to
access buffers allocated by
the X server.
At the moment I don't understand the interactions between DRI2 and
libdrm, so I don't yet
understand how buffers can be accessed from clients. Although I
understand how it works
with DRI driver in Mesa.

Does it make sense ?

>
> Both drivers support EGL_KHR_image_pixmap for t-f-p.  Only egl_dri2 supports
> EGL_NOK_texture_from_pixmap.  But it is trivial to add
> EGL_NOK_texture_from_pixmap support to egl_gallium.
>> Maybe am I wrong about this. Maybe indirect rendering will out perform
>> direct rendering in such configuration, so anyone comments/advices on
>> the subject are more than welcome.
> EGL does not define a protocol for indirect rendering.

Yes.

>> Thanks again,
>>
>> --
>> Lionel Landwerlin
>>
>>